[Tristan Lall]

I disagree with Jack that it violates <R31> as written, however, it clearly violates the spirit of that rule, for whatever that's worth when it comes time for the inspector to make a ruling. Part of the problem is that circuits are defined in the rules in electrical terms ("as long as the electrical system is not modified", etc.), rather than (more comprehensively) in electromagnetic terms. What we really ought to see from FIRST is a clear indication of what modifications to the motor's magnetic circuit (which includes the ferrous metal case of the motor) are permissible. This would also instantly clarify the legality of 190's lathed-down CIM housings. Personally, I'd like to see something like "additional magnets, ferrous metals, or field coils (whether separately excited, or energized by the motor's magnetic field) are not to be placed within 0.25 in of the outer diameter of any motor, if their presence would cause a significant change in motor output", along with "modifications to the motor housing are permitted, provided that they do not cause a significant change in motor output or compromise the structural integrity or safety of the motor".

Returning to the original proposal, it seems to violate <R53>, which requires that custom circuits may not "[d]irectly affect any output devices on the robot, such as by providing power directly to a motor", though I suppose that a question could be raised as to whether "directly" includes magnetic fields, or merely refers to electrical conduction.

I don't think that this circuit exactly conforms to the intended applications listed in <R52>, but because the rules do not state "if it's not included, it's not allowed", we can only note that it doesn't conform to the stated intent. (Perhaps "may" should become "may only" in the second sentence of that rule.) Also, the sense of the term "outputs" looks like it means electrical outputs (judging by context), and therefore wouldn't cover the magnetic field.