Rudder Stick Arming not repeatable?

I’m testing the throttle arming options on my electric glider. I have ARMING_REQUIRE set to 1 and ARMING_CHECK and ARMING_DIS_RUD set to 0.

After starting up the pixhawk (3.0.3) and with the safety switch blinking, I set the throttle stick to around 40% and arm using the safety switch. I get a solid light on the safety switch and servo response but no motor, which is what I expect. Applying right rudder arms with the arming tone and I have motor control as expected.

If I then disarm using the safety switch, reset the throttle to around 40% and re arm with the safety switch, the motor starts immediately.

I would have expected the arming process to require the stick for each arming event, or has it been designed for only allowing control checking after initial turn on?

Davey, I am pretty sure the throttle must be fully closed when arming. Please add the information I will ask for below and an expert should be along!


There’s two kinds of arming, a) button (overall arming) and b) throttle arming with rudder. (It’s probably best to have the throttle stick at zero before arming a) and b) to prevent potential odd behaviour and uncommanded startups)

Once b) is armed by the application of rudder it can only be disarmed through the mission planner, if a) is disarmed and armed again, b) will carry through it’s armed state and throttle will be live again once a) is armed.

If you have b) set to arm immediately then b) will stay armed throughout disarming and arming of a), but will be ‘off’ when a) is disarmed and ‘on’ when a) is armed. Hope that makes sense? :slight_smile:

Thanks for your replies guys,

Gary, the hardware is all 3DR - Pixhawk, ublox gps, power module. Running Plane 3.0.3. I think the original post covers the other info. Yes, I was surprised that the motor would arm with throttle applied.

Graham, your explanation makes sense in terms of what I’m seeing. I agree that throttle should be closed for arming, but that’s what the safety is there for :slight_smile: It wasn’t clear from my reading of the docs that rudder arming only worked in conjunction with MP. I would have expected the arming to work such that if b) is enabled then a) AND b) required for arming, otherwise a). Maybe the safety button code should be disarming both b) and a) when b) is enabled.