Gearing Up Robotics

Page 1

STACK, LLC


STACK, LLC (STELLAR ALTERNATIVES FOR CLASSROOMS AND KIDS) is not associated with LEGO速, LEGO速 MINDSTORMS速, and ROBOLABTM software are trademarks of the LEGO速 Group.

This material was developed under the auspices of STACK, LLC by Jason Jirsa, Julie Blue and Dr. Brad Blue.


Getting Prepared

Programming & Engineering ™

Table of Contents Section 1: Getting Prepared

4

4

Curriculum Overview

Supplies and Practical Matters

5

Section 2: Gearing up for Engineering

Engineering 1: Bits and Pieces

9

Engineering 2: LEGO Landers

14

Engineering 3: LEGO Roving Vehicle

Engineering 4: Build the Basic Chassis

8

18 22

Section 3: Gearing up for Programming

23

Programming 1a: Decipher Program One

25

Programming 1b: Recreate Program One

30

Programming 2: Decipher Turns

Programming 3: Inputs and Outputs

Programming 4: Graphing and the Rotation Sensor

31

Section 4: The Next Challenge

Additional Information

32 38

44

45

The Student Logbook Constructopedia

46

59

Bits and Pieces B Building Instructions

60

LEGO Lander Building Instructions

LEGO Roving Vehicle Building Instructions

Basic Chassis Building Instructions

Basic Motor Mount Building Instructions

Recreate Program One Instructions

67 75

90 108

111


Programming & Engineering ™

Getting Prepared

Section One: Getting Prepared Curriculum Overview

Teaching a robotics unit with LEGO MINDSTORMS is exciting. Students are immediately engaged. They demand to know how to engineer more capable robots and how to program them to obey their commands. The key to turning students into young programmers and engineers is tools and curriculum that make these skills accessible but that also continue to challenge students long after their initial introduction. LEGO MINDSTORMS does this. From the first day any student can build with LEGO elements. They are immediately familiar. But anyone who has not shopped for LEGO kits recently will be surprised by the large array of elements available. The addition of a programmable LEGO brick, known as the NXT, motors and sensors turns a familiar box of plastic into a tool that entertains even the most sophisticated aspiring engineer (and many real engineers too). The LEGO MINDSTORMS Education software is also easily accessible. Instead of copying pages of syntax to create the simplest of programs, this programming language, known as NXT-G, uses icons to represent common behaviors. The process is simple enough that any student could program their robot to demonstrate a behavior with minimal instruction, but getting the robot to produce the right behavior is more challenging. As students learn NXT-G they learn to ask the same questions that professional computer programmers ask. Gearing Up for Programming and Engineering is an introduction to both tools. This 15-hour unit teaches students the technical language they’ll need to communicate with their teammates and the skills they’ll need to make their robots successful. This structured unit is meant to be a beginning. After Gearing Up for Programming and Engineering students will be eager to use their abilities to design, test, evaluate and improve impressive robots. Teachers should be prepared to follow up the unit with a competition or project that requires the students to use these skills in a meaningful way. Several suggestions are included at the end of this document. The primary value of robotics is that it is engaging and hands-on. Students learn through inquiry. As they ask questions about how to improve the robot the teacher is given an excellent opportunity to include relevant content. Students wanting to study how their robot moves will find that they need to understand how to collect data, measure and graph. Students completing a science-themed challenge will want to know what the parts of the challenge represent. And, robotics involves students in the same type of design experience recommended by the National Science Education Standards for Science and Technology. In fact, a robotics teacher reading about how students should learn to identify problems, plan solutions, create prototypes, test and evaluate the results


Getting Prepared

Programming & Engineering ™

would think that the “Abilities of Technology” section was written with robotics in mind. LEGO MINDSTORMS robotics is taught in many settings including classrooms, after school programs and special camps. Although the activities that follow have been presented with the middle school classroom in mind, they have been modified and tested in all of these settings with great success.

Supplies and Practical Matters A good robotics experience requires good planning. The following is a list of items to consider before beginning a robotics unit. •

Teams: This curriculum was written based on a class divided into teams of two students. Using other team sizes or using sharing supplies between multiple classes meeting at different times is possible, but it may require adjustments and additional supplies.

LEGO Hardware: All of the LEGO hardware and software for this curriculum can be purchased from PITSCO (www.legoeducation.com or 1-800-362-4308). Each team will require a LEGO Education Base Set (W979797) as well as a kit of additional LEGO elements prepared specifically for this curriculum. In addition to all of the motors, sensors and elements needed for the activities, these also include rechargeable batteries and chargers for the NXT brick.

Software: This curriculum is designed to utilize the LEGO MINDSTORMS Education Software. For most schools the smartest option is to purchase a site license that allows the user to legally install the software on multiple computers (W991280).

Computers: Each team will need access to a computer that is capable of running this software. The software requirements are listed below.

Windows XP or Windows Vista

Apple Mac OS X (v. 10.3.9 or 10.4)

Pentium processor, 1 GHz minimum (1.5 GHz or better recommended) 256 MB RAM minimum (512 MB recommended) Up to 300 MB of available hard-disk space XGA display (1024 x 768) One available USB port

PowerPC G3, G4, G5 processor, 600 MHz minimum (1.3 GHz or better recommended) Intel processor, Apple Mac OS X 10.4 256 MB RAM minimum (512 MB recommended) Up to 300 MB of available hard-disk space XGA display (1024 x 768) One available USB port

The Classroom: Throughout this unit students will need access to a work area, computers, team storage and additional LEGO elements in the same room. The team workspace should allow the students room to discuss their ideas and to create their robots. Pushing desks together, assigning the students to tables or even designating spots on the floor could accomplish these goals. One consideration when designating the workspace is the location of computers. Students will be


Programming & Engineering ™

Getting Prepared

moving between their workspace, computers and the additional LEGO elements often, so a sensible traffic plan is essential. Also, since several parts of the curriculum recommend the use of an LCD projector, this should be included in the computer plan. Each team will need a secure place to store their robot, related cords and paperwork. Some teachers use a shoebox-sized or larger tupperware for this. Others designate locations on shelves or in cabinets. The final problem is the location of unused LEGO elements. Some teachers have attempted to keep each LEGO MINDSTORMS kit complete and together, but most find that this is frustrating and counterproductive. The solution to this problem is to keep kits in one set location. Many teachers choose to keep part of their LEGO collections sorted using the sorting trays that are included in each kit. •

Individual Logbooks: Before starting the unit, the teacher can create logbooks for each student by copying the pages included at the end of this document. Answer keys for the pages in the logbook are included with each activity. These logbooks include warm-up activities that the teacher can use to engage students at the beginning of class and several items that can be used for assessment. The logbooks should also serve as a reference for students when they complete future robotics challenges.

Color Copies: The CD-ROM included with this curriculum includes building instructions for the several of the activities. Since these are easiest to understand in color, teachers may wish to arrange to print copies for each team. The CD-ROM also includes large posters with element nomenclature and the design cycle that can be printed for classroom walls.

Stamps: The curriculum includes the use of stamps for common programming icons. These allow students to think about programs without the distractions of the computer. Be sure to have one set and a stamp pad for every four students. If these are not available, use programming stickers instead. The CD-ROM includes a file that can be printed on address labels to create custom programming stickers.

Management and Procedures: Robotics requires more movement and materials than most classroom activities. That is part of its appeal, but it is also a challenge for teachers. Successful robotics teachers, like any other teacher, have clear expectations for student behavior in these situations. It’s also helpful to solicit the help of parents or student mentors. Teachers might also wish to create a job board listing clean-up jobs assigned by group. These might include cleaning LEGO elements from the floor, cleaning LEGO elements from tables, sorting LEGO elements, checking to see that previously sorted LEGO elements remain sorted and checking to see that computers are properly shutdown. Teachers might also want to assign groups to set up the room or to take photos of the class’s efforts.

Teamwork: The most challenging aspect of robotics for many students is not design or computer programming, but teamwork. Teachers may want to prepare students for these challenges with their own “Gearing Up for Teamwork” unit (Some ideas are provided on the CD-ROM).

Time: Teachers should plan to spend approximately 15 hours of instruction time completing the Gearing Up curriculum. Time is distributed as follows:


Getting Prepared

Programming & Engineering ™

Gearing Up for Engineering Engineering 1: Bits and Pieces Engineering 2: LEGO Landers Engineering 3: LEGO Roving Vehicle Engineering 4: Build the Basic Chassis

1 hour 2 hours 2 hours 2 hours

Gearing Up for Programming Programming 1a: Decipher Program One Programming 1b: Recreate Program One Programming 2: Decipher Turns Programming 3: Inputs and Outputs Programming 4: Graphing and the Rotation Sensor

1 hour 1 hour 2 hours 2 hours 2 hours

Sequencing: These activities could be done in the order above. The advantage of this is that the students build the robots that they will need to complete the programming activities. The obvious disadvantage is that they do not program a robot until they’ve completed at least 7 hours of curriculum. Some teachers solve this problem by constructing the basic chassis before the unit begins. This allows the teacher to alternate the engineering and programming activities. The following sequence is another option: - - - - - - - - - -

The teacher builds a basic chassis for each group. Engineering 1 Programming 1a and 1b Engineering 2 Programming 2 Engineering 3 Programming 3 Engineering 4 (The students take apart and rebuild the robots) Programming 4 Robotics Event


Engineering

Programming & Engineering ™

Section Two: Gearing Up for Engineering The benefit of using LEGO elements for design is that they are familiar to many students, but when children build at home it is usually a solitary experience. In the robotics lab students are encouraged to collaborate and to discuss their design. In the following activities students learn to communicate using a shared technical vocabulary. LEGO elements may be familiar to most students, but if given the task of designing a robot without preparation many will not know where to start. Three of the activities in Gearing Up for Engineering use increasingly sophisticated building instructions to gradually introduce students to building strategies. After building, the students explore and test the strategies needed to build stable robots that don’t fall apart and robots that use motors, gears and pulleys to create motion. In the final Gearing Up for Engineering activity, the students build the robot that they will use in the Gearing Up for Programming section. As robotics students build they very naturally follow the design cycle, a set of steps that engineers use to design a product. Students identify engineering problems, brainstorm possible solutions, plan, test and evaluate. The design cycle is a key component of national and state science and technology standards, so teaching it is often a key objective of robotics activities. The building activities that follow are designed to facilitate this process.

The Design Cycle Investigate

Find a problem worthy of your creative genius. Research to see how others have solved the problem.

Investigate

Identify the Problem Research

Plan Plan

Evaluate

Brainstorm Choose a Solution

Test Refine

Create

Build a Prototype

Brainstorm many possible solutions. Choose the best solution.

Create

Turn your ideas into a prototype.

Evaluate

Test your design. Decide how to refine the design. Are there more problems to solve?

gems ™

The file needed to create this poster is included on the CD-ROM.


Engineering

Programming & Engineering ™

Engineering 1: Bits and Pieces Part A

Overview: All engineers share a technical language; in these activities the students learn the nomenclature they will need to communicate in the building activities that follow.

Objective: Upon completion of this activity students will be able to . . . 1. DISCUSS: why engineers need a shared vocabulary. 2. COMMUNICATE: using LEGO element names including brick, beam, gear, axle, plate, bushing, nail and liftarm.

Time: 1 hour Materials: • •

Ziploc bag with presorted LEGO elements (see below) Computer, Projector and Gearing Up CD-ROM

Teacher Preparation: • •

Open “Activity1.ppt” from the Gearing Up CD-ROM. Create a Ziploc Bag for each student that contains the following elements:

1

1x2 Brick

1

2x2 Brick

1

1x8 Beam

1

1x12 Beam

1

24 tooth Gear

1

8 tooth Gear

1

#10 Axle

1

#3 Axle

1

2x8 Plate with Holes

1

1x2 Plate

2

Full Bushings

1

Black Nail


Engineering

Programming & Engineering ™

1

Gray Nail

1

Motorcycle Wheel

1

#5 Liftarm

1

#9 Liftarm

Warm Up Ideas: The question for this warm-up on the Power

Point presentation is “How would you describe this LEGO element to a teammate?” The students should record the answer in their individual logbook. After the students are finished, the teacher should create a class list of possible answers. These might include color, size, shape or function.

