Servers by jDrones

No throttle in auto mode

I have Ardupilot 4.0 with Pixhawk 4 mini FC. It is a large jet drive boat with petrol engine, steering is operated by the jet nozzle.
All controls work well in manual mode but when set to auto no throttle is applied. I have done the motor test which also doesn’t operate the throttle. steering operation is good. The channel assignments all appear correct and I have tried the various suggestions linked with this topic in the forums. there is no safety switch set and the throttle arms correctly in manual mode.
The throttle is operated by a servo and no reverse function is required.

Does anyone have any ideas please? I am new to this and struggling for what to try next! thanks in advance for your time.

Kind Regards

After re-calibrating RC and adjusting throttle trim the throttle does come in during auto and loiter modes. It is however straight to max throttle set at 40%, cruise throttle is only 20%. Is this normal?

Another issue I have is RC signal loss failsafes, the throttle cuts back in manual mode when RC is lost but it isnt dropping out in auto or loiter modes?

Hi Paul,

I think it’s best if a log is downloaded from the autopilot and linked here somehow. Instructions on how to download are here. It’s all guesswork without a log I’m afraid.

Hi, thank you for your reply. This is a work project and it will be undergoing trials soon. I will try to get a log download if the opportunity arises. After more investigation it appears that my RC reciever doesnt drop the PWM level when the signal is lost, it either holds the last value or sets a higher one. Hence the odd failsafe behaviour.

On yet another query; is there a means of incorporating a jet bucket control (to reverse thrust for astern movement) in rover? this needs to be a variable control rather than just up or down. I cant see a way to do it.

Thanks again.

I’ve never heard of “jet bucket control” before but I guess from some searching that it could be a servo that allows the thrust to be reversed? I wonder how the variable control works though…

I don’t think AP Rover can support this at the moment but feel free to add an enhancement request to the issues list especially if you’ve got the actual hardware to help with testing. This likely isn’t something that I can work on in the near future but perhaps another developer could.

Servers by jDrones