Damped esc optimizations

If any statements I say are false, please let me know. I’m trying to better my understanding of the control system.

Years ago, before damped ESCs were common, ArduCopter had a problem where aggressive yaw would cause the copter to rise. The problem as I understand it was that 2 of the motors would be commanded to increase speed and 2 to decrease speed but the motors speed up faster than they slow down resulting in an undesired increase in net lift. A similar issue would occur on an over-tuned copter, oscillations in pitch or roll would cause the copter to shoot up into the air.

I believe a fix was applied to ArduCopter code that takes the output of the PIDs and does some processing/filtering before sending it to the motors. This fix solved the problem, but it also slows down control response. Could someone direct me to some documents describing exactly what this fix does?

Now that damped ESCs are common, motors are capable of slowing down as fast as they speed up. However, we can’t take advantage of this because of the fix that was applied. In my experience, I am unable to tune ArduCopter to fly as crisply (in acro/stabilize) as I can with CleanFlight on the exact same copter. I am guessing that the fix described earlier is the reason, but perhaps that is not true. Is there a way to disable this fix?

Or is there something else I can do to improve the responsiveness of my copter? It is a smallish quad, ~750g with 7inch 2blade props on T-Motor 2204 1400kv motors.

Thanks for your insight!

Can you be a bit more specific ?

I had been thinking of this video that I saw a couple years ago, but I guess I mis-remembered the details.

I thought he had said that the fix was aimed at compensating for motors that speed up much faster than they slow down. I guess what I’m looking for would be documents detailing what the “Stability Patch” does.

Since then, several severe changes have been added.

I would recommend going on the latest 3.5RC5 and work your way from there.