Procedure: 1. Divide the students into pairs and give each student one of the prepared Ziploc bags. 2. The students should then take a moment to verify that each has the same elements as his/her partner. The teacher should then instruct them that after this point, they should not look at their partner’s elements. This is key. Students can sit back to back or use dividers to make sure that they cannot see what their partner is doing. 3. The teacher should instruct the students that one member of each pair will be the designer. The designer’s creation need not be functional or visually appealing, but it should use most of the pieces. The building process should only take a few minutes, so while the designers are building the other member of the pair can explore the bag of elements. 4. Once it appears that the designers have fairly substantial creations, the teacher should explain that the other member of each pair will be the listener. Each designer will describe to his/her listener how to build what he/she has just created. The students should not be looking at each other’s elements, but they should ask their partners questions. 5. As students finish, the teacher should ask them to compare their designs. How well were they able to reproduce the original design? Where did they experience problems? Did they feel like they were speaking different languages? 6. After most groups finish, the teacher can lead a class discussion. Most students will agree that one of the more challenging parts of this activity is describing individual LEGO elements. Even those that are successful find that it takes several sentences to describe each element. For this reason LEGO enthusiasts, and engineers for that matter, have accepted names for the tools that they use. 7. At this point the teacher should use the Power Point on the CD-ROM to teach the names of each element. The Power Point contains large images of the elements listed on the next page and a section for review.

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Engineering

Programming & Engineering ™

1

2

Bricks

Bricks are described by the number of bumps, or studs, on the top. This brick is one stud wide and two long, so it is called a “one by two brick”.

Beams

Beams look like bricks with holes, but they are also measured by the number of studs on the top. The smaller is a one by eight beam and the larger is a one by twelve beam. Be careful not to count the holes by mistake.

Plates

Plates are one third the height of bricks. They are also measured by the number of studs on top. These are a 2 x 8 plate and a 1 x 2 plate.

Liftarms

Liftarms come in many shapes and sizes, but they are usually named by the number of holes. These are a #5 and a #9 liftarm.

3

Axles

Measure an axle by holding it up to something with studs (like this beam). Notice that this is a three-stud (or #3) axle.

Gears

Most gears are measured by the number of teeth. The larger gear is a 24-tooth gear and the smaller is an eighttooth gear.

Nails

Nails are also often called pegs. Ask the students to put these two nails in a beam to discover how they are different. The answer is that the black nail is designed to stay in place within the beam while the gray nail is designed to turn.

Bushing

A bushing is used to hold items in place along an axle.

Wheel

This wheel is called a motorcycle wheel.

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Programming & Engineering ™

Engineering

8. The teacher should then instruct the students to try building again using the language. This time the designer should be the listener and the listener should be the designer. 9. As the students finish the teacher can lead another discussion. Were the names helpful? What parts of the activity were still difficult? What have they learned that will help them to design their robot?

Part B Materials: • • • •

Copy of the Element Inventory Sheet for each student (located in the Constructopedia) Copy of the Teacher Building Instructions (located in the Constructopedia) One sorting tray or small container for each pair Document camera and projector (optional)

Teacher Preparation: Each pair will need all of the elements listed on the student inventory sheet. The teacher should check to be sure that there are enough of each element. Adjust as necessary.

Procedure: 1. The teacher should divide the students into pairs (or each individual can build if there are enough LEGO elements). 2. In this version of the Bits and Pieces activity the students will gather their own elements from the sorted LEGO bins, but before starting the teacher should explain how the LEGO elements are organized and set rules for their use. Then the teacher should distribute sorting trays or another container and a copy of the student element inventory sheet. The students should then collect the elements. The teacher should encourage students to use the proper names of elements as they search. 3. During this building activity the teacher should use the instructions in the Constructopedia to instruct the students how to build this model step-by-step. The instructions include written directions, but the teacher should expand on these emphasizing language and technique. 4. The activity continues until the model is built. At the end of the activity teachers can use this model to discuss pulleys and gears.

Assessment: Teachers can use the Name that Element page in the Individual logbook with students or they might ask students to create written instructions for one of their creations.

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1

Answer Key ™

Name That Element

Write the name of each element in the space provided. Be sure to include the size whenever possible.

2x2 brick

24 tooth gear

1x4 plate

gray nail

axle (4-stud)

#5 Liftarm

bushing

1x8 beam


Engineering

Programming & Engineering ™

Engineering 2: LEGO Landers Overview: The students may have already noticed that one of the most vexing building challenges is finding ways to make the robot stay together. Nearly every LEGO Robotics enthusiast has a story of a time when a robot fell to pieces at a critical moment. In this activity students conduct a scientific investigation to determine the stability of five different building techniques. Then students can use the more successful techniques to improve the parts that they build for their robots.

Objective: Upon completion of this activity students will be able to . . . 1. DESCRIBE: how the scientific method can be used to improve robot performance. 2. UTILIZE: a variety of stability techniques during building sessions.

Time: 2 hours Materials: • • •

Copies of the LEGO Lander building instructions (one per team) Ziploc bags with presorted LEGO elements (see below) Class Chart (on chart paper or dry erase board)

Teacher Preparation: •

For this activity, each team will need a Ziploc Bag with the following elements:

8 x4

x2

9

x7

x2

x4

x12 7

x2

x16

x2

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Engineering

Programming & Engineering ™

After the students build the landers they will be dropping them. If possible, the teacher should identify a drop site such as a stairwell or window that will allow the students to drop the landers a considerable distance safely. If that is not possible, the teacher should specify a height, such as two meters, from which the landers will be dropped and mark the drop height with tape around the room. The teacher should create a class chart on a dry erase board or chart paper to match the one below. Lander A B C D E

Hypothesis

Successful

Unsuccessful

Warm-Up: Students make a hypothesis on the LEGO Lander worksheet in the Individual Logbook. Procedure: 1. The teacher should explain that in this activity the students will be using science to examine strategies for stability. Each team (or pair) will be building a set of five LEGO models, or landers, that were designed following two rules: • •

The lander must be at least 8 studs tall and 8 studs wide. The lander cannot include more than 15 elements.

After they are built, each lander will be dropped to test its ability to stay together after a fall. 2. The teacher should record each team’s hypothesis on the class chart. 3. Then the teacher should distribute the materials and should instruct the students to read the notes in the directions carefully as they are building. 4. When the groups are ready, the teacher can take the group to the drop site. The students drop the landers in an orderly fashion and tally the results on the class chart by counting the number of undamaged or successful landers and the number of damaged, unsuccessful landers. 5. The teacher should then examine the results with the class. Usually Lander E is the most successful. Why is this the case? Does that mean that the technique in Lander E is the best in all situations?

Assessment: Students should complete the Analysis and Conclusion questions on their Lunar Lander Worksheet.

Extension: The teacher can ask the students to design their own LEGO lander that follows these rules: • • •

The lander must be at least eight studs tall, eight studs wide and eight studs deep. The lander must contain more than 30 and less than 50 LEGO elements. Five of these elements must be bricks.

The students should test their completed landers by dropping them in the same way as the earlier landers.

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Answer Key

2

LEGO Lander Test

Warm Up: Make a Hypothesis

Today we’re going to test stability techniques using simple “LEGO Landers”. Look at the five lander designs below and in the instructions book. Make a hypothesis. Which lander will be most likely to survive a drop? Circle one and answer the question in complete sentences.

A

B

C

D

E

1. Why did you choose this lander?

Answers will vary. Students should have chosen a lander and provided a rational for their choice in complete sentences. The Experiment:

In the table below record how many landers survived the drop. Lander

How many landers survived the drop? (X)

What percentage of the landers survived the drop? (X ÷ Total Number of Landers × 100)

This should match the experimental data, but here is a sample..

A

B

C D E

0

0%

1 (out of five)

20%

1

20%

2

40%

5

100%


Analysis and Conclusion:

Answer the following questions in complete sentences. 1. Which lander was the most stable?

Usually the answer is E. 2. Why was this lander stable? Are there any techniques that were used in this landers that you could use in your robot?

Answers vary, but might include: this lander was light; this lander includes strong corner pieces. I might use axles and axle connectors in my next robot.

3. What techniques from other landers would you like to use in your robot?

Answers vary, but might include: the nailing technique in lander C of the use of liftarms in lander D might be useful. 4. Which lander was not stable?

Lander A is usually the least stable. 5. Why was this lander unstable? What lessons have you learned from these that you can use in your own robot?

Answers vary, but might include: stacking beams by the corners is not a strong design; I will build my robot using some of the ideas from the other landers.


Programming & Engineering ™

Engineering

Engineering 3: LEGO Roving Vehicles (LRV) Overview: In this activity students will build and race a vehicle that is powered by one motor. To win the race, students will need to discover how to use gears and pulleys to transfer motion.

Objective: Upon completion of this activity students will be able to . . . 1. UTILIZE: motors, gears and pulleys in their designs. 2. DISCUSS: how the size and arrangement of gears or pulley wheels effects movement.

Time: 2 hours Materials: • • • • • •

Copies of the LEGO Roving Vehicle building instructions (one per team) Box or sorting trays (one per team) LEGO elements (see building instructions) Masking tape Gearing Up CD-ROM Stopwatch

Teacher Preparation: • • •

Prepare the class collection of LEGO elements. The elements that the students will need for each car are listed in the instructions. Choose an area (usually in a hallway) for the final race. Use the masking tape to mark a starting line and finishing line. Download the program “LRV” from the Gearing Up CD-ROM into each NXT brick. Make sure that the NXT bricks are fully charged.

Warm-up: On the first day, a good warm up question would be,

“What variables effect how fast a LEGO Robot drives?” Possible answers could include, but are not limited to, programming, the wheels, the strength of the batteries, the weight and the arrangement of gears or pulleys. An additional warm-up is located on the Gearing Up CD-ROM in the file “activity2.ppt”. The correct answer is “B.”

Procedure: 1. After explaining the activity, the teacher distribute the sorting trays and directions to each team. 2. Highly motivated to win the race, each will quickly collect the elements for the LRV using the first page of the directions and their sorting tray. 3. Students should take turns building each step paying close attention to building strategies that they

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might need later. 4. As students finish, the teacher will help them attach a wire from Port A to the motor. Then students can test their robot by running the program called “LRV”. Since this is the first time that students have been asked to run a program, they may need assistance. 5. The students should try the different arrangements featured on the “Test and Refine Your LRV” worksheet. 6. The teacher should encourage students who complete this early to continue to test different modifications keeping in mind that the goal is to create the LRV that will win the class race. 7. When all groups have finished their LEGO Roving Vehicles, the teacher should lead them to the race site. 8. One student from each pair should stand on the starting line and the other should stand on the finish line. Then the teacher leads a countdown and on his/her mark the students start their robots. 9. The teacher should note the winners and repeat the race. 10. If time allows, the teacher can give the students time to prepare for a second race where pulleys are allowed, but gears are not permitted. 11. At the end of the activity, the teacher leads a discussion of the results of the races, paying close attention to how the arrangement of the gears or pulleys impacted the speed of the robot.

Assessment: Students complete the “LRV Racing Debrief” worksheet.

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3

Answer Key ™

Test and Refine Your LRV Design A

Design B

Design C

Answer the following questions in complete sentences. 1. Which design is the fastest?

B 2. Which design is the slowest?

A 3. Which design is the most powerful?

B 4. Design C uses a pulley. What are the advantages of this design?

Answers will vary, but might include: sometimes lining up gears is difficult, but a pulley is easy to align..

5. What are the disadvantages to Design C?

Answers will vary, but might include: pulleys tend to slip.


4

Answer Key ™

LRV Racing Debrief Answer the following questions in complete sentences. 8 tooth gear

1. The large gear in this image has 24 teeth and the smaller gear has 8 teeth. If the motor spin this 24-tooth gear around one time, how many times would the small gear spin?

3 times 24 tooth gear

2. If the motor spun the smaller 8-tooth gear around one time, how much would the larger 24-tooth gear spin?

1/3 of a spin Keeping this in mind, answer these questions.

