Abstract
This paper proposes a method of estimating fingertip forces in finger tapping movements based on human fingerpad
characteristics. In this method, first, the relationship between the fingertip force and the displacement, which are caused by elastic deformation between the thumb and index fingerpads, is modeled as a fingerpad-stiffness model. Then, using this model, the force between the two fingertips (the fingertip force) can be estimated from the measured fingerpad deformation only.
In the experiments, fingertip forces and the displacements between the two fingerpads generated when a subject pinched and pushed a force sensor with the thumb and index finger were measured to approximate the relationships between fingerpad force and deformation. The results indicated that human fingerpad characteristics can be expressed using a nonlinear fingerpad-stiffness function, and that fingerpad forces can be estimated using the proposed model. Furthermore, finger tapping forces of Parkinson’s disease (PD) patients were compared with those of healthy subjects. These results lead us to conclude that the finger tapping forces could be used as a new index for evaluating
the finger motor function.
