WALL-E is 4008A's robot, created for the VEX Tower Takeover game. It consists of a drivetrain, a cascade lift, and a claw. Its main purpose is to grab cubes and stack and place them in the goals and towers, which it does with the cascade lift and claw.
WALL-E
Drivetrain
WALL-E's drivetrain has 4 total omni wheels, with two motors. On each side, the wheels are connectd by gears (a 1:1 ratio) to share power. We decided to limit motors on our chassis in order to give power to the elevator lift. This lift and the claw fit in between the two sides.
Cascade Lift
The elevator cascade lift is an essential part of the robot, and must be able to lift cubes high enough for stacking as well as tower scoring.
The lift is powered by 5 motors and has three stages, each smoothly sliding up as they elevate the cube. These stages are made with linear sliders, chain, and sprockets.
Later on in the season, to improve the efficiency of the lift, we increased spacing between the sliders for each stage, reducing the friction between each stage. We also made the connecting points of the lift stronger, screwing down the lift so that it would not tilt. Thus, the amount of friction between the stages was further reduced.
Claw
WALL-E's claw grabs the cubes and holds them as the robot navigates to a goal or tower.
The claw is programmed to open, close, and hold the cube. Each side of the claw is made of two c-channels that are connected, and that unit attaches to a gear. In addition, the claw is padded with foam and wrapped with anti-slip mat, secured with rubber bands. This helps with the grip of the claw.
The claw is powered by one motor, which attaches to the gears, powering the two sides of the claw.
