accelerometer has to be recalibrated each flight

[Hunter]

I tried compass calibrate but that did not stop it.

Lately if I do not re calibrate the accelerometer, it toilet bowls on me. Difficult to land with out prop damage.

I just flew several different locations in a 40 acre field and each time I got lucky and landed without damage. Lots of stick movement in agility got it down and I hit kill. Quit while I was ahead...........

Could this mean the accelerometer itself is going bad?

Sun flares, space aliens, government drone guns??

 

[Steve Carr]

Have you installed the latest firmware? If not that may help.

 

[Tuna]

Basically your drone should not be behaving that way - and the vast majority of Typhoons are fine, so you need to identify the problem *before you have an accident*.

Remember rule one - if your drone is not behaving the way you expect, Stop flying. Do not keep trying to fly it as an uncontrollable drone is extremely dangerous.

As for steps to diagnose and fix your problem:

1. Check that your controller is working properly. On the ST-16 go to System Settings -> Hardware Monitor and check that all of the sticks and buttons behave correctly. In particular, check that J1, J2, J3, J4 are at zero when you're not touching the sticks, and go all the way to +/- 100 when pushed fully left / right / up / down.

2. Make sure your software is up to date. The current versions of the ST-16 software are v30.01.b30 (check in the System Settings -> About controller window). The aircraft should have Auto pilot 1.35 which has just been released. If they're not up to date, find the YouTube video released by Yuneec that explains how to do an upgrade.

3. Check that the IMU is stable. Take your Typhoon indoors, put it on a level base away from any major interference or metal then start it up. Run the Yuneec Windows GUI and plug the drone in. On the Sensor Information tab you should see the Accelerometer and Gyroscope readings. For the Accelorometer X, Y, Z on my machine are about 2, -10, -980. Gyroscope are around 2, 2, 2. The small numbers mean that the H thinks it's sitting pretty much still - which is what you want. The Big Z value for the accelerometer is the force of gravity, perfect!

4. Take your Typhoon out, put it on a level surface and switch it on by pressing the power button without moving it at all. Let it sit still whilst it's initialising or the accelerometer will get confused. Let the controller connect and then check the number of satellites - you should get at least 10 on both the controller and drone. Let the Typhoon sit for 15 minutes to ensure the GPS is completely up to date (this is unlikely to be a problem, but we're eliminating all possibilities here). Now go for a flight.

5. When landing, make sure you are in Angle mode, or that the machine is properly outside the safe circle (26 feet) - make sure you understand just how far that is. Pull down cleanly and make sure you land on a relatively flat surface. As soon as the machine is down, keep your throttle stick held down and at the same time hold the red button until the props stop. Do not approach the craft whilst you're doing this. Normally you should hear the props slow down when it lands, but that does not mean it's safe. Wait until you have stopped the props before letting go of the throttle or walking towards it. Note that natural instincts tend to make people do both of these unconsciously, so pay attention when landing.

If the machine gets into an uncontrollable spin when there are no inputs on the controls and does not respond to normal inputs, land immediately, do not attempt to fly again. Contact Yuneec and they should be able to take it in for a fix.

If it drifts slightly (1 or 2 feet), that's perfectly normal. GPS is not 100% accurate, so some movement is to be expected.

If you want to help us, please let us know when you bought the Typhoon, the current firmware versions and how many flights you've had to date.

 

[Airtography]

Great advice from Tuna on this one. The only thing not mentioned is to clear the ST16 application data, then recalibrate the St16 completely (all controls and sticks as described above). Also, make sure you're on a perfectly level surface when calibrating accellerometer.

 

[Dr Delta]

Great advice from Tuna on this one. Also, make sure you're on a perfectly level surface when calibrating accellerometer.

or carefully hovering in no-wind conditions (Manual 1.2, page 22, video)

See VR-Pilot's post @manual topic.

 

[Andraika]

try to remove batery from ST16 and leave station for a few mins with pos "on", helped for me, when I had weird issues with gimbal calibration. Not sure, but I think, that there can remain errors in tablets RAM or something..