A

B

C

Answers vary, but here are examples: 3. What are the advantages of design A? When would you want to use a design like this in your robot?

This design makes the robot drive slowly; this would be useful when I want to make my robot create a slow, powerful motion.

4. What are the advantages of design B? When would you want to use a design like this in your robot?

This design makes the robot drive quickly; this would be a great choice in a race for speed. 5. What are the advantages of design C? When would you want to use a design like this in your robot?

This might be a good design for a robot where slipping relieves additional tension on a part, such as in a robotic arm that runs into a solid object.


Programming & Engineering ™

Engineering

Engineering 4: Build the Basic Chassis Overview: The LEGO Roving Vehicles that the students built in the previous activity lacked the

ability to steer. The robots that the students build in this activity will be able to steer and will be used for the programming activities that follow. By building these robots, the students should have a better understanding of how they work and how to fix them if problems arise.

Objective: Upon completion of this activity students will be able to . . . 1. CREATE: a two-motor robot. 2. UTILIZE: a variety of LEGO elements in the building sessions.

Time: 2 hours Materials: • • •

Copies of the Basic Chassis building instructions (one per team) Box or sorting trays (one per team) LEGO elements (see building instructions)

Teacher Preparation: •

Prepare the class collection of LEGO elements. The elements that the students will need for each chassis are listed in the instructions.

Load the Mystery Programs (“One”, “Two”, “Three” and “Four” on the CD-ROM) into each team’s NXT.

Warm Up: A good warm-up question would be, “What were the disadvantages of the LEGO Roving Vehicle?” Answers might include that it could only drive forward and backward, it was top-heavy and that it lacked good places for attachments.

Procedure: 1. After explaining that the students will be building the robot that they will use for the programming challenges, the teacher should distribute the building instructions and sorting trays to each team. 2. Students should collect elements for the Basic Chassis using the first page of the directions and their sorting tray. 3. Students should take turns building each step paying close attention to building strategies that they might need later. 4. As students finish, they can test their creations using the numbered Mystery Programs.

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Section Three: Gearing Up for Programming Teaching students to program is a multi-step process. To be successful programmers students need to understand how to describe a robot’s behavior. They need to know what questions to ask. They need to learn how to think about programming. But, if the students begin by sitting immediately at the computer, they might learn how to operate the software, but they don’t always learn how to think. Gearing Up for Programming utilizes a process and manipulatives that allow the students to learn how to think first. In the process, the teachers load a mystery program onto each robot before class. The students then: •

OBSERVE the robot’s behavior looking for details about how it moves.

RECORD their observations in written descriptions.

REFINE their descriptions with the help of the teacher and other classmates. The complete descriptions will include all of the information needed to program the robot precisely.

TRANSLATE their descriptions into the NXT-G programming language. Each of the icons needed for the mystery programs is available in stamp form, so students merely stamp each icon and answer the important questions. If stamps are not available, teacher may choose to create custom stickers using the appropriate file on the CD-ROM.

NXT Programming The Common Palette

Move Icon Go Forward, Go Backward, Make a Wide Turn, Make a Sharp Turn, Stop

Move

Sound Icon Play a Note, Play a Sound File Play Sound

Display Icon Display an Image, Display Text, Draw, Clear the NXT Display Display

Wait Icon Wait for Time, Wait for Touch, Wait for Light/Dark, Wait for Sound, Wait for Distance

Wait for . . .

TEST their stamped programs by entering the programs into the computer. In this step students can focus on how to use the software; the program has already been written.

Loop Icon Repeat Forever, Repeat x Times, Repeat until Touch, Repeat until Loop

Light/Dark, Repeat until Sound, Repeat until Distance

If:

The mystery programs are designed to slowly Switch Icon Create Actions Based on a Condition (Time, Touch, introduce students to the programming Light/Dark, Sound, Distance) concepts they will need for a simple challenge. These include forward and backward motion, sharp turns and wide turns, utilizing sensors and utilizing the built-in rotation sensor. The file needed to create this poster is included on the These programs are available on the CD-ROM CD-ROM. or these can be recreated from the information on the next page. Condition

Else:

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Programming

Programming & Engineering ™

Mystery Program 1: Go forward two seconds; pause for one second; go backward for one second.

Ports: B & C Direction: Forward Steering: None Power: 75 Duration: 2 Seconds Next Action: Brake

Time: 1 Second

Ports: B & C Direction: Backward Steering: None Power: 75 Duration: 1 Second Next Action: Brake

Mystery Program 2:

Go forward 2 seconds; pause 1 second; make a wide left turn 2 seconds; pause 1 second; go forward 2 seconds.

Mystery Program 3:

Go forward 2 seconds; pause 1 second; make a sharp left turn 2 seconds; pause 1 second; go forward 2 seconds.

Ports: B & C Direction: Forward Steering: None Power: 50 Duration: 2 Seconds Next Action: Brake

Time: 1 Second

Time: 1 Second Ports: B & C Direction: Forward Steering: Left Power: 50 Duration: 2 Seconds Next Action: Brake

Ports: B & C Direction: Backward Steering: None Power: 50 Duration: 2 Seconds Next Action: Brake

Mystery Program 4: Go forward two seconds; make a sharp right turn; wait until the touch sensor is pressed; stop.

Ports: B & C Direction: Forward Steering: None Power: 75 Duration: 1 Second Next Action: Brake

Ports: B & C Direction: Forward Steering: Sharp Right Power: 75 Duration: Forever Next Action: Brake

Port: 1 Action: Pressed

Ports: B & C Direction: Stop Steering: Power: Duration: Next Action: Brake

24


Programming

Programming & Engineering ™

Programming 1a: Decipher Program One Overview: In the next three activities students observe the behavior of a pre-programmed robot,

record their observations, translate this into the programming language and then recreate the program on a computer. The process forces students to think critically about how the robot moves and prepares them to write more sophisticated programs. In this activity students examine a program involving forward and backward motion.

Objective: Upon completion of this activity students will be able to . . . 1. DESCRIBE: how the motors are used to create forward and backward motion. 2. RECREATE: a program that includes forward and backward motion.

Time: 1 hour Materials: • • • • • •

One robot chassis per team Copies of the “Decipher Program One” worksheet for each student Markers One set of icon stamps and one stamp pad per team Dry erase board Computer, LCD projector and CD-ROM (optional)

Teacher Preparation: •

If the students completed constructing the two-motor chassis, these robots can be used for this activity. If not, teachers will need to build, or arrange for students to build, one chassis for every robotics team.

Load the Mystery Programs (“One”, “Two”, “Three” and “Four”) into each team’s NXT (If these have not already been loaded). These programs are located on the CD-ROM.

Prepare the projector with the “Mystery Program” Power Point presentation (optional).

Procedure: 1. The teacher will start by giving each team a robot, marker and piece of paper. The teacher will then remind the students how to locate a program. This program is called “One”. • • • • • •

The orange button is “Yes”; the dark gray button is “no” and the triangles are used to see the available choices. Start by using the orange button to turn on the robot. Use the orange button to select “My Files”. Select “Software Files” Use the triangles to locate “One” Click on the orange button twice to rune program.

25


Programming & Engineering ™

Programming

2. Before the students start their robots, the teacher will instruct the students to watch the robot carefully. The students should write what they see on the first page of the “Decipher Program One” section of the student logbook. 3. After most groups have completed their descriptions, the teacher should ask groups to share their findings. As students share, the teacher will help the class increase the precision of the language and will keep a written record of the responses on the board. Here are some common student responses and teacher responses. The robot went forward.

The robot went forward for 20 cm.

The robot did go forward, but if you told your partner to go forward, he/she might walk across the room or all the way to Canada. How long did the robot go forward? That is a very precise description. In a later activity we’ll learn another way to program the robot that is related to distance, but in this case the robot was programmed to go forward for a certain number of seconds.

The robot went forward for two seconds.

The robot went forward for two seconds.

The robot went forward These are two of the correct steps, but there for 2 seconds and then is a third. Watch the robot again; what backward for one second. happens in between these two steps?

The robot goes forward for two seconds; it pauses for one second; the robot goes backward for one second.

One group claims, “The robot went forward for three seconds.” Another group claims, “The robot went forward for two seconds.”

The robot goes forward for two seconds.

How can we improve these results? We could use a stopwatch, or we could count very carefully saying “One, one thousand, two, one thousand . . .” Let’s all try these steps together.

4. After refining the description on the board, it should read, “The robot goes forward for two seconds; it pauses for one second; the robot goes backward for one second.” At this point the teacher could show the “Mystery Program” Power Point presentation. 5. The teacher should now instruct the students to copy the more precise description onto the back of their “Decipher Program One” worksheet. 6. The teacher should take a moment to introduce new vocabulary that describes the movement of the robot. The students have already talked about the direction of the motion, forward or backward, and the duration of the movement, 2 seconds or 1 second, but what other questions might a programmer need answered? The students might also answer that the programmer might want to know the speed of the robot. 7. The teacher should add that another question might be, “How does the robot move?’ The students might have already noticed that there are two motors in their robot. They can follow the wires on these wires to see that they are attached to ports B and C. Motors and other outputs can be attached to any of the lettered ports on the robot (A, B or C).

26


Programming

Programming & Engineering ™

8. Now the students are ready to begin translating their written description into the programming language. For this, each team will need two stamps, the Move and Wait for Time 9. The teacher will use the Power Point to guide the students through each step of the process. The students will one stamp for each box and will complete the boxes marked in the stamp. The finished program is shown below.

Move Stamp Wait for Time Stamp Move Stamp

75%

B&C

B&C

PORT

PORT

2 sec.

DIRECTION POWER DURATION

1 Second

75%

TIME

DIRECTION POWER DURATION

1 sec.

10. After the students have stamped the program, they’re ready to recreate the program on the computer. Scale 1:2 Finished Stamp 2.5” x 2.5”

Scale 1:2 Finished Stamp 2.5” x 2.5”

Scale 1:2 Finished Stamp 2.5” x 2.5”

27


Answer Key ™

5

Decipher Program One Today’s Activity:

When instructed, watch the robot. What do you see? Write a detailed description of the robot’s behavior in the box below:

The robot drives forward for two seconds, pauses for one second and drives backward for one second.


Step Two: Programming Stamp

Pause for one second.

Step Two: Written Description

Step Three: Programming Stamp

Go backward for one second.

Step Three: Written Description

2 sec.

Scale 1:2 Finished Stamp 2.5” x 2.5”

Scale 1:2 Finished Stamp 2.5” x 2.5”

DIRECTION POWER DURATION

TIME

Scale 1:2 Finished Stamp 2.5” x 2.5”

75%

1 Second

1 sec.

PORT

PORT

DIRECTION POWER DURATION

75%

B&C

B&C

Move Stamp Wait for Time Stamp Move Stamp

Step One: Programming Stamp

Go forward for two seconds.

Step One: Written Description

Answer Key


Programming & Engineering ™

Programming

Programming 1b: Recreate Program One Overview: Now that the students have learned the syntax of the programming language away from

the computer, they should be ready to focus on the mechanics of the software when they start using the computer.

Objective: Upon completion of this activity students will be able to . . . 1. WRITE: programs that utilize the move icon to move forward and backward.

Time: 1 hour Materials: • • • • • •

One robot chassis per team One USB cable per team Completed copies of the “Decipher Program One” worksheet Computers for each student (ideally) Computer with LCD projector Copies of the “Recreate Program One” instructions (in the Constructopedia, optional)

Teacher Preparation: •

Load the LEGO Education software onto each computer. Be prepared to describe how the students will access the software on those particular computers.

Warm Up: Generally the warm-up for this lesson is a review of teacher expectations for computer

use. Rules might include information about which applications students may use during robotics, how to handle laptop computers or how to shutdown computers at the end of the session.

Procedure: The goal of this activity is to teach all of the students how to write a program in NXT-G on the computer. There are at least two different ways to do this. For most groups the teacher should guide the whole class through the process step-by-step. In this method the teacher will describe the step, a student seated at the computer with the LCD projector will demonstrate the step and then the other students will copy the step. The steps are outlined in the Constructopedia. Alternately, teachers may choose to copy these directions for each group. Students can then work through these steps at their own pace, asking for help when necessary. Since the teacher in this option spends his/her time helping individual students with problems, this is only a good option for small groups or groups that are already technologically advanced. At the end of the session every student should have experienced success programming a robot. Advanced students may have also had time to experiment with their own programs.

