[bmw111]

I know, another "noob PID issue" right? Well, not in this case. This is the fifth quad I've built -- three with MWii boards, a RMRC HellBender 122 with CC3D/LP (which flies locked in on rails), and now this X-Quad ZMR250. Until this quad I've been able to get them all flying reasonably well, with no oscillations, until this X-ZMR with CC3D/LP. I had such an easy time tuning the HB 122 with LP, and it flies wonderfully, I thought I'd try the same CC3D/LP combo on this new one. Well, just look at the videos linked below and see how this one is the complete opposite. I've never had such a difficult time finding a good "baseline" to tune from.

In the video I've linked the first part shows the "default" LP X-Quad PID settings. The second part shows the PIDs tweaked to just get it barely flyable. However, you can see I had to set the "P" VERY low, and if I go any lower, the quad becomes unflyable, like a drunk on roller skates. Doesn't matter if I increase or decrease the "D," same thing. The only way I can get it to respond better to my inputs is to increase the "P," which brings back the terrible bumpiness/oscillations from the first video. Believe it or not, the second part of the video is the "best" I've been able to get it to fly. In between those two parts, I installed three different "Profiles" from the LP GCS, tweaked them all multiple times, and got the same terrible results.

https://www.youtube.com/watch?v=ZFv1MkgWtPM&feature=youtu.be

When I lower the P super low, the "on throttle" oscillations go away, but the "bumpiness" is still there, and it flies way too loose, almost uncontrollable. Am I missing anything obvious? I'm frustrated because I was able to get the HB 122 w/LP tuned almost perfectly in a very short time, but with this quad no matter what I do, the same terrible performance results. I know others are flying similar setups with 6" props and even on 4S so it's not something inherent to this configuration.

Any ideas? Anyone care to share their profile/settings for a similar quad?

Configuration:
"Toby" 3D printed ZMR250 X-frame (ABS, super strong and stiff)
RotorGeeks 12A ESC, BLHeli, no OneShot
Cobra 2208/2000 motors
6x4.5" DAL bullnose props
3S 1600
CC3D RTFQuads board

Default LP X-Quad PIDS:
         Roll           Pitch           Yaw
P       0.00300     0.00300      0.00620
I        0.00650     0.00650      0.010000
D       0.000033   0.000033     0.000050

Modified PIDS:
        Roll           Pitch           Yaw
P       0.00165    0.00165     0.00494
I        0.00264     0.00264      0.00790
D       0.000013   0.000031     0.000040

[f5soh]

First i think you did a typo with Dterm / Pitch. 13 / 31 ?

Indeed defaults Pid are way too high for a mini mini.

Please post your config file. File > Export UAV setings

[bmw111]

Hi, UAV file attached. Thanks for any advice you can give.

[bmw111]

Honestly, at this point I'm just looking for a good starting point for this multi. Seems every profile I've tried has been a disaster, and even the default settings haven't worked.

[hwh]

I'm not good with PID tuning but I wanted to pop in and tell you that the person who's been helping you (f5soh) is very good at helping people get going.  However, he's in France and probably not online now.  This is the quietest time for the forum, both Europe and the US have mostly signed off.   The Europeans usually start appearing again in about 4 or 5 hours.

[bmw111]

Thanks, hwh. I understand. I'm in the U.S., East Coast.

[hwh]

So am I, central NJ.

-Hank

[jbarchuk]

There's also the Asian/AU/NZ region, which with NA and EU covers all three 'shifts.'

[f5soh]

About your config file:

- You are using PPM-NoOneshot (pin3), better if you set to PPM_Pin8+OneShot. You only need to move PPM wire to pin8.
   If your Esc are with BLHeli firmware, use Oneshot !



- Currently you set output to PWM and 50Hz, so very slow refresh and stabilization is not reactive.

Reload file attached

[bmw111]

OK, when I did the vehicle wizard the first time I chose PPM_Pin8+OneShot. The ESCs were having arming issues -- only one would arm/spin, then a minute later another one would arm/spin, then 30 seconds later the last two would arm. Random arming sequence every time I powered up. These RotorGeek ESCs are supposed to "autodetect" whether you are using OneShot or not, so I thought I should try PPM_NoOneShot. After I switched to PPM_NoOneShot the ESC arming issues went away. No problems arming/spinning. That is the reason I am using PPM_NoOneShot.

The ESCs are V4:
http://rotorgeeks.com/index.php?route=product/product&product_id=95

I don't know why output is set to PWM/50Hz, I thought the wizard set that based on choosing "PPM..."? Or do the vehicle profiles make changes to the output? I admit I did not check those settings after loading different profiles.

Should I run the wizard again?

[Chilledoutuk]

Quick fix would be to set the PWM rate to 490hz I run that on my simonk escs and that quad handles pretty good.

You might need to connect to the esc's using blheli suit and check what version you are running and whether can upgrade the firmware which might fix your oneshot issue.

[f5soh]

Like Chilledoutuk says, there is no issue with Oneshot BLHeli firmware.
Update Esc firmware, load the config file i put in my last message.

Set input to PPM_pin8 and you can at least use the PWMSyncr as OneShot replacement.

PPM_pin8 is compatible with all output modes: PWM, PWMSyncr, OneShot
PPM_pin1 is only compatible with PWM output.

[bmw111]

Like Chilledoutuk says, there is no issue with Oneshot BLHeli firmware.
Update Esc firmware, load the config file i put in my last message.

Set input to PPM_pin8 and you can at least use the PWMSyncr as OneShot replacement.

PPM_pin8 is compatible with all output modes: PWM, PWMSyncr, OneShot
PPM_pin1 is only compatible with PWM output.

OK, thanks. Will do and report back.

[bmw111]

OK, flashed latest BLHeli firmware (14.4) to ESCs, uploaded revised UAV file, switched to pin 8, and now the ESCs all "arm" (series of beeps) at the same time, normal behavior, except this time the motors won't spin at all -- the throttle doesn't do anything. However, in the "RC Input" tab, all controls operate as they should, including the throttle.

I'm using a DragonLink Copter RX PPM -- which I used to fly in the video you saw. I check the RX firmware and setup and it is setup correctly for PPM output.

EDIT: I did the Tx wizard, same problem. All RC controls are operating correctly according to the RC Input tab, but will not operate the throttle.

Just for a trial I left pin 8 attached, switched OneShot125 to PWM w/490Hz -- still the throttle will not spin the motors. I did the Tx wizard again, with these settings, and still the same problem.

And, to be thorough, I also tried the PWMSync settings -- same exact problem, but now the ESCs all arm at different times, like the original "bad" ESC behavior.

EDIT II: Success!
I put all settings back to f5soh suggestions, ran the Vehicle Setup Wizard again, and everything now works as it should. ESCs arm "on time," throttle behavior normal, and I am not getting the terrible oscillations I was getting -- at least in the "hold the quad tightly and throttle up" test. Hopefully it will stop raining here and I can test it in the field. Thanks to all for the help, and for the profile, fsoh.

To recap, I flashed the latest BLHeli firmware, ran both the Vehicle Setup Wizard and Transmitter Wizard, and that solved it.

[dereelmatts]

Sorry im a noob, how do you update/change the esc software?