C23 gimbal went crazy after downloading logs

Frontier · Apr 24, 2022

Hello,

I have a Typhoon H+ aircraft running the latest Yuneec firmware (20190312).
The aircraft works fine since July 2018 when I bought it and the only issue I had was with the C23 having vibration issues, which Yuneec GmbH replaced with a new one under warranty.

Today I tried to download some log files from my Typhoon H Plus aircraft in order to upload them to AirData for inspection, using QGroundControl (from my Windows 10 PC) as shown in the following videos:

QGroundControl detected my H+ and I've downloaded the log files from the aircraft without issues. It took about 30 minutes to download about 1GB of log data, including the one from yesterday's flight.
After downloading, I closed QGroundControl and unplugged the USB cable from my computer. On powering the aircraft with my battery, the gimbal is now doing this:

The C23 connects to the ST16s fine (I can see the video feed on the display) but pitch/yaw control is impossible because of the gimbal erratic behaviour.
The drone is in excellent condition and was never crashed or anything like that. I also tried flashing the "gimbal fix" firmware (found elsewhere on this forum) but it did not help at all.

Is there any way I can fix the gimbal by calibrating it? I am pretty positive there is no hardware issue involved (i.e the gimbal does not do any strange beeps, it only does the normal initialization beep sound) and the issue is with the gimbal PID or encoder settings being messed up after downloading the logs from QGroundControl.

Many thanks in advance.

Vaklin · Apr 24, 2022

Misplaced or defective magnetic ring.

If the camera is still under warranty, just contact the workshop.

DoomMeister · Apr 24, 2022

Did you do anything else in QGC besides access the ulog files on the aircraft?

Does the gimbal act like this with just the aircraft and camera powered up? Or does this behavior start after they bind with the ST16S?

I would consider unbinding the aircraft and camera in the ST16S controller settings, then rebinding both to see if it makes any difference in gimbal behavior.

Frontier · Apr 24, 2022

@Vaklin: How is that possible? The gimbal was working fine on 23th April when I did a flight and the drone was not crashed or mistreated in any way. The camera was replaced by Yuneec GmbH under warranty on August 2020, so the warranty is now over.
The only thing I did was download the logs from the H Plus using QGroundControl.

@DoomMeister: No, I did not do anything else with QGroundControl (I am familiar with the software from my ArduCopter drones) besides downloading the logs, not even browsing the menus while the aircraft was connected.
The gimbal does this "dance" no matter if it is connected to the ST16s or not. When connected, I can see the picture on the ST16s but it is impossible to control the gimbal due to the shaking.
I already did the following things and nothing helped: 1) unbounding/rebinding the C23 to ST16s (both camera and drone), 2) flashed the "gimbal fix" firmware found in this post

DoomMeister · Apr 24, 2022

Frontier said:
@Vaklin: How is that possible? The gimbal was working fine on 23th April when I did a flight and the drone was not crashed or mistreated in any way. The camera was replaced by Yuneec GmbH under warranty on August 2020, so the warranty is now over.
The only thing I did was download the logs from the H Plus using QGroundControl.

@DoomMeister: No, I did not do anything else with QGroundControl (I am familiar with the software from my ArduCopter drones) besides downloading the logs, not even browsing the menus while the aircraft was connected.
The gimbal does this "dance" no matter if it is connected to the ST16s or not. When connected, I can see the picture on the ST16s but it is impossible to control the gimbal due to the shaking.
I already did the following things and nothing helped: 1) unbounding/rebinding the C23 to ST16s (both camera and drone), 2) flashed the "gimbal fix" firmware found in this post

Thanks for the update!

The thinking cap is in place and warming up.

Vaklin · Apr 25, 2022

Frontier said:
How is that possible? The gimbal was working fine on 23rd April when I did a flight and the drone was not crashed or mistreated in any way.

The magnets are suffered from degradation over time. This is the manufacturer's fault. Not related to the log download at all. There was a topic about a CGO3+ with a picture of a blown magnet. Your situation looks to be similar.

Frontier · Apr 25, 2022

Vaklin said:
The magnets are suffered from degradation over time. This is the manufacturer's fault. Not related to the log download at all. There was a topic about a CGO3+ with a picture of a blown magnet. Your situation looks to be similar.

If this is the case (i.e broken magnets), then this C23 is completely trash.
It is a new camera replaced under warranty on August 2022 with only 10 flights since then (due to multiple Covid-19 lockdowns in Greece, I've rarely had the chance to fly)

Vaklin · Apr 25, 2022

All sintered magnets are with a limited lifetime. The camera itself as a product is OK.

In your particular case, the magnet can be displaced only. In any case, this is repairable.

If you haven't an electronic repair skill, don't try to open it.

