Rehabilitation Robotics

Robotic rehabilitation devices have become increasingly important and popular in clinical and rehabilitation environments to facilitate prolonged duration of training, increased number of repetitions of movements, improved patient safety, less strenuous operation by therapists, and eventually, to improve the therapeutic outcome. Novel assistive technologies are becoming available as wearable devices that allow transferring the therapeutic training into home and work environments or assist the patient in day-to-day activities. This monograph summarizes the rationale for robot-assisted therapy and presents the technological steps in the evolution of the design and development of lower and upper extremity rehabilitation robots. After presenting the basic mechanisms of natural and artificial movement restoration, and the rationale of robot-aided movement therapy, this monograph shows several design criteria that are relevant for the development of effective and safe rehabilitation robots. The robotic design depends on the kind of application (i.e., therapeutic or assistive), and varies with respect to different kinds of actuation and patient interaction principles, robotic complexities, and kinematic approaches. Several examples of gait and arm rehabilitation robots are presented that are in developmental status or already commercially available. Novel patient-cooperative strategies are presented, such as impedance control, assistance-as-needed control and tunnel (path) control. Such patient-cooperative strategies can increase movement variability and patient activity; both can have a positive effect on the therapeutic outcome. Special bio-cooperative control strategies and biofeedback methods are introduced that increase engagement and motivation during the therapy session. Standardized assessment tools implemented in robotic devices have shown to be a convenient and accurate method to evaluate the rehabilitation process of individual patients and entire patient groups, which can allow therapists and researchers to perform better intra and inter-subject comparisons. This monograph, which in several parts has an emphasis on the work from the author's laboratory, finishes with a short overview about existing clinical trials that have been performed showing that the application of rehabilitation devices is at least as effective as the application of conventional therapies. It concludes with the finding that further clinical studies are required to find predictors for the success of a robot-aided treatment.