[RyanCahoon]

I see a couple of different issues here:

R-F interference from external (i.e. not from things on the robot) sources and/or other electrical devices and/or electromagnetic fields from the motors. I assume most of the COTS components would be standards certified for this kind of interference. Any custom circuits might have to take this into account, but like [CalTran] says, providing some distance between the electrical components and sources of strong EM fields would probably be sufficient. Alternately, shielding (tin foil?) tied to ground I would think would probably be effective. Running longer wire runs in twisted pairs can also help with this.

The other would be voltage transients in the power system caused by inductive properties of the motors. I assume there is some filtering being done on the digital sidecar and the analog bumper as part of the 12V->5V conversion to help with this, but somebody more familiar with the design of these devices would have to comment on specifics.

I don't see how grounding the robot frame would help with either of these (correct me if I'm wrong). In an automobile, the frame is encompassing enough to perhaps provide some Faraday cage-like effects, but I don't see this being the case (in general) with FRC frames - if nothing else because they're specifically designed to use as little material as possible. There is existing discussion on Chief Delphi as to why automotive manufacturers use the chassis as ground this but FRC explicitly forbids it.