In current research on soft grippers,pneumatically actuated soft grippers are generally fabricated using fully soft materials,which have the advantage of flexibility as well as the disadvantages of a small gripping fo...In current research on soft grippers,pneumatically actuated soft grippers are generally fabricated using fully soft materials,which have the advantage of flexibility as well as the disadvantages of a small gripping force and slow response speed.To improve these characteristics,a novel pneumatic soft gripper with a jointed endoskeleton structure(E-Gripper)is developed,in which the muscle actuating function has been separated from the force bearing function.The soft action of an E-Gripper finger is performed by some air chambers surrounded by multilayer rubber embedded in the restraining fiber.The gripping force is borne and transferred by the rigid endoskeleton within the E-Gripper finger Thus,the gripping force and action response speed can be increased while the flexibility is maintained.Through experiments,the bending angle of each finger segment,response time,and gripping force of the E-Gripper have been measured,which provides a basis for designing and controlling the soft gripper The test results have shown that the maximum gripping force of the E-Gripper can be 35 N,which is three times greater than that of a fully soft gripper(FS-Gripper)of the same size.At the maximum charging pressure of 150 kPa,the response time is1.123 s faster than that of the FS-Gripper.The research results indicate that the flexibility of a pneumatic soft gripper is not only maintained in the case of the E-Gripper,but its gripping force is also obviously increased,and the response time is reduced.The E-Gripper thus shows great potential for future development and applications.展开更多
This paper presents a vacuum gripper （as an actuator of an intelligent micromanipulator） for micro objects （with a diameter of 100 - 300μm） assembly tasks. The gripper is composed of a vacuum unit and a control u...This paper presents a vacuum gripper （as an actuator of an intelligent micromanipulator） for micro objects （with a diameter of 100 - 300μm） assembly tasks. The gripper is composed of a vacuum unit and a control unit. The vacuum unit with a proportional valve and a pressure sensor, and the control unit with a PC ＋ MCU two-layered control architecture are designed. The mechanical structure, workflow and major programs of the micro-gripper are presented. This paper discusses the major components of the adhesion force acting on micro objects. Some equations of the operation conditions m three phases of pick, hold and place are derived by mechanics analysis. The pneumatic system＇s pressure loss is inevitable. There are some formulas for calculating the amount of the pressure loss, but parameters in formulas are diffficult to be quantified and evaluated. To control the working pressure accurately, a pressure controller based on fuzzy logic is designed. With MATLAB＇s fuzzy logic toolbox, simulation experiments are performed to validate the performance of the fuzzy PD controller. The gripper is characterized by a steady and reliable performance and a simple structure, and it is suitable for handling micro objects with a sub-millimeter size.展开更多
A study about the action control of a dexterous mechanical gripper based on stereo-vision system was proposed. The vision-based system was used to replace the data-glove for gesture measurement. The stereo vision theo...A study about the action control of a dexterous mechanical gripper based on stereo-vision system was proposed. The vision-based system was used to replace the data-glove for gesture measurement. The stereo vision theory was applied to calculate the 3D information of the hand gesture. The information was used to generate the grasping action parameters of a 3-finger dexterous mechanical gripper. Combined with a force feedback device, a closed control loop could be constructed. The test for the precision of the algorithms and action control simulation result were shown in the paper.展开更多
The characteristics of a kind of comb-drive electrostatic actuated micro-gripper are tested. The test platform using a microscope-CCD-computer, the state information of the micro-gripper obtained by data acquisition a...The characteristics of a kind of comb-drive electrostatic actuated micro-gripper are tested. The test platform using a microscope-CCD-computer, the state information of the micro-gripper obtained by data acquisition and image processing, voltage-displacement characteristic curve is obtained and the mathematical equation is established. The analysis of the characteristic equation has shown the consistency and rationality of the theoretical design and the experimental results. The main factors that cause the difference between the theoretical design and the actual test performance are analyzed, and the design method and experimental results is obtained for the micro-gripper in the field of micro-assembly.展开更多
A system using microgripper for gluing and adhesive bonding in automatic microassembly was designed, implemented, and tested. The development of system is guided by axiomatic design principle. With a compliant PU micr...A system using microgripper for gluing and adhesive bonding in automatic microassembly was designed, implemented, and tested. The development of system is guided by axiomatic design principle. With a compliant PU microgripper, regional-edge-statistics (RES) algorithm, and PD controller, a visual-servoing system was implemented for gripping micro object, gluing adhesive, and operating adhesive bonding. The RES algorithm estimated and tracked a gripper’s centroid to implement a visual-servoing control in the microassembly operation. The main specifications of the system are: gripping range of 60~80μm, working space of 7mm×5.74mm×15mm, system bandwidth of 15Hz. In the performance test, a copper rod with diameter 60μm was automatically gripped and transported for transferring glue and bonding. The 60μm copper rod was dipped into a glue container and moved, pressed and bonding to a copper rod of 380μm. The amount of binding glue was estimated about 5.7nl.展开更多
