The basic Afro ESC doesn’t support enough voltage for my needs (the \nsolar panel can deliver as much as 22V). I tried the Spider ESC, but it \ndoesn’t support reverse and I can’t flash it (furthermore, it’s a bit \ntoo hot for my taste). Luckily, there’s a “high voltage” (8s) version of\n the afro ESC, astutely named afro_hv. I got one of these, but it ships \nwithout reverse_pulse, that is the ability to go forward and backward, \nenabled. So I had to flash it, which was very easy using RapidFlash and \nthe AfroESC USB programmer.\n<\/p>\n\n\n\n
On a totally different matter, I tried several frequency for the \npower sampling loop, and after a few problems and Fourier transforms, I \nsettled on a 1kHz frequency: I’m using an ACS 712 based breakout for \ncurrent measurement and a voltage divider vor voltage measurement. I had\n a very unstable measurement with the motor running, that I first \nthought was provoked by uncontrolled noise (magnetic ?) around the ACS \n712. However, when calibrating with a resistor, I had a very stable \nmeasurement, thus leading to the evidence that the “noise” is actually \nthe commutation of power inside the ESC \/ motor pair. I sampled at \ndifferent frequencies, and got something stable around 1kHz (initially,\n I was using 10Hz…), which coincidentally is the sampling frequency of\n the ESC.\n<\/p>\n","protected":false},"excerpt":{"rendered":"