Torsion Springs

Does anyone know a reason/rule that would prevents us from using torsion springs to provide the motive force on a kicker mechanism?

Most rotation kicker type mechanisms that I have seen here are using the surgical tubing which take up a lot of space. Our thought is properly sized torsion springs at each end of the kicker axle could do the same job and not require the robot space that an extension type spring would require.



From my reading of the rules, the only things that would prevent it are if it’s unsafe, or if you use illegal materials (ie. make sure you use springs that any team can buy).

Neat idea! and there are a lot of them available from places like McMaster Carr

they also work well in the drivetrain

no it states in the rules that you can use them as long as they are safe.

Do Home Depot, Lowes, or any other local vendors carry a good selection of torsion springs or springs in general?

Our local Ace Hardware store has some, but not nearly the selection you probably need to do it right.

Under <R01>
Teams must be very careful when incorporating springs or other items to store energy on their ROBOT by means of part or material deformation. A ROBOT may be rejected at inspection if, in the judgment of the inspector, such items are unsafe

I would suggest that you bring along the specification sheet for the spring you intend to use and have it available during inspection. The inspector will need to compare your use with the sheet. We are just as concerned with overstressing the spring during charge as we are as to what happens in a dry fire. Springs do have a tendency to shatter under conditions beyond what their design intends. Inspectors tend to err on the side of safety in these issues and may involve the UL Safety Advisors much as we did with propellers last year.

Al, that’s another good reason to order the springs from a supplier like McMaster-Carr…they have the specifications on their online catalog.