Tools for understanding and optimizing robotic gait training

Abstract

Abstract-This article reviews several tools we have developed to improve the understanding of locomotor training following spinal cord injury (SCI), with a view toward implementing locomotor training with robotic devices. We have developed (1) a small-scale robotic device that allows testing of locomotor training techniques in rodent models, (2) an instrumentation system that measures the forces and motions used by experienced human therapists as they manually assist leg movement during locomotor training, (3) a powerful, lightweight leg robot that allows investigation of motor adaptation during stepping in response to force-field perturbations, and (4) computational models for locomotor training. Results from the initial use of these tools suggest that an optimal gait-training robot will minimize disruptive sensory input, facilitate appropriate sensory input and gait mechanics, and intelligently grade and time its assistance. Currently, we are developing a pneumatic robot designed to meet these specifications as it assists leg and pelvic motion of people with SCI.

Design and Evaluation of the LOPES Exoskeleton Robot for Interactive Gait Rehabilitation

“…This is also reflected in current research on robotic neurorehabilitation [8], [15], [16]. These facts call for a device that allows near-tonormal free walking and that allows providing a wide range of possible content of training and supportive actions, while safety (for both patient and therapist) is assured at any time.…”

“…All eight DOFs not only allow the exoskeleton to make a forward stepping motion (as provided by the Lokomat and the AutoAmbulator), but also maintain the fundamental instability of a standing or walking human. As such, balance control still has to be achieved when walking in the device, either by the human or (when necessary) by the robot, and is widely recognized as an important aspect of gait training [8], [20]. Table I describes which DOFs are possible for a human being, which of these are actuated in the robot, which are left free, and which are blocked.…”

“…Current automated gait trainers, such as the Lokomat (Hocoma, AG, Volketswil, Switzerland) [7], the pneumatically operated gait orthosis and the pelvic assist manipulator (known as POGO and PAM, respectively; not commercially available) [8], the GaitTrainer (Reha-Stim, Berlin, Germany) [9], the Haptic Walker (not commercially available) [10], and the AutoAmbulator (HealthSouth Cooperation), are usually unable to fully adapt their movements to the activity of the patient. Some devices are not able to assist all possible leg movements, but for example only foot movement.…”

Versatile robotic interface to evaluate, enable and train locomotion and balance after neuromotor disorders

“…There is evidence suggesting that gait rehabilitation should be conducted overground 23 across multiple walking paradigms 7 , with adequate support conditions [23][24][25] , enabling systems 1,12,19,22,24 , task-specific sensory cues 1,12 and active patient cooperation 20,22 , but these concepts remain fragmented. Our versatile propulsive and postural neuroprosthetic interface crystallizes these views into a unified therapeutic tool to evaluate and restore locomotor function after CNS disorders, both in animals and in humans.…”

Characterization of unexpected postural changes during robot-assisted gait training in paraplegic patients

“…A previous study also reported that it is necessary to perform sufficient gait training before progressing to robot-assisted gait. 14 For 2 years, the average rate of the incidence of UPCs was 0.96 ± 0.62 (incidents/h/subject). Until now, there is no study on the rate of fall frequency during robot-assisted gait training in SCI patients.…”