Design and control of an upper limb rehabilitation support device for disabled people using a pneumatic cylinder

Purpose – The purpose of this paper is to describe the development of a device to support rehabilitation of a patient's upper limb motion. Design/methodology/approach – The device has five degrees of freedom by virtue of its link mechanism. It consists of Joints 1‐5. Apparatus for use in so‐called welfare applications, such as this device, must be safe, flexible, and lightweight. A pneumatic cylinder, arranged and integrated with the device, was used to operate it. The device has two rehabilitation modes corresponding to different rehabilitation contents. The first mode is the muscular recovery and movable region expansion mode (Mode A). The second mode is a practical function recovery mode (Mode B). A compliance control and a position control system are applied for those modes. Findings – By arranging the pneumatic cylinder optimally, results show that the device has compact and wide operating range and compliance‐control performance for Mode A. Position‐control performance for Mode B was verified experimentally. Moreover, the paper evaluates the effectiveness of the device and its control system through electromyography, which confirms that the developed device can support a patient's rehabilitation training. Originality/value – The device has a simple link mechanism and an attached pneumatic cylinder, thereby constituting a lightweight and compact mechanism. The device has two rehabilitation modes corresponding to different rehabilitation contents. Using the device, a patient can conduct muscular power recovery training, movable region expansion training, and upper limb practical function recovery training.