Hi, I am on a vex team and I need some help. This year is our second year working with vex and we don’t entirely know our way around a lot of the mechanical aspects of the robots. I was wondering if anyone could help me understand some of the uses for rubber bands on robots and why they are so important. Thank You.
One of the primary issues is with motors. First, they can’t provide so much torque, so you can use rubber bands to provide “neutral buoyancy.” That means you’re counteracting gravity with rubber bands so the motor only has to provide acceleration, not acceleration on top of countering gravity. Second, motors are not good at holding a position even when they can supply enough torque. So using rubber bands to provide “neutral buoyancy” means the motors don’t have to be run improperly as well.
Then there are other things. For instance, you want to build a ratchet or similar locking mechanism. You can use the rubber bands to pull to maintain whatever position needs to be maintained.
A use for rubber bands that was used a lot in NBN, is using them to tension a shooter. You could use them to shoot out a pair of anti-tip arms once a pin is pulled etc. Or, they were used in NBN to power ball shooters, since motors are not fast enough to push the fall with the speed to go across the field unless you used a flywheel. For this year’s game, as @callen suggested, it is probably best to use them to support your lift and reduce the strain on the motors. Or you could use them for anti-tip arms that shoot out at the beginning of the match if your robot is prone to tipping.
As @Easton and @callen stated, rubber bands can be used to support lift arms and on shooters, however, for adding tension to aid in raising the arms, I would recommend using Latex Tubing instead, as there is less potential for it snapping during the middle of a match, as it is a higher quality material. We have used it on all our robots for the past three years because of this, while we have not yet used rubber bands.
Rubber Bands, however, are used to wrap around metal claws and other pieces to increase the friction coefficient, thus providing a more “grippy” surface to make contact with stars, cones, cubes, and basically whatever else VEX could throw at you.
Hope this helps!