基于Stewart并联结构六维力/力矩传感器在空间六维力的准确检测上具有广泛前景,设计低耦合、高精度、易于标定和使用的六维力/力矩传感器是其结构设计的关键问题。传统Stewart并联结构几何参数描述为6个相互耦合的变量,不利于实现设计参数与设计指标的解耦,而且非正交条件下的各向同性使得六维力/力矩传感器仍存在耦合,为此提出基于单叶双曲面定义并构造Stewart并联结构,将最小结构参数描述集元素数量减至3个,利用解析的静态数学模型推导满足传感器正向和逆向的力/力矩各向同性的条件,以得到二者相互制约的关系,给出解耦中心数学表达式。通过综合各个性能指标,提出了优化设计方法,给出了构造一类各向同性的Stewart并联结构六维力/力矩传感器的新方法,为该类传感器设计提供了新路线。
The six-dimensional force/torque sensor based on a Stewart parallel structure has great potential for application in the field of precise measurements of spatial forces, and it is a key issue in the structural design to develop a six-dimensional force/torque sensor with low coupling, high precision, ease of calibration and application. Traditional geometric parameters describing a Stewart parallel structure are six coupled variables, which are not beneficial to the decoupling of the design parameters to realize the design objective. In addition, the designed six-dimensional force/torque sensor is still coupled with isotropy in the condition of non-orthodology. This paper proposes to define and generate a Stewart parallel structure based on a circular hyperboloid of one sheet. By using this new definition, the geometric parameters describing a Stewart parallel structure is the minimal set only with three elements. The conditions of the forward isotropy and backward isotropy are derived based on the analytical static mathematical model, and the relationships are presented. The mathematical formulation of decoupled center is built. By compromising the performance indices, an optimal design routine is developed, and a new method is obtained to generate a class of isotropic six-dimensional force/torque sensor based on the Stewart parallel structure. The results provide a novel approach for the design of the six-dimensional force sensor.
[1] Huang Q T, Jiang H Z, Zhang S Y, et al. Spacecraft docking simulation using HIL simulator with Stewart platform[J]. Journal of Chinese Mechanical Engineering, 2005, 18(3): 415-418.
[2] Diddens D, Reynaerts D, van Brussel H. Design of a ring-shaped three-axis micro force/torque sensor[J]. Sensor and Actuators A: Physical, 1995, 46(1): 225-232.
[3] Kerr D R. Analysis, properties and design of a Stewart-platform transducer[J]. Journal of Mechanisms, Transmissions, Automation in Design, 1989, 111(1): 25-28.
[4] Nguyen C C, Antrazi S S, Zhou Z L, et al. Analysis and experimentation of a Stewart platform-based force/torque sensor[J]. International Journal of Robotics and Automation, 1992, 7(3): 133-140.
[5] Ferraresi C, Pastorelli S, Sorb M, et al. Static and dynamic behavior of a high stiffness Stewart platform-based force/torque sensor[J]. Journal of Robotic Systems, 1995, 12(12): 883-893.
[6] Dwarakanath T A, Dasgupta B, Mruthyunjaya T S. Design and development of a Stewart platform based force/torque sensor [J]. Mechatronics, 2001, 11(7): 793-809.
[7] Kang C G. Closed-form force sensing of a 6-axis force transducer based on the Stewart platform[J]. Sensors and Actuators A: Physical, 2001, 90(1):31-37.
[8] 高峰,王洪瑞,金振林. 一种具有弹性铰链的六维力与力矩传感器:中国,99102421.4. 1999-09-29. Gao Feng, Wang Hongrui, Jin Zhenlin. A six-axis force/torque sensor with elastic joints: China, 99102421.4. 1999-09-29. (in Chinese)
[9] 赵永生. 整体预紧平台式六维力传感器:中国,99102526.1. 2000-08-16. Zhao Yongsheng. Pre-stressed platform-based six-axis force sensor:China, 99102526.1. 2000-08-16. (in Chinese)
[10] 张晓辉, 高峰.Stewart结构六维力/力矩传感器力矩各向同性研究[J]. 计量学报, 2005, 26(1): 30-33. Zhang Xiaohui, Gao Feng. Study of torque isotropy of six-dimensional force sensor based on Stewart structure[J]. Acta Metrologica Sinica, 2005, 26(1): 30-33. (in Chinese)
[11] Uchiyama M, Nakamura Y, Hakomori K. Evaluation of the robot force sensor structure using singular value decomposition [J]. Journal of the Robotics Society of Japan, 1987, 5(1): 4-10.
[12] Wang H R, Gao F, Huang Z. Design of 6-axis force/torque sensor based on Stewart platform related to isotropy [J]. Chinese Journal of Mechanical Engineering, 1998, 11(3): 217-222.
[13] Jin Z L, Gao F. Optimal design of a 6-axis force transducer based on Stewart platform related to sensitivity isotropy [J]. Chinese Journal of Mechanical Engineering, 2003, 16(2): 146-148.
[14] 赵现朝. Stewart 结构六维力传感器设计理论与应用研究. 秦皇岛:燕山大学机械工程学院,2002. Zhao Xianchao. Design theory and application of the 6-axis F/T sensors based on Stewart platform structure. Qinhuangdao: School of Mechanical Engineering, Yanshan University, 2002. (in Chinese)
[15] 赵克定, 杨灏泉, 吴盛林, 等. 基于Stewart 平台的六维力/力矩传感器各向同性的解析研究[J]. 航空学报, 2002, 23(3): 241-244. Zhao Keding, Yang Haoquan, Wu Shenglin, et al. Analysis of isotropy for the six-axis force/torque based on Stewart platform[J]. Acta Aeronautica et Astronautica Sinica, 2002, 23(3): 241-244. (in Chinese)
[16] Bandyopadhyay S, Ghosal A. An algebraic formulation of static isotropy and design of statically isotropic 6-6 Stewart platform manipulators[J]. Mechanism and Machine Theory, 2009, 44(7): 1360-1370.
[17] 姚建涛, 侯雨雷, 毛海峡, 等. Stewart 结构六维力传感器各向同性的解析分析与优化设计[J]. 机械工程学报, 2009, 45(12): 22-28. Yao Jiantao, Hou Yulei, Mao Haixia, et al. Analytic analysis and optimal design of isotropy performance of six-dimensional force sensor based on Stewart platform[J]. Journal of Mechanical Engineering, 2009, 45(12): 22-28. (in Chinese)
[18] Yao J T, Hou Y L, Wang H, et al. Isotropic design of Stewart platform-based force sensor//Intelligent Robotics and Applications, Lecture Notes in Computer Science. Berlin Heidelberg: Springer, 2008, 5315: 723-732.
[19] Jiang H Z, Tong Z Z, He J F. Dynamic isotropy design of a class of Gough-Stewart parallel manipulators lying on a circular hyperboloid of one sheet[J]. Mechanism and Machine Theory, 2011, 46(3): 358-374.
[20] Jiang H Z, He J F, Tong Z Z. Characteristics analysis of joint space inverse mass matrix for the optimