Vibration Influences Haptic Perception of Surface Compliance During Walking
A. Users stepped onto vibrating plate a, which was driven by vibration actuator b and mounted on suspension c. The plate displaced in the vertical direction, guided by low-noise ball bearing slides d, and compressing a pair of foam inserts e. To produce the commanded compliance, the foam inserts e were positioned by the linear servomechanisms f before each stimulus presentation, while the plate assembly was lifted by servos g. Participant-applied forces were measured by load cells h under four corners of the plate assembly. B. Image of the apparatus and shoe as used in the experiment. Opaque panels k and fabric (not shown) hid the device configuration from subjects' view. Four optical motion capture markers m tracked the displacement of the plate with high precision.