For the motions of other body parts, this perfect matching is not critical. Our neural systems can instead learn associations that are preferable in terms of comfort, in the same way as the Atari Paddle, mouse, and keyboard work in the real world. Thus, we want to do remapping, which involves learning a sensorimotor mapping that produces different results in a virtual world than one would expect from the real world. The keyboard example above is one of the most common examples of remapping. The process of pushing a pencil across paper to produce a letter has been replaced by pressing a key. The term remapping is even used with keyboards to mean the assignment of one or more keys to another key.
Remapping is natural for VR. For example, rather than reaching out to grab a virtual door knob, one could press a button to open the door. For a simpler case, consider holding a controller for which the pose is tracked through space, as allowed by the HTC Vive system. A scaling parameter could be set so that one centimeter of hand displacement in the real world corresponds to two centimeters of displacement in the virtual world. This is similar to the scaling parameter for the mouse. Section 10.2 covers the remapping from natural walking in the real world to achieving the equivalent in a virtual world by using a controller. Section 10.3 covers object interaction methods, which are again achieved by remappings. You can expect to see many new remapping methods for VR in the coming years.
Steven M LaValle 2020-11-11