30


Programming

Programming & Engineering ™

Programming 2: Turns Overview: The next two mystery programs are both left turns, but two different types of turns. In

program two the turn is a wide turn, a turn created by making one track move faster than the other. In program three the turn is a sharp turn, a turn created by making one track go forward and the other go backward. Often programmers using the NXT-G software do not realize this because programming a turn is quite simple; this activity is designed to teach these differences.

Objective: Upon completion of this activity students will be able to . . . 1. DESCRIBE: how the motors are used to create wide and sharp turns. 2. RECREATE: programs that includes wide and sharp turns.

Time: 2 hours Materials: • • • • •

One robot chassis per team Pieces of butcher paper for each team Markers (two per team, different colors) One set of icon stamps and one stamp pad per team Dry erase board

Teacher Preparation: •

If the students completed constructing the two-motor chassis, these robots can be used for this activity. If not, teachers will need to build, or arrange for students to build, one chassis for every robotics team.

Load the Mystery Programs (“One”, “Two”, “Three” and “Four”) into each team’s NXT (If these have not already been loaded). These programs are located on the CD-ROM.

Procedure: 1. The teacher should start by asking the students to observe the behavior of the robot as they run the program called “Two”. The students should write what they see happening on the top of their butcher paper. 2. The teacher should ask the students to share their written descriptions. As the students share, the teacher can ask for clarification and can write the complete description on the board. This should read, “The robot drives forward for two seconds. It pauses for one second. It turns left for two seconds. It pauses for one second. It goes forward for two seconds and stops.” 3. After the students agree on a description, the teacher should ask the students to run the program called “Three”. The students should notice that the same written description could apply to this program, but that the turn is different. The first is called a wide turn. The second is called a sharp turn.

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Programming

Programming & Engineering ™

Move Stamp PORT

DIRECTION POWER DURATION

Scale 1:2 Finished Stamp 2.5” x 2.5”

Wait for Time StampMove Stamp Wait for Time Stamp PORT

TIME

TIME

DIRECTION POWER DURATION

Scale 1:2 Finished Stamp 2.5” x 2.5”

Scale 1:2 Finished Stamp 2.5” x 2.5”

Scale 1:2 Finished Stamp 2.5” x 2.5”

Move Stamp PORT

DIRECTION POWER DURATION

Scale 1:2 Finished Stamp 2.5” x 2.5”

The students start with the robot in the lower right corner.

At each pause in the program, the students draw a box.

Then the students stamp the icons in the appropriate places in the path of the robot.

4. Now, to see the difference, the students will map the turns on their butcher paper. The teacher should demonstrate how the students will place their robot in the lower right corner of the paper. The teacher will trace the robot with the marker. Then as the teacher runs program “Two”, he/she will demonstrate how to trace the robot after each step. The teacher can instruct the students to stop and restart their robot if necessary. 5. The students will complete the same process. As they finish, they should then stamp the icons of the program in the appropriate places. The program is depicted below. In the step with the turn, the teacher should instruct the students to leave the direction box in the third icon, the one controlling the turn, empty. 6. The students should now run program “Three” on the same butcher paper. Using a different marker, they should mark the path of the robot running the same program with a sharp turn. 7. The students should add the icons for the forth and fifth steps in the new path (the other icons are the same. 8. The teacher should work with the students to create curved arrows that differentiate between wide turns and sharp turns. The students can add these to their program in the empty box in the third icon. 9. The teacher can finish this lesson by leading a discussion about when students might want to use wide turns and when they might want to use sharp turns. Students can test their theories as they try to recreate both programs on the computer.

Move Stamp Move Stamp Move Stamp Wait for Time Stamp Wait for Time Stamp

50%

B&C

B&C

B&C

PORT

PORT

PORT

2 sec.

DIRECTION POWER DURATION

1 Second

50%

TIME

DIRECTION POWER DURATION

2 sec.

1 Second

50%

TIME

DIRECTION POWER DURATION

2 sec.

32 Scale 1:2 Finished Stamp 2.5” x 2.5”

Scale 1:2 Finished Stamp 2.5” x 2.5”

Scale 1:2 Finished Stamp 2.5” x 2.5”

Scale 1:2 Finished Stamp 2.5” x 2.5”

Scale 1:2 Finished Stamp 2.5” x 2.5”


Programming

Programming & Engineering ™

Programming 3: Inputs and Outputs Overview: Thus far the students have been programming outputs, the motors that they use to control

the robot. This activity includes two activities that teach them how to use inputs to program the robot to react to its environment. In the first activity the students decipher a mystery program that includes the touch sensor. In the second the students complete a short challenge involving the light sensor.

Objective: Upon completion of this activity students will be able to . . . 1. DEFINE: input and output. 2. CREATE: programs that use touch and light sensors.

Time: 2 hours Materials: • • • • • • • •

One robot chassis per team One touch sensor/cord per team Pieces of legal-sized paper One set of icon stamps and one stamp pad per team Dry erase board A lightly colored surface Black electrical tape Copies of the “Inputs and Outputs: Program Four” worksheet for every student

Teacher Preparation: •

If the students completed constructing the two-motor chassis, these robots can be used for this activity. If not, teachers will need to build, or arrange for students to build, one chassis for every robotics team.

Load the Mystery Programs (“One”, “Two”, “Three” and “Four”) into each team’s NXT (If these have not already been loaded). These programs are located on the CD-ROM.

Use the electrical tape to create a box a few inches larger than the robot and a black line several feet away (see image). .

Electrical Tape

Warm Up: The question on the worksheet asks the students to place the

following items into two categories: Mouse, Printer, Keyboard, Monitor, Camera There are several possible answers to this question. The students might choose to categorize the items by size, price or color. But hopefully some students will see that some of these devices, the computer mouse, keyboard and camera, are used to send information into the computer. These are called inputs. The other items are controlled by the computer; that is, the information is going out of the computer into the devices. These devices, the printer and monitor, are called outputs. These terms are important to

33


Programming & Engineering ™

Programming

understanding the two activities that follow.

Procedure (Part One): 1. The teacher will begin by distributing the supplies, including a touch sensor to each group. The teacher can explain that the touch sensor can be used to tell the NXT brick if it is pushed, bumped or released. The teacher can ask the students, “Is the touch sensor an input or an output?” 2. The answer is input. This is important because it determines where the touch sensor should be attached. Inputs are attached to the numbered ports, 1, 2, 3 and 4. The teacher should instruct the students to attach their touch sensor to port 1. 3. Now the students are ready to run program “Four”. The teacher should tell them that one step of the program involves the touch sensor. Then the students should write a description of what they see happening on their papers. 4. As students finish, the teacher can help them to refine their descriptions on the dry erase board. A precise description might be, “Motors B and C go forward for one second. Motors B and C create a sharp right turn forever. The NXT waits for the touch sensor on port 1 to be pressed. Ports B and C stop.” Notice that this particular description includes a sentence for each step. 5. The students are now ready to stamp the program. There are several new concepts here that the teacher should explain. •

In the second step, “Motors B and C create a sharp left turn forever”, the duration is “forever”. The students might also choose to represent this with the ∞ symbol. This does not actually mean that the motors will run forever; it tells the robot to run the motors until the program indicates otherwise.

In the third step the students will use the Wait for Touch stamp for the first time. They should record the port, “1”, and the action, “Wait for Push”. The action can also be “Wait for Release” or “Wait for Bump”.

In the fourth step the students will use the Move Icon to stop the motors. They do this by choosing “Stop” for the direction. They can do this by either writing the word “stop” or drawing a circle with a line through the middle ( ).

6. After checking their work, the teacher should allow the students to recreate the program on the computer, download it to the robot and test their results.

Procedure (Part Two): 1. As students complete the activity with the touch sensor, they can begin to decipher the light sensor challenge. The teacher should inform the students that the light sensor is an input that can tell the robot the amount of light reflected by a surface. Since it is an input, it should be attached to a numbered port on the robot. If the students also attach the light sensor so that the “eye” is facing the table, it will be able to detect the white and black lines.

Black Line Base

2. As more groups begin this mini-challenge, more groups will be asking questions. At an appropriate point the teacher can stop the class to provide

34


Programming

Programming & Engineering ™

helpful hints. One essential hint is to learn to see what the light sensor is “seeing”. The light sensor reports the amount of light or dark to the NXT as a number between 0 and 100. To see this value the students should follow these steps: • • • •

Turn on the NXT (or return to the main menu). Use the triangle buttons to locate “View”. Select this with the orange button. Then locate and select “Reflected Light”. Locate and select the correct port for the light sensor.

3. The teacher should instruct the students to find the value for the surface of the table and for the black line. The students should record these values on a scrap of paper. 4. Using the “Mystery Program” power point or a stamp as a visual aid, the teacher should explain how the light sensor operates. After supplying a number for the port box, the students will need to describe the level of light that the robot is seeking. Suppose that the table surface measured 53% and the black tape measured 33%. The students should start by selecting a value between these two; in this case 43% would be a good choice. The students can either tell the robot to seek a number greater than 43 or less. Since the students are starting on the table surface (53%) and are seeking the black line (33%), they should tell the robot to wait until the light sensor detects a value that is less than 43.

B, C

75% 1 sec.

75%

B, C

2

8

5. It is likely that the students will also discover other problems during this exercise, including that the box itself is a black line. The students should discover their own solutions with guidance from the teacher. One possible solution is included below.

< 43

B, C

Assessment: One excellent way to test the student’s ability to use sensors is in a mini-competition

where students can earn points by using a sensor to accomplish an objective. For instance, in the basketball challenge provided on the CD-ROM, the students can earn points by using a light sensor or touch sensor to locate the basket. In this particular challenge students can also earn points by making a basket. (If the elements that are needed for the basketball hoops aren’t available, plastic cups are a good substitute.) A worksheet asking students to identify inputs and outputs for the NXT has also been provided in the student logbook.

35


6

Answer Key ™

Inputs and Outputs: Program Four Warm-Up:

Place the following items into two categories.

Mouse Category 1: Category 2:

Printer

Keyboard

Monitor

Camera

Answers here will vary, but hopefully a few students will group the inputs (the mouse, keyboard and camera) and outputs (the printer and monitor) seperately.

How did you choose your categories?

Decipher the Mystery Program: Run program “Four”. Write a detailed description of what you see happening in the box below.

The robot drives forward for one second. The robot starts making a sharp right turn. The robot waits until the touch sensor is pushed and then stops.


B&C PORT

1 PORT

Wait for Push

Step Two: Programming Stamp

B&C PORT

75% forever

B&C

PORT

Step Four: Programming Stamp

1 sec.

Scale 1:2 Finished Stamp 2.5” x 2.5”

DIRECTION POWER DURATION

Scale 1:2 Finished Stamp 2.5” x 2.5”

DIRECTION POWER DURATION

75%

Scale 1:2 Finished Stamp 2.5” x 2.5”

DIRECTION POWER DURATION

Scale 1:2 Finished Stamp 2.5” x 2.5”

ACTION

Move Stamp Move StampWait for Touch Move Stamp

Step Three: Programming Stamp

Motors B and C stop.

Step One: Programming Stamp

The NXT waits for the touch sensor to be pressed.

Motors B and C create a sharp right turn forever.

Step Four: Written Description

Motors B and C go forward for one second.

Step Three: Written Description

Step Two: Written Description

Step One: Written Description


Programming & Engineering ™

Programming

Programming 4: Graphing and the Rotation Sensor Overview: In the preceding activities the students used time to describe the duration of each step

in their programs. This is a smart choice when trying to decipher mystery programs, but it is not the smartest choice when trying to program the robot to win competitions. Time is partially dependant on battery power. With a weak battery the robot may only drive a few feet in two seconds, but a fully charged robot might drive a yard in the same number of seconds. The solution is to teach students to use rotations of the motor instead of time to describe the duration of each step. Thus, “Go forward for two seconds,” becomes “Go forward for x rotations.”

