The Modified Claw Jessie Headrick EunHyeok Jang
Table of Contents
1. Strategy ----------------------------------- 2 2. Idea #1 ------------------------------------ 3 3. Idea #2 ------------------------------------ 3 4. Lifts ----------------------------------------- 5 5. Idea #3 ------------------------------------ 8 6. Idea #4 ------------------------------------ 10 7. Implementation of Modified Claw -- 11 8. Pros and Cons -------------------------- 17 9. Solutions ---------------------------------- 19
Strategy Strategy
Skills
Time Game Parts Points
High Hanging Bar with Ball - hook on side of claw - elevator Lift
3
Agile Manuverablility - slide to side - quick turns - over bump barrier
2
?
Bucky Ball into Goal - claw bucket
2
5-25
10-20
20
Skills: Does our team have the capability to implement features needed for this
strategy.(1-3) 3 = most capable Time/Parts: Availability of parts and time resources (1-3) 3 = Sufficient resources
First Idea
Alternative Idea - FAILED
Advantages of the Design
- It would be much faster to deposit the balls into the chute - Also the big claw at teh top could grab the large balls and bring them to the goal zone
Disdvantages of the Design
- It cannot fit under the barrier bar - The large calw would be unstable - Moving the balls against gravity may prove problematic - Making the chute would be difficult - It would be “front heavy�
Elevator Lift:
Lifts Scissor Lift: At first I thought this would be the best way to conserve space and quickly elevate my robot but it proves to be more problematice then helpful for us. Forums said the following:
Advantages of Scissor Lift - Fits under barrier efficiently
The elevator lift was my second choice for a lift because of its stability and strength. It utilizes gears and gear tracks for construction. For a multistage elevator lift a moving chain is used to extend it.
Disdvantages of Scissor Lift
- Heavy and unstable when extended - Side loads are problematic - Less stability as he height increases
Unstable if heavy up top
Must be built with percision. Very difficult to construct. Online forums did not advise this for the classroom.
! Must make the base heavy
Disdvantages of Multistage Elevator Lift
- If the chain is jammed in any way during the fight it will be rendered useless -The further the stages go the more unstabe it becomes
Idea Change
This is the extended multistage lift. As you can see, there is no chain attached in this diagram becasue I have yet to find learn how to add a chain in autodesk inventor. Regardless, the function and movement of the multistage elevator is ibvious through the image. The biggest problem with is design, in my opinion is the chain. Stringing the chain around this lift could prove very problematic.
Advantages
- Less Metal and no chain - More simple dependable design
Disdvantages
- Long arm may be unstable - The chute at the end of the arm will be difficult to raise
Motion Stages and Measurements 1.
This would be the robot in standard position. It will scoop up the ball while the arm lowers the arm.
2.
The large gear raises the arm up and the elevator shaft moves the secondary arm up to reach the goal chute.
3.
The chute with the balls is lowered down to the mouth of hte chute and dumps the bucky balls.
Modified Claw The chute idea turned out to be too unstabel and not necessarily feasable for this elevator design. So we decided to go back to the basics with a modified claw. As you can see to the left the claw is composed of the original claw base, two metal pinchers with pexi glass attachments to hold the ball, and rubber ends to pinch large balls.
Autodesk Inventor Images of the Modified Claw
The Claw
TOP:
giant modified claw elevator arm
base of clawbot claw
arm
side-to-side wheel omnidirectional wheel
Indivisual Images: Parts LIFT:
elevator arm
SIDE:
Elevator Lift:
In this image you can see up close the components of a basic elevator shaft. There must be gear track, metal holder, small gear, and a motor. The gear track is attacked to a 17.5“ rail that gives the robot height to reach the hanging bar.
untwisted pincher extended wheel rail
Extended Wheels:
Close up of the exteneded wheel: It is composed of three 40 tooth gears and two 6 tooth gears. We hope to provide stability as well as manueverability.
CLAW:
The Claw:
This image shows the claw becore the two “pincher“ rails have been twisted into position to accompany the plexi glass. The base of this claw is simply the original claw. it is composed of one motor four gears, and two inner springs that retain tension within the claw.
Pros and Cons of The Design
Pros and Cons of The Design Advantages
Disdvantages
- The arm extends long enough with the elevator shaft t reach the high hanging bar, as well as the bucky bal chute
- The modified claw is quite heavy and can only be raised slowly
-I have omnidirectional wheel that will allow me to move in all directions accept for diagonally -Smooth movements, simple design
-The base of the robot is a bit unsturdy because it is top heavy when the arm is raised - The side-to-side wheel needs modification - May be using too many motor
Solutions 1. Claw is too heavy - More the fulcrum of the arm to relieve the tension and weight of one end
4. Side-to-Side Wheel - Change the wheel to create more friction - Change the gear construction to “snap“ into place - Mini elevator lift for the preconstructed wheel assembly
- Add another motor to the arm. (This is a less desireable fix because, in a way it is the less elegent solution) X : Too many motors on the robot = heavy - Add rubber bands X : Even using many, the effect is not very strong 2. Chassie Rail Support - Add supports similar to the claw bot X : Space consuming - Add a metal sheet between the rails X : Doesn’t necessicarily support the rails
3. Base Weightiness - Use the battery to weigh down a certain parts of the wheel base that are unsturdy - Extend the Wheel base X : Ssacrifice of manuverability - Add metal/weighty material to the base of the robot X : Not an elegent fix, Just creates a chunkier robot.
5. Bump - Change currect supports to curled rail. This will support and elevate the robot over the bump rather than prove an obsticle.
End