In this paper, a method of using a root hinge drive assembly （RHDA） to control the solar array deployment is provided and a multi-DOF mechanism dynamic model of the system is established. In this way, the root hinge...In this paper, a method of using a root hinge drive assembly （RHDA） to control the solar array deployment is provided and a multi-DOF mechanism dynamic model of the system is established. In this way, the root hinge torque can be calculated iteratively. Then taking the predicted torque as a reference, a RHDA is designed for a large multiple-stage packaging and deployable solar array system. The control effect of the drive assembly is validated by ground tests. The test results indicate that the solar arrays can be deployed smoothly, and the deployment velocities are restricted by the drive assembly as expected. During the tests, the RHDA output speed and output torque are obtained. In order to examine the impact force when the yoke is lock-up with a hard stop, dynamics simulations are performed according to the actual behavior. The simulation result indicates that the designed RHDA reduces the impact force significantly and improves the lock-up reliability effectively.展开更多
This paper mainly presents a PM multi-DOF actuator for robot in-wheels drive applications and its control method. The torque model is established based on the finite-element model of the single pair poles in 3D finite...This paper mainly presents a PM multi-DOF actuator for robot in-wheels drive applications and its control method. The torque model is established based on the finite-element model of the single pair poles in 3D finite element method software. Due to the special structure of the actuator,the Euler angles are adopted for deriving the kinematics and dynamic model. To reduce the effects of uncertainties of modeling error,nonlinear friction and external disturbances in the system,an approximation of neural network adaptive control method is applied to the actuator. The computation and simulation results show that the proposed analysis and control method can effectively derive the characteristics and improve the motion performance,which provides the primary theoretical guide for the configuration design,optimization and control research of multi-DOF deflection type actuators.展开更多
According to clinical studies,upper limb robotic suits are vital to reduce therapist fatigue and accelerate patient rehabilitation.Soft pneumatic actuators have drawn increasing attention for the development of wearab...According to clinical studies,upper limb robotic suits are vital to reduce therapist fatigue and accelerate patient rehabilitation.Soft pneumatic actuators have drawn increasing attention for the development of wearable robots due to their low weight,flexibility,and high power-to-weight ratio.However,most of current actuators were designed for the flexion assistance of a specific joint,and that for joint extension requires further investigation.Furthermore,designing an actuator for diverse working scenarios remains a challenge.In this paper,we propose an all-fabric bi-directional actuator to assist the flexion and extension of the elbow,wrist,and fingers.A mathematical model is presented that predicts the deformation and guides the design of the proposed bi-directional actuator.To further validate the applicability and adaptability of the proposed actuator for different joints,we developed a 3-DOF soft robotic suit.Preliminary results show that the robotic suit can assist the motion of the elbow,wrist,and finger of the subject.展开更多
基金Ph.D. Programs Foundation of Ministry of Education of China (200800060009)
文摘In this paper, a method of using a root hinge drive assembly （RHDA） to control the solar array deployment is provided and a multi-DOF mechanism dynamic model of the system is established. In this way, the root hinge torque can be calculated iteratively. Then taking the predicted torque as a reference, a RHDA is designed for a large multiple-stage packaging and deployable solar array system. The control effect of the drive assembly is validated by ground tests. The test results indicate that the solar arrays can be deployed smoothly, and the deployment velocities are restricted by the drive assembly as expected. During the tests, the RHDA output speed and output torque are obtained. In order to examine the impact force when the yoke is lock-up with a hard stop, dynamics simulations are performed according to the actual behavior. The simulation result indicates that the designed RHDA reduces the impact force significantly and improves the lock-up reliability effectively.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51107031,50677013)the Natural Science Foundation of Hebei Province of China(Grant No.E2009000703)
文摘This paper mainly presents a PM multi-DOF actuator for robot in-wheels drive applications and its control method. The torque model is established based on the finite-element model of the single pair poles in 3D finite element method software. Due to the special structure of the actuator,the Euler angles are adopted for deriving the kinematics and dynamic model. To reduce the effects of uncertainties of modeling error,nonlinear friction and external disturbances in the system,an approximation of neural network adaptive control method is applied to the actuator. The computation and simulation results show that the proposed analysis and control method can effectively derive the characteristics and improve the motion performance,which provides the primary theoretical guide for the configuration design,optimization and control research of multi-DOF deflection type actuators.
基金The research is supported by the National Natural Science Foundation of China(52275002)the Open Laboratory Concept Verification Project of Zhongguancun National Demonstration Zone(Grant No.202005226).
文摘According to clinical studies,upper limb robotic suits are vital to reduce therapist fatigue and accelerate patient rehabilitation.Soft pneumatic actuators have drawn increasing attention for the development of wearable robots due to their low weight,flexibility,and high power-to-weight ratio.However,most of current actuators were designed for the flexion assistance of a specific joint,and that for joint extension requires further investigation.Furthermore,designing an actuator for diverse working scenarios remains a challenge.In this paper,we propose an all-fabric bi-directional actuator to assist the flexion and extension of the elbow,wrist,and fingers.A mathematical model is presented that predicts the deformation and guides the design of the proposed bi-directional actuator.To further validate the applicability and adaptability of the proposed actuator for different joints,we developed a 3-DOF soft robotic suit.Preliminary results show that the robotic suit can assist the motion of the elbow,wrist,and finger of the subject.
