An electrically actuated lower extremity exoskeleton is developed, in which only the knee joint is actuated actively while other joints linked by elastic elements are actuated passively. This paper describes the criti...An electrically actuated lower extremity exoskeleton is developed, in which only the knee joint is actuated actively while other joints linked by elastic elements are actuated passively. This paper describes the critical design criteria and presents the process of design and calculation of the actuation system. A flexible physical Human-Robot-Interaction （pHR1） measurement device is designed and applied to detect the human movement, which comprises two force sensors and two gasbags attached to the inner surface of the connection cuff. An online adaptive pHRI minimization control strategy is proposed and implemented to drive the robotic exoskelcton system to follow the motion trajectory of human limb. The measured pHRI information is fused by the Variance Weighted Average （VWA） method. The Mean Square Values （MSV） of pHRI and control torque are utilized to evaluate the performance of the exoskeleton. To improve the comfort level and reduce energy consumption, the gravity compensation is taken into consideration when the control law is designed. Finally, practical experiments are performed on healthy users. Experimental results show that the proposed system can assist people to walk and the outlined control strategy is valid and effective.展开更多
Bilateral rehabilitation systems with bilateral or unilateral assistive robots have been developed for hemiplegia patients to recover their one-side paralysis.However,the compliant robotic assistance to promote bilate...Bilateral rehabilitation systems with bilateral or unilateral assistive robots have been developed for hemiplegia patients to recover their one-side paralysis.However,the compliant robotic assistance to promote bilateral inter-limb coordination remains a challenge that should be addressed.In this paper,a biomimetic variable stiffness modulation strategy for the Variable Stiffness Actuator(VSA)integrated robotic is proposed to improve bilateral limb coordination and promote bilateral motor skills relearning.An Electromyography(EMG)-driven synergy reference stiffness estimation model of the upper limb elbow joint is developed to reproduce the muscle synergy effect on the affected side limb by independent real-time stiffness control.Additionally,the bilateral impedance control is incorporated for realizing compliant patient-robot interaction.Preliminary experiments were carried out to evaluate the tracking performance and investigate the multiple task intensities’influence on bilateral motor skills relearning.Experimental results evidence the proposed method could enable bilateral motor task skills relearning with wide-range task intensities and further promote bilateral inter-limb coordination.展开更多
文摘An electrically actuated lower extremity exoskeleton is developed, in which only the knee joint is actuated actively while other joints linked by elastic elements are actuated passively. This paper describes the critical design criteria and presents the process of design and calculation of the actuation system. A flexible physical Human-Robot-Interaction （pHR1） measurement device is designed and applied to detect the human movement, which comprises two force sensors and two gasbags attached to the inner surface of the connection cuff. An online adaptive pHRI minimization control strategy is proposed and implemented to drive the robotic exoskelcton system to follow the motion trajectory of human limb. The measured pHRI information is fused by the Variance Weighted Average （VWA） method. The Mean Square Values （MSV） of pHRI and control torque are utilized to evaluate the performance of the exoskeleton. To improve the comfort level and reduce energy consumption, the gravity compensation is taken into consideration when the control law is designed. Finally, practical experiments are performed on healthy users. Experimental results show that the proposed system can assist people to walk and the outlined control strategy is valid and effective.
文摘Bilateral rehabilitation systems with bilateral or unilateral assistive robots have been developed for hemiplegia patients to recover their one-side paralysis.However,the compliant robotic assistance to promote bilateral inter-limb coordination remains a challenge that should be addressed.In this paper,a biomimetic variable stiffness modulation strategy for the Variable Stiffness Actuator(VSA)integrated robotic is proposed to improve bilateral limb coordination and promote bilateral motor skills relearning.An Electromyography(EMG)-driven synergy reference stiffness estimation model of the upper limb elbow joint is developed to reproduce the muscle synergy effect on the affected side limb by independent real-time stiffness control.Additionally,the bilateral impedance control is incorporated for realizing compliant patient-robot interaction.Preliminary experiments were carried out to evaluate the tracking performance and investigate the multiple task intensities’influence on bilateral motor skills relearning.Experimental results evidence the proposed method could enable bilateral motor task skills relearning with wide-range task intensities and further promote bilateral inter-limb coordination.
