Pseudo-haptic feedback: can isometric input devices simulate force feedback?

TLDR

The study investigates whether a passive isometric input device combined with visual feedback can deliver pseudo‑haptic feedback to the operator. Two psychophysical experiments were performed: one comparing compliance of two virtual springs via the Spaceball, and another comparing a virtual spring to a real spring. The experiments revealed compliance JNDs of 6% and 13.4%, matching manual discrimination results and indicating that the passive device can partially simulate haptic information, though visual feedback blurs proprioception and creates an illusion of a nonisometric device.

Abstract

This paper considers whether a passive isometric input device, such as a Spaceball/sup TM/, used together with visual feedback, could provide the operator with a pseudo-haptic feedback. For this aim, two psychophysical experiments have been conducted. The first experiment consisted of a compliance discrimination, between two virtual springs hand-operated by means of the Spaceball/sup TM/. In this experiment, the stiffness (or compliance) JND turned out to be 6%. The second experiment assessed stiffness discrimination between a virtual spring and the equivalent spring in reality. In this case, the stiffness (or compliance) JND was found to be 13.4%. These results are consistent with previous outcomes on manual discrimination of compliance. Consequently, this consistency reveals that the passive apparatus that was used can, to some extent, simulate haptic information. In addition, a final test indicated that the proprioceptive sense of the subjects was blurred by visual feedback. This gave them the illusion of using a nonisometric device.