My design capstone project will (hopefully) turn out to be a RC and autonomous rover controlled using a RPi 3. Right now, my team and I are thinking of using a pair of the simple high power motor controllers coupled with two 7.2V sub-C battery packs. I have two questions and am looking for any suggestions/recommendations:
- Would the 4WD or 6WD better suit our needs? Our robot must fit within a 1.5 foot cube (so the 6WD is only 1.5" under spec), but the 6WD seems more stable and gives us more room for components. The 4WD seems less stable, but smaller is always better, imo (and may be easier technically speaking, in terms of connecting motor drivers?).
- The Pololu Dual MC33926 Motor Driver for Raspberry Pi (Assembled) seems like a good option for us as an easier implementation for our motor driver, but I’m not sure if this option is better than the simple motor drivers (recommended to me over the phone with Pololu support)?
Any information would be greatly appreciated, as I want to get the ordering just right!
We spoke on the phone earlier today, but for anyone else reading this thread, I will briefly summarize what was discussed.
The choice between the 4WD Wild Thumper and the 6WD Wild Thumper is ultimately up to you. It is true that you could probably get away with a less powerful motor driver if each channel only needs to drive 2 motors instead of 3. However, the 6WD version is a bit bigger and better for scaling inclines or traversing larger obstacles.
As far as the Dual MC33926 Motor Driver for Raspberry Pi, since you would be running multiple motors in parallel on each channel (as I mentioned before), and these motors can draw upwards of 6.5A each (at 6V), the MC33926 is probably not a good choice. While it is a pretty robust driver, we generally recommend choosing a motor driver that can handle the combined stall current of your motors. In the case of the 6WD Wild Thumper, it is unlikely that all 3 motors on one side would stall, but it is still worth considering. A pair of Simple Motor Controllers is probably a better option, and as a bonus, they can be controlled directly from hobby RC signals or via USB, which might come in handy for your application. If the RC input is not necessary, another option might be one of our G2 High-Power Motor Drivers for Raspberry Pi.