If you tell your robot to drive forward for two seconds, it might only go this far if the batteries are weak.

If you tell your robot to drive forward for two seconds, it might go this far if the batteries are fully charged.

The solution is a sensor in the motor that counts how many times it turns.

The new problem for the programmers is knowing how many rotations to choose. So in this activity the students will gather data about the performance of their robot and will organize that data in a graph.

Objective: Upon completion of this activity students will be able to . . . 1. UTILIZE: rotation sensors in their programs. 2. DESCRIBE: how engineers gather and analyze data to improve their creations.

Time: 2 hours Materials: • • • • •

One robot chassis per team One meterstick per team One calculator per team Copies of the “NXT Input and Output”, “Class Data Table”, “Graphing and the Rotation Sensor” Worksheet for every student Computer and LCD projector (Document Camera optional)

Teacher Preparation: •

Prepare all materials and prepare a class chart (see step four).

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Programming

Programming & Engineering ™

Procedure:

NXT Progra

1. During the warm up the students should have noticed that the NXT motors can be used as an output or an input. The teacher should take a moment to explain why using the motors to count the number of rotations is a more reliable method for programming than using time (See overview). The teacher should also explain that the students will be collecting and organizing data about this new sensor and their robot to make programming easier in the future.

The Common Palette

2. Then the teacher should demonstrate how students will program and take data about the robot. To begin, the teacher should show the program on the right on an LCD projector. Accuracy in programming will be very important to accuracy in the class data. The teacher can show that using the rotation sensor is as easy as selecting “rotations” instead of “seconds” in the duration box. 3. Then the teacher should load the program into the robot and demonstrate how the students should measure the distance that the robot travels. The teacher should emphasize that the students start the robot with the front of the track on the zero of the metric scale on the meter stick. Then they run the program. After the program they should read the value from the front of the track.

Move

Go Forward, G Turn, Stop

Move

Ports: B & C Direction: Forward Steering: None Power: 75 Duration: x rotations Next Action: Brake

Sound

Play a Note, Pla

Play Sound

4. Next the teacher should assign each team a number of rotations to test. One way to do this is to use a document camera and a copy of the “Class Data Table” worksheet. The teacher can then write the name of the team testing a particular value in the box in small letters. Since each value will be tested Display an Ima Display three times, there should be plenty of values for every group.

Displa

5. The students should each test their value. As they do, they can record their answer on the class chart under the document camera. The teacher can then assign them an additional number to test. 6. When all of the values have been collected, the teacher should lead a discussion about the class findings. First, the students should examine the data to see if their are any outliers. These should be eliminated or retested. Wait for . . .

Wait Ic

Wait for Time, W Wait for Distan

7. Then teacher should instruct the students to find the mean for each row of data, checking the answers after this process to ensure that all teams have accurate values. Teachers may choose to allow the students to use calculators for this step. 8. Finally, the students can use the data in the first and final columns to create a graph on the “Rotations v. Distance Graph” worksheet.

Extension: Loop

Ask the students to compete in a programming race. In the race teams will race to create programs to produce certain behaviors. A list of behaviors follows. Many of these require the students to use their graphs to determine the correct number of rotations. The teacher will announce the first of these to the entire class. The students will begin racing to program and test that particular program. After a team demonstrates that behavior with their robot, the teacher will reveal the next behavior on the list to that team. Team members should switch who has control of the computer each time that they attemptIf:to program a new behavior. The first team to complete the entire list is the winner.

Condition

39 Else:

Loop

Repeat Foreve Light/Dark, Re

Sw

Create A Light/D


7

Answer Key ™

NXT Inputs and Outputs For each of the following, write ”Input” or “Output”. Remember that an input sends information into the NXT and the NXT sends information to an output. Image

What does this do?

Is this an input or output?

Motor The NXT can tell motors to turn on or off.

Output

Motor The motors can tell the NXT how many times they’ve spun.

Input

Touch Sensor The touch sensor tells the NXT if it has been pushed.

Input

Light Sensor The Light Sensor tells the NXT how much light is reflected by a surface (so it will know if the table is black or white).

Input

Sound Sensor The sound sensor tells the NXT how loud it is in the room.

Input

Distance Sensor The distance sensor tells the NXT how far the robot is from the nearest object. Lamp The NXT tells this LEGO light bulb when to light and when to turn off.

Input

Output


8 ™

Class Data Table Copy the data from the class table into this table. Rotations

1 2 3 4 5 6 7 8

Distance Trial 1

Distance Trial 2

Distance Trial 3

Mean Distance


9 ™

Graph of Rotations v. Distance Use the data from the class chart to create a graph of distance v. rotations. 100

90

Distance Travelled (Measured in Centimeters)

80

70

60

50

40

30

20

10

0

0

1

2

3

4

5

Number of Rotations

6

7

8


™

Programming Relay List

1. Go Forward for 2 Seconds. 2. Go Forward for 2 Rotations. 3. Go Forward for 40 centimeters. 4. Go Forward for 80 centimeters. 5. Go Forward for 80 centimeters. Make a sharp right turn for 1 rotation. 6. Go Forward for 80 centimeters. Make a sharp right turn for 1 rotation. Go Forward for 60 centimeters. 7. Go Backward for 60 centimeters.

Gearing Up for Programming and Engineering - p. 43


Programming & Engineering ™

The Next Challenge

Section Four: The Next Challenge The Gearing Up for Programming and Engineering activities were designed to prepare students to participate in a challenge or demonstration. Here are some suggestions for future robotics activities. •

The FIRST LEGO League (FLL): Each year the FIRST LEGO League creates a robotics challenge for students around the world. The challenge is built around a science or technology theme, such as Mars, nanotechnology or alternative energy. The robotics portion of the competition involves a standardized competition table with several LEGO models. Students work together in teams of no more than ten students to create a robot that can complete several missions during a timed performance round. A research project compliments the robotics challenge. On competition day students compete against many other teams in a competition with as much energy and excitement as any athletic event. Teams are scored on the performance of their robot, their ability to discuss their design, their research presentation and teamwork. FIRST LEGO League season generally starts in late August and ends with competitions in December or January. Visit www.firstlegoleague.org for more information.

School/Class Competitions: Schools or classrooms often adapt the rules of the FIRST LEGO League for their own competitions. This is a great opportunity to invite parents to celebrate their students’ work. Future Gearing Up series will offer ready-made challenges and curriculum for teachers who choose this option.

The Robotics Fair: Some teachers might prefer to sponsor a class robotics fair where each group has designed a robot to fit a particular theme. This appeals to less competitive students by allowing them the freedom to design a robot that they would like to design. This usually requires smaller class sizes, careful management or additional help. The results can be impressive. A previous robotics fair included robots that sang, danced, told the time, scared intruders and composed poetry.

Mini-Challenges: The simplest and most cost effective option is to create a small challenge for the class to complete with their robots. Students can start with the basic chassis from these activities and modify it to complete a series of tasks. For instance, one mini-challenge asked students to create a robot that could play basketball. Students had to engineer a part to throw the balls that are part of the Base Kit into a small hoop. The hoops were arranged on a table. The students had to program their robot to drive to different hoops to make the shot. Some of the hoops were located near black lines to encourage the use of the light sensor and walls to encourage the use of the touch sensor. Students earned points for each different hoop or subassembly that they utilized successfully.

44


The Next Challenge

Programming & Engineering ™

Additional Information Check out the CD-ROM that accompanies this manual for these useful documents: •

PDF versions of these lesson plans, the Constructopedia and the Student Logbook

PDF files that can be used to print large posters of “Common LEGO Elements”, the “Design Cycle” and “NXT-G Programming”

A dictionary that provides an exhaustive list of LEGO elements and their names

The Power Point files mentioned in this text, including one used to review element names and another used to review the mystery programs

Instructions for the LEGO Stick Game, an active way to practice the nailing technique, and LEGO Element Bingo, a way to review element nomenclature.

The mystery programs and the program for the LRV activity

Guides for NXT-G programming

Image files for common elements and NXT-G icons

A PDF file that can be used to print programming icon stickers

Instructions for the Basketball Challenge

Homemade video introductions to Bits and Pieces, the extension of the LEGO Lander activity, Deciphering the Mystery Programs and using a Light Sensor.

Building instructions for Crawlers, two models that allow students to compare and contrast the use of pulleys with the use of the worm gear.

Documentation from FLL including directions for an FLL table and scoring rubrics.

Ideas for additional LEGO robotics activities including using the sound sensor, using the display icon and creating a remote control.

One of two Crawlers

L-E-G-O Game

These websites might also be useful: •

www.legoeducation.com LEGO Education, administered by PITSCO®, is the place to shop for all LEGO Education kits and software.

www.hightechkids.org High Tech Kids is the place for information about FIRST LEGO League competitions in Minnesota, but it also has information of interest to any competitors.

www.legoengineering.com This site was created by the active engineering education department at Tufts University. It includes multiple must-have downloads and curriculum ideas.

45


S tudent Logbook Name: __________________ Class Period: _____________

™


1 ™

Name That Element

Write the name of each element in the space provided. Be sure to include the size whenever possible.


2 ™

LEGO Lander Test

Warm Up: Make a Hypothesis

Today we’re going to test stability techniques using simple “LEGO Landers”. Look at the five lander designs below and in the instructions book. Make a hypothesis. Which lander will be most likely to survive a drop? Circle one and answer the question in complete sentences.

A

B

C

D

E

1. Why did you choose this lander?

The Experiment:

In the table below record how many landers survived the drop. Lander

A

B

C D E

How many landers survived the drop? (X)

What percentage of the landers survived the drop? (X ÷ Total Number of Landers × 100)


Analysis and Conclusion:

Answer the following questions in complete sentences. 1. Which lander was the most stable?

2. Why was this lander stable? Are there any techniques that were used in this landers that you could use in your robot?

3. What techniques from other landers would you like to use in your robot?

4. Which lander was not stable?

5. Why was this lander unstable? What lessons have you learned from these that you can use in your own robot?


3 ™

Test and Refine Your LRV Design A

Design B

Answer the following questions in complete sentences. 1. Which design is the fastest?

2. Which design is the slowest?

3. Which design is the most powerful?

4. Design C uses a pulley. What are the advantages of this design?

5. What are the disadvantages to Design C?

Design C


4 LRV Racing Debrief

™

Answer the following questions in complete sentences. 8 tooth gear

1. The large gear in this image has 24 teeth and the smaller gear has 8 teeth. If the motor spin this 24-tooth gear around one time, how many times would the small gear spin?

24 tooth gear

2. If the motor spun the smaller 8-tooth gear around one time, how much would the larger 24-tooth gear spin?

Keeping this in mind, answer these questions.

A

B

C

3. What are the advantages of design A? When would you want to use a design like this in your robot?

4. What are the advantages of design B? When would you want to use a design like this in your robot?

5. What are the advantages of design C? When would you want to use a design like this in your robot?


5 ™

Decipher Program One Today’s Activity:

When instructed, watch the robot. What do you see? Write a detailed description of the robot’s behavior in the box below:


Step Two: Written Description

Step Two: Programming Stamp

Step One: Written Description

Step One: Programming Stamp

Step Three: Programming Stamp

Step Three: Written Description

™


6 ™

Inputs and Outputs: Program Four Warm-Up:

Place the following items into two categories.

Mouse

Printer

Keyboard

Monitor

Camera

Category 1: Category 2:

How did you choose your categories?

Decipher the Mystery Program: Run program “Four”. Write a detailed description of what you see happening in the box below.


Step Two: Written Description

Step Two: Programming Stamp

Step One: Written Description

Step One: Programming Stamp

Step Three: Programming Stamp

Step Three: Written Description

Step Four: Programming Stamp

Step Four: Written Description


7 ™

NXT Inputs and Outputs For each of the following, write ”Input” or “Output”. Remember that an input sends information into the NXT and the NXT sends information to an output. Image

What does this do? Motor The NXT can tell motors to turn on or off.

