Large Linear Treadmill
The linear treadmill setup consists of three main components: the treadmill itself (Bonte Technology, Netherlands), a four camera Vicon® MX-13 optical tracking system, and a visualization system that displays 3D graphics in a head-mounted display (see Figure). All three components are controlled by separate dedicated computers.
The linear treadmill measures 6 x 2.4 m (L x W) and is capable of speeds up to 40 km/h. It is controlled from a pc via a CANbus connection. The treadmill can be controlled in either open loop or closed loop mode. For the closed loop control, the position of the user on the treadmill is measured with the Vicon® system, which tracks infrared-reflecting markers on the helmet worn by the user. Based on the position of the helmet and its change over time the speed of the treadmill is adjusted in order to keep the user on the treadmill. The Vicon® data are also used to update the visual input, matching the head movements made by the user. The large linear treadmill is located adjacent to the multi-agent lab.