FIRST | Recycle Rush
GRT 2014-2015
Recycle Rush is played on a standard carpeted 27 ft by 54 ft field. The field is divided into two zones, one for red and one for blue. The main purpose of the game is to stack totes on top of white, slightly elevated strips. 2 points are awarded per tote on the strip, and stacking a recycling bin on a stack multiplies each totes value by 3. Totes can be collected by either the landfill, a group of totes near the middle of the field; or the human player stations near the drivers. During qualification matches, teams can place four yellow totes on the middle barrier to earn 20 points, with an additional 20 points awarded if the totes are stacked. Teams are also allowed to throw litter into the opposing alliances side to gain 4 points per noodle.
Our robot: Brontosaurus Rex
For Recycle Rush, GRT built Brontosaurus Rex, a robot weighing 120 pounds with a dedicated bin grabber that is optimized to quickly make a 4-stack and put a bin on top. A large, flat chassis allows the robot to steadily, yet quickly navigate the field without fear of toppling our stacks over. The tote lifter has self-adjusting fingers that conform to the tote's contour in order to quickly grab the tote with minimal driver intervention.
Tote stacker
Inspired by the design of a forklift, our elevator slides over a pair of 2x1 box beam with precision-placed ball bearings to prevent binding and bending. The whole system is powered by a custom-made, 2-CIM gearbox with a chain drive. At the end of the modular elevator box is a number of aluminum fingers that reach under tote's ridge to securely and quickly lift the container. Each finger is held up by a rubber band that allows for conformity to the tote's underside while still collectively able to lift up to 3 totes at once.
Drivetrain
Despite designing improvements to our previous year's two-speed gearbox, our drivetrain team decided that a single-speed gearbox would provide the necessary stability and reliability that moving stacks of totes requires. Combined with our traditional belt-in-tube west-coast drive, it allowed for an extremely smooth and steady drive that took up a minimal amount of space on the chassis.
Bin grabber
Arguably more important than our tote stacker, our dedicated bin grabber can easily grab bins from the middle barrier and hold it upright even when moving around and performing other actions. Combined with our autonomous, it allowed our team to make a 24-point stack within the first 30 seconds of teleop. The simple and effective triangle on the end is kept upright no matter what angle the arm is at thanks to a clever linkage system.