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Typhoon H Pro does not hover and then bounces when landing without turning off props

Joined
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Smithfield NC
This is a tuff one. My Typhoon H Pro does not hover when it takes off but drifts and then bounces when landing without turning off props. I have tried the following:

1. Reflashed the firmware for both the aircraft and the ST16.
2. Re calibrated the compass everytime
3. Replaced the props just incase.
4. Recalibrated the accelerometer.

The drone and the ST16 connect and there is about 18 Sat.
Full batteries.

Any suggestions?
 
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First thing to check is the REAL output from your left stick. ("Hardware Monitor" is no good for this)

1.) Ensure drone is OFF.

2.) Do a quick double tap of the "VOLTS" display to bring up the final output graphic. See Attachment 35 (
ST16 Signal Processing Overview) of Way To Fix Drones project for details as needed.

3.) Ensure rabbit/turtle slider is FULL UP.

4.) Move the throttle stick up and down to verify range is 100% to 0%. (The 0% is more important for this discussion.)

5.) Now move rabbit/ turtle slider to FULL DOWN.

6.) Move the throttle stick up and down again. Verify the range is narrowed to about 80% to 20%.

Also note from this experiment that if the rabbit/turtle is not in FULL UP during landing, it is possible to have too much throttle in play (as much as 20%) to avoid bounce and to stop the props.
 
The drift on takeoff can be from trying to hover at too low a height. Take it up about 5 meters (16 feet). This gets it out of the turbulent air created by the propwash.
 
I agree with these suggestions. Also note that anytime landings are dicey, when the drone nears (6-8") the ground, press and hold down the red start/stop button.

Often, failed compass calibrations result in your drones behavior. Also, If it worked correctly in the past, try to think of anything that has changed since.

Take care in NC.
 
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First thing to check is the REAL output from your left stick. ("Hardware Monitor" is no good for this)

1.) Ensure drone is OFF.

2.) Do a quick double tap of the "VOLTS" display to bring up the final output graphic. See Attachment 35 (
ST16 Signal Processing Overview) of Way To Fix Drones project for details as needed.

3.) Ensure rabbit/turtle slider is FULL UP.

4.) Move the throttle stick up and down to verify range is 100% to 0%. (The 0% is more important for this discussion.)

5.) Now move rabbit/ turtle slider to FULL DOWN.

6.) Move the throttle stick up and down again. Verify the range is narrowed to about 80% to 20%.

Also note from this experiment that if the rabbit/turtle is not in FULL UP during landing, it is possible to have too much throttle in play (as much as 20%) to avoid bounce and to stop the props.
Great info, thanks. Is there a similar hidden menu in the SR24 that allow access to the REAL pot outputs?
 
Is there a similar hidden menu in the SR24 that allow access to the REAL pot outputs?
I don't know about the ST24. I don't have one to check.
I've looked for the menu on ST10, ST10+, ST12 and the ST16S version with H Plus firmware. I've never found the menu on any other than the ST16. It is possible it may be present on other firmware versions, of course, but not on the versions I've checked.

If you happen to have an ST24, you might want to check, and provide what you find to the forum.
 
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I don't know about the ST24. I don't have one to check.
I've looked for the menu on ST10, ST10+, ST12 and the ST16S version with H Plus firmware. I've never found the menu on any other than the ST16. It is possible it may be present on other firmware versions, of course, but not on the versions I've checked.

If you happen to have an ST24, you might want to check, and provide what you find to the forum.
Thanks for the prompt reply. I have a ST24 with a H920 but have not been able to find any hidden menus. Have not been able to get the H920 into compass or accelerometer calibration. Both operations require holding full left or right rudder then cycling the flight mode switch. Similar to some of the operations with the old Blade(Yuneec) 350QX. I suspect that there is not sufficient pot (J1) deviation output even with K2 set to max sensitivity. Any ideas?
 
First thing to check is the REAL output from your left stick. ("Hardware Monitor" is no good for this)

1.) Ensure drone is OFF.

2.) Do a quick double tap of the "VOLTS" display to bring up the final output graphic. See Attachment 35 (
ST16 Signal Processing Overview) of Way To Fix Drones project for details as needed.

3.) Ensure rabbit/turtle slider is FULL UP.

4.) Move the throttle stick up and down to verify range is 100% to 0%. (The 0% is more important for this discussion.)

5.) Now move rabbit/ turtle slider to FULL DOWN.

6.) Move the throttle stick up and down again. Verify the range is narrowed to about 80% to 20%.

Also note from this experiment that if the rabbit/turtle is not in FULL UP during landing, it is possible to have too much throttle in play (as much as 20%) to avoid bounce and to stop the props.
I did this process and it appears to work properly. Any other ideas would be appreciated.
 
no. I have not. My main issue is after I liftoff, the drone will not stay in one place. It fades and then sways so then I attempt to land it and it bounces. If I do get it down safely without flipping it, the motors do not turn off by themselves. I have to hold down the on-off switch for the drone on the ST16 to get it to shut down.

I did have a bad wifi card and had to replace it. The drone still has never flown correctly with after the Wifi card went bad. I had to buy a new ST16 because I could not find a wifi card by itself. I attempted to use the new ST16 but it would not fly correctly but it was the older ST16. SO I swapped out the wifi card from the new older ST16 and installed it in the original newer version ST16 but there was really no difference in the way the drone flys. Any suggestion? My warranty should be good until August 16 (1 year since purchase). If I can get Yuneec to respond about service. Is there anyone else who can work on the Yuneec H Pros on the east coast?
 
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My TH motors have never stopped just by holding the stick in the lower position. I always have to press the off button. I never questioned it, because that's how it is described in the TH Manual. (My H Plus DOES stop the motors on landing.) My TH doesn't bounce much on landing, but it is known as a difficult bird to land smoothly. I had to practice a LOT to get even reasonably decent landings.

