Hello all,
Thanks in advance for your time. I’ve come across a new problem that I have been unable to diagnose.
I’m building a little tank set up that I want to be small, its running two geared brushed motors, and I’m using these brushed ESCs to control these motors
I want to run this from an RPi with a Navio2 hat that’s running ardurover (v4.0) on a non-specific frame type (0). I have previously got a bunch of brushless motors running in both copter and rover frames with varying success, but at the very least I could get the motors to turn as I wanted. Not in this case.
I think the problem is with the ESCs but I am having difficulty finding any documentation on them. The ESCs are bi-directional, no brake, and should power the motors I’m using easily. I have the ESCs powered and connected to the RPi. I’ve noticed that when they are powered but not connected to a 1500 signal they blink quickly, presumably to tell me they are not armed. When connected to a signal of 1500 they blink slowly, as I’ve seen in a number of videos where they have worked.
I am connecting to this set up through mission planner, over the wifi, using a joystick to over-ride the RC inputs (it has no transmitter for now). I’ve done this previously and its worked fine with other frames. The problem I am having is that the ESCs do not seem to respond. Other videos I have seen show the ESCs show a solid light when commanding the motor and emit a little beep when direction is changed.
What is strange though, is that if I turn the ESCs on and immediately issue a command they will respond for about the first 3 seconds - allowing me to drive the motors, change directions, and the lights work as I describe above. After about 3 seconds (although it’s variable) the motors stop, the ESC goes back to blinking and it no longer responds to inputs. ’
I include a short video of this here where you can see the video starts with the power on to the ESC, I toggle the power, and push the joy stick left on my controller (you can see mission planner showing the command change in the background). When I push left the track spins as it should for a few seconds and then stops, with the ESC returning to a slow blink, and the command still visible in mission planner behind it.
My only lead is that the ESC does say it takes a PPM input, and produces a PWM output. The Navio2 hat produces a PWM output only. I hadn’t noticed this when I bought them (thinking they were PWM in) and thought this might cause issues. It seems the ESC still reads the PWM out from the Navio and can command the motor if only for short periods so I’m not sure this is it.
The only other thing I noticed is that sometimes after the ESCs stop responding it throws the drone into a disarmed state. The log in mission planner did not show a reason for this, but did also say the drone was now in a disramed state.
Any help appreciated - I’m still learning on these.