artisynth.core.mechmodels

Interface ContactForceBehavior

public interface ContactForceBehavior

Method Summary

Modifier and Type	Method and Description
void	computeResponse(double[] fres, double dist, ContactPoint cpnt1, ContactPoint cpnt2, Vector3d normal, PenetrationRegion region) Computes the force response for a given contact.

Method Detail

computeResponse

void computeResponse(double[] fres,
                     double dist,
                     ContactPoint cpnt1,
                     ContactPoint cpnt2,
                     Vector3d normal,
                     PenetrationRegion region)

Computes the force response for a given contact. The response consists of three values: force, compliance, and damping, all of which should be placed into fres. The force is defined as the restoring force

 force = f(dist)
 

computed in response to the interpenetration distance dist. Note that in general, dist will be negative, and a negative force will be expected in response. The compliance is the reciprocal of the derivative of f(dist) evaluated at dist. The damping is a positive damping parameter used to generate damping forces in response to motion in the contact direction.

Other information the can be used includes the two contact points associated the contact, and the contact normal, which is facing outward from the contact surface.

Parameters:

fres - returns the force, compliance and damping for a given contact distance.

dist - contact interpenetration distance. This value is usually negative, with greater negativity indicating greater interpenetration.

cpnt1 - first contact point

cpnt2 - second contact point

normal - contact normal, facing outward from the surface

region - penetration region on the mesh associated with the first contact point, if available