private void createWheels() {
        addWheel(HOVER_HEIGHT_LF_START, new Vector3f(0, -1, 0), new Vector3f(-1, 0, 0), yw, yw, false);
        addWheel(HOVER_HEIGHT_RF_START, new Vector3f(0, -1, 0), new Vector3f(-1, 0, 0), yw, yw, false);
        addWheel(HOVER_HEIGHT_LR_START, new Vector3f(0, -1, 0), new Vector3f(-1, 0, 0), yw, yw, false);
        addWheel(HOVER_HEIGHT_RR_START, new Vector3f(0, -1, 0), new Vector3f(-1, 0, 0), yw, yw, false);
        for (int i = 0; i < 4; i++) {
            getWheel(i).setFrictionSlip(0.001f);
        }
    }
Creates a new PhysicsNode with the supplied collision shape
@param shape the desired collision shape
jme3-examples/src/main/java/jme3test/bullet/PhysicsHoverControl.java