OVERVIEW

This chapter is about locomotion interfaces interfaces that both enable users to move around in real or virtual spaces and make users feel as if they are moving. Locomotion is a special type of movement: Locomotion, as used by life scientists, refers to the act of an organism moving itself from one place to another. This includes actions such as flying, swimming, and slithering. For humans, locomotion is walking, running, crawling, jumping, swimming, and so on. In Figure 4.1, the user moves from one place to another by leaning to control speed and direction of the Segway Personal Transporter (PT); in Figure 4.2, the user is (really) walking on the treadmill (shown in detail on the right) to move through a virtual landscape.

Figure 4.1: Segway i2 self-balancing Personal Transporter. The user controls the speed by leaning forward or backward and turns by leaning to the right or left with the LeanSteer frame. (Courtesy of Segway Inc.)

Figure 4.2: University of Utah's Treadport virtual-locomotion interface. Left: The user walks on a treadmill while viewing the moving virtual landscape on the large projector screens. Right: To simulate hills, the entire treadmill can tilt up. To simulate the user's virtual inertia, the Treadport physically pushes or pulls the user via a large rod that connects to a user-worn harness. (Courtesy of University of Utah, School of Computing; John M. Hollerbach.)

The focus of this chapter is computer-based locomotion interfaces for moving about in...