Design and Implementation of a Robotic Testbench for Analyzing Pincer Grip Execution in Human Specimen Hands

This study presents an innovative test rig engi- neered to explore the kinematic and viscoelastic characteris- tics of human specimen hands. The rig features eight force- controlled motors linked to muscle tendons, enabling precise stimulation of hand specimens. Hand movements are monitored through an optical tracking system, while a force-torque sensor quantifies the resultant fingertip loads. Employing this setup, we successfully demonstrated a pincer grip using a cadaver hand and measured both muscle forces and grip strength. Our results reveal a nonlinear relationship between tendon forces and grip strength, which can be modeled by an exponential fit. This investigation serves as a nexus between biomechanical and robotics-focused research, providing critical insights for the advancement of robotic hand actuation and therapeutic interventions.