Welcome To DroneVibes

DroneVibes is a COMMUNITY of drones enthusiasts. We are experts at drones for all professional and consumer applications. We welcome you to register and join the conversation.

Motor #3 revs up with no real reason ?

Discussion in 'Beginners Drone Forum' started by T3raHerz, Jan 9, 2019.

  1. T3raHerz

    T3raHerz New Member

    Jan 9, 2019
    Posted by T3raHerz, Jan 9, 2019 #1
    Hi, I'm getting vibes, literally.

    I'm building my 2nd drone out of parts and just when I'm ready to take off, I got this weird problem. I see some people out there have had this same assuming it's a common. There were some threads on other sites of similar problems but threads kind of ended and there were never a real answer.

    I'm running on CleanFlight and all settings are done, Drone looks functional on screen and Tx channels are mapped correctly, sensors calibrated, motors spin correct direction, props OFF while testing on bench. Now the issue, simple. When I keep it on table, in my hand or just on ground, immediately when I throttle slightly up out from idle zone, motor 3 revs up continuously by itself and all others are just near idle. When I pull back tx to idle motor 3 drops to idle speed, again when I go out from the idle motor 3 revs up again. I tried to keep it in my hand and let the drone go on its direction where it want to tilt, motor 3 just doesn't change its rpm just remaining high rpm. (Why FC doesn't control it when gyro show its tilting? ) And yes 3D modeled drone on my screen acts precicely as it is suppose to aswell does my transmitter controls it correctly, and FC points forward, so nothing really is messed up...
    If I try to do the same with props ON, no change in results !

    In this video I first run it by master control to see that the motors spin correctly, then I arm the FC with tx and first manualy rev up @0:20, (as well motor 2 does not want to rev up at all???). Then @0:25 and @0:34 I exceed slightly the idle speed with tx and motor 3 revs up by itself up till 1280. Then I pull back to idle limit and motor goes to idle again. Something isn't right, motor 2 and 3 behaves like no sense. More severe is that motor 3 revs by itself which eventually would flip the drone with props. Sensors are calibrated and all checked dozen times but no clue.

    edit: This cant be that FC is actually on its leveling PID loop. PID loop is much much quicker than few seconds to compensate the position error. As you see in that vid motor#3 takes seconds to reach its limit it finally reaches. If this was positioning loop, motor would do it in fraction of a second for quick compensation. Same thing happens if there is props or not, is it on the ground, table top or in my hand. Tilting the qud any direction has no effect to motor#3 behavior. How does this sytem work?, is there a limit when leveling compensation takes action, so low RPM is not using PID loop? Or what does this tell you ?

    Race 32 Racing Flight Controller F303 (Deluxe)
    Turnigy D2206-2300KV 31g Brushless Motor
    Turnigy Multistar BLheli_32 ARM 33A 3g Race Spec ESC 2~5S (OPTO)

    Last edited: Jan 10, 2019

Share This Page