public void steer(int wheel, float value) {
        vehicle.setSteeringValue(value, wheel);
    }
Set the given steering value to the given wheel (0 = forward)
@param wheel the wheel to set the steering on
@param value the steering angle of the front wheels (Pi = 360deg)
jme3-jbullet/src/main/java/com/jme3/bullet/objects/PhysicsVehicle.java