VEX Robotics PROGRAM OVERVIEW Building upon RoboAchiever’s many implementations of its Lego Mindstorms’ RCX Robotics platform, we are now pleased to introduce “competition grade” robotics training with a strong VEX Robotics curriculum. VEX competitions are routinely held in Connecticut and throughout the Nation. The company has a full complement of VEX Robotics licenses to for student use in completing online Robot Virtual World training. The Company’s Founder and CEO, Don Bertrand, is a Certified VEX Robotics instructor as awarded upon successful completion of Carnegie Mellon Robotics Academy’s instructor training program.
This program is conducted in 3 parts. The first involves construction of the Clawbot robot, it’s initial setup and operation. The second involves RobotC code learning, primarily through RoboAchiever’s licensed seats for Robot Virtual World’s online instruction. The third provides detailed implementation of all that was previously learned, as students attack the presented robot task challenges.
RoboAchiever Learning Systems 5 Science Park at Yale, New Haven, CT 203 430-3141 www.roboachiever.com
CLAWBOT ROBOT CONSTRUCTION Source: http://curriculum.vexrobotics.com/curriculum/intro-to-autodesk-inventor/building-the-clawbot The following Building Guide provided with Clawbot will be used to guide the Clawbot’s construction, in accordance with the workflow stages presented on the VEX EDR Curriculum website. The curriculum is made freely available for educational purposes. Copyright Š 2002-2015. Curriculum content is made freely and publicly available by VEX Robotics, Inc. solely for educational use and may not be reproduced, modified and redistributed without attribution to VEX Robotics. Curriculum, or any portion thereof, may not be used for monetary gain without the explicit consent of VEX Robotics. VEX and VEX Robotics are trademarks or service marks of Innovation First International, Inc. All Rights Reserved. VEX Robotics, Inc. is a subsidiary of Innovation First International, Inc.
Stage 1: Review the Robot Model The students are provided a live demonstration of a pre-constructed Clawbot. Some student hands-on navigation will be allowed to inspire students to perform the development work that lies ahead. Stage 2: Starting the New Assembly In this stage students learn that the structural frame members have square holes that have to be aligned correctly.
Stage 3: Complete the Base Frame Students will assemble all the parts required for the base frame by adding three more C-channels and a bumper. Stage4: Add Standard Parts to the Assembly Students use standard parts to assemble the frame.
Stage 5: Assemble Bearing Flats and Rivets In this Stage, students add bearing flats and rivets to the base frame. VEX robot drive shafts rotate in bearing flats. These flats are held onto the frame using bearing pop rivets. Stage 6: Assemble the Driveshaft and Collar In this Stage, students add the drive shafts and collars to the base frame assembly. The drive shafts are inserted into the bearing flats. Collars are added to the ends of the shaft to hold the shaft in place.
Stage 7: Assemble a Wheel In this Stage, students add a wheel to the Clawbot. The wheel assembly consists of a 60 tooth gear, spacer, 4-inch wheel and a collar. These parts are placed in the assembly and constrained using various workflows. Constraints are placed between each part to make sure that they rotate correctly.
Stage 8: Create a Wheel Subassembly Students simplify the placement of wheel parts by creating a subassembly. To reduce the time required to create a wheel assembly, the parts are demoted into a subassembly. With the wheels in place, a 60-tooth gear is added between the wheels, and motion constraints are added to the gears.
Stage 9: Align the Gears Students use work planes to align the gear teeth. To correctly align the gear teeth, work planes are created through the center of the teeth or a gap between the teeth. These work planes can be used to align the teeth by constraining the work planes to each other.
Stage 10: Assemble the Claw Arm Drivetrain In this Stage, students build the claw arm drivetrain using gears, shafts, and shaft collars. The claw arm drivetrain is assembled using 84 tooth gears, 12 tooth gears, shafts, and shaft collars. The gears are aligned using work planes like the wheel drivetrain.