Frontier · Apr 25, 2022

Vaklin said:
All sintered magnets are with a limited lifetime. The camera itself as a product is OK.

In your particular case, the magnet can be displaced only. In any case, this is repairable.

If you haven't an electronic repair skill, don't try to open it.

I can solder (have a couple DIY racer quads) and have good knowledge of SToRM32 and BGC gimbals (although never had to deal with their magnets).
I will probably contact Yuneec GmbH to issue an out of warranty RMA as I do not see anything related to C23 gimbal magnets on WTFD documentation.

Vaklin · Apr 25, 2022

The camera should be calibrated after visual magnets check. This can be done in the official workshop only. Just a replacement with a new magnet will give the same result, that you are seeing now.

So, no reason to give half solution in the document.

Frontier · Apr 25, 2022

Vaklin said:
The camera should be calibrated after visual magnets check. This can be done in the official workshop only. Just a replacement with a new magnet will give the same result, that you are seeing now.

So, no reason to give half solution in the document.

After your advice about the misplaced magnet (and Yuneec Europe not responding to my e-mails for service), I've decided to (carefully) open up my C23 in order to check if any of the pitch, roll and yaw magnets are degraded. The WTFD documents are very helpful.
Seems that my "new" camera was not actually new but a repaired one; 5 out of 6 top wires were patched, the two small screws on the top of the camera mainboard cover were missing but he did marked with arrows the way the motors should be mounted

He also used some black liquid tape to secure the cable clip (the small black one) each encoder has.

So far I have checked the pitch and roll magnets and they are clean, no magnetic dust or any sign of tear.
I cannot check the yaw magnet as I have to remove its encoder board first and this can only be done (I guess) after removing the camera from the U mount.
But everything looks clean, no signs of degraded magnets like the CG03+ ones on WTFD documents.

I do suspect that the problem is with the yaw axis/motor but this is as far as I can go.

Anyone can recommend a good Yuneec authorized service centre in Europe that can fix the gimbal?
My trust on Yuneec GmbH is gone after finding out that they sent me a C23 in a worse condition than mine (mine at least had all its screws intact

) that lasted only 10 flights.

Vaklin · Apr 25, 2022

Don't touch the yaw magnet.
Mark carefully pitch and roll magnets with some marker. Rotate very slightly the roll magnet in one direction. Test the camera. If the situation is worse, try another direction over the mark. If you don't get better results, place the magnet in the marked position and try the same with the pitch magnet.

Magnets should be rotated with some pinset. Better to be not a magnetic one.

WTFDproject · Apr 25, 2022

Frontier said:
I cannot check the yaw magnet as I have to remove its encoder board first and this can only be done (I guess) after removing the camera from the U mount.

The Yaw magnet is visible in your second image. You can rotate the motor to inspect all the way around the magnet without further disassembly. Mark a spot on the edge so you can see the movement.

PGL Drone techniek · Apr 25, 2022

I repaired a lot of Yuneec camera's so please be very careful with replacing the magnet rings.

Frontier · Apr 25, 2022

PGL Drone techniek said:
I repaired a lot of Yuneec camera's so please be very careful with replacing the magnet rings.

Are you located in Europe?

Frontier · Apr 25, 2022

WTFDproject said:
The Yaw magnet is visible in your second image. You can rotate the motor to inspect all the way around the magnet without further disassembly. Mark a spot on the edge so you can see the movement.
View attachment 27949

I've marked the edge of the magnet and the spot moves when I rotate the yaw axis motor together with the mounting base.
I have reassembled the gimbal and to do the magnet mark I just removed the cover on the base of the yaw axis motor.
I do not see any problems with cables, both the wires and the ribbon ones and the gimbal does not make any error beeps on startup (besides the usual startup sound).

Vaklin · Apr 25, 2022

Every magnet has a position that is written in the MCU. There are no broken wires. We didn't discuss any wires. Don't move the yaw magnet. The camera will start spinning. The problem is with the position of the pitch or the roll magnet.

Frontier · Apr 25, 2022

Vaklin said:
Every magnet has a position that is written in the MCU. There are no broken wires. We didn't discuss any wires. Don't move the yaw magnet. The camera will start spinning. The problem is with the position of the pitch or the roll magnet.

I will try that tomorrow and report back. Hope you are right.
Thank you for your help.

PGL Drone techniek · Apr 26, 2022

Frontier said:
Are you located in Europe?

Yes in Holland

Frontier · Apr 26, 2022

I cannot move the roll magnet and it is not possible to access the pitch magnet without making cosmetic damage to the case, therefore I stop here.
I will try to find a service centre but I still have a feeling (and because the camera has no encoder errors/beeps) that all it needs is re-calibration.