We want to project our arm that will hook on the castle tower’s bar. We want to do this vertically using surgical tubing to lift the arm until it hits the stop at the top of the arm’s travel. It never gets “airborne” and stays completely within the confines of its mechanism. Our question is: Is there anything prohibiting using surgical tubing, stretched and secured at the arm’s base, as the means of extending the arm in the last 20 seconds. (we will have a latch mechanism in place to be sure that it won’t release until our driver hits the button.) Thank you.
You are specifically allowed to do this as per R35
What you need to be concerned with is R9
Inspectors will look very closely at your mechanism to ensure that it is safe at all times. This includes when it is being transported on/off the field as well as in the pits, etc.
If there will be a lot of tension put on the tubing, then you will need a safety mechanism in case the tubing breaks. Basically unplanned sudden release of stored energy must be taken into account.
In the past, encasing the tubing in tube would suffice. Make sure the outside tube has a separate attachment so that it won’t go flying off either.
From a practical standpoint, you probably don’t want to stretch the surgical tubing much past twice its natural length; beyond this it tends to stretch inelastically*, especially if held there for a long time.
that is, a permanent stretch, from which it will not return to its original length.
