Drone Typhoon H Aquiring

[WTFDproject]

I am resuming this discussion...

The surprise is that it did finally acquire. That suggests the problem may be different from the common failure of the flight control board. However, that problem is so often the cause, it should be eliminated first. Have you connected to the GUI and compared your results to the indicators provided by @h-elsner in no gps lock on typhoon H

 

[Pier2162]

Have you connected to the GUI and compared your results to the indicators provided by @h-elsner in no gps lock on typhoon H

I'll do tomorrow

 

[h-elsner]

The GPS backup battery is a rechargeable Lithium battery MS621FE, 3V. It is overdischarge-able but charging takes a long time.

But from the description I think the cause of the problem is not the backup battery (backup is only to keep RTC living and hold data in order to get faster GPS lock). Switching off GPS and motors won't start points to IMU problem. Degradation of IMU is a gradual process. It is possible that IMU bias if get warm enough can move to acceptable values to finish pre-flight test. I recomment doing an accelerometer calibration in this case, possibly multiple times to get bias back to normal values.

br HE

 

[Pier2162]

Thanks Helmut for your input.
I think you gave me the right way to solve the problem: connecting to the GUI, I've seen that the yaw value was decreasing very slowly, so I did a couple of accelerometer calibrations and now the yaw value seem to be stable.
So, in your opinion, does this be a possible issue on the imu?
Attached a screenshot of the Gui.
In the afternoon, when temperature will rise a little (now - 4 degrees Celsius) I'll try a new flight.

 

[DoomMeister]

I saw this post What is the Coldest Temperature you can fly a Phantom 3 Standard? in PhantomPilots forum a few days ago.

I wonder if the temperature you calibrate at can make a difference in cold weather like was suggested.

 

[Pier2162]

I saw this post What is the Coldest Temperature you can fly a Phantom 3 Standard? in PhantomPilots forum a few days ago.

I wonder if the temperature you calibrate at can make a difference in cold weather like was suggested.

Interesting, but I don't think it's the case, yesterday the out temperature was around 46~48 °F (8~9 °C) and the drone was at higher surely, 'cause coming from in house temperature.
Anyway... I just made another flight, the acquisition of the satellites was almost immediate and I did not encounter the malfunction of yesterday.
Hopefully it was just a need for accelerometer calibration.

The GPS backup battery is a rechargeable Lithium battery MS621FE, 3V. It is overdischarge-able but charging takes a long time.

If I would to recharge it, is it enough to insert the drone battery in its bay or do I also have to turn on the drone?

In your opinion, how long would it take to charge it completely?

 

[Vaklin]

Turned on. No idea how long. There is a 1K resistor in the series of the charging line to limit the current. But for sure the battery is OK. Just do an IMU calibration after a long stay.

 

[h-elsner]

Moving Yaw is one of typically symptoms for IMU problem.
Yaw rotation: https://1drv.ms/v/s!AtiK_DeOGL5sir0A2Rbx7y7Zq4-SHg?e=UTRLzF

The others are:
- Motors will also not start when GPS was switched off. This unusual behavior can be used as quick test to identify the fault.
- Altitude on ST16 shows some meters below zero and did not initialize. The pressure sensor’s height estimate is OK, near zero at this time.
- Accelerometer Z-axis has a value far below 1000mG. This is wrong because we have 1G on earth. This indicates the root cause of the problem: ACCEL_ZOUT of MPU < 1000mG.

br HE

 

[Pier2162]

I saw your other post linked by DoomMeister, in my case the yaw variation was not so fast like in the video, and I did not had the other symptoms you're mentioning.
I had only motors not spinning.
Altitude was OK, Z axis too.
After calibration, yaw value was stopped.
I did few flights after calibration without issues.

 

[h-elsner]

Sounds good. Flying, calibrating the accelerometer and storing horizontally is the best prevention against IMU bias running out of boundaries (imho).

 

[Pier2162]

Sounds good. Flying, calibrating the accelerometer and storing horizontally is the best prevention against IMU bias running out of boundaries (imho).

I always have stored my drones horizontally, and fly them every 2 months.

 

[Yuneec Skins]

Typhoon H "Stuck" on "Acquiring" GPS Lock - won't Arm for Take-Off...

Test your Drone with the Typhoon H GUI & Check to see if "Yaw" slowly Rotates while Drone is Stationary;

If "Yaw" is slowly Rotating while the Drone is stationary, the Flight Control (FC) Module is Defective.
Download Typhoon H GUI Software (Note: You must Turn "Off" your Antivirus Program Before Downloading & Installing the Typhoon H GUI Software - Use the OEM USB Cable to Connect the Typhoon H to your Computer or Laptop)

 

[Pier2162]

Thanks John.
Yaw doesn't have deviation.
Can anyone tell me what is the minimum number of satellites that TYPHOON and ST16 must acquire to have the "GPS ready"?

 

[Yuneec Skins]

Thanks John.
Yaw doesn't have deviation.
Can anyone tell me what is the minimum number of satellites that TYPHOON and ST16 must acquire to have the "GPS ready"?

The "Yaw" Rotation is just 1 indicator of a Faulty Flight Controller. If your "Stuck" on "Acquiring" GPS, I'm 99% sure it's your Flight Control (FC) Module that is the problem... If you buy 1 from Yuneec Skins and it doesn't solve the issue you can Return it, and Exchange it for the Part you need, or get a Refund of the Purchase Price

 

[Pier2162]

At the moment the drone seems do not have any issue, and flies normally.
GPS acquiring is correct, doesn't stuck, I get the "ready" after 20~30 seconds from start up, so, it works perfectly after accelerometers calibration.
I'll see in the next flights. Thanks

 

[Pier2162]

However, I'm always doubtful about what could have caused that condition...

 

[Yuneec Skins]

However, I'm always doubtful about what could have caused that condition...

I haven't seen a case where the Typhoon H Flight Control (FC) Module Failed during Flight Causing a Crash...
It's always been the case that the Drone won't obtain a GPS Lock, and is "Stuck" on "Acquiring" when the FC Module has Failed... Usually when the Drone was stored for more than a few weeks...
I doubt it will Fail during Flight...

 

[Vaklin]

One of the sources of this condition is the barometric pressure sensor. It can stop working at any time. When the copter is airborne too.

 

[Pier2162]

But for sure the battery is OK.

I, on the other hand, have doubts, because yesterday and even today I made a few flights and I noticed that at the first battery of the day the GPS takes a long time to acquire the lock, while with the following ones the GPS locks on almost immediately.

 

[Vaklin]

You can measure the voltage if you want.