Stage 11: Add the Cortex Microcontroller Students assemble the Cortex microcontroller and battery straps onto the base frame. Motors are added to the wheel drivetrain and the motion of the gears and wheels is checked.
Stage 12: Assemble the Claw Arm Students add the claw arm to the Clawbot assembly.
The channel is constrained to the 84-teeth gears.
Stage 13: Complete the Robot Assembly Finally, In this Stage, students add the remaining parts to complete the robot assembly. The claw is constrained to
the claw arm. Braces are added to provide additional support to the vertical channels.
CODING Source: http://learn.cs2n.org/course/view.php?id=106 Our company provides students licensed access to the coding tools and challenge exercises provided in RoboMatter’s Robot Virtual World and VEX Robotics programs. Use of these tools requires coding instructions that we provide under the freely available CS-STEM (CS2N) online platform. We again here state the provider’s terms in full. Welcome to the Computer Science Student Network’s CS2NLearn, a self-paced Learning Management system (LMS). At CS2NLearn you will find free access to Robotics Academy training materials, but you will need to register at cs2n.org
Section 1: Introduction to Programming Watch the following videos (found on the CS2N.org website): Fundamentals - Introduction to Programming: • Programmer and Machine • Planning and Behaviors • ROBOTC Rules Part 1 • ROBOTC Rules Part 2 Refer to the Building Behaviors, Pseudocode, Establish a VEXnet, and Flowchart Handouts Section 2: Getting Started with ROBOTC Follow along with the following videos and documents to get your physical VEX Cortex programming environment configured: • Link between the Cortex and Joystick Section 3: Moving Forward Watch the following videos (found on the CS2N.org website): Movement - Moving Forward: • Moving Forward Program Dissection • Reversing Motor Polarity • Renaming Motors • Timing Complete the following challenge in the RVW Curriculum Companion: • Sumo Bot Challenge Section 4: Speed and Direction Watch the following videos (found on the CS2N.org website): Movement - Speed & Direction: • Motor Power Levels • Turning and Reversing • Manual Straightening Before you solve the Sentry Simulation Challenge write your code in psuedocode and flowchart format. Use the psuedocode and flowchart handouts in Lesson 1 Introduction to Programming as a guide to develop the psuedocode and flowchart.
Complete the following challenge in the RVW Curriculum Companion: • Sentry Simulation Level 1 Section 5: Shaft Encoders Watch the following videos (found on the CS2N.org website): Movement - Shaft Encoders: • Shaft Encoders • Forward for Distance Part 1 • Forward for Distance Part 2 • The Sensor Debug Window • Forward and Turning ROBOTC Webinar: • Moving Forward with Shaft Encoders Before you solve the Basketball Drills Challenge write your code in psuedocode and flowchart format. Use the psuedocode and flowchart handouts in Lesson 1 Introduction to Programming as a guide to develop the psuedocode and flowchart. Complete the following challenge in the RVW Curriculum Companion: • Basketball Drills Challenge Section 6: Automated Straightening Watch the following videos (found on the CS2N.org website): Movement - Automated Straightening: • Automated Straightening Part 1 • Automated Straightening Part 2 • Values and Variables Part 1 • Values and Variables Part 2 ROBOTC Webinar: • Moving Straight Forward with Shaft Encoders Complete the following challenge in the RVW Curriculum Companion: • Labyrinth Challenge Complete the quiz before you move to the next lesson. Automated Straightening Practice Quiz Section 7: Joystick Mapping Watch the following videos (found on the CS2N.org website): Remote Control - Joystick mapping • Introduction to Remote Control • Real-Time Control • Mapping Values Part 1 • Mapping Values Part 2 Section 8: Timers Watch the following videos (found on the CS2N.org website): Remote Control - Timers • Time and Timers • Using Timers Section 9: Buttons Watch the following videos (found on the CS2N.org website): Remote Control - Buttons • Remote Control Buttons
