Overshooting

[Topgunul]

Hello again,

i have a problem with my Autopilot. No matter what i change, Rollgain or sensitivity, the AP overshoot anytime, so the Plane fly like a snake. I use the SV 1000 two times with her GPS and a SV42 Servo for the roll servo. Thx

Torsten

 

[Dynon]

Hi Torsten. Have you been through the Autopilot In Flight Tuning Guide? If you haven't, that's absolutely the first place to start. Also, are you on the lastest version of SkyView software? We've made quite a few AP performance improvements over the past few years.

 

[Topgunul]

Yep, of course. I'm going min. 5 Times thought the inflightprocedure and the Wohle System is new, Means the Software is 10.1.

 

[Dynon]

Are you using simplified or expert mode? What kind of aircraft is it?

 

[Topgunul]

I´m using the Simplified mode for the Rollservo. The Airplane is a brand new BRM Bristell with retractable gear.

Any suggestions

 

[Dynon]

So first, ideally the autopilot should have be configured and tuned when the aircraft was manufacturered. So do check and see whether or not Bristell has settings that are known to work well. Beyond that, getting a diagnostics log from you would let us see what you're seeing and offer some advice. To do that, you need to have the autopilot fly (and behave as you're seeing) within an hour of when you take the log. Once you're back on the ground:

1. Insert a USB flash drive. You'll need at least 500mb of space.
2. SETUP MENU > SYSTEM SOFTWARE > EXPORT DYNON DIAGNOSTIC FILE > (right click) > (fill out the information requested) > EXPORT (button)
3. Diagnostic file will be saved to the USB flash drive.
4. Zip the file if you know how (this step isn't critical, but lowers the upload time to our servers)
4. Upload the file using http://www.dynonavionics.com/docs/upload.html (it's a BIG file - too big to email). In the message area, please put a link to this thread and a note that this is about an autopilot performance issue.

 

[Topgunul]

Thx, next fly i will Produce the file and send them to you.

 

[Topgunul]

Hello again, i think, i found the answer for the overshooting and trap in the next problem. The builder of the Aircraft use dynon skyviewstouch, 2 adahrs, anything from dynon included. The pitotprobe. Finally the windindicator hiev me all the Time a wrong Info. If im flying nearly without wind, the windindicator Shows 10 to 15 knots on the nose. If the wind Domes Cross, they Adel this and the Resultat was a wrong number. In my Suggestion, the Autopilot try to found the right Track, but he could.
How can i calibrate the Pitot and/or the windindicator to a real value? Any Suggestion. If the windindicator Shows nearly nothing, the Ap Works Fine.
The new Software is already installed, no changes at all.
The for help.

 

[dynonsupport]

The usual issue with incorrect wind data is that the compass is not calibrated or is not showing correct heading (something is causing magnetic interference to the compass. Can you confirm that the SkyView compass has been calibrated and the compass is indicating correctly?

Hello again, i think, i found the answer for the overshooting and trap in the next problem. The builder of the Aircraft use dynon skyviewstouch, 2 adahrs, anything from dynon included. The pitotprobe. Finally the windindicator hiev me all the Time a wrong Info. If im flying nearly without wind, the windindicator Shows 10 to 15 knots on the nose. If the wind Domes Cross, they Adel this and the Resultat was a wrong number. In my Suggestion, the Autopilot try to found the right Track, but he could.
How can i calibrate the Pitot and/or the windindicator to a real value? Any Suggestion. If the windindicator Shows nearly nothing, the Ap Works Fine.
The new Software is already installed, no changes at all.
The for help.

 

[Topgunul]

Hello,

i´ve sender you the diagnostic file yesterday with all infos.

Regards

 

[Topgunul]

Hello again, at the end, the AP Problem might the result of a broken Servo. But the difference between the TAS and the Groundspeed is still there. Any suggestion? Torsten

 

[Dynon]

Hi Torsten: We're corresponding with you over email, and since we're the same people here on the forum, we'll keep that thread going instead of duplicating that conversation here. But to summarize: because your IAS (and therefore TAS) is always high compared with GPS ground speed, no matter the wind at at sea level on a standardish day, and because SkyView agrees with another analog airspeed indication in the aircraft, we believe that this points towards pitot/static-based position error in the pitot/static system design which is causing the pitot/static pressure differential to be erroneously high. Thus, your IAS is incorrectly high. This is called pitot/static position error, and can be a challenge to nullify when designing the pitot/static system in an aircraft design, but it is something that needs to be addressed at the aircraft level. At this point we suggest that you engage the aircraft manufacturer and service network to help you troubleshoot this further.

 

[Topgunul]

Yep, sry for that. I will keep the conversation via mail.

Torsten