How to power an endgame mechanism

Currently this is my rough estimate of what I wanna do for endgame. Basically I will have string (stored on the axle at the bottom) attached to a rubber band that will be pulled back towards where they all converge and then released. I was wondering what the best way to do this would be? I am using one motor and I don’t want to put too much tension on it.

Look at doing something like this but with a motor instead of pneumatics


Yeah I saw that video! I was thinking of doing smth like that with a gear coming from a motor that pushes one of those green gear strips on a T like piece of metal instead of pneumatics?

the rough idea is this, right:

  • String is tied to the rails on one end a bunch of rubber bands with a weight on the other.
  • There are studs/standoffs/screws - posts, in other words, near the center of the fanned rails
  • a plate with holes for posts rests on the center of the fan
  • String rests on the rail
  • Rubber bands go over the post and then to a catch on the rail - could be another post or even a step in the vex part
  • That plate will move up and push rubber bands off the posts, deploying strings.

As for how: you can use pneumatics or you can add a bar that is geared to a motor to turn it and release the strings that way. The other idea I thought of recently is to use 2 short linear slides, put them on posts on the edges of that plate, run an axle through 2 small gears that will ride on racks on said slides to raise them when the single long axle is turned by a motor. This is relatively bulky.

This is the style of expansion my team uses but the strings are annoying to wind up and the consistency is lacking.

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Since we only have a couple days left before competition I settled for dropping a wall that expands and has string attached so we can drive away lmao. Not quite as efficient but we don’t have time to troubleshoot

understandable but this mechanism was deployed in 1 day with 2 people working and 1 programming for no more than 1 hr on our team.

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