Searched and searched and haven't found much info on getting the tail to work on a TH. Just completed an install yesterday on a T500 and while the MR appears to work reasonably well the TR just wags back and forth and no amount of gain adjusting seems to make a difference. I read that the developers feel the tail now works properly so I'm looking for the hints on what to do to achieve that.
The "Gain" setting on the Setup page seems to do nothing. Is that only for an external gyro? Is the check box for an external gyro? I couldn't get the tail to operate at all without checking that box.
Also, how to set the tail mode separate from other axis. For normal helicopter operation you'd want either acro(rate mode) or stabilize(self leveling) for the MR and heading mode for the TR. How to do?
I spent some time browsing the source code last night (which amazed me at it's simplicity) but didn't come away with any revelations.
Thanks,
Ron
Replies
Ok, I'll try this. Here is my Parameter file.
Setup 14.param
What is going on? I could swear I made a post last night and uploaded a screen shot of my setup in APMP.
I'll have to try again.
What exactly is "TH"?
Now, it says unless you check that box the tail "doesn't even work". What exactly do you mean by that? The tail control will feel a bit peculiar to those used to external gyros.
First, the tail servo will never move if the throttle is at the very bottom. It's a safety thing for quads, we're going to try and fix that. So, disconnect your ESC and try throttling up.
It's also possible that when you're in Stabilize mode, if Stabilize_Yaw P and I terms are zero, it might not move if you input some rudder stick. It may still respond if you push the tail around however. I haven't actually tried that test.
I have the system installed on a T600 with no external gyro, and the system works pretty well.
I think there's a checkbox for the external gyro in the setup page, but I'm not positive, I haven't used it. Last time I looked at that it could only be toggled in CLI mode.
You can't set the tail mode seperate from the others with the stock code. Could probably be modified, but it's not a priority. So at this point, if you're in stabilize, you get "heading-lock-like" gyro operation. And Acro mode really doesn't work for helis, so you're pretty much stuck with heading lock mode.
I have to imagine your problem with tail wagging has to do with your gains. And yes, they do work. It's kind of tricky because you have to tune the yaw rate PI and the yaw stabilize PI loops. I'd suggest zeroing out the stabilize PI terms, and work on the rate PI first. Like this is will work like a non-heading-lock gyro. So you get that stable, and then start working on the stabilize PI.
I'll try to get my values and post them here so you can see.
In my experience, without an external gyro, it works really well. Really well. I only have a small hickup at this point which is that if I input left yaw, it jumps to the right a few degrees before starting to yaw left. I'm trying to figure that out. I'm pretty sure it's something in the code.