Team 3940 is so excited to present our robot for this season: Rattlesnake
https://youtu.be/lbJbatCbwck
- AndyMark AM14U5 drive base in an 8WD configuration with AndyMark Performance Wheels
- Multi-position intake for pickup of cube from the floor and cone from the floor and substations
- Intake handoff to pneumatic actuated gripper
- Two-jointed arm with position control that passes through the robot from intake to scoring position
- RGB LED indicators for human player communication and robot status
Thanks to all of our sponsors and we will see you at the FIN Mishawaka & Greenwood events… and hopefully more!
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This is what we’ve come to expect out of Cybertooth - slick, relatively simple (for this year’s game) robots that make everyone else go “Why didn’t we build that?”
The floor intake is the part that’s really making me jealous 
. Can you show more of how it’s actuated and how the outer part folds in when retracted?
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Should’ve been called wormie. Cool bot. Hope we get to play together at Penn.
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The intake has two pneumatic cylinders, one on each side of the intake, each with only the return side plumbed. In most scenarios, the intake is “loose”, meaning those cylinders can freely extend and retract without resistance. The whole intake pivots around the axis the wheels are driven from via a set of #25 chains and sprockets fastened to the intake plates.
When extending the intake, the cylinders retract to keep the rotating bit from hitting the bumpers. If we intend to pick up a cone, the cylinders remain retracted to keep the intake rigid and at the angle we think is best for picking up cones. If we intend to pick up a cube, once the intake is past the point where anything would impede it, the cylinders vent and the intake goes back to being loose. It’s this “cube intake” position that gave us our name for the season - it looks suspiciously like a rattlesnake tail when its slightly bobbing back and forth as we approach a cube.
When the intake retracts, in all states it immediately goes to the “loose” cylinder position and just rotates back to its stowed position. The weight of the two rollers + a cone or cube causes it to fold in to that horizontal state you see it in most regularly. This is prime position for the arm to grab either game object from. When pulling a cone out, you can actually see the intake rotate a little as the grip on the cone it has forces it to move with the arm.
Here’s a video of me rotating it by hand to show how the intake stows when the cylinders are vented.
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So much to love about this robot. Looking forward to seeing it in Houston, and this time not just on display in the AndyMark booth.
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3940’s best robot yet by a mile.
Best of luck!
Side question - what grit sandpaper do you use to “frost” your polycarb? Assuming its just with a random orbital sander?
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Yep, random orbital sander, I went to check and realized we had been mixing 120 grit and 220 grit all season 
both seem to work, but 120 goes faster. We have really grown to like the frosted look on the LED diffuser strips and polycarbonate mechanisms.
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Just gonna leave this here
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