Osseoperceptive Feedback Enhances Precision Grasp Control in a Virtual Pick-and-Lift Task

Osseoperception, the transmission of vibrotactile and auditory sensations through bone-conducted mechanical stimulation, has recently emerged as a promising modality for delivering artificial sensory feedback in assistive technologies. Prior work demonstrated its feasibility for conveying contact and grasp-force information during prosthetic control. However, its applicability to fine-grained finger-level manipulation remains largely unexplored. This study presents the first implementation of osseoperceptive feedback to support grasp control during a virtual pick-and-lift task requiring precise modulation of grip force to avoid object breakage. Mechanical stimuli were delivered to either the pisiform bone (PB) or the metacarpophalangeal (MCP) joint of the index finger using frequency-specific cues: discrete, auditory-dominant bursts for contact events and continuous, transient vibrotactile signals proportional to grasping force. Twelve participants performed functional grasping tasks under three feedback conditions (PB, MCP, and no-feedback). Results showed that osseoperceptive feedback significantly improved task success compared to no-feedback, with the MCP condition yielding the highest performance and lowest error rates. Conversely, PB stimulation—although subjectively perceived as intuitive due to combined auditory and vibrotactile sensations—resulted in more errors. These findings demonstrate that distal osseoperception can effectively support precision grasp control and open the door to applications beyond prosthetics, such as exoskeletons, teleoperation, and sensory rehabilitation.