Data Analysis With A Force-Reflective Joystick

Rough sensitivity data is presented for the problem of `tactile display' of data with a force-reflective joystick. The objective is to let a computer system user feel some parameter that is not otherwise displayed, through a tactile mode of a joystick that has been modified to produce forces, in addition to acting as an input device. The utility of a tactile display technique depends on the user's sensitivity to changes in the tactile parameter. Simple experiments were conducted to collect approximate sensitivity data for several tactile modalities. They indicate that, with the equipment in use, users can recognize three to four bits of data with vibratory feedback, and about two bits with stiffness feedback.