Is it possible to run CubePilot without an RC receiver?

Cube Autopilot
1

Hi,

I’ve been unable to get my RadioMaster ER6 receiver (ELRS) connected to my CubePilot Orange+ and get it working in Mission Planner. All I want to do is control the UAV (RC plane) from the ground station using a joystick (got that configured successfully in Mission Planner) and data radio (RFD-900x), and use the RC transmitter as a backup to control the plane in case the RFD-900x radio link has a problem in flight. Is it possible to get the CubePilot to arm and run successfully without an RC receiver hooked up to it, and if so, how? Right now I cannot arm because it says ‘Waiting for RC’…

Thanks,
Paul

2

So I ended up with a temporary workaround by setting ARMING_REQUIRE to 0 in Mission Planner, so it bypasses all pre-arm checks (like checking for an RC receiver) and arms the autopilot. But other features appear to be dependent on an RC receiver being connected and working (like I’m unable to get the USB joystick to control the servos, maybe because no RC receiver). So I’m back to the drawing board trying to figure out how to get an ELRS receiver talking to CubePilot Orange+ and Mission Planner… I’ll search the threads some more or start a new thread.

3

Yes, it’s possible to disable the RC failsafe but this is not recommended of course.
The problem you have is the ER6 receiver outputs 6 individual PWM channels and:

  1. this is really not enough channels
  2. there’s no input for individual PWM channels (only SBUS or PPM)
  3. the serial port is not used and there is conflicting information - assume it does not work

Get another receiver that works as per the Ardupilot doco, such as the RP4TD diversity receivers, or RP3-H which has a case.

There are some important considerations:

  • Channel 5 - set your transmitter to always have ch5 high (~2000pwm) as this tells the receiver the aircraft is armed and to come out of low-power mode - avoid using any other functions on channel 5 unless you REALLY want to use an arming switch (with all the special considerations that come with that)
  • Set another channel to Flight Modes, eg: Ch12 FLTMODE_CH,12
4

Good info, thanks. That is what I’m experiencing, that the ER6 serial port just does not work for CubePilot, so I will try that Radiomaster RP3-H receiver… By the way, this is for a fixed wing plane, so I just need aileron, elevator, throttle, and rudder control for now; but I will configure the channels like you recommend.

Thanks,
Paul

5

Solved: the RP3-H ELRS receiver works with CubePilot Orange+ when connected to a UART (Telem2, UART3 in this case) using CRSF as the protocol. I configured SERIAL2 and other parameters as identified in this page:

RC input now works (can arm, RC transmitter input works, no “Waiting for RC” warning, etc.).

So the ultimate answer to the question of whether or not you can run CubePilot without an RC receiver is: yes, but you will not get any of the autopilot features or RC control, and probably not USB joystick control either. CubePilot would only function as a sensor (attitude, altitude, GPS, etc.) without an RC receiver.

6

You can use Ardupilot without an RC input via telemetry radio once everything is configured and tuned. To get to the “tested and tuned” stage you need the RC input.