AC 2.0.39 beta firmware feedback

Yesterday I updated Mission Planner and loaded up build 39 onto the APM. This is what I observed after a full erase/setup (I have sonar and mag) -Did an initial test on the sonar to see what the new values would be by having the motors running on low throttle and holding the quad over the ground about 1.5m up. Values in the log look more accurate however the values alternate up and down about 50cm over each 20 or so log records. Looks like a mountain range.I then took it out for a fly.When I flicked the switch to flight mode and plugged in the power there is about a 5 second inactivity on the status lights followed by the A and C alternating (GPS not locked yet). As expected due to the changes in the code the APM does a level when I arm the motors. After the arming procedure lights had finished flashing the C led went out and I was left with just the A led. Could not get the motors to kick in.I then disarmed and the C led started flashing. I then armed and the C led then went solid. When I then placed the quad on the ground and lifted off it was stable however the yaw was not holding at all. It was just wondering constantly left or right depending on the direction I nudged the yaw in.I landed, disarmed, armed and took off and had the same thing.I landed, disarmed, unplugged the battery, plugged in the battery and had the same issue with the arming light going out. This time I pressed the reset button. When I did that I was able to arm however when I took off there was no stabilisation at all so could not get it to fly.I unplugged the battery. When I plugged it back in I was able to arm ok and the quad took off and was stable AND the yaw was now holding fine.I then tried alt hold at about 1m off the ground. This time it just shot up and didn't look like it would stop. Even after flicking back to stabilise it seemed to keep going so had to drop the throttle to get it back down. So it still looks like I will have to keep mucking around with the sonar placement and change over the cable so it's only shielded to ground on one end.Also noticed two of the prop savers are not perfectly centred so will see if I can eliminate the vibrations from that as well.

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  • Just went out for another fly with updated PID values for alt hold and that lack of heading hold issue has come back. It's like the magnetometer is dead. Even when I flip to simple mode it has no idea which way it is rotating - which led to an inevitable crash. My ply arms don't really cost anything apart from the time it takes to reattach everything that goes onto the replacement arm. It's just a very annoying process when you go to test one problem out and end up with a different one to spoil your day.

    Jason, when I get a chance I will upload the last log to see if you can spot what the error is.
  • I Repositioned the sonar out on the front right arm (motor 2) in X mode so that it sits about 6cm below the arm. I also wired it up again with a shielded three core. Attached is the brief log I recorded with the engine on low throttle and holding the quad about 1.5m off a hard surface. Still seems to alternate up and down about 40cm.  Does this get filtered out in some way? Curious to know what Omega Z is recording as it almost looks like a representation of what the sonar should look like.
    Will try alt hold again in the morning

    02-08-11 06-16 15.log

  • Ok Jason, now that we have established that 2.0.39 was not fit for human consumption I've gone through the same routine for 2.0.38. What I now see is the same issue with the arm light not coming on after the IMU init after arming. If I disarm and then arm, the armed light comes back on, unfortunately heading hold does not exist. It's stable however it wants to rotate either CW or CCW and never lock onto any heading.
    If I hit the reset button and then fly again, same issue. If I then unplug the power and plug in again I do get the solid arm light after IMU init and finally I get heading hold.

    So it looks like APM is going through some form of magnetometer calibration for your first flight. Should we be just holding the quad with the motors not running and rotating it in all axis after the first motor arming? Is this the behaviour you were expecting in 38?

    Alt hold still shoots the quad into the air however I've still got some work to do on the sensor placement/cable.

    Stability is better however that might have been the change from the 10x6 to 12x4.5 props which seem to give me more air time.
  • I unfortunately used the MP and it downloaded 2.39.  It flies well but I noticed before I flew that many PID values in the Config were changed extremely and I had to re-write the correct values.


    Will I be able to use the MP to re-load .38 soon?

  • Developer
    I didn't realize 39 got into the planner. It's on the SVN but it's not ready for consumption.
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