-
[show abstract]
[hide abstract]
ABSTRACT: The aim of gait rehabilitation is a restoration of an independent gait and improvement of daily life walking functions. Therefore the specific patterns, that are to be relearned, must be practiced to stimulate the learning process of the central nervous system (CNS). The Walking Simulator HapticWalker allows for the training of arbitrary gait trajectories of daily life. To evaluate the quality of the training a total of 9 subjects were investigated during free floor walking and stair climbing and during the same tasks in two different training modes on the HapticWalker: 1) with and 2) without vertical center of mass (CoM) motion. Electromyograms (EMG) of 8 gait relevant muscles were measured and muscle activation was compared for the various training modes. Besides the muscle activation as an indicator for the quality of rehabilitation training the study investigates if a cancellation of the vertical CoM movement by adaption of the footplate trajectory is feasible i.e. the muscle activation patterns for the two training modes on the HapticWalker agree. Results show no significant differences in activation timing between the training modes. This indicates the feasibility of using a passive patient suspension and emulate the vertical CoM motion by trajectory adaption of the footplates. The muscle activation timing during HapticWalker training shows important characteristics observed in physiological free walking though a few differences can still remain.
Engineering in Medicine and Biology Society, 2008. EMBS 2008. 30th Annual International Conference of the IEEE; 09/2008
-
[show abstract]
[hide abstract]
ABSTRACT: The aim of gait rehabilitation is a restoration of an independent gait and improvement of daily life walking functions. Therefore the specific patterns, that are to be relearned, must be practiced to stimulate the learning process of the central nervous system (CNS). The Walking Simulator HapticWalker allows for the training of arbitrary gait trajectories of daily life. To evaluate the quality of the training a total of 9 subjects were investigated during free floor walking and stair climbing and during the same tasks in two different training modes on the HapticWalker: 1) with and 2) without vertical center of mass (CoM) motion. Electromyograms (EMG) of 8 gait relevant muscles were measured and muscle activation was compared for the various training modes. Besides the muscle activation as an indicator for the quality of rehabilitation training the study investigates if a cancellation of the vertical CoM movement by adaption of the footplate trajectory is feasible i.e. the muscle activation patterns for the two training modes on the HapticWalker agree. Results show no significant differences in activation timing between the training modes. This indicates the feasibility of using a passive patient suspension and emulate the vertical CoM motion by trajectory adaption of the footplates. The muscle activation timing during HapticWalker training shows important characteristics observed in physiological free walking though a few differences can still remain.
Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 02/2008; 2008:1961-4.
-
[show abstract]
[hide abstract]
ABSTRACT: A major criterion for the application of rehabilitation robots in gait therapy is the question to what extent the machine is able to facilitate physiologically correct muscle activation patters in the patients leg muscles in order to achieve an optimal gait training effect. The EMG data presented in this paper is based on intermediate results of a study with 8 healthy subjects (5 male, 3 female) to evaluate the end-effector based gait rehabilitation robot HapticWalker in position controlled mode. The study investigated two different walking trajectories (floor, upstairs) at three different cadences (45, 60, 90 steps/min) in three different modes (free walking, HapticWalker with vertical CoM motion, HapticWalker without vertical CoM motion). Results show that muscle EMGs measured from all relevant leg muscles have the same phasic and rhythmic muscle activation patterns on the HapticWalker as with free walking. Even though there are differences in patterns of dedicated muscles, we observed reduced amplitudes and slightly delayed activation on the HapticWalker compared to free walking. No differences in EMGs were observed between the two different HapticWalker modes (with vertical CoM motion, cancelled CoM motion), which might eliminate the need for an active trunk suspension system in the latter case. A passive patient lifter would significantly reduce the complexity of the machine construction, all advanced training modes (e.g. dynamic body weight reduction) could then be accomplished via compliant behavior of the freely programmable footplates. Numerous EMG measurements with healthy subjects and non-ambulatory stroke patients were performed on the predecessing electromechanical Gait Trainer GT I and showed that physiologically relevant findings from healthy subjects (e.g. correct phasic muscle activation) can be transferred to a certain extent to stroke patients, but nevertheless studies with stroke patients on the robotic gait trainer HapticWalker are needed to con-
firm the results presented in this paper.
Rehabilitation Robotics, 2007. ICORR 2007. IEEE 10th International Conference on; 07/2007
-
[show abstract]
[hide abstract]
ABSTRACT: The control system for a robotic walking simulator and rehabilitation device requires enhanced operation modes and control capabilities, compared to conventional industrial robot controllers. In order to be able to implement custom made algorithms at all levels of the controller and to have an extensible and reusable control environment, we decided to develop a full-featured robot control soft and hardware, including a graphical user interface (GUI), as a modular and open system. This paper describes the newly developed robot and simulator controller, including the graphical user interface, especially those features which distinguish it from conventional robot controllers.
Robotics and Automation, 2004. Proceedings. ICRA '04. 2004 IEEE International Conference on; 01/2004
-
[show abstract]
[hide abstract]
ABSTRACT: Perturbations are an important measure to improve gait training and to investigate the learning success of stroke patients during rehabilitation. This paper describes the development and implementation of algorithms for the synthesis of perturbations during gait training on a robotic walking simulator. The perturbation algorithm performs an automatic on-line adaptation of the robot motion override. Hence, it is independent from the type of motion interpolation which the robot motion is based on. Perturbations we have implemented so far include stumbling, i.e. hitting an obstacle during swing phase, and slipping, i.e. sliding on an obstacle during stance phase. An additional catch-up control algorithm ensures that both feet will regain synchronous motion again after the event The algorithms have been implemented in the control software of the HapticWalker, a programmable footplate based human walking simulator for gait rehabilitation, which we have developed. So far a number of healthy subjects have successfully tested the algorithms on the simulator. Clinical trials will follow.
Rehabilitation Robotics, 2005. ICORR 2005. 9th International Conference on;