提出了一种单顶点多折痕(single-vertex and multi-crease,SVMC)的双稳态折纸软体夹持器,具有结构简单、成本低、变形速度快、承载能力强等优点,有效改善了传统模型响应速度慢、夹持效率低等缺陷。该模型基于水弹结构建立,利用球面三角...提出了一种单顶点多折痕(single-vertex and multi-crease,SVMC)的双稳态折纸软体夹持器,具有结构简单、成本低、变形速度快、承载能力强等优点,有效改善了传统模型响应速度慢、夹持效率低等缺陷。该模型基于水弹结构建立,利用球面三角形余弦定理分析了折痕角度之间的关系并建立运动学方程;同时借助扭簧模型探究变形过程中的势能转化规律。分析了折痕长度与初始角度对能力存储和释放过程的影响,并以此为基础优化了模型结构参数。实验结果表明,当受到2.6 N的外部触发力时,软体夹持器可在61 ms内完成从外展姿态到内缩状态的变化,实现对目标表面的快速包络;同时,借助线绳驱动提供更大的夹紧力,完成对目标的高效稳定抓取。此模型可广泛应用于复杂轮廓目标抓取和快速食品分拣领域。展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51305202)Jiangsu Provincial Natural Science Foundation of China(Grant No.BK20130764)
文摘In current research on soft grippers,pneumatically actuated soft grippers are generally fabricated using fully soft materials,which have the advantage of flexibility as well as the disadvantages of a small gripping force and slow response speed.To improve these characteristics,a novel pneumatic soft gripper with a jointed endoskeleton structure(E-Gripper)is developed,in which the muscle actuating function has been separated from the force bearing function.The soft action of an E-Gripper finger is performed by some air chambers surrounded by multilayer rubber embedded in the restraining fiber.The gripping force is borne and transferred by the rigid endoskeleton within the E-Gripper finger Thus,the gripping force and action response speed can be increased while the flexibility is maintained.Through experiments,the bending angle of each finger segment,response time,and gripping force of the E-Gripper have been measured,which provides a basis for designing and controlling the soft gripper The test results have shown that the maximum gripping force of the E-Gripper can be 35 N,which is three times greater than that of a fully soft gripper(FS-Gripper)of the same size.At the maximum charging pressure of 150 kPa,the response time is1.123 s faster than that of the FS-Gripper.The research results indicate that the flexibility of a pneumatic soft gripper is not only maintained in the case of the E-Gripper,but its gripping force is also obviously increased,and the response time is reduced.The E-Gripper thus shows great potential for future development and applications.
基金This work was supported bythe National Natural Science Foundation of China (No .60275013) the Natural High Technology Researchand DevelopementProgramof China(No .2004AA844120) .
文摘This paper presents a vacuum gripper （as an actuator of an intelligent micromanipulator） for micro objects （with a diameter of 100 - 300μm） assembly tasks. The gripper is composed of a vacuum unit and a control unit. The vacuum unit with a proportional valve and a pressure sensor, and the control unit with a PC ＋ MCU two-layered control architecture are designed. The mechanical structure, workflow and major programs of the micro-gripper are presented. This paper discusses the major components of the adhesion force acting on micro objects. Some equations of the operation conditions m three phases of pick, hold and place are derived by mechanics analysis. The pneumatic system＇s pressure loss is inevitable. There are some formulas for calculating the amount of the pressure loss, but parameters in formulas are diffficult to be quantified and evaluated. To control the working pressure accurately, a pressure controller based on fuzzy logic is designed. With MATLAB＇s fuzzy logic toolbox, simulation experiments are performed to validate the performance of the fuzzy PD controller. The gripper is characterized by a steady and reliable performance and a simple structure, and it is suitable for handling micro objects with a sub-millimeter size.
文摘A study about the action control of a dexterous mechanical gripper based on stereo-vision system was proposed. The vision-based system was used to replace the data-glove for gesture measurement. The stereo vision theory was applied to calculate the 3D information of the hand gesture. The information was used to generate the grasping action parameters of a 3-finger dexterous mechanical gripper. Combined with a force feedback device, a closed control loop could be constructed. The test for the precision of the algorithms and action control simulation result were shown in the paper.
文摘The characteristics of a kind of comb-drive electrostatic actuated micro-gripper are tested. The test platform using a microscope-CCD-computer, the state information of the micro-gripper obtained by data acquisition and image processing, voltage-displacement characteristic curve is obtained and the mathematical equation is established. The analysis of the characteristic equation has shown the consistency and rationality of the theoretical design and the experimental results. The main factors that cause the difference between the theoretical design and the actual test performance are analyzed, and the design method and experimental results is obtained for the micro-gripper in the field of micro-assembly.
文摘A system using microgripper for gluing and adhesive bonding in automatic microassembly was designed, implemented, and tested. The development of system is guided by axiomatic design principle. With a compliant PU microgripper, regional-edge-statistics (RES) algorithm, and PD controller, a visual-servoing system was implemented for gripping micro object, gluing adhesive, and operating adhesive bonding. The RES algorithm estimated and tracked a gripper’s centroid to implement a visual-servoing control in the microassembly operation. The main specifications of the system are: gripping range of 60~80μm, working space of 7mm×5.74mm×15mm, system bandwidth of 15Hz. In the performance test, a copper rod with diameter 60μm was automatically gripped and transported for transferring glue and bonding. The 60μm copper rod was dipped into a glue container and moved, pressed and bonding to a copper rod of 380μm. The amount of binding glue was estimated about 5.7nl.
文摘提出了一种单顶点多折痕(single-vertex and multi-crease,SVMC)的双稳态折纸软体夹持器,具有结构简单、成本低、变形速度快、承载能力强等优点,有效改善了传统模型响应速度慢、夹持效率低等缺陷。该模型基于水弹结构建立,利用球面三角形余弦定理分析了折痕角度之间的关系并建立运动学方程;同时借助扭簧模型探究变形过程中的势能转化规律。分析了折痕长度与初始角度对能力存储和释放过程的影响,并以此为基础优化了模型结构参数。实验结果表明,当受到2.6 N的外部触发力时,软体夹持器可在61 ms内完成从外展姿态到内缩状态的变化,实现对目标表面的快速包络;同时,借助线绳驱动提供更大的夹紧力,完成对目标的高效稳定抓取。此模型可广泛应用于复杂轮廓目标抓取和快速食品分拣领域。
