OK, here is my best guess. I'll need to breadboard it out to get it working. It basically glues some reference designs (off of the Internet...beware lol) with some approaches that I've used for years together. I have to admit that I'm a little shaky in the MOSFET area, but I know I can get a design like this to work with some fiddling.
I would recommend to someone trying to get this to work to breadboard a SINGLE CHANNEL of it, maybe using the PWM on the BBB PRU to output signal to the optoisolator stage of the circuit. Or if you can find a solid pre-programmed PWM PIC out there (and there are quite a few smaller operators that sell ASIC-type preprogrammed PIC's with some operation or function on them...for example, hobby servo control is a nice starter design to mess with) to drive your isolated power electronics with some kind of off-the-shelf motor. *** Can you treat a propeller like a resistor? *** An interesting idea I had was to treat my motor-propeller combination as a true electrical component, looking at it from a power transfer perspective. What I mean by this is there are equations out there that model perfectly a propeller's force and a propeller's effective power transfer to the air it pushes, that I suspect that you can equate the electrical equations involved with the mechanical POWER ones for propellers (and the electromechanical setup of the motors used to drive them). An idea. But it would allow you to fully model a drone's power systems in a way I don't think heretofore done. OK here we talk about how to power the 3 voltage zones. You'll notice that I've chosen holistically to do it with dumb voltage regulators and this is a product of kinesthetically "knowing" the current draw on each of the zones. The BBB is probably a little more of a power hog than people give it credit for, though I can feel the heat coming off it to be not much, so I'm sure it can be driven off of VR. The PIC the same...very energy efficient so a 7405 will keep my workload low. Also added are some pulldown resistors (on the "optional" network) because I'm afraid my MOSFET's are going to "float" (they call it) and have the BBB to PIC issue worked out (you can float PIC lines because they have built in pulldown resistors). Again, untested. I don't use this term loosely. There is no guarantee that this circuit will even work at this stage. <https://lh3.googleusercontent.com/-bsKGGuckDZI/WJbcHZX_WKI/AAAAAAAAAF4/_fYnYOdEk-gN1hVCGdXQc7mPDSl549BTgCLcB/s1600/drone_mosfet2.png> On Monday, January 30, 2017 at 6:19:30 PM UTC-7, woody stanford wrote: > > I posted the remote control for this in Software, but I put a bunch of > hardware in it so I thought I'd post it here. > > > https://groups.google.com/forum/#!category-topic/beagleboard/software/evSIUcuWfUY > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/eea20b90-eda4-474e-8ab6-515f8689cd8f%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
