I am building (slowly) a 2 wheel hanging pendulum robot that uses 2 26" Bicycle wheels and Kelly reversing controllers.
The problem I have is that the controllers use a pot or 0-5 volt input for a throttle and not PWM pulse width.
While I am initially configuring the robot I would like it to be testable with an RC radio system only.
And for this what I would like to do is provide the simplest hardware conversion of the RC receivers PWM output directly to a 0 - 5 volt throttle signal.
The typical - simple RC filter approach for converting PWM to a voltage level won't work because the Radio Control PWM output signal is not a zero to 100% PWM pulse.
Rather it is a long low pulse with a short but variable high pulse the second half of which defines the 0-100% state of the PWM.
This is probably doable but complicated in discreet components (Op amps, pots and capacitors), but messy and is not something I think would be worthwhile to undertake.
Certainly it is doable to edit the Pixhawk code to allow it to drive a digital pot or D/A from I2C and that is what I am planning on doing eventually in any case.
But if anybody knows of an existing (module) specifically designed to accept a radio control style PWM signal as input and provide a variable voltage as output that is what I would very much like to implement at this stage.
I have looked but been unable to find anything online that can actually deal with a radio control style PWM input.
There are plenty that will take a zero to 100% style PWM input (including a simple RC circuit) but none that will deal appropriately with a radio control style PWM.
Any help appreciated.
Failing this I will simply start with either my Pixhawk or - more likely - my Beagle Bone Black.