you are corrent @gnitzan
also after replacing burned motors or ESC try to test all your motors and ESCs in mission planner motor test to make sure all of your motors are ok
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Thanks @hosein_gh, actually I did motor test last night and all was well with no problems, I set test up to 50%.
Actually, I am not 100% sure what went wrong, because from telemetry, the motor was not stressed out, its temperature was like the other motors, so maybe ESC?
I will take it apart and check everything.
I have done nothing at home except removing the props and broken legs.
Here is some test I did which shows nothing is wrong, any input would be highly appreciated
Test on workbench
Without propellers you can’t put you motors under full pressure
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Hi, I have tested with props on (upside down and rotated like for comp motor calibration) and all seems fine.
Log seems fine
so it seems I am still at square one.
I did a video in my test, it is still uploading to DropBox, I shall link to it when ready.
yes now your log is good
so check all ESCs and motors wires and do a test flight with 1m altitude
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Agree with motor- esc failure;
if you cant find it; what I do: don’t try autotune until you be shure your failure was solved, put an extra protect thing under your quad, a X like student pilots use or a soft extra improvised legs near the motors to avoid flip and broke props and then try to fly near the floor over soft terrain for some time loitering, then doing soft movements pitch and roll, use all the flying time your batt allow, see what happens and share your log to see if any of Us can detect something after the next autotune, good luck.
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For all who are interested.
I did yesterday in perfect weather a Autotune with a newly build Hexacopter ( 4kg).
FW: ArduCopter V3.6.10 FC: Pixhawk 1.0
Carefully balanced and trimmed, but using default PID,s
Takeoff in stabilize, switch into PosHold and than Autotune. Setup not aggressive but all 3 axis in one go.
Total time exactly 10 minutes. After saving the Autotune values I tested the Hexacopter in all modes and it is flying perfectly.
Need a test in windy conditions only.
I cannot find any problem with AC v 3.6.10.
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I am relatively new at analysis, but does the log analyzer reveal anything of interest to your initial experience? I note the change of mag field, or is this perhaps an artifact from the crash?
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Hi Jack, actually I didn’t look at the log analysis, my bad. As you mentioned, it’s probably from the crash since I did a calibration right before takeoff.
However, THR_MIN not found and current not available I will. Anyway, good catch.
Thank you
Gal
Crashed again.
I was flying in LOITER at about 1-2 meters, very slow. Initially pitching and rolling harder and harder without any problems.
The second I touched yaw, it dropped to the ground. Luckily because of the height, nothing broke.
Attached my log on Dropbox.
Any insight would be appreciated.
Gal.
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yes unfortunately your motor one stopped after changing yaw
lets test this problem on ground
arm motors in stabilize mode and rise throttle a little bit (we are not going to fly) when your motors rpm rised , change yaw stick and see whats happening (motor on will stop sniping or not)
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Hi @hosein_gh, something doesn’t make sense to me. Rcout is the pwm command sent to the motor, is it not?
In that logic, why did the fc sent this command?
Or I am totally don’t understand?
Thanks
RCIN is the pwm input by your radio and RCOUT is pwn output by FC to ESCs that trimmed by radio calibration (and some other params only in auto modes)
in the picture above when a motor or ESC stopped working FC automatically will put burned,stopped or damaged motor to max throttle and opposite motor to lowest throttle to keep the balance of copter but this method are not working with a quadcopter but in hexacopter and octocopter working well for example if one of the motors of a hexacopter stop working FC will stop the opposite motor and now hexacopter is converted to a quadcopter and can fly and land without problem
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This is a very common misunderstanding of closed loop control. Rcout is the command signal as you state. If the feedback from the command is not responsive it will increase the command. And so on until full throttle output. Then logically the opposing motor output is decreased in an attempt to stabilize the attitude.
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Thank you all for the elaborate responses, now I can truly say I learned something new today.
I just returned from the field where I tried initially @hosein_gh way and didn’t have any problems.
So, I changed to Loiter and took of to about 1 meter.
I started to do very light P/R and after that yaw as well, there was no problem.
Than I just let it hang in the air and after a minute or so suddenly it twitched really hard for a second and it regained control, that’s when I landed.
So, now I need to decide if it’s the ESC or the motor. The ESC is 4in1 F55A from T-Motor.
Or do I need both?
Thank you
Gal
An idea to try: tie the quad with rubbers so can fly without crash risk, determine what motor fail if you dont determine yet, then rotate the motor with another one and try again to see if motor fail in another position or esc fail in the same position to determine who is the culprit
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@gnitzan as you said
do you set everything in this page step by step ?
http://ardupilot.org/copter/docs/tuning-process-instructions.html
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@cala2 excellent idea, since I already know it’s either motor 1 or esc 1…
Great, that’s what I shall do.
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