[Andy A.]

I can only speculate as to why there is a (apparent) difference between the two flavors of spike. My best guess is that the reverse current protection is in the form of an optical isolation control system, at least in part.

An optical isolation system is pretty simple. Instead of the control signals effecting the Spikes circuitry directly, the signal operates a internal LED opposite of a photo sensor (or equivalent sensor). The sensor 'reads' the LED, and translates it into what ever state the Spike should be in. It's like putting a little remote control in the Spike. In this way, the RC is never directly connected to, or risks being connected to the robots main power. This is good from a safety standpoint and it cuts down on interference. It might also keep the delicate control electronics isolated from reverse current, although I would guess thats not the only protection used.

In any case, I don't know if the Reds were also opti-isolated. But, since the Reds and Blues are, according to IFI, interchangeable I'm guessing that regardless of the presence or lack of opti isolation, the control signal is the same, including power consumption.

Also, the '05 spikes look quite different then every other version I've seen. But, since opening a spike isn't something I've managed to do (I've tried!), I couldn't say what has changed inside. Probably little, if anything.

So why the apparent difference in performance between the colors? I can't say for sure. On paper, there isn't one. The opti-isolation theory strikes me as being pretty weak. Perhaps someone who knows a bit more about the inner workings of a spike could chime in with some ideas. If no one has the answer, this should probably be raised with IFI. It's kinda scary having 3 different control systems from IFI, and legacy Spikes that may or may not work on some systems. Makes me wonder about what else could crop up.


-Andy A.