A wearable force-feedback glove is a promising way to enhance the immersive sensation when a user interacts with virtual objects in virtual reality scenarios.Design challenges for such a glove include allowing a large...A wearable force-feedback glove is a promising way to enhance the immersive sensation when a user interacts with virtual objects in virtual reality scenarios.Design challenges for such a glove include allowing a large fingertip workspace,providing a desired force sensation when simulating both free-and constrained-space interactions,and ensuring a lightweight structure.In this paper,we present a forcefeedback glove using a pneumatically actuated mechanism mounted on the dorsal side of the user’s hand.By means of a triple kinematic paired link with a curved sliding slot,a hybrid cam-linkage mechanism is proposed to transmit the resistance from the pneumatic piston rod to the fingertip.In order to obtain a large normal component of the feedback force on the user’s fingertip,the profile of the sliding slot was synthesized through an analysis of the force equilibrium on the triple kinematic paired link.A prototype five-fingered glove with a mass of 245 g was developed,and a wearable force-measurement system was constructed to permit the quantitative evaluation of the interaction performance in both free and constrained space.The experimental results confirm that the glove can achieve an average resistance of less than 0.1 N in free-space simulation and a maximum fingertip force of 4 N in constrained-space simulation.The experiment further confirms that this glove permits the finger to move freely to simulate typical grasping gestures.展开更多
A novel hybrid perfusion manipulator(HPM)with five degrees of freedom(DOFs)is introduced by combining the 5PUS-PRPU(P,R,U and S represent prismatic,revolute,universal and spherical joint,respectively)parallel mechanis...A novel hybrid perfusion manipulator(HPM)with five degrees of freedom(DOFs)is introduced by combining the 5PUS-PRPU(P,R,U and S represent prismatic,revolute,universal and spherical joint,respectively)parallel mechanism with the 5PRR reconfigurable base to enhance the perfusion efficiency of the large-scale spherical honeycomb thermal protection layer.This study mainly presents the dimensional synthesis of the proposed HPM.First,the inverse kinematics,including the analytic expression of the rotation angles of the U joint in the PUS limb,is obtained,and mobility analysis is conducted based on screw theory.The Jacobian matrix of 5PUS-PRPU is also determined with screw theory and used for the establishment of the objective function.Second,a global and comprehensive objective function(GCOF)is proposed to represent the Jacobian matrix’s condition number.With the genetic algorithm,dimensional synthesis is conducted by minimizing GCOF subject to the given variable constraints.The values of the designed variables corresponding to different configurations of the reconfigurable base are then obtained.Lastly,the optimal structure parameters of the proposed 5-DOF HPM are determined.Results show that the HPM with the optimized parameters has an enlarged orientation workspace,and the maximum angle of the reconfigurable base is decreased,which is conducive to improving the overall stiffness of HPM.展开更多
In order to satisfy the requirements of large workspace and high dexterity for processing equipment of oversized cylindrical boxes′spherical crown surfaces in the aerospace industry,a novel serial-parallel hybrid pro...In order to satisfy the requirements of large workspace and high dexterity for processing equipment of oversized cylindrical boxes′spherical crown surfaces in the aerospace industry,a novel serial-parallel hybrid processing robot mechanism is proposed.The degrees of freedom of the 5PUS-(2UR)PU parallel mechanism are obtained by using the screw theory.The inverse kinematics of the hybrid mechanism are analyzed and the velocity Jacobian matrix is established.Then,the constraints of the main factors influencing workspace of the mechanism are given,and the position and posture workspace are obtained.Next,the dexterity and stiffness performance of the mechanism is analyzed based on the Jacobian matrix.The virtual prototype is established,and the theoretical calculation and simulation analysis of the hybrid mechanism with arc curve as the processing trajectory are carried out by using Matlab and Adams software.The research results show that the mechanism can satisfy the requirements of large workspace and high dexterity of oversized cylindrical boxes′spherical crown surface processing,and has feasibility and practical application value.展开更多
大射电望远镜(LT)馈源柔索支撑系统可视为一种柔索并联机器人(WDPR).基于馈源柔索支撑系统的非线性力学模型,引入张力、球铰和索长约束条件,确定了WDPR的可达工作空间.进而,借助于有限元分析方法,利用静刚度阵的最小奇异值来评价该机器...大射电望远镜(LT)馈源柔索支撑系统可视为一种柔索并联机器人(WDPR).基于馈源柔索支撑系统的非线性力学模型,引入张力、球铰和索长约束条件,确定了WDPR的可达工作空间.进而,借助于有限元分析方法,利用静刚度阵的最小奇异值来评价该机器人的刚度性能.通过对LT50 m WDPR缩尺模型的空间运动数值仿真,绘制了三维可达工作空间图形及刚度曲面.分析结果表明,张力约束条件对LT可达工作空间影响最大,WDPR机器人与Stewart平台的刚度有明显差异.展开更多
基金the National Key Research and Development Program(2016YFB1001200)the National Natural Science Foundation of China(61572055 and 61633004).