Motor The motors can tell the NXT how many times they’ve spun. Touch Sensor The touch sensor tells the NXT if it has been pushed. Light Sensor The Light Sensor tells the NXT how much light is reflected by a surface (so it will know if the table is black or white). Sound Sensor The sound sensor tells the NXT how loud it is in the room. Distance Sensor The distance sensor tells the NXT how far the robot is from the nearest object. Lamp The NXT tells this LEGO light bulb when to light and when to turn off.

Is this an input or output?


8 ™

Class Data Table Copy the data from the class table into this table. Rotations

1 2 3 4 5 6 7 8

Distance Trial 1

Distance Trial 2

Distance Trial 3

Mean Distance


9 ™

Graph of Rotations v. Distance Use the data from the class chart to create a graph of distance v. rotations. 100

90

Distance Travelled (Measured in Centimeters)

80

70

60

50

40

30

20

10

0

0

1

2

3

4

5

Number of Rotations

6

7

8


C onstructopedia

™


Bits and Pieces B Element Inventory (Student Copy))

™

Beams

Axles

16

4

x1

3.5

x1

x1 8 Gears

x2

4

x1

x1

x1

Plates Nails x1

x6

x1

Parts for the Pulley x1 x1

Liftarms

x1

x1 x1

3

x1

Gearing Up for Programming and Engineering - p. 60


Bits and Pieces B Building Instructions (Teacher Copy)

™

1. 8 x1 Start with a 1x8 beam.

2. x2 Add black nails in the first and last holes of the beam. Count from the left. The end of the nails should be facing the builder.

3. 16 x1 Use the nails to attach a 1x16 beam to the model. The left edge of this beam should match the left edge of the 1x8 beam. This nailing technique helps builders to make strong models.

4. 8 x1

4

x1 x2

Try adding a 1x8 beam above the 1x16 beam. Add a nail to the top and bottom layers and then try to add a beam. Notice that the holes don’t align.

Gearing Up for Programming and Engineering - p. 61


5.

There is a nailing technique that can be used with stacked beams, but it requires the builder to know how to properly space the holes. Remove the four elements that were added in the previous step.

6. x1 Add a 2x8 plate with holes to the top of the 1x8 and 1x16 beams.

7. x1 Add a 1x8 plate on top of the 2x8 plate on the same side as the 1x16 beam.

8. x1 Finally, add another 1x8 beam above the 1x8 plate. Notice that there are two layers of plates in between the two beams. Gearing Up for Programming and Engineering - p. 62


9. x4

Place black nails in the second and sixth holes of the 1x8 beam and directly below in the 1x16 beam.

10. 4

x1

Use a 1x4 beam to connect the two nails on the right side of the model.

11. 3

x1

Use a #3 liftarm to connect the two holes on the left side of the model. These are two ways to use the nailing technique with stacked beams.

12. x1 An axle nail is a useful element since one end is an axle and the other is a nail. Now add an axle nail to the model in the eighth hole of the 1x16 beam. Use the nail end.

Gearing Up for Programming and Engineering - p. 63


13.

x1 Add an eight-tooth gear to the axle end of the axle-nail.

14. 4

x1

Place and hold a #4 axle in the twelfth hole of the of the 1x16 beam.

15. x1 Add the 40-tooth gear on the front of the #4 axle. The two gears should engage so that one turns the other.

16.

x1 Turn the model 180 degrees so that the back is now the front. Then add a half bushing (also known as a small pulley wheel) to the other end of the #4 axle.

Gearing Up for Programming and Engineering - p. 64


17. 3.5

x1

Now find the 3.5 stud-long axle with the stop. Add this axle to the first hole of the 1x16 beam with the stop on the back of the beam. Notice how the stop helps to hold the axle in place.

18. x1 Add a medium pulley wheel to the front of the new axle.

19. x1 Stretch a band between the two pulley wheels to create a pulley.

Gearing Up for Programming and Engineering - p. 65


20. x1

Now add the liftarm with a double-bend to one axle and then the other. Investigate how the pulley and gears operate.

Gearing Up for Programming and Engineering - p. 66


LEGO Lander Experiment

Lander A

™

For this first lander simply stack seven 1x6 beams as shown in the picture.

1.

x7

Gearing Up for Programming and Engineering - p. 67


LEGO Lander Experiment

™

Lander B

For this lander stack seven 1x8 beams as shown.

1.

x7

Gearing Up for Programming and Engineering - p. 68


LEGO Lander Experiment

™

Lander C

1. x2

x2 Find two 1x8 beams and two nails. Build the model shown above.

2.

Try to use a 1x8 beam to lock these layers together. Notice that this doesn’t work.

3. x1

The way to fix this is to add a bit of space between the two beams using plates. Try changing your model by adding one 1x8 plate between the two layers. Try locking the two layers together now. Was Gearing Up for Programming and Engineering - p. 69 one plate enough space? Try adding another.


4. x1

x1 Notice that the number of plates to put between each layer of beams is TWO. If you remember to always place two plates between each layer of beams parts will line up more easily. I like to call this technique the stack technique.

5. x2

6. x1

Gearing Up for Programming and Engineering - p. 70


7. x2

8. x1

Gearing Up for Programming and Engineering - p. 71


LEGO Lander Experiment

Lander D

™

You could build a simple lander with liftarms as shown in the first picture, but it would be very floppy and unstable. Instead, build the one shown in the directions.

1. x1

9

x1

x1

7

2. x10

Gearing Up for Programming and Engineering - p. 72


3. x1

9

x1

7

x1

Gearing Up for Programming and Engineering - p. 73


LEGO Lander Experiment

Lander E

™

Construct this lightweight lander with axles and axle connectors.

1. 8 x4

x4

Gearing Up for Programming and Engineering - p. 74


The LEGO Roving Vehicle Element Inventory

™

15

x4 x1 x6 x2 Motor

x3 6

x1

x24

x2

x2 4

x2

x5 x4

x4

12 x2 8

x4

x1 2

x4

x1 x4 x1 Gearing Up for Programming and Engineering - p. 75


The LEGO Roving Vehicle Building Instructions

™

1. Motor

x1 Long Nail

x3

2. 3

x2

3. 8 x1 x2

Gearing Up for Programming and Engineering - p. 76


4.

5. x2 x2 x2

x2

Gearing Up for Programming and Engineering - p. 77


6.

7.

1.

2.

3. 6

4

x1

x1

x2

Gearing Up for Programming and Engineering - p. 78


8.

x4

9. 15

x1

Gearing Up for Programming and Engineering - p. 79


10. x6 15

x1

x2

2

#2 Axle

Joiner

x2

x2

1.

4.

2.

5.

3.

Gearing Up for Programming and Engineering - p. 80


11.

Gearing Up for Programming and Engineering - p. 81


12.

1.

2.

3.

4 6

x1

x1 x2

13.

x4

Gearing Up for Programming and Engineering - p. 82


14. 15

x1

15. x6 15

x1

x2

1.

2

x2

x2

2.

Gearing Up for Programming and Engineering - p. 83


3.

5.

4.

Gearing Up for Programming and Engineering - p. 84


16.

17. 12 x2

Gearing Up for Programming and Engineering - p. 85


18. x1

x1

19.

Gearing Up for Programming and Engineering - p. 86


20.

21.

x3

x4

Half Bushing

Gearing Up for Programming and Engineering - p. 87


22.

x4

Gearing Up for Programming and Engineering - p. 88


23.

x1

Add a wire connecting the motor to port A.

Gearing Up for Programming and Engineering - p. 89


Basic Chassis Element Inventory

™

16

x3

x4

4

x1

8

x2 11

5.5

x2 x1

x2 9

5

3

2

x1

x3 x1

7

x2

x4

x4 x2 x8 x22

x2

x2

x2 x2 x6 x2 x4

x4 x2

x4

Gearing Up for Programming and Engineering - p. 90


Basic Chassis Building Instructions

™

1. 16

x1 3

2.

x2

5

x2

x1

x2

x1

x2

x2

3. x1 x2

Gearing Up for Programming and Engineering - p. 91


4. 5

x1

x1

5. x1

6. x1

x2

Gearing Up for Programming and Engineering - p. 92


7.

x2

8.

9. x4

Gearing Up for Programming and Engineering - p. 93


10.

9 x1

11.

12.

Gearing Up for Programming and Engineering - p. 94


13. x2

14. x1

15. 5

x1

x1

Gearing Up for Programming and Engineering - p. 95


16. x1

17. x1

18.

Gearing Up for Programming and Engineering - p. 96


19. x2

x4

x4

20. 7 x2

21. x4

Gearing Up for Programming and Engineering - p. 97


22. x2

23. 11 x1

2

x2

Gearing Up for Programming and Engineering - p. 98


24.

25.

x3

Gearing Up for Programming and Engineering - p. 99


26.

1.

2.

3. x1 4

x2 x2

27. 8

x1 x2

Gearing Up for Programming and Engineering - p. 100


28. 1.

16

x1

5.5

x1 x1

2.

Gearing Up for Programming and Engineering - p. 101


29. x1

30. x2

Gearing Up for Programming and Engineering - p. 102


31.

32.

x3

Gearing Up for Programming and Engineering - p. 103


33. 1.

2.

3.

x1 x2 x2

34. 8

x1 x2

Gearing Up for Programming and Engineering - p. 104


35. 1.

16

5.5

x1 x1

2.

Gearing Up for Programming and Engineering - p. 105


36. x1

37. x2

Gearing Up for Programming and Engineering - p. 106


38.

x1

x2

Use a wire to attach this motor to Port B.

Use a wire to attach this motor to Port C.

Gearing Up for Programming and Engineering - p. 107


Basic Motor Mount ™

1. Motor

x1 Long Nail

x3

2. 3

x2

3. x3

x1

Gearing Up for Programming and Engineering - p. 108


4. x1

x1

5.

6 x1 x1

6. 16

x1

Gearing Up for Programming and Engineering - p. 109


7.

Here are three different options for the last step. Think about . . . • Which makes the arm move the fastest? • Which makes the arm the strongest? • Which makes the arm able to slip when needed? Choose the design that suits your needs or create your own.

Gearing Up for Programming and Engineering - p. 110


Recreate Program One

1. Open the “LEGO MINDSTORMS Education NXT” software by clicking on the appropriate link. 2. On the first menu find “Start a New Program”. Type a name for the program in the box. Choose a name that is easy to remember. 3. Click on the button marked “Go”. 3.

2.

4. Notice now that an orange and white T in the middle of the screen marks the beginning of the program. This is the program window.

6.

5. Look on the left side of the screen. This is called the palette. All of the icons for this program can be found in what is known as the common palette.

4.

6. Look at the Decipher Program One worksheet. Notice that the first icon in the program is the move icon. Find the move icon in the common palette and drag it into the program window to the right of the starting T. 7. Notice that a series of question has appeared in the lower left. 8. Check each of the values included on the stamp, ignoring the others for now.

7.

* *

* *

Port: The “B” and “C” radio buttons should both be marked.

Direction: The upward pointing arrow should be marked to indicate that the robot is going forward.

Speed: Use the slider to set the speed to 75%.

Duration: Use the pull-down menu to change the unit from “rotation” to “seconds”. Then change the value from “1” to “2”.

Gearing Up for Programming and Engineering - p. 111


9. Now to add the wait for time icon, click on the hourglass in the common palette. The wait for time icon is the first in the menu that appears. Click on it and drag it into the program to the right of the move icon.

9.

10. Set the seconds to “1”. 10.

11. Add another move icon to the program after the wait for time icon. 12. Set each of the following attributes:

11.

12.

* *

* *

13.

Port: The “B” and “C” radio buttons should both be marked.

Direction: The downward pointing arrow should be marked to indicate that the robot is going backward.

Speed: Use the slider to set the speed to 75%.

Duration: Use the pull-down menu to change the unit from “rotation” to “seconds”. Check to see that the value is “1”.

13. The program is now ready to download into the robot. Connect the robot with the USB cord, turn it on and click on the download button marked in the image.

