Authors: Kevin A. Hao, Jennifer A. Nichols
Faculty Mentor: Jennifer A. Nichols
College: Herbert Wertheim College of Engineering
Every day we use our hands to grasp and manipulate objects. Despite this, musculoskeletal models of the hand rarely include contact mechanics, thereby limiting our ability to model hand-object interactions. While contact mechanics are generally absent from upper-extremity models, methods have been developed for studies analyzing gait and implants. This study aims to translate two common contact models (Hunt-Crossley and Elastic Foundation) into the hand to model the fingerpad. Specifically, we evaluate how changes in key contact model parameters influences estimation of finger-tip force. Variation in target force, contact area, and stiffness parameters substantially impacted the accuracy of predicted finger-tip forces in both contact models. Generally, the Hunt-Crossley contact model produced a greater proportion of accurate finger-tip forces than the Elastic Foundation model. Computation time for both contact models increased in response to increasing model parameters. Simulations of the Hunt-Crossley contact model had greater computation time compared to the Elastic Foundation model across the range of target forces tested for large values of contact area and stiffness. Overall, this study demonstrates how contact mechanics can be applied to the hand to model finger-tip forces and provides insight into considerations for choosing a contact model.