1 Abstract—Intensive task-oriented repetitive physical therapies provided by individualized interaction between the patient and a rehabilitation specialist can improve hand motor performance in patients survived from stroke and traumatic brain injury. However, the therapy process is long and expensive and difficult to evaluate quantitatively and objectively. The goal of this research is to develop a novel wearable device for robotic assisted hand repetitive therapy. We designed a pneumatic muscle (PM) driven therapeutic device that is wearable and provides assistive forces required for grasping and release movements. The robot has two distinct degrees of freedom at the thumb and the fingers. The embedded sensors feedback position and force information for robot control and quantitative evaluation of task performance. It has the potential of providing supplemental at-home therapy in addition to in the clinic treatment. Keywords—Repetitive therapy, fingers, rehabilitation robot, hand motor function I. INTRODUCTION Neurological problems such as stroke and traumatic brain injury are a highly prevalent condition that results in high cost to the individuals and society. Stroke is a leading cause of disability, commonly involving deficits of motor functions. The findings that repetitive motor function activities can induce neural plasticity and result in functional recovery form the basis for new therapeutic treatment of patients who survived stroke and traumatic brain injury. However, traditional approach and technique of repetitive function training for neurological rehabilitation are very labor intensive and lack of consistency and objective assessment. There has been a continuous effort by engineers to develop robotic systems that can assist and improve the rehabilitation outcomes of patients with neuromuscular disabilities. Many robotic systems tend to be expensive and are often developed for research purpose, therefore, too complex for practical use. Manuscript received April 9, 2008. This work is being supported by Key Laboratory of Image Processing and Intelligent Control under Grant 200704, in part by the Natural Science Foundation of China under Grant 60674105, in part by Hi-Tech Research and Development Program of China under Grant 2007AA04Z204, and in part by the Science and Technology Department of Hubei Province under Grant 2007ABA027. Corresponding author Qi Xu is with the Key Laboratory of Image Processing and Intelligent Control, Department of Control Science and Technology, Huazhong University of Science and Technology, Wuhan, China. ( Phone: 86-27-87557284. e-mail: xuqi@mail.hust.edu.cn). There is a need for low cost, safe and practical devices to assist therapy [1]-[6]. Hand is an organ of grasp as well as sensation, fine discrimination and exquisite dexterity. A normally functioning hand is very important for an independent and active life. Unfortunately, the incidence of injuries directly affecting the hand has risen dramatically in the recent years[7]. These injuries include traumatic injuries, congenital deformities, neurological and arthritic conditions, and regional pain syndrome of the hands. Due to the central role that hand movements normally play in human existence, much attention in rehabilitation research has been focused on understanding and restoring hand motor function after injury. There is a need for low cost, safe and practical devices to assist hand therapy. Many kinds of assist devices for hand therapy have been developed to offer many patients the intensive training that is needed for neural reorganisation and functional changes. Some exoskeleton based systems are too heavy and bulky, or too expensive for home use by individuals with hand impairments. A hand exoskeleton based exerciser is designed for the physical and occupational therapy of the hand in an interactive virtual reality environment[8]. A prototype virtual-reality-based telerehabilitation system that uses the Rutgers Master II (RMII) force feedback glove is developed for repetitive hand therapy at home, while allowing remote monitoring from the clinic[9, 10]. Recently, the compliant pneumatic muscle actuators (PMA) have found many applications in the robot-based hand motor therapy. A wearable power assist device [11] for hand grasping is proposed to improve the Quality Of Life (QOL) of elderly and disabled persons. The hand Mentor™[12] is designed to offer active repetitive therapy to the fingers and wrist by encouraging self-powered motion and assisting movement when necessary. The hand wrist assistive rehabilitation device with 3 degrees-of-freedom is developed to assist the hand in grasp and release movements[13]. Compared with the electric motor technology, the PMA is soft and exhibits many of the properties of human muscle. Therefore, the hand therapy device with PMAs can interact with the patient in a safer and more natural way[14]. The device described in this paper is designed to provide 1 Key Laboratory of Image Processing and Intelligent Control, Department of Control Science and Technology, Huazhong University of Science and Technology, Wuhan, China 2 Harrington Department of Bioengineering and Center for Neural Interface Design at the Biodesign Institute, Arizona State University, Tempe, AZ, USA 3 Department of Rehabilitation Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China A Wearable Device for Repetitive Hand Therapy Kexin Xing 1 , Qi Xu 1 , Jiping He 1,2 , Yongji Wang 1 , Zhongwei Liu 1 , Xiaolin Huang 3 Proceedings of the 2nd Biennial IEEE/RAS-EMBS International Conference on Biomedical Robotics and Biomechatronics Scottsdale, AZ, USA, October 19-22, 2008 978-1-4244-2883-0/08/$25.00 ©2008 IEEE 919