pic: Team 1511 Prototype Drivebase Mk. II

[Vespasian]

Originally Posted by Arpan

Consider the momentum of a fast-moving FRC robot. Cylinders aren't really designed to take side loads. Are you concerned about bending those cylinders if hit?

What do you do if you lose pressure? Will the bellypan drop and prevent movement?

Rs775s have been used on drive trains by teams before, but be careful. Running those motors near stall for a long time will fry them- they are fan cooled, as opposed to CIMs, which are passively cooled and rely on a large thermal mass to keep from overheating.

As for the side loads, it is a concern, but each cylinder only has a stroke of 1" at 5/16" bore. They could bend, but it would take a considerable amount of force. These are relatively easy to replace in this design, though I would rather not have to keep extras lying around, since they're not too cheap.

Currently, there is no redundancy in terms of pressure loss. For our build season design (assuming the game is conducive to this system) we will probably have four smaller "feet" drop down instead of the entire pan. This gives the advantage of having rigidity from the pan, and less room for catastrophic failure. On that note, does anyone have a suggestion on what to do in case of pressure loss? I was thinking maybe surgical tubing to pull against the "feet" or bellypan with just enough force to lift them off the ground.

I have heard many concerns about stalling RS775's for too long and frying them. If they are too much of an issue, we could replace them with Mini-CIM's or just take them out altogether.