Gearing Up for Programming and Engineering - p. 112


A ppendix A

Preparing for the First Lego League

™


Appendix A

Programming & Engineering ™

Preparing for the Tournament The Gearing Up curriculum should give students a solid preparation in engineering and programming. This section includes some advice on using this knowledge to prepare for the First LEGO League (FLL) challenge. Each Fall the First LEGO League reveals a new challenge surrounding a technology-related theme. In the past few years themes have included nanotechnology, climate, power production and transportation. The competition includes both a game and a research project. Students compete in both at the tournament, an event that is usually held in December or January. The game includes a preprinted mat and a series of LEGO models. Students must program robots to start from a base, travel to various locations on the board and to complete tasks before returning to base autonomously. For example, in the 2008 Climate Connections challenge two of the tasks were saving a polar bear and erecting a levy. Each task has a point value and students have 2.5 minutes to complete as many as possible. Students compete multiple competition rounds during the tournament.

Climate Connections Challenge FLL 2008 In this mission, the robot must pull the lever.

The mat shows where to place the Lego models. The robot starts in the base.

The research project asks students to create and present an solution to a problem related to the challenge theme. For instance, in the Climate Connections Challenge students were asked to find a climate-related problem in their neighborhood. Students choose topics like ice on roads, low water levels in lakes and hail damage. At the tournament the students must present their findings to a panel of judges. Awards are traditionally given to teams that score well in the game and research presentation, but students can also win awards for teamwork, programming and engineering based on student responses during interviews.

Breaking into Teams

Completing the Gearing Up activities sets the stage, but the First LEGO League is complex. Usually new teams are surprised by the intensity and level of competition on the day of the tournament. To help them to imagine, it might be a good idea to show one of the videos of a tournament on the Gearing Up CD-ROM before dividing into teams


Appendix A

Programming & Engineering ™

The FLL allows up to ten students to enter the same robot. A large group of students might include several teams. Each team must pay a registration fee, but unless funding is an issue, most coaches advise a team size of four to six students per robot. A major problem remains. The challenge is designed so that it is nearly impossible to finish every aspect. How the students and coach decide to prioritize the work and to divide tasks is not only key to success, but it is also considered a key learning objective. The teams ability to do this is evaluated by the teamwork judge during the tournament.

1 FLL Team

2 Programmers, 2 Engineers, 2 Researchers

But new teams will require more help from coaches to get started. Many coaches encourage their students to specialize. Two students might specialize in programming the robot (programmers) and two in designing parts for the robot (engineers). In a team of six, two students might specialize in research. In a team of four this job may be shared by the whole group. Keep in mind that since all of the students are expected to know about all three, communication is key.

Chassis One early decision involves the chassis. In the Gearing Up curriculum students learn to program using a pre-made chassis. Students learn how the chassis operates as they learn to program. There are three options for a basic robot as the students begin to prepare for the FLL challenge. OPTION 1: Use the chassis from the Constructopedia. This is a good option for beginning students. The chassis is purposely designed to be reliable and stable, although it is also slow and common. OPTION 2: Allow students to modify the chassis from the Constructopedia. This retains the stability of the original chassis, but allows the students some creativity. Modifying the chassis does not take much time, but students will find that it will be difficult to add wheels while retaining the original chassis’s abilities to turn accurately and drive straight. OPTION 3: Help students build a custom chassis. This is a great choice for advanced students. Students obviously learn much from building a chassis, but it is essential that the chassis performs well. Otherwise students will be very frustrated as they try to build and program for individual missions. For that reason, tips for construction and testing follow.


Designing a Custom Chassis ™

1. Step One Find a way to attach two motors together side-by-side. Be sure NOT to attach anything to the orange sections, since these need to be able to spin freely.

2.

Step Two Add wheels, tracks or even feet to the orange portions of the motor. You might want to test several designs. Are large tires better than small tires? Should you use two tires? four tires? six tires?

3.

Step Three Find a way to secure the NXT to your robot. Check your design. Is it stable? Write a program and download it into your robot. Can it turn?

Gearing Up for Programming and Engineering - Appendix A - p.


Appendix A

Programming & Engineering ™

As it is with any large design task, it’s easier to break the task of designing a basic chassis into smaller parts. Refer students to the three steps on the Constructopedia page, “Designing A Custom Chassis”. Before students begin building, it is a good idea to inform them that their creations will be drop tested for stability and run through an obstacle course to evaluate maneuverability. Teachers may choose to use these tests to “qualify” designs for the challenge or to help students choose between alternate designs. Ideally students should work in groups of two or three (if supplies are available). Begin by handing each group two motors. The first step is to find a way to attach the motors together without interfering with the orange portion of each. These need to spin freely for the robot to operate correctly. Check the students’ work and then Stability Techniques instruct them to add wheels, tracks or feet. Again check their work and ask them to complete the most difficult step, attaching an NXT. The process of making an effective custom chassis takes even experienced students 3-4 hours. It works well to divide this into two sessions. In the first, the theme is stability. At the end, the teacher can test all of the partially complete models by dropping them one meter into a box of packing materials (to ensure that no electronic parts are broken). Robots that survive the fall with no damage pass the stability test. The theme of the second building session is maneuverability. Before the session teachers should construct an obstacle course for the robot. Begin by creating a maze on the robotics table with electrical tape, 2” x 4” piece of wood cut into small pieces or LEGO models. After this is complete, it’s easy to add minor obstacles like a field of bricks or a small platform. Students could program their robots to traverse the course after completing their custom chassis, but one fun way to test robots is with a remote control. This can be created with a spare NXT using the directions on the CD-ROM.

Horizontal Nailing Technique

Vertical Nailing Technique

Making Corners with Liftarms

Team Practices

After students divide into teams and select a basic robot, they are ready to begin building and programming for individual missions. Usually there are at least ten missions of varying difficulty (see next page), so it is helpful to begin by doing some initial planning. Consider the following: • • • •

Which missions are the easiest and which are most difficult Which missions can be completed with similar programs or subassemblies Which missions should be grouped together in one program What additional knowledge and skills students will need to complete these missions.

If time permits, students can assist in this planning after an introduction to the complete challenge.


Programming & Engineering ™

Appendix A

Missions from the Climate Connection Challenge Bury carbon dioxide

5 points each

Construct levees

5 points each touching red 4 points each touching green

Test levees

15 points

Raise the flood barrier

15 points

Elevate the house Turn off the lights Open a window

25 points 20 points 25 points

Get people together (Three or more: Red/white people to pink grid Blue/gray people to city/mountain Black/white to research area)

10 points each group

Find agreement

40 points (both teams)

Fund research/corrective action (Money to research area or underground reservoir)

15 points

Deliver an ice core drilling machine

20 points 10 point bonus for vertical assembly

Extract an ice core sample Return sample to base

20 points 10 points

Deliver an ice buoy

25 points

Insulate a house Ride a bike Telecommute and research (computer) Deliver polar bear upright Deliver “sleeping” polar bear Deliver snowmobile

10 points (total, not each) 10 points 10 points 15 points 10 points 10 points


Appendix A

Programming & Engineering ™

It’s also helpful to create procedures for each practice. These might include: •

Team Summit: Practice might begin with a conference around the competition table to review what the team has accomplished and what remains to be done. Many coaches create posters to track this progress and how much time remains. This is also a good time to identify a focus for the practice. At first this might be specific missions, but later it might be a more generic theme such as stability or time management.

The New Idea: When possible, it is a good idea to create or identify an activity that will teach or remind students of a skill they will need to complete the missions or tasks required by the focus. For instance, if a mission requires a strong subassembly, this activity might review nailing techniques. If it might help to use a touch sensor in a mission, students might be asked to create a program that utilizes the touch sensor before starting to program for the challenge.

Goal Setting: This is an excellent opportunity to teach students how to create specific, realistic goals. Part of practice may includes asking students to record a team goal in a notebook or on the dry erase board. For some teams it might be necessary to further divide the goal into jobs for each team member.

Design, Test and Refine: Much of the time in practice is used writing programs, building subassemblies and conducting tests. The other procedures exist to ensure that this time is spent productively.

Scrimmages: As the competition nears, it may be useful to end the competition with scrimmages. These may be as simple as asking students to run the program for the focus mission or as involved as running the students through an actual performance round. For the later, use a stopwatch to time 2.5 minutes and be sure to follow all of the FLL rules. These are available at www.firstlegoleague.org.

Clean-up: Finally, perhaps the most important procedure in terms of retaining teacher sanity is clean-up. One way to do this is to create a job board that lists jobs according to team. Jobs might include cleaning LEGO elements from the floor, cleaning LEGO elements from tables, sorting LEGO elements, checking to see that previously sorted LEGO elements remain sorted and checking to see that computers are properly shutdown.

Research

If building and programming weren’t enough to keep the team busy, teams also need to prepare for the research presentation. These vary from year to year, but plan to prepare the following: •

Background Knowledge: Students will need to know enough about the challenge theme to be able to choose an appropriate topic. It can be extremely helpful to plan a field trip or another experience that will excite and educate the students about the topic.

Research to Identify the Problem: Usually students are asked to research a problem related to the topic which could be solved with good engineering. It’s helpful to spend some time researching and brainstorming before selecting a problem to solve.

Solving the Problem: Students combine their research with their own creative ideas to create


Programming & Engineering ™

Appendix A

Research Project: Climate Connections verbatim from www.firstlegoleague.org

Weather is the condition of the atmosphere measured in short lengths of time (hours and days). Climate, however, is the average weather over decades and centuries in a specific location. We can look out our window and see how weather changes every day, but we need data that has been tracked over hundreds of years to understand how the climate may be changing. Climate tracking is important to communities around the world because the information is used to plan, predict, and make decisions on activities like planting crops or hunting and fishing. People also use data to anticipate the impacts of climate on the economy, food and water availability, tourism, disease control, and many environmental issues. Why is climate important to us? By gaining a greater understanding of the Earth’s complex climate systems, we will be able to work together now and in the future to develop the innovative solutions that will benefit us all and continue to improve the world in which we live. Can FLL teams make the necessary Climate Connections? 1. Research how climate affects your own community. Identify a problem caused by climate in your area, analyze climate data about the problem, and discover what your community is doing about it. Find another community somewhere in the world with the same issue and identify any solutions they are working on. Discuss the various ways climate impacts your community and your lives. Look at climate data available for your area as it relates to your climate problem. Consider talking with experts who work in a climate-related profession every day, such as climatologists, farmers, foresters, and community leaders. Then find another community in a different geographical area that is experiencing a similar problem. Consult the FLL Topic Guide for additional project resources. 2. Create an innovative solution based on the information you gathered. See if others, on a local or even global level, could use your innovation to solve this climate related problem or improve on an existing solution. Consider all the potential solutions to your problem and how great an impact you can have. Talk with experts to see what ideas are already being developed or used. Build your climate connections by creating an innovative solution for your chosen climate problem that could be applied in both communities and adopted by even more communities who face a similar issue. 3. Share your research and solution. Once you have researched and developed your idea, get out there and share it! Take what you have learned to build awareness of the problem and promote your solution, highlighting your research. Use this project to see just how great an impact you can have on your community and your world!


Appendix A

Programming & Engineering ™

a solution to the problem. At this point it might be useful to create drawings or models. Students might also want to discuss their ideas with others, especially experts in the field. •

Consider the Format: On the day of the competition, students will have five minutes to present their ideas to the judges. The presentation is most often a skit, but Power Point presentations, songs and movies can also be good options. It is important to choose a topic that will involve all students and keep the set-up, which is part of the five-minute time limit, simple.

Create the Presentation: The format of the presentation will drive how the group prepares. Teams may need to create scripts, props, Power Points or video footage. Be sure to instruct the students to create a list of sources to provide the judges.

Rehearse and Share: Obviously a well-rehearsed presentation is desirable, but it is also important to share the presentation with others as this is considered in the teams’ final score. Most teams share their presentations with school staff or other students, but teams that find ways to share their presentations with the community and experts earn high marks from the judges.

Prepare for the Tournament: Be sure to pack any props or other essential items for the tournament. Also keep in mind that the judges expect students to set up their own presentations, so be sure to allow the students to practice, especially if AV equipment is required.

At the Tournament: As students enter the room, the judges will set a timer for five minutes. During this time the students should set up and perform their presentation. Afterwards, the judges will interview the students. One judge is evaluating the research presentation and will ask questions related to that rubric. The other judge is evaluating teamwork and will ask more general questions about how the team researched and prepared the robot. Both rubrics are on the CD-ROM.

