Human hand impedance characteristics during reaching movements

The dynamic characteristics of human arm are usually expressed by mechanical impedance which includes inertia, viscosity and stiffness. This paper aimed to investigate human impedance during maintained posture and reaching movements for the purpose of clarifying human impedance changes depending on different conditions as a first step to realize impedance training for sports and rehabilitation. In this study, a subject was asked to do reaching movements in a virtual sports system to estimate the hand impedance during movements. The experimental results for all 3 subjects in different conditions demonstrate that people may optimally regulate hand impedance properties according to environmental constraints and the desired tasks.