Curious if the Pixhawk can only support servos at 1520μs? When I look at most tail servos they are usually running at 760μs. Will the Pixhawk support 760μs? If not what Tail servo would you suggest? 900 size machine.
You need to be a member of diydrones to add comments!
Replies
Just wanted to add a small note.
I replaced my YGE ESC for a Kontronik ESC and the tail wag is now gone! I have been fighting that tail wag for a long time. My guess is that the YGE has a hard time with its governor mode. You could here it pulsing to the motor.
Kontronik is the way to go!
Correct file
2014-10-24 10-29-13.zip
Any suggestions for tail a servos on a 700+ size machine?
Any reasonably fast servo will work. I'm currently using HK MIBL servos, and I have one of the 0.04 second ones on rudder. But sticking with name brands, something like a Futaba S9352HV for example should be more than fine.
IMO, a lot of the servo spec race is just marketing. Anything faster than 0.10 seconds is going to be fine. Right now, there are much bigger problems with regards yaw control right in the code anyway. It wags really bad when stopping, and it's not because of the servo.
I am running a Savox SB2272 @7.4V which is rated at .032 sec.
The helicopter has an under driven tail so I am dealing with a small tail wag. I got some larger tail blades I will see if these help.
That is more than fast enough. I don't think a 760uS servo will help at all.
The problem could be the IMU filter rate. Or your PID settings. Or the fact that the algorithm isn't quite right. I'll have to work on that but I don't know when.
I will redo my PID settings today and see how it goes. I think the larger tail blades should help.
Yeah, this probably possible hardware wise, but there are some blockages in the code that make it not possible now. I have not been motivated yet to go after this one, first of all because there are plenty of fast servos with the standard pulse-width, and second because I don't see the point of a 500Hz servo, when we're doing 10 or 20 Hz rate filtering anyway. IMO, the 760uS servos are a gimmick.
But, if somebody really wants it, it could be done.
@Sean,
I don't think it'll work although I've never tried. I'm sure the pixhawk can output pwm signals that are very short like that but I suspect we will have some limitations somewhere that will stop it from being below about 800.