Interviews The questions after the research presentation are one of two interviews during the tournament. The other is conducted by technical judges tasked with evaluating the team’s programming and engineering. On the day of the tournament teams will use their computers and robots to demonstrate their work while answering questions. Because so much of the tournament involves interviews, it is a good idea to provide opportunities for the team to practice. The goal is to provide confidence rather than rehearsed answers. Possible questions might include:


Programming & Engineering ™

• • • • • • • • • • • •

Appendix A

How does the robot work? What does this attachment do? Why did you design this attachment like this? Was this the first design you had for this piece? How did you start the work on your robot? What sensors do you use on your robot? Could each member of the team describe how he/she contributed to the robot? How did your group divide the work? What would you do differently if you did this over again? Did you have any major problems with the robot? How did you solve the problem? What part of the robot is the best? What did you learn from this experience?

Before the Tournament Once the team is prepared for the tournament, it’s time to pack. Here is a possible checklist: Team robots loaded with programs All subassemblies with carrying case Computers with team programs (Make sure that these work outside of the school building.) Team programs backed up on a flash drive USB cords AC adapters and/or back-up batteries Items to entertain the team during down time Copies of schedule, paperwork Props, scripts or AV equipment needed for the presentation

10


A ppendix B Robotics in the Classroom

™


Programming & Engineering ™

Appendix B

Robotics in the Classroom Gearing Up for Robotics works very well in a classroom setting. It can be a great start to a very rewarding course. But at times a robotics classroom can look and feel different than other classrooms. Robotics is supplyintensive. It requires constant movement around the room. At any given time some students are excited and challenged while others are frustrated and in need of help. There are often more students per adult during the school day than there are after school. And, during the school day assessment becomes more important. There aren’t easy solutions to these problems, but over several years of trial and error, I’ve found multiple strategies that help. This section outlines my recommendations.

Supplies Team Names: The first step to organizing the many supplies

involved with robotics is to create team names. I allow students to create the names that they will use during competitions, but I also use static team names that remain constant from class to class and year to year when organizing supplies. The names on the right are several from a set that were inspired by famous robots. These, and a set featuring LEGO element names, can be found on the CD-ROM. These can be used to identify each teams’: •

Work Space: A table or several desks pushed together should provide enough space for teams to program and build in the same area.

Asimo Dante Robonaut Jason Opportunity

Storage Area: Designating a shelf, locker or shoebox-sized container for each group prevents many issues.

Computer: It’s wise to label computers, especially if the students will be saving files directly to the hard drive.

Chassis/NXT: Labelling each NXT or chassis helps to hold students team names are available on the CD-ROM. accountable.

Folder: In many challenges and activities I require teams to keep documents that outline their strategy, their goals or their use of time.

Canadarm Signs and labels featuring these

Sorting: A common debate amongst robotics teachers is how to best organize the LEGO elements that

remain once chassis are built. After much experimentation, I recommend a sorting system where each element has it’s own designated location. Elements with the exact same shape go in the same bin even if they are different colors. That means that every LEGO collection has an area where all of the elements are sorted. There are also empty sorting trays and empty bins for unsorted LEGO elements.


Appendix B

Programming & Engineering ™

These elements SHOULD go in the same bin since they are the same shape.

These elements SHOULD NOT go in the same bin since they are different shapes.

These elements SHOULD NOT go in the same bin since they are different shapes.

As students build or clean-up they put unsorted LEGO elements into the designated unsorted bins. This keeps hasty students from putting LEGO elements into the wrong place.

Students put stray elements into the unsorted bin.

Early in the Gearing Up Curriculum I plan a short lesson concerning sorting. I use the images in the sorting power point (on the CDROM) to explain how shape matters when sorting, but color does not. Then students work with a partner to fill each compartment in an empty sorting tray with five elements that have the same shape. Once each compartment has at least five elements, the team is done. This method gives sorting an end, which is important. Students can race to finish or there can be a requirement that each team sorts one tray before they can begin working. Students also do the hard work, so they are more likely to keep the collection sorted.

At set times each team sorts from the unsorted bin into sorting trays.

After the sorting activity the LEGO elements in the sorting trays still need to be placed into the correct containers in the sorted bins. I choose to do this job myself as a way to ensure quality control, but some teachers delegate this to a trusted student.

Management Completing a robotics challenge requires students to constantly move around the room, but this can become very difficult to manage if students are off-task. Team size and composition are key to keeping all students engaged. While I have successfully managed teams of four in the past, I now have students work in pairs whenever possible. In each pair one student is responsible for engineering and one is responsible for programming. This arrangement keeps all students busy and helps me to keep students accountable.

The teacher places the elements from the sorting trays into the sorted bins.

I also group students based on student input and common sense, rotating these teams often. I have the option to rotate teams often because I tend to do more short challenges in class rather than one large FIRST LEGO League


Programming & Engineering ™

Robotics Lab

Driver’s License

Appendix B

challenge. Each of these challenges includes tasks of varying difficulty. This ensures that both the gifted and struggling robotics student are challenged. When I do use larger challenges, I break these into parts so that the tasks for each lesson are still manageable. With some classes these modifications are enough to keep the majority of students engaged during periods of movement. Other classes seem to need more specific rules and procedures.

When I shared a class with a teacher that was uncomfortable with this movement, he created and enforced the rule “Talk to your team, but not to other teams” to limit off-task discussion. We also used “Robotics Driver’s Licenses” that were laminated and hung from lanyards. Each table would be given a limited number of licenses at the beginning of class. Students had to have a licence to leave the table, and one particular student, the “traffic officer”, was tasked with reminding students to wear the licenses. Licenses could be revoked as a consequence of off-task behavior.

Rules for Computer Use: One thing that I don’t want to worry about during class is the misuse

of computers, so before touching a computer in class, students must pass a simple quiz concerning the computer rules. 1. Each day two students will be chosen to be the “IT” department. They will distribute computers. Leave your laptop on the desk unless you are one of these students. 2. Only open applications that are part of the lesson. That means that on most days the LEGO MINDSTORMS software will be open, but internet browsers will not. 3. Use common sense. For example, do not run, eat or drink in class when computers are out. 4. Students who do not follow these rules do not touch the computer for one day. Do not expect a warning. I follow these rules consistently, so computer problems are kept to a minimum. But I also plan alternate activities for students who break these rules.

Providing Assistance: One problem that I don’t mind is that eager students are constantly asking

for help during class. On busy days I verbally give students a number when they say my name and keep a running mental list of students who need help. To keep the list from getting too long I try to have written instructions related to each lesson. I also commonly enlist students to teach other students. Sometimes this is built into the rubric. For instance, earning an A+ in a challenge with the light sensor might require helping another student compute the threshold. If possible, it also useful to solicit the help of older students or adults to assist on a regular basis.

Clean-up: For many clean-up is the most frustrating part of a robotics class. For that reason I tend

to spend time deliberately teaching each clean-up job. Once students master one job, we move to the next. This works well with the Gearing Up curriculum since all of the clean-up jobs aren’t necessary immediately. Once students begin working on a challenge, these jobs are assigned to teams on a clean-up board. I use hanging signs so the jobs can be rotated every day.


Appendix B

Programming & Engineering ™

Floors: This group usually needs the most encouragement to continue working until nearly all of the LEGO elements on the floor have been moved to an unsorted bin. Bins: Some teams have the job of checking to see that none of the LEGO elements in the sorted bins are in the wrong place. In my classroom the sorted bins are numbered, so teams are usually assigned specific bins to check. Challenge: This team retrieves lost challenge elements and removes stray LEGO elements from the robotics table.

Charge: In some classrooms it is difficult to charge all of the robots each night, so sometimes I set up a charging station. The team with this job plugs in their robot before they leave.

Computers: This team could be in charge of making sure that computers are shut down and/or retrieving and wrapping the USB cables.

Every team is also responsible for saving their programs, storing their robots and cleaning their table. But, if I need an additional cleaning job I sometimes assign a team “Tables”. That team’s job is to remind other teams to complete these tasks.

Asimo

Floors

Dante

Bins 1-7

Robonaut

Bins 8-14

Jason

Challenge

Opportunity

Charge

Canadarm

Computers

This is an example of a clean-up board. In this classroom there are two pairs of students in each team.

I also have some tricks for keeping students motivated to clean-up well. One is to create a rating system to rank job completion. I check and score each job after class and then post the results the next day. Another way to quantify the success of clean-up is to use a clear tube. Each LEGO element that is left out or that is found in the Sample Rubric: wrong bin is added to the tube. Then these measures can be used as part of a contest or can be linked to rewards or consequences. For a C: Assessment Drive the robot from the base to a basket. Formative Assessment: No one wants to spend a week For a B: working on a robotics challenge to find that most of the teams Make a basket. cannot complete it in the end. To avoid this problem I tend to build For an A: a lot of formative assessment into each challenge. Make a basket using a One way to do this is to provide a very simple rubric with sensor. milestones that each team needs to complete to reach a specific For an A+: grade. Students are instructed to check in after reaching each Help another team to use milestone and I keep track of these on a checklist. I use the a sensor. checklist to guide my efforts in the classroom and when we are out


of time, I use the scores as part of the grade for that challenge.

#1 Investigate

Another key piece of formative assessment is a robotics notebook. Like many other middle school classrooms I start the day with daily warm-up questions. These are sometimes content-related and sometimes they are questions about a team’s progress or goals. Circulating around the room while students write provides an imprecise, but valuable, tool to measure understanding.

Summative Assessment: While I

have provided several examples of pencil and paper tests on the CD-ROM, robotics assessment usually involves a series of rubrics.

Hmm . . . Let Me Plan a Solution. Oh No! We Need a way to show how we created our robots!

#2 PLAN

#5 Evaluate Brilliant!

Our Students are going to love this

Rubrics vary challenge to challenge based on the standards and objectives I am trying to address. Some provide group scores and some are individual. So it’s difficult to provide a set of generic rubrics here. But I can say that whenever my goal is to evaluate the quality of a robot, I make a rubric based on these three criteria:

#3 CREATE

Ability: Does the robot work? Does the movement work like the engineers intended?

Stability: Do the parts of the robot stay together? Is the design strong?

Creativity: Did the engineers approach the problem in a unique way?

5,4, HANDS Up! It's time to make a comic about how your team designed your robot.

#4 TEST

The CD-ROM also includes rubrics used by the FIRST LEGO League to address programming and teamwork. I tend to use elements of these to create more student-friendly rubrics for use in class. Often the goal of the robotics class is to involve students in the design cycle. This is a great opportunity for a writing assignment since students have had a rich experience that they want to share, but they usually haven’t spent much time reflecting about how their experience fits into the design cycle. As a change of pace, I’ve also had students record their use of the design cycle in comic strips or iMovie clips.


Name: __________________________ Period: ______

Comic Life

PART ONE: Do Now: Make a list of design problems that you encountered while building your robot. These could be problems with the program, the robot or the parts that you designed. Write your list here:

The Desig

PART TWO: Plan Your Comic: Your mission is to create a comic that describes how your team built your robot. An A project will include examples of each of the following steps of the design process:

Inve

1. A time when your team identified a problem. (Investigate)

Find Rese

Investigate

Identify the Problem Research

__________________________________________

Plan

2. A description of how your team planned a solution to the problem. (Plan) __________________________________________ 3. A description of how you designed a solution to the problem. (Create)

Plan

Evaluate

Brainstorm Choose a Solution

Test Refine

__________________________________________ 4. A description of how you tested your design. (Evaluate)

Create

Build a Prototype

__________________________________________ 5. A description of what you did after you tested. __________________________________________ PART THREE: Create the Comic: You may make a comic alone or you may work with your partner. 1. On the computer, click on the

.

2. Click on “Applications” and then “Comic Life”. 3. Use the camera to capture pictures of you and your robot. 4. Add the images to your comic. 5. Add words to show what the characters are saying and thinking. 6. Add words to show the steps of the design process (Investigate, Plan, Create, Evaluate). 7. Add a title and your names. 8. Save your comic. 9. Print a copy of your comic for a grade.

Brain Choo

Cre Turn

Eva

Test y Decid

Are th


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