Spin & crashed!

[cheddarman]

FD, what does PPMrecv stand for/mean in the CsvView Motor menu please?

 

[Gizmoh]

It's either a bad motor or a bad ESC.

Anyway to be sure if its esc or motor?

 

[sar104]

Thats the answer I was looking for. Wasn't 100% certain of the reason for the max PWM and motor slow down causing the spin. And agreed on the app messages as well. BTW, did you look at the event log? Specifically the first line here. Landing? Just curious. The remainder is after the crash I believe.

View attachment 115540

That's just referring to the RC command that stopped the motors.

 

[sar104]

Anyway to be sure if its esc or motor?

There may be, but I don't know what that would be. The data that show the problem could be indicative of either.

 

[cheddarman]

sar104, what does PPMrecv stand for/mean in the CsvView Motor menu please?

 

[Fly Dawg]

That's just referring to the RC command that stopped the motors.

I understand that, but there were 2 commands issued. Apparently only the second one worked. Point being is that the aircraft was already on the ground upside down when they were issued. Just looked odd....

 

[Fly Dawg]

sar104, what does PPMrecv stand for/mean in the CsvView Motor menu please?

You need to do your own acronym research. PPM ( Pulse Position Modulation ).

 

[cheddarman]

Ahh, thanks for that. I've always understood that ESC's operate utilising PWM (Pulse Width Modulation), when I was in electronics in the Navy they certainly did. not PPM which until now, as you realise, I'd not heard of!

Having now read about the two a bit more light has gleamed!

So with that gem of information and plotting the PPM signals to the motors, at the time of the in vitiation of the "falling" out of the sky at about 42secs, the front left pulses suddenly went to 100, maximin, and stayed there until ground contact. To me this would lean towards the ESC rather than the motor.
At 43.6sec the right back also started to get very erratic, presumably trying to compensate for the LF behaviour???

Your thoughts gentlemen, please correct me if my thinking is wrong..................

 

[Fly Dawg]

At 43.6sec the right back also started to get very erratic, presumably trying to compensate for the LF behaviour???

That was after the spin began. You can stop beating the dead horse now. There is really no way to know for sure which is the actual cause. The effects are obvious.

 

[sar104]

Ahh, thanks for that. I've always understood that ESC's operate utilising PWM (Pulse Width Modulation), when I was in electronics in the Navy they certainly did. not PPM which until now, as you realise, I'd not heard of!

Having now read about the two a bit more light has gleamed!

View attachment 115543

So with that gem of information and plotting the PPM signals to the motors, at the time of the in vitiation of the "falling" out of the sky at about 42secs, the front left pulses suddenly went to 100, maximin, and stayed there until ground contact. To me this would lean towards the ESC rather than the motor.
At 43.6sec the right back also started to get very erratic, presumably trying to compensate for the LF behaviour???

View attachment 115544

Your thoughts gentlemen, please correct me if my thinking is wrong..................

If the ESC increased PWM for more motor speed and the motor did not respond, then doesn't that suggest a motor problem, rather than an ESC problem? Unless the ESC was misreporting, of course.