Maybe it is one problem. Maybe it is two. Bouncing on landing is a common symptom of not having rabbit turtle in full rabbit during landing. If you could confirm whether or not it is your normal habit to land in full rabbit, it would help understand whether the landing problems are related to the flight problems, or if it is a different problem.

Regardless, the drifting and swaying are certainly an issue. Sounds a little like the "toilet bowl" effect, but I'm not sure. Does it seem to be moving in a circular pattern? @Steve Carr and a few others are much more familiar with that effect than I am.
 
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If the compass calibration appeared to go well, don't do it again. Every time you do a calibration there is a risk it will be a bad one.
Having said that, did you do it in an open grassy area away from concrete, buildings and underground power or pipes?

How many satellites are showing for the ST16?

You said it will not hover. Does it drift in a given direction? Can it be corrected with the right stick? Or does it react randomly as if there is no control?

Remove the camera before doing any more test flights. When you are ready to land, once you are around 12" above the ground, press and hold the red kill button until the H lands and shuts off the motors.
 
no. I have not. My main issue is after I liftoff, the drone will not stay in one place. It fades and then sways so then I attempt to land it and it bounces. If I do get it down safely without flipping it, the motors do not turn off by themselves. I have to hold down the on-off switch for the drone on the ST16 to get it to shut down.

I did have a bad wifi card and had to replace it. The drone still has never flown correctly with after the Wifi card went bad. I had to buy a new ST16 because I could not find a wifi card by itself. I attempted to use the new ST16 but it would not fly correctly but it was the older ST16. SO I swapped out the wifi card from the new older ST16 and installed it in the original newer version ST16 but there was really no difference in the way the drone flys. Any suggestion? My warranty should be good until August 16 (1 year since purchase). If I can get Yuneec to respond about service. Is there anyone else who can work on the Yuneec H Pros on the east coast?
I had a similar issue with a H920PLUS. It tried to tip over after landing and its hover was erratic. The problem turned out to be an uncalibrated accelerometer/ IMU. Since the H920Plus/ST16 and the Typhoon H480/ST16 share very similar flight controllers and flight software you might be experiencing the same issue.
If you can access the GUI with your H480 you can observe if you have a similar issue. See attached screenshots. The first shows the pitch indicating -10.5° while on a level surface. Thus the aircraft was trying to obtain level attitude after landing and level attitude while in hover. After accelerometer calibration(it took several) I obtained the results shown in the second screenshot. The acc cal can easily be done inside, just ensure a level surface with no metallic objects nearby. The H920Plus flys normally now.
FYI The motor RPM should decrease to ground idle after landing with the left stick in the full down position for a few seconds. This is approximately the same motor RPM observed after pressing the red motor start button before takeoff(both sticks neutral). This RPM does not normally create enough thrust to cause the craft to move unless there are wind gusts. Sorry I borrowed the ground idle term from turboprop terminology. 6A1E3905-AD24-4270-B234-48F194ED0270.jpeg410CD32A-E7DD-41C6-9B07-6C64EDC8FD55.jpeg
 
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This was very helpful. The drone still wobbles a little but now responds to my controls well enough for safe flight. So everything looks good but now my landing gear does not retract. One side makes a slight effort but the other side does not budge. If I get this fixed I think I will be back to full status. Suggestions.
 
So everything looks good but now my landing gear does not retract. One side makes a slight effort but the other side does not budge.
Remove the landing gear, slightly loosen the 5 screws that hold the retract module together and then test them with a 9 volt battery.

 
This was very helpful. The drone still wobbles a little but now responds to my controls well enough for safe flight. So everything looks good but now my landing gear does not retract. One side makes a slight effort but the other side does not budge. If I get this fixed I think I will be back to full status. Suggestions.
The side that makes a slight effort is probably fully functional. The system is built so that if either side is stuck, neither side will move. The good side will just "twitch" a couple degrees. You can verify this by removing the one that does not move at all, then turn the drone upside down and cycle the landing gear.

For the stuck side: (Note this assumes nothing is actually BROKEN.)
1.) Sometimes "bumping" the gear, and many cycles will get it to move without doing anything else.
2.) If "bumping" does not work, you can use a 9 volt battery to get the landing gear to free up. Only the two outside contacts do any thing. Apply 9volts briefly one way. If it moves, great. If it does not move, switch the voltage briefly the other way. Repeat a couple times if needed.
3.) If the 9 volt battery does not work, you will have to disassemble the actuator to get it freed up. Try the other items first, and let us know if you need help getting the actuator apart.
 
This was very helpful. The drone still wobbles a little but now responds to my controls well enough for safe flight. So everything looks good but now my landing gear does not retract. One side makes a slight effort but the other side does not budge. If I get this fixed I think I will be back to full status. Suggestions.
Great! Appears that you are getting some good advice on gear trouble shooting and repair. If you decide to test the Gear actuators by turning the aircraft over you will probably need to recalibrate the accelerometer. That is how my original uncalibrated accelerometer issue started with the H920Plus.
 
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I had same problems to this with my second H about 18 months ago, the failure to hold position and motors not idling on landing. I resorted to creating a new profile on the ST16. The bird behaved perfectly after that. I tried the old profile again and the problems reappeared. I deleted the old profile and that was that.

I get the impression that the code in the ST16 for the H sometimes doesn't close down properly and develops a glitch and then something on the bird doesn't work as it should. I have had it with both of my H Pro's and a new profile has fixed the problems each time.

I apologise if you have already tried this but thought it was worth mentioning.

Hope you get to the bottom of the problems.
 

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