• Remote Start • Controlling the Arm Part 1 • Controlling the Arm Part 2 • Controlling the Arm Part 3 If you haven't already, download and install the latest VEX Competition Virtual World. Complete the challenges using your real VEX robot and VEXnet Joysticks. Section 10: Limiting the Arm Watch the following videos (found on the CS2N.org website): Sensing - Limiting the Arm • Configuring Sensors • Limiting the Arm Part 1 • Limiting the Arm Part 2 Complete the following challenges using your real VEX robot and VEXnet Joysticks: • Quick Tap • Minefield Removal Challenge (Again)
Section 11: Behaviors and Functions Watch the following videos in the VEX Cortex Video Trainer: Sensing - Behaviors and Functions: • Behaviors and Functions Part 1 • Behaviors and Functions Part 2 • Passing Parameters Part 1 • Passing Parameters Part 2 Complete the following challenge in the RVW Curriculum Companion: • Incorporating Functions Section 12: Forward until Near Watch the following videos (found on the CS2N.org website): Sensing - Forward until Near: • The Ultrasonic Rangefinder • Forward until Near • Straight until Near • Straight until Near (Fine Tuning) Complete the following challenge in the RVW Curriculum Companion: • Speed of Sound Challenge Section 13: Line Tracking Watch the following videos (found on the CS2N.org website): Sensing - Line Tracking: • The Line Tracking Sensors • Calculating Thresholds (Follow along on the Utility > Line Tracking Table in the RVW Curriculum Companion) • Basic Line Tracking • Line Tracking for Distance • Optimized Line Tracking Complete the following challenges in the RVW Curriculum Companion: • Robo Slalom Level 3 • Minefield Traversal Section 14: Gyroscope
Review the following materials from ROBOTC.net: • Gyroscopes Webinar • Gyroscopes Overview Complete the following challenge using your real VEX robot and VEXnet Joysticks: • Robo 500 (Use the Gyroscope instead of the Light Sensor)
PERFORMANCE CHALLENGES Source: http://curriculum.vexrobotics.com/curriculum/the-game Upon completion of their online code learning in Robot Virtual Worlds, students transfer such learned coding to command the physical robot. Various game-mat challenges will be provided, including the following challenge that appears on the VEX EDR Curriculum website. The Can Cleanup Challenge The following challenge gives students the opportunity to test their robot and use the full range of its functionality. To perform this challenge you will need the following: • A completed VEX Clawbot • 14 empty cans (or similarly sized blocks or plastic bottles) • A container to act as a goal • Approximately 12’x12’ of open space To perform this challenge you will need to complete the following steps. • In the center of your open space, create a large pyramid using 14 cans OR blocks. Make a square base of 9 cans/blocks. On top of this base, place a second level of 4 cans/blocks, approximately centered on the base of 9 cans/blocks. On top of the second level, place a single can/block, approximately centered. • Place the empty container approximately 8’ away from the cans/blocks. • Place the Clawbot next to the empty container. • Using the VEXnet Joystick to control the robot, try to place as many cans as possible into the goal in a period of two minutes. • Repeat the challenge to see if it is possible to increase the number scored. • If there are multiple robots in the class, try playing this challenge as a head to head game. Add a second goal, and have the two robots race to see which is able to score the most cans in a two minute time period.
ROBOTC
Setup
Establishing a VEXnet Link Setup Guide In this document, you will learn how to pair a VEX Cortex Microcontroller to a VEXnet Remote Control, allowing them to communicate over VEXnet. This document assumes that you have already updated the master firmware on the VEX Cortex and VEXnet Remote Control. VEXnet is an 802.11 WiFi communication system between the VEX Cortex and VEXnet Remote Control. VEXnet features include: • Easy to connect (No IP addresses, MAC addresses, passwords, or special security modes) • Multiple layers of security built-in and always on • No wireless access point needed; each VEXnet pair makes its own private network • Hundreds of robots can operate at once; every VEXnet robot has a hidden unique ID • Optional tether for wired communication • Optional 9V battery backup to maintain wireless link during a main 7.2V power loss • LED scheme displays the status of the Robot, VEXnet link, and Game (Competition Mode)
1. Begin by connecting both the Cortex and VEXnet Remote Control to charged batteries.
1a. Connect a Battery to the Cortex Connect a 7.2V robot battery to the Cortex, but do not power it ON.
