Developments in locomotion interfaces

This paper describes the Sarcos Treadport locomotion interface, a large tilting treadmill whose unique aspect is the application of forces to a user´s torso. The application of torso forces is necessary to provide missing inertial forces during acceleration on a treadmill and to stop a user from walking through virtual walls. Torso forces can also substitute for treadmill tilt, as has been validated by psychological, biomechanical and energetic studies. A harness has been designed to transmit forces to the torso with minimum backlash while maintaining comfort. The experience of locomotion is integrated into a virtual environment comprised of a CAVE-like visual display and head-tracked stereo sound synthesis. To complete the multi-sensory experience, atmospheric and olfactory displays are under development.