文摘A wearable force-feedback glove is a promising way to enhance the immersive sensation when a user interacts with virtual objects in virtual reality scenarios.Design challenges for such a glove include allowing a large fingertip workspace,providing a desired force sensation when simulating both free-and constrained-space interactions,and ensuring a lightweight structure.In this paper,we present a forcefeedback glove using a pneumatically actuated mechanism mounted on the dorsal side of the user’s hand.By means of a triple kinematic paired link with a curved sliding slot,a hybrid cam-linkage mechanism is proposed to transmit the resistance from the pneumatic piston rod to the fingertip.In order to obtain a large normal component of the feedback force on the user’s fingertip,the profile of the sliding slot was synthesized through an analysis of the force equilibrium on the triple kinematic paired link.A prototype five-fingered glove with a mass of 245 g was developed,and a wearable force-measurement system was constructed to permit the quantitative evaluation of the interaction performance in both free and constrained space.The experimental results confirm that the glove can achieve an average resistance of less than 0.1 N in free-space simulation and a maximum fingertip force of 4 N in constrained-space simulation.The experiment further confirms that this glove permits the finger to move freely to simulate typical grasping gestures.
基金support provided by the Fundamental Research Funds for Central Universities,China(Grant No.2018JBZ007)the China Scholarship Council(Grant No.201807090006)the National Natural Science Foundation of China(Grant No.51675037).
文摘A novel hybrid perfusion manipulator(HPM)with five degrees of freedom(DOFs)is introduced by combining the 5PUS-PRPU(P,R,U and S represent prismatic,revolute,universal and spherical joint,respectively)parallel mechanism with the 5PRR reconfigurable base to enhance the perfusion efficiency of the large-scale spherical honeycomb thermal protection layer.This study mainly presents the dimensional synthesis of the proposed HPM.First,the inverse kinematics,including the analytic expression of the rotation angles of the U joint in the PUS limb,is obtained,and mobility analysis is conducted based on screw theory.The Jacobian matrix of 5PUS-PRPU is also determined with screw theory and used for the establishment of the objective function.Second,a global and comprehensive objective function(GCOF)is proposed to represent the Jacobian matrix’s condition number.With the genetic algorithm,dimensional synthesis is conducted by minimizing GCOF subject to the given variable constraints.The values of the designed variables corresponding to different configurations of the reconfigurable base are then obtained.Lastly,the optimal structure parameters of the proposed 5-DOF HPM are determined.Results show that the HPM with the optimized parameters has an enlarged orientation workspace,and the maximum angle of the reconfigurable base is decreased,which is conducive to improving the overall stiffness of HPM.
基金This work was supported by Fundamental Research Funds for the Central Universities(No.2018JBZ007).
文摘In order to satisfy the requirements of large workspace and high dexterity for processing equipment of oversized cylindrical boxes′spherical crown surfaces in the aerospace industry,a novel serial-parallel hybrid processing robot mechanism is proposed.The degrees of freedom of the 5PUS-(2UR)PU parallel mechanism are obtained by using the screw theory.The inverse kinematics of the hybrid mechanism are analyzed and the velocity Jacobian matrix is established.Then,the constraints of the main factors influencing workspace of the mechanism are given,and the position and posture workspace are obtained.Next,the dexterity and stiffness performance of the mechanism is analyzed based on the Jacobian matrix.The virtual prototype is established,and the theoretical calculation and simulation analysis of the hybrid mechanism with arc curve as the processing trajectory are carried out by using Matlab and Adams software.The research results show that the mechanism can satisfy the requirements of large workspace and high dexterity of oversized cylindrical boxes′spherical crown surface processing,and has feasibility and practical application value.
文摘大射电望远镜(LT)馈源柔索支撑系统可视为一种柔索并联机器人(WDPR).基于馈源柔索支撑系统的非线性力学模型,引入张力、球铰和索长约束条件,确定了WDPR的可达工作空间.进而,借助于有限元分析方法,利用静刚度阵的最小奇异值来评价该机器人的刚度性能.通过对LT50 m WDPR缩尺模型的空间运动数值仿真,绘制了三维可达工作空间图形及刚度曲面.分析结果表明,张力约束条件对LT可达工作空间影响最大,WDPR机器人与Stewart平台的刚度有明显差异.
