[Paparazzi-devel] Strange throttle behavior

[Simon Wilks]

Hi

I have been noticing what seemed like a lag in throttle control though I wasn't 100% sure till my first test flight today (octocopter, lisa/l, spektrum satellite receiver). While on the ground I don't seem to notice this effect but when holding it above my head or lifting off strange things start to happen.

When holding it above my head changing the throttle on the sender seems to take a second or two till it happens on the copter. I have also noticed what seems to be a general increase in throttle all of sudden, not just to correct attitude but like a it wants to pull up and away. 

When I tried the first flight today I got a bit of a shock when I wanted to just lift off a bit then set down only to discover it did not want to respond to the fact that I had returned the throttle back to zero and skipped off across the garden. In the end I had to flick the kill switch. Pretty funny after the event. I have a video if you want a laugh here. 

You will see the props rotating at minimum speed (zero throttle on the sender) after arming. I assume this is correct? One of the props isn't rotating properly and I suspect it might have a problem and need swapping with a spare (it has a bit more resistance to the hand when rotating than the others) but I thought it might be OK to try a small hover anyway.

Any ideas what causes this kind of throttle behavior? Pitch and roll seem pretty responsive. Here is the aircraft config.

Thanks

Simon