The examples given so far already seem closely related to VR. A perceptual experience is controlled by body movement that is sensed through a hardware device. Using the universal simulation principle, any of these and more could be brought into a VR system. The physical interaction part might be identical (you could really be holding an Atari Paddle), or it could be simulated through another controller. Think about possible designs.
Using the tracking methods of Chapter 9, the position and orientation of body parts could be reliably estimated and brought into VR. For the case of head tracking, it is essential to accurately maintain the viewpoint with high accuracy and zero effective latency; otherwise, the VR experience is significantly degraded. This is essential because the perception of stationarity must be maintained for believability and comfort. The motion of the sense organ must be matched by a tracking system.