While hovering I noticed all motors shut down few times and started again after about 1sec. I power AP board, Reciver and Roll/Pitch servos separately from different ESC BEC (with common GND only). There shouldn't appear brown outs. So what's the reason? [APM CPU 2560, soft v2.5]. Could it have something to do with bad Yaw and Throttle PID settings?
It's definitely not Lipo fault. It happend many times and by full charged battery. I set all ESC to low cut off mode to protect from sudden crash. . I can clearly feel in the flight the lipo is nearly empty and have some time to land (similary to my helicopters).
You have it set to low cut off?
That generally means that at low voltages (lets say when you give full thrust, 4 props all draining a battery at once) the ESC's may shut down/ slow down (depending on ESC) to protect your lipo battery. You want to set the ESC to NiMh, but be careful to not drain the battery below (3.7 volts per cell? I think).
I'm assuming you already know all this as you seem to have background in RC. Sorry to bore you but just stating what I've read incase the next person comes along and reads this.
I believe that this makes the most sense as your brain/receiver are all independently powered and don't have a cutoff at all.
Can you replicate this issue without props on while holding it and throttling it? See if certain actions cause the issue. Just my 2 cents.
I know exactly what the low-cut off means :)
I made some test without propellers and all motors worked smoothly, Meanwhile I turned the frame in all direction, set throttle in full range and all seemed to be correct.
Are you using Xbees or 3DR radios? We've seen interference from Xbees cause throttle cutouts before (solved by moving the Xbee further away)
no I'm not. I removed also the servos and problem still exists
your motors used hall sensor?or other?
maybe the problem is your motor driver.
I have the same problem. After I loaded the latest firmware 2.5 i have the same problem. It cuts all motors for a split second, enough that i had a hard landing and broke 3 props and landing gear. I'm as well using an old APM 1280.
Same "problem" for me. Since the latest 2.5.4 I have also motor shutdown problems. It can be a very short interruption on all three motors (tri-copter), but it can also cut it for a longer period so my tricopter fell from about 10 meters high. I was able to turn the motors on again. So no need to reboot or re-arm the motors. Haven't had this with the 2.5.3 version. Hope this will help to track down the problem. APM 2560
Exactly the same APM (2560). After shutdown all motors could start again after I changed a little thtotlle stick position. Could you repeat the test without propellers ?
..and you're definitely in stabilize mode right? You're not in Alt-hold of course?
yes, it happed in stabilize mode. I control altitude with the throttle stick but I didn't test it in other mode. Maybe someone else?
Do you have any logs? Also are you using APM1 or APM2? Do you use an xbee?
thanks for the report.