getState() method of the PositionSensorVRDevice interface returns the current state of the position sensor for the current frame (e.g. within the current window.requestAnimationFrame callback) or for the previous frame, contained with a VRPositionState object. This is the method you'd normally want to use, versus PositionSensorVRDevice.getImmediateState.resetSensor() method of the VRDevice interface can be used to reset the sensor if desired, returning the position and orientation values to zero.