1b. Install Batteries in the VEXnet Remote Control Remove the battery cover plate on the remote control. Install 6 AAA batteries, and replace the battery cover plate. Do not power the remote control ON.
© Carnegie Mellon Robotics Academy / For use with VEX® Robotics Systems
VEXnet Setup Guide • 1
ROBOTC
Setup
Establishing a VEXnet Link Setup Guide
(cont.)
2. Tether the USB port on the VEXnet Remote Control to the USB port on the Cortex using a USB A-to-A cable.
2a. VEXnet Remote Control USB Port Plug one end of the USB A-to-A cable into the USB port on the VEXnet Remote Control.
2b. VEX Cortex USB Port Plug the other end of the USB A-to-A cable into the USB port on the VEX Cortex.
3. Power the Cortex ON. After a few seconds, ROBOT and VEXnet LEDs will blink green, indicating that the Cortex and VEXnet Remote Control have successfully paired. 3a. Turn the Cortex ON
3b. Status LEDs The ROBOT and VEXnet LEDs will blink green once the Cortex and VEXnet Remote Control have successfully paired.
© Carnegie Mellon Robotics Academy / For use with VEX® Robotics Systems
VEXnet Setup Guide • 2
ROBOTC
Setup
Establishing a VEXnet Link Setup Guide
(cont.)
4. Turn the Cortex OFF.
5. Remove the USB A-to-A cable from the VEXnet Remote Control and Cortex.
6. Insert VEXnet USB Keys into both the VEXnet Remote Control and Cortex.
6. VEXnet USB Keys Insert VEXnet USB Keys into the VEXnet Remote Control and Cortex.
Note: It does not matter which VEXnet USB Key you insert into the Cortex versus the VEXnet Remote Control. Pairing the Cortex and VEXnet Remote Control establishes the link; the VEXnet USB Keys act as antennas for the link.
© Carnegie Mellon Robotics Academy / For use with VEX® Robotics Systems
VEXnet Setup Guide • 3
ROBOTC
Setup
Establishing a VEXnet Link Setup Guide
(cont.)
7. Power the Cortex and Remote Control ON. After roughly 15 seconds, the ROBOT and VEXnet LED’s will blink green, indicating that the VEXnet communication link has been established.
7a. Turn the Cortex ON
7b. Turn the VEXnet Remote Control ON
7c. Status LEDs After roughly 10 seconds, the ROBOT and VEXnet status LEDs will start blinking green. With the VEXnet link established, you should power OFF your Cortex and VEXnet Remote Control to preserve battery.
© Carnegie Mellon Robotics Academy / For use with VEX® Robotics Systems
VEXnet Setup Guide • 4
ROBOTC
Setup
Establishing a VEXnet Link Setup Guide
(cont.)
Troubleshooting Issue: Slow blinking green ROBOT light on the Cortex Solution: Download the Cortex Master Firmware using ROBOTC. Issue: Slow blinking ROBOT green light on the VEXnet Remote Control Solution: Push and hold CONFIG button for about 5 seconds, until the status
LEDs starts blinking green. Release it, wait for another 5 seconds, and then turn the VEXnet Remote Control OFF and then back ON. If that fails, download the VEXnet Joystick Firmware using ROBOTC. Issue: Yellow or red ROBOT light on the Cortex Solution: Make sure you are using fully charged Robot battery. Issue: Yellow or red ROBOT light on the VEXnet Remote Control, even though
they are both green on the Cortex. Solution: Power cycle both the VEXnet Remote Control and CORTEX.
© Carnegie Mellon Robotics Academy / For use with VEX® Robotics Systems
VEXnet Setup Guide • 5