Now showing 1 - 9 of 9
  • Publication
    Richtlinien für die Gestaltung von visuellem Biofeedback in der neurologischen Gangrehabilitation nach Schlaganfall
    ( 2010)
    Brüning, M.
    ;
    Hussein, S.
    ;
    Bardeleben, A.
    ;
    Schmidt, H.
    ;
    Krüger, J.
    ;
    Hesse, S.
  • Publication
    Visuelles Biofeedback für die gerätegestützte neurologische Gangrehabilitation nach Schlaganfall
    ( 2010)
    Brüning, M.
    ;
    Hussein, S.
    ;
    Bardeleben, A.
    ;
    Schmidt, H.
    ;
    Krüger, J.
    ;
    Hesse, S.
  • Publication
    Effect of different training modes on ground reaction forces during robot assisted floor walking and stair climbing
    ( 2009)
    Hussein, S.
    ;
    Schmidt, H.
    ;
    Hesse, S.
    ;
    Krüger, J.
    The HapticWalker is a robotic walking simulator for neurological gait rehabilitation. The device is based on the end-effector principle, i.e. the patients' feet are fixed on two footplates, his trunk is secured via a suspension harness. The footplates (end-effectors) of the robot guide the feet of the patient on freely programmable trajectories. Currently two different training modes are provided for each foot trajectory on the HapticWalker. Firstly training trajectories based on real motion capture data can be used. Secondly the vertical center of mass (CoM) motion can be incorporated into the foot trajectory. The latter method leaves the absolute position of the CoM constant, while the relative movement between CoM and feet remains the same as in free walking. Thereby the v ertical CoM motion can be actively supported by using a fixed passive suspension, any type of controlled body weight support will then be accomplished via force controlled footplates. To characterize the training on the machine in position controlled mode, muscle activities as well as ground reaction force data of healthy subjects were collected. This article presents preliminary results from the investigation of ground reaction force data of healthy subjects. Therefore data of 10 healthy subjects was used to compare HapticWalker training modes vs. free walking on level ground and upstairs without any assistive devices and the aforementioned two HapticWalker training modes against each other. Amplitude and timing of force peaks during heel strike, foot flat and push off in vertical ground reaction forces were used for the assessment. In spite of a footplate, which does not provide a separate metatarsal joint for relative motion between fore and hind foot, during heel strike and push off the known characteristic peaks at the beginning and the end of the stance phase can be clearly distinguished. Though compared to free walking a slower and premature rise and slower decline of ground reaction for- ces can be seen due to the stiff guidance of the feet in position controlled mode. No significant differences appeared between the two described HapticWalker training modes.
  • Publication
    Multimodal biofeedback architecture for an electromechanical gait rehabilitation device
    ( 2009)
    Hussein, S.
    ;
    Schmidt, H.
    ;
    Hesse, S.
    ;
    Krüger, J.
  • Publication
    Ground reaction forces during different floor walking in robot assisted gait training
    ( 2009)
    Hussein, S.
    ;
    Schmidt, H.
    ;
    Hesse, S.
    ;
    Krüger, J.
  • Publication
    Gait machines and robots to support motor rehabilitation after stroke
    ( 2007)
    Schmidt, H.
    ;
    Hussein, S.
    ;
    Werner, C.
    ;
    Bernhardt, R.
    ;
    Hesse, S.
    ;
    Krüger, J.
    The group at Klinik Berlin/Charite University Hospital in Berlin, Germany, began studies to promote motor recovery after stroke in the early 1990s. Following the introduction of treadmill training with partial body-weight support, the group designed an electromechanical gait trainer, GT I, based on movable foot plates that relieve therapist effort (e.g., when assisting the movement of the paretic limbs) and intensify patient gait training (GT). Preliminary results of a recent multicenter trial of 155 acute stroke patients showed that the GT I effectively promotes gait ability and competence in activities of daily living. The experimental group received 20 min of GT and 25 min of physiotherapy (PT) and the control group received 45 min of PT every day for 4 weeks. The laboratory's next step was the HapticWalker, a robotic walking simulator with freely programmable foot plates which was designed and built in close collaboration with the Fraunhofer Institute IPK. On this machine patients can, for example, additionally train for stair climbing and perturbations. The foot plates can be operated in full guidance or compliance control modes, thus reducing foot support according to the patient's learning success. Entnommen aus TEMA
  • Publication
    Muscle activation patterns of healthy subjects during floor walking and stair climbing on an end-effector-based gait rehabilitation robot
    ( 2007)
    Schmidt, H.
    ;
    Volkmar, M.
    ;
    Werner, C.
    ;
    Helmich, I.
    ;
    Piorko, F.
    ;
    Krüger, J.
    ;
    Hesse, S.
    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, the authors 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 HapticWalke. Entnommen aus TEMA
  • Publication
    Machines and robots to support motor rehabilitation after stroke
    ( 2007)
    Schmidt, H.
    ;
    Werner, C.
    ;
    Bernhardt, R.
    ;
    Hesse, S.
    ;
    Krüger, J.