[ODE] getting negative angle?

[Neelam C]

Well, I do check that my angles dont go beyond the low and high limits, isnt
that enough? If not then why does my other angles (thats are positive desired
angles) work perfectly well.

        if (J3 <kJoint.getLowStop()){
                J3 = kJoint.getLowStop();
        }
        else{
           if (J3 > kJoint.getHighStop()){
                J3 = kJoint.getHighStop();
           }

Regards.


--- Bo Morgan <neptune at MIT.EDU> wrote:

> 
> With angle controllers like this I usually make sure that my angle error
> is between PI and -PI.
> 
> If you add something like:
> 
>   while(angle_error > PI)
>     angle_error -= 2*PI;
> 
>   while(angle_error < -PI)
>     angle_error += 2*PI;
> 
> Would that help?
> 
> Bo
> 
> On Tue, 9 Nov 2004, Neelam C wrote:
> 
> )
> ) Hi all,
> )
> ) How do we get a desired negative angle?
> ) eg:
> ) desired angle = -1.898
> ) actual angle = -0.0045
> )
> ) my code goes as
> )
> ) jointError = desired angle - actual angle;
> ) jointRate = dJointGetHingeAngleRate(jointID);
> ) maxForce = +1200;
> ) pValue = 0.6; dValue 0.1;
> ) needVelocity = (pValue*jointError - dValue*jointRate);
> ) dJointSetHingeParam(kJoint.jointID,     dParamFMax,             maxForce);
> ) dJointSetHingeParam(kJoint.jointID,     dParamVel,             
> needVelocity);
> )
> ) This works very well if I want positive angle but when my desired angle is
> ) negative this sucks!
> )
> ) Regards.
> )
> ) =====
> ) ________________________
> ) Neelam C
> )
> ) http://www.geocities.com/tina_vipul/homepage.html
> )
> )
> )
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=====
________________________
Neelam C

http://www.geocities.com/tina_vipul/homepage.html


		
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