My own UAVP: Part 8 - Software Bug?
Created by Amir on the 20. May 2007 at 16:57 in UAVP | Permalink

Today we continued our testflights. We still want to eliminate the periodic movement we have on the gier acis. We tested a lot of different parameters, bigger and smaller integregrals as well as no dampening by setting the differential values to zero.

It all seemed to no avail. We had that periodic movement all the time exept when we started perfectly so that no gier correction seems neccessary. As soon as some movements on the gier axis starts the periodic movement never ends again.

Strangly my brother does not experience this problem through he experiences another problem which I have as well. Suddenly without cause the whole UAVP flips or extremelt starts correcting in one of the nick or roll axis. This most often results in a crash or even a broken propeller.

We taped my tests again. You will see our testflights with the 3.12 software using different integrals and no differential. Later on we raised the differential parameter as well in the hope to dampen the periodic movement. In the last scene I rolled back to the 3.11 software to see if the periodic movement exist there as well but as you can see on the movie, it does not exist in the 3.11 software which let's us guess that the problem has something to do with the compass support which 3.12 introduces.

Interesting is that my brother is able to fly 3.12 without a periodic movement on gier, but on the other hand, his gier seems not to be very stable and we saw turn arounds of 180 degrees!

This where my testflights:

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Later on we powered up my brother's UAVP and did further tests. It seems that the perodic movement of the gier axis can be eliminated by setting the integral value of the gear closed-loop control to zero.

More tests showed that even a value of one in the gier integral will result in small periodic movements.

Following we show yoy the later testflights my brother did. They were quite successful as you can see! Setting the gier integral to zero seems like a very good idea at the moment!

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I think this movie shows quite good that the new setting with the gier integral value of zero is at least a good fix for the moment to counter the priodic movement problem.

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