Traditional Heli governor question.

Hello everyone!
I have successfully used Pixhawk on my plane with auto mode in missions(via MP).

Now I decided to try it on nitro or gas helicopters but I still cant figure out how to use it with external governor (for example futaba 701 or another one).

It takes a lot of time to get necessary rpm to take off and start flying. So If I create any mission in MP and turn into auto mode, how pixhawk determine that it get right rpm for flight due to lack of feedback.
I afraid that it can begin taking off earlier than reaching right rpm wich will lead to crash.

Is there any way to set timeout for engine to get rpm that are needed before taking off or another way to solve this problem without editing the code( I am dummy in programming).

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  • Hi 

    I was wondering if you were using a custom version of arducopter since it does not support the H4 configuration of the vario helicopters by default.


  • I am using a Futaba 701 governor on my pixhawk controlled Vario helicopter. You have to set up the RSC ch 8 function for pass-through and you can also use the new RSC idle and RUNUP time in AC3.3 to ensure that the rotor head is at operating speed before takeoff.  I have the governor set to kick on above 30% throttle position.  

    This is my takeoff procedure:

    -Engine start

    -Flight mode = Loiter

    -Throttle stick to MID 

    -Wait 5-10 seconds until rotor and engine are spooled up

    -Flight mode = Auto 

    Hope this helps 

    • Hi Chris, thanks for helping out.  Just a note that H_RSC_RAMP_TIME and H_RSC_RUNUP_TIME are not new, they were around at least in 3.2, if not earlier. 

      Dmitry, yes, without having a sensor, there is no way for the Autopilot to know for sure.  The Runup time is a simple timer.

      3.4 will have internal governor and direct rotor speed feedback.

      • That's great to hear about 3.4. Will governor sensors work such as the stator gator? Any idea on when 3.4 will be released?

        • Any sensor which generates a 0-5V pulse should be able to work.  Actually, the pulse counting code is already in 3.3, you might notice some parameters called RPM_* One of them is for scaling, etc..  And you can even see the data in the logs.

          But the measurement code was not finished for 3.3, and I've made some improvements for what will become of 3.4.

          I actually have all my governor code working on a special firmware which is basically just 3.3 with the governor code added. I use this on my own gasser.  I might be able to provide this if people want to try it out, with the understanding that it is still a Beta feature.

          I would actually appreciate any willing testers to find any bugs.  I actually have it running on my Trex 500 electric with the ESC in simple throttle mode, so you don't need to risk an expensive gasser.

          • Interesting.  I am using a stator gator with futaba gy701 on my Vario right now.  I'd be interested in trying this governor code.  

      • Before I wanted to use external governor too. Thank you very much for answer, I will wait 3,4 then.
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