An elastic link mechanism integrated with a magnetorheological fluid for elbow orthotics

This study proposes a novel method to change the apparent stiffness of a mechanical link system according to the given magnetic field. We propose an elastic link mechanism integrated with a magnetorheological (MR) fluid that can be controlled by the current of an electrical coil. The potential applications of the proposed device include sports training, physiotherapy, and motor rehabilitation. Compared to a simple weight lifting system, which requires manual changing of weights, this new device allows users to change the load easily and continuously, with relatively lower power consumption. The advantages of the developed link have been verified through several experiments aimed at evaluating its basic characteristics as well as through application to an upper limb orthosis.