Examples with LinearAxialMaterial artisynth.core.materials.LinearAxialMaterial used on opensource projects

Example 1 with LinearAxialMaterial

use of artisynth.core.materials.LinearAxialMaterial in project artisynth_core by artisynth.

the class AxialSpringTest method testForceAndJacobians.

private void testForceAndJacobians(AxialSpring spring) {
    Vector3d u = new Vector3d();
    Matrix3d uuT = new Matrix3d();
    Matrix3d Iminus_uuT = new Matrix3d();
    Vector3d delv = new Vector3d();
    Matrix3d udelvT = new Matrix3d();
    double l;
    Vector3d f = new Vector3d();
    Matrix3d Fxx = new Matrix3d();
    Matrix3d Fvv = new Matrix3d();
    Vector3d fcheck = new Vector3d();
    LinearAxialMaterial mat = (LinearAxialMaterial) spring.getMaterial();
    double k = mat.getStiffness();
    double d = mat.getDamping();
    double r = spring.getRestLength();
    Point pnt0 = spring.getFirstPoint();
    Point pnt1 = spring.getSecondPoint();
    Point3d pos = new Point3d();
    Vector3d vel = new Vector3d();
    pos.setRandom();
    vel.setRandom();
    pnt0.setPosition(pos);
    pnt1.setVelocity(vel);
    pos.setRandom();
    vel.setRandom();
    pnt0.setPosition(pos);
    pnt1.setVelocity(vel);
    SparseNumberedBlockMatrix S = createJacobian(spring);
    u.sub(pnt1.getPosition(), pnt0.getPosition());
    l = u.norm();
    u.scale(1 / l);
    uuT.outerProduct(u, u);
    Iminus_uuT.setIdentity();
    Iminus_uuT.sub(uuT);
    delv.sub(pnt1.getVelocity(), pnt0.getVelocity());
    udelvT.outerProduct(u, delv);
    double fmag = k * (l - r) + d * delv.dot(u);
    fcheck.scale(fmag, u);
    spring.computeForce(f);
    if (!f.epsilonEquals(fcheck, 1e-10)) {
        throw new TestException("\nforce is " + f.toString("%10.5f") + ", expected " + fcheck.toString("%10.5f"));
    }
    spring.computeForcePositionJacobian(Fxx);
    Matrix3d FxxCheck = checkForcePositionJacobian(spring);
    if (!Fxx.epsilonEquals(FxxCheck, 1e-10)) {
        System.out.println("pos0=" + pnt0.getPosition());
        System.out.println("vel0=" + pnt0.getVelocity());
        System.out.println("pos1=" + pnt1.getPosition());
        System.out.println("vel1=" + pnt1.getVelocity());
        throw new TestException("\nFxx is\n" + Fxx.toString("%10.5f") + "expected\n" + FxxCheck.toString("%10.5f"));
    }
    // if (!(pnt0 instanceof PlanarComponent) &&
    // !(pnt1 instanceof PlanarComponent))
    // {
    // Matrix3d FxxDiscrete = discreteForcePositionJacobian (spring);
    // if (!Fxx.epsilonEquals (FxxDiscrete, 1e-4))
    // { throw new TestException (
    // "\nFxx is\n"+Fxx.toString("%10.5f")+
    // "expected\n"+FxxDiscrete.toString("%10.5f"));
    // }
    // }
    spring.computeForceVelocityJacobian(Fvv);
    Matrix3d FvvCheck = checkForceVelocityJacobian(spring);
    if (!Fvv.epsilonEquals(FvvCheck, 1e-10)) {
        throw new TestException("\nFvv is\n" + Fvv.toString("%10.5f") + "expected\n" + FvvCheck.toString("%10.5f"));
    }
    // if (!(pnt0 instanceof PlanarComponent) &&
    // !(pnt1 instanceof PlanarComponent))
    // {
    // Matrix3d FvvDiscrete = discreteForceVelocityJacobian (spring);
    // if (!Fvv.epsilonEquals (FvvDiscrete, 1e-4))
    // { throw new TestException (
    // "\nFvv is\n"+Fvv.toString("%10.5f")+
    // "expected\n"+FvvDiscrete.toString("%10.5f"));
    // }
    // }
    // now test full Jacobian calculation
    spring.addSolveBlocks(S);
    spring.addPosJacobian(S, 1);
    checkJacobian(S, spring, Fxx);
    S.setZero();
    spring.addVelJacobian(S, 1);
    checkJacobian(S, spring, Fvv);
}

Example 2 with LinearAxialMaterial

use of artisynth.core.materials.LinearAxialMaterial in project artisynth_core by artisynth.

the class PointSpringBase method setStiffness.

public static void setStiffness(PointSpringBase s, double k) {
    if (s.getMaterial() instanceof LinearAxialMaterial) {
        LinearAxialMaterial mat = (LinearAxialMaterial) s.getMaterial().clone();
        mat.setStiffness(k);
        s.setMaterial(mat);
    } else {
        System.out.println("Warning: setStiffness(): no stiffness in spring material");
    }
}

Example 3 with LinearAxialMaterial

use of artisynth.core.materials.LinearAxialMaterial in project artisynth_core by artisynth.

the class PointSpringBase method setDamping.

public static void setDamping(PointSpringBase s, double d) {
    if (s.getMaterial() instanceof LinearAxialMaterial) {
        LinearAxialMaterial mat = (LinearAxialMaterial) s.getMaterial().clone();
        mat.setDamping(d);
        s.setMaterial(mat);
    } else if (s.getMaterial() instanceof AxialMuscleMaterial) {
        AxialMuscleMaterial mat = (AxialMuscleMaterial) s.getMaterial().clone();
        mat.setDamping(d);
        s.setMaterial(mat);
    } else {
        System.out.println("Warning: setDamping(): no damping in spring material");
    }
}