 

[PatR]

Two things come to mind as I read the initial post. One has a problem within system hardware. The other has the user doing something wrong during system start up. Odds are high user error is the culprit.

If the aircraft is moved after start up, before system self checks are complete, you can calibrate until the moon turns blue. I mention this because many people are in a hurry and try to shave time off the start up process by turning on the H before they raise the arms or put it on the ground. Some power up the H and then carry it to the launch point. Make the H flight ready, find the launch point, set it down, power it up, and leave it alone until you arm the motors.

The fault described is almost unheard of with the H, prompting me to suggest personal self checks before looking any harder at the machine.

Regarding the "in flight" calibration video. I must ask if that was provided by Yuneec corporate? I ask because the only systems that allow this type if calibration are APM based and require the system to self calibrate through a series pitch and roll oscillations that an H simply does not perform. If the video was not released by Yuneec corporate, use this method at your own risk.

 

[Dr Delta]

Regarding the "in flight" calibration video. I must ask if that was provided by Yuneec corporate? I ask because the only systems that allow this type if calibration are APM based and require the system to self calibrate through a series pitch and roll oscillations that an H simply does not perform. If the video was not released by Yuneec corporate, use this method at your own risk.

Hi Pat,

This method is in the official new YUNEEC manual (V1.2), the guy on the movie just executed what is in there.

Tried it, but a little to much wind here, so calibration not completed. Switching GPS off made the bird dance a lot and it drifted off to fast for me.



Cheers!

 

[AZSteveB]

Yes, I've had more issues since upgrading to the latest released software than ever before. I've wrecked 2 props on each of two landings that went bad. Both instances were angle mode switched from RTH mode to manual landing and taking control, then bringing it down gracefully for the last 10 feet it hovers once close to the ground starts weird ocillations until it tips over and wipes out two props in the rear. Did NOT have the issue prior to the latest updates.

 

[ArnhemAnt]

If the aircraft is moved after start up, before system self checks are complete, you can calibrate until the moon turns blue. I mention this because many people are in a hurry and try to shave time off the start up process by turning on the H before they raise the arms or put it on the ground. Some power up the H and then carry it to the launch point. Make the H flight ready, find the launch point, set it down, power it up, and leave it alone until you arm the motors.

I could not agree more with the above. In one of my first flights, I powered on the H, then flicked the arms up and installed the props as it was initializing. I then found that the characteristics once in the air, trying to hover, were not consistent. Now, I make a point of having everything ready (arms up, props on, etc) prior to powering on the H, and, once it is on, I do not pick it up or move it around. Ever since that time, all my flights have been without a single concern.

 

[PatR]

When used with APM, the in flight process is for establishing gains/PID's, something we don't have access to with the H. Most accelerometers I'm aware of need to be calibrated at rest. Must be something new.

 

[Rayray]

Hi Pat,

This method is in the official new YUNEEC manual (V1.2), the guy on the movie just executed what is in there.

Tried it, but a little to much wind here, so calibration not completed. Switching GPS off made the bird dance a lot and it drifted off to fast for me.



Cheers!

I cannot speak to Typhoon H Europe, and I have seen several videos regarding what you say. That manual is not the USA manual and that particular section is incoherent.

One video claiming to show an in-flight Accelerometer shows no such thing. Another, in German, refers to two methods.

What I can say with confidence is for USA members to perform this calibration indoors on a level surface. No flying necessary.

Any member is welcome to put forth their operational methods and their beliefs, but please do not go against numerous videos showing correct methods of Calibrations for many of us.

@PatR has put this into context very well.

 

[ChadCloses]

Just curious how much flight time will you lose if you wait 15 min every time you put in a battery. I'll try anything at this point.

 

[Eagle's Eye Video]

Just curious how much flight time will you lose if you wait 15 min every time you put in a battery. I'll try anything at this point.

Almost none, since the vast majority of power is used by the motors when engaged, and the camera...
I'd be surprised if the actual flight time is reduced by more than 90 seconds - 2 minutes max.

At some point, you will have one of your batteries start to go and show a significantly reduced flight time.
When that happens, get a new battery and earmark the one with reduced flight time to be your
calibrations/firmware updates/camera settings/sitting to get GPS lock battery...

 

[PatR]

I have an absolutely well trashed battery sold to me as good by a previous crasher that serves that purpose very well. On a good day it will last about 15 minutes at system standby. I'd be happy to make an indefinite loan of it Does work good for updates though...

Side note moral; if you ever get sold a 4s battery that arrives with a voltage reading of 12.8v you got had.

 

[Steve Carr]

Just curious how much flight time will you lose if you wait 15 min every time you put in a battery. I'll try anything at this point.

Why would you need to wait 15 min on every flight?

 

[Dr Delta]

I cannot speak to Typhoon H Europe, and I have seen several videos regarding what you say. That manual is not the USA manual and that particular section is incoherent.

One video claiming to show an in-flight Accelerometer shows no such thing. Another, in German, refers to two methods.

What I can say with confidence is for USA members to perform this calibration indoors on a level surface. No flying necessary.

Any member is welcome to put forth their operational methods and their beliefs, but please do not go against numerous videos showing correct methods of Calibrations for many of us.

@PatR has put this into context very well.

I was not aware of a different H being built for USA market or different instructions needed at the USA side of the world.
I am used to any manual on the H being incoherent (and incomplete).
I have no belief at all, I am just curious and read a lot. Maybe that's why I never ever had any issue with my H (or is it pure luck?)
The German video (the only one on this subject I viewed) also states no flying is necessary though it might be useful.
I do not go against anything at all, I just shared information (in a cautious way, referring to official Yuneec sources).



Cheers!

 

[Hunter]

Thanks Tuna for that very thorough reply.

I have been flying this model since they came out, almost a year and go thru all the careful step by step procedures when flying.

I did one firmware update shortly after I got it and about the only thing I noticed was faster camera connection.

Since that time I have flown 3 or more times a week for 3 batteries worth each day.

I did have a recent crash lately and suspect that might have confused the acellorometer.
I can do a calibrate each time and it flys as always.

I have held off on several of the updates because of negative results from a lot of people. Don't know if all of them were operator error.
I was waiting for the ahha moment when an update was successful.

If it flew for that long without issue and only started after the crash I have a hard time believing a newer firmware is going to "fix" something that may be damaged.

I will take all this into consideration and do some more research but before I update I think I should resolve this instead of adding to the equation.

I don't even know if it can be replaced if it is on the motherboard, if that is the problem.

Thanks again for all the replies, I will continue to work on this.

 

[Hunter]

Two things come to mind as I read the initial post. One has a problem within system hardware. The other has the user doing something wrong during system start up. Odds are high user error is the culprit.

If the aircraft is moved after start up, before system self checks are complete, you can calibrate until the moon turns blue. I mention this because many people are in a hurry and try to shave time off the start up process by turning on the H before they raise the arms or put it on the ground. Some power up the H and then carry it to the launch point. Make the H flight ready, find the launch point, set it down, power it up, and leave it alone until you arm the motors.

The fault described is almost unheard of with the H, prompting me to suggest personal self checks before looking any harder at the machine.

Regarding the "in flight" calibration video. I must ask if that was provided by Yuneec corporate? I ask because the only systems that allow this type if calibration are APM based and require the system to self calibrate through a series pitch and roll oscillations that an H simply does not perform. If the video was not released by Yuneec corporate, use this method at your own risk.

No, sorry to disappoint but I did not do any of the improper things you stated.
You have heard of it now!

 

[Hunter]

After multiple repairs to the GUI I finally got connected. My readings appear very similiar to Tuna's on both of my H's.
Both run V1.15 but only unit 1 has the affliction.

I think I will try Yuneec for their thoughts on this if I can get thru tomorrow.