Biomechanical study of upper-limb exoskeleton for resistance training with three-dimensional motion analysis system.

The world's population is aging rapidly, particularly in developed countries. The trend toward prolonged life expectancy will increase the elderly population and thereby lead to an increase in occurrences of age-related health problems such as chronic disease. Healthcare services and home-based rehabilitation are in high demand, and the demand for professional physical therapy is imposing an increasing burden on the healthcare system. Rehabilitation training devices must keep pace with standards of care, be cost effective, and meet the home-based training requirements of today's rehabilitation trends. This article presents an experimental study of a novel spring-loaded upper-limb exoskeleton meant to enable a patient or nondisabled individual to move a limb at multiple joints in different planes for resistance training in a free and unconstrained environment. To assess the functionality of the design, we have measured its kinematic data while performing designated movements and adopted a motion-capture system to verify the function of our mechanism. The collected data and analysis of the kinematic and dynamic joint torques may not only verify our mechanism but also provide a profound understanding of the design requirements for an appropriate spring-loaded exoskeleton for upper-limb resistance training.