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Strange yaw bug or is it me ?
Posted: 17 Jun 2008 22:15
by Taurim
I've found a strange behaviour.
If i keep the left stick (mode 2) to the minimum an put it to the left, the heli turns counter clockwise. Perfect.
Now, if I move the stick to the right, the heli starts to slide rapidly to its left !
If I give a little bit more gaz (just over the minimum), the heli correctly turns clockwise when I put the stick to the right.
PPM.xml :
Code: Select all
<?xml version="1.0" encoding="UTF-8"?>
<project>
<Pitch>z</Pitch>
<InvertPitch>true</InvertPitch>
<Roll>x</Roll>
<InvertRoll>false</InvertRoll>
<Nick>y</Nick>
<InvertNick>true</InvertNick>
<Yaw>ry</Yaw>
<InvertYaw>true</InvertYaw>
<ServoPlusx>3.3449368</ServoPlusx>
<ServoMinusx>2.3093243</ServoMinusx>
<Offsetx>0.0</Offsetx>
<ServoPlusy>2.4250298</ServoPlusy>
<ServoMinusy>4.217117</ServoMinusy>
<Offsety>0.0</Offsety>
<ServoPlusz>3.1290107</ServoPlusz>
<ServoMinusz>3.2330537</ServoMinusz>
<Offsetz>0.0</Offsetz>
<ServoPlusrx>Infinity</ServoPlusrx>
<ServoMinusrx>Infinity</ServoMinusrx>
<Offsetrx>0.0</Offsetrx>
<ServoPlusry>3.5928729</ServoPlusry>
<ServoMinusry>2.2044537</ServoMinusry>
<Offsetry>0.0</Offsetry>
<Button1>none</Button1>
<Button2>none</Button2>
<Button3>none</Button3>
<Button4>none</Button4>
<Button5>none</Button5>
<Button6>none</Button6>
<InvertButton1>false</InvertButton1>
<InvertButton2>false</InvertButton2>
<InvertButton3>false</InvertButton3>
<InvertButton4>false</InvertButton4>
<InvertButton5>false</InvertButton5>
<InvertButton6>false</InvertButton6>
<Keyboard>112,idleUp1;113,idleUp2;114,autoRotation;115,reset</Keyboard>
</project>
Re: Strange yaw bug or is it me ?
Posted: 18 Jun 2008 08:43
by Michael
Hi,
please calibrate your joystick before its use in HELI-X also within your operating system. Then calibrate in HELI-X.
However, this behavior might be real, depending on your helicopter and the wind settings. Some scale helis have a tailrotor which is not so powerful (as it is in reality, particularly the Lama).
Michael
Re: Strange yaw bug or is it me ?
Posted: 18 Jun 2008 11:30
by Taurim
My radio is calibrated within heli-x. When it is calibrated, the movement of the gauges in the configuration dialog correspond exactly with the movement of the sticks.
stick to the left with minimum gaz, ok. It turns counter clockwise on the ground.
stick to the right with "almost" minimum gaz : ok. It turns clockwise on the ground.
stick to the right with minimum gaz : the helicopter slides rapidly to the left ! No comparison with the slide when the helicopter starts to take off.
The movement looks very unnatural. Maybe 3m/s, constant speed.
Re: Strange yaw bug or is it me ?
Posted: 18 Jun 2008 13:03
by Michael
Ah, ok, now I understand what you mean. This behavior is due to too small friction coefficients for the contact with the ground. Yes, this is unreal. In the coming version there is an imporoved friction model....
Cheers,
Michael
Re: Strange yaw bug or is it me ?
Posted: 18 Jun 2008 14:33
by Taurim
I'm not sure it is the cause of the problem.
I can see what you mean. The heli easily slides when it is on the ground.
But in this case, it is a very unnatural movement.
When I put the rudder to the left on the ground with no power, the heli rotates too easily due to the absence of friction. But the movement is ok.
When I put the rudder to the right on the ground with no power, the heli does not rotate at all. It goes violently to the left in a straight line !!!
If i apply just a little power (far from take off, moving the trim a few millimeters is enough) and put the rudder to the right, the heli acts correctly : it rotates clockwise. Too easily due to no friction but ok.
It's difficult to explain
Oh, by the way, I have found another strange behavior
Sometimes, I fly for 2 or 3 minutes. Everything works perfectly and suddenly the heli start to spin madly. The spin is not correctable with the rudder. I have to hit reset to correct the problem and start again.
Re: Strange yaw bug or is it me ?
Posted: 18 Jun 2008 17:46
by heliseibi
Taurim wrote:...
Oh, by the way, I have found another strange behavior
Sometimes, I fly for 2 or 3 minutes. Everything works perfectly and suddenly the heli start to spin madly. The spin is not correctable with the rudder. I have to hit reset to correct the problem and start again.
Dieses Verhalten ist mir auch schon aufgefallen!
Auch bei mir dreht sich der Heli urplötzlich, wie wenn der Heckrotor ausgefallen wäre!
Re: Strange yaw bug or is it me ?
Posted: 18 Jun 2008 19:46
by Michael
This simulates a tailrotor crash. The right behavior is then to make an autorotation landing and reset the helicopter. This crash appears when the tail of you heli is too deep.
It is also possible to initiate this crash artificially. For this, there is a function tailCrash assignable to a key of the keyboard.
Michael