Joining other nodes to vehicle

Troubleshooting physics
1

I am trying to join car suspension to vehicle chassis and wheels. I have suspension divided in 4 parts like this.

orange cylinder is inner part, green cylinder if outer part, both black spheres are for joining points. top sphere is for attach tochassis and bottom black is to wheel.

I have also added 4 sphere points to get location on chassis so that I can attach outer part of suspension. You’ll see orange marks in wire frame below.

I am able to attach green cylinder to chassi.

Now I am puzzled, how to attache orange part to wheel center and how to join both suspension parts together. In this case there should be three joins to one complete suspension for one wheel.

I tried to use slid join for suspension parts. but these are looks like hinging balloons.

see below code I used.

private void makeSusp(Geometry suspJoin, Geometry wheel) {
Node suspNode = (Node) assetManager.loadModel(“Models/Susp/Susp.j3o”);

    Geometry suspOut = findGeom(suspNode, "SuspOUT");
    suspOut.center();
    Geometry suspOutJoin = findGeom(suspNode, "SuspOutJoin");
    suspOutJoin.center();
    Geometry suspIn = findGeom(suspNode, "SuspIN");
    suspIn.center();
    Geometry suspInJoin = findGeom(suspNode, "SuspInJoin");
    suspInJoin.center();

    Node suspOuterNode = new Node("SuspOuterNode");
    suspOuterNode.attachChild(suspOutJoin);
    suspOuterNode.attachChild(suspOut);

    Node suspInnerNode = new Node("SuspInnerNode");
    suspInnerNode.attachChild(suspInJoin);
    suspInnerNode.attachChild(suspIn);

    BoundingVolume suspBox = suspJoin.getModelBound();

    BoundingVolume innerBox = suspInJoin.getModelBound();
    BoundingVolume outerBox = suspOutJoin.getModelBound();

    CollisionShape suspInHull = CollisionShapeFactory.createDynamicMeshShape(suspIn);
    CollisionShape suspOutHull = CollisionShapeFactory.createDynamicMeshShape(suspOut);

    RigidBodyControl inControl = new RigidBodyControl(suspInHull);
    suspInnerNode.addControl(inControl);
    rootNode.attachChild(suspInnerNode);
    getPhysicsSpace().add(inControl);

    RigidBodyControl outControl = new RigidBodyControl(suspOutHull, 10f);
    suspOuterNode.addControl(outControl);
    rootNode.attachChild(suspOuterNode);
    getPhysicsSpace().add(outControl);
    outControl.setPhysicsLocation(suspBox.getCenter());

    PhysicsJoint join = join(suspOuterNode, carNode, 
            suspOuterNode.getControl(RigidBodyControl.class), vehicleControl, 
            suspBox.getCenter(), outerBox.getCenter());
    getPhysicsSpace().add(join);

    //joint
    SliderJoint slider=new SliderJoint(outControl, inControl, innerBox.getCenter(), outerBox.getCenter(), false);
    slider.setUpperLinLimit(.1f);
    slider.setLowerLinLimit(-.1f);
    getPhysicsSpace().add(slider);

}

can any one help me, how can I join other nodes to vehicle? Am I doing it in correct way?

2

I wouldn’t actually connect the physics objects, just make it a geometry and move it based on the geometry location of wheel and chassis.

3

Do you mean, just need to simply place all 4 suspension parts in location wheel and chassi?

4

No I say you should compute the correct position for each frame based on the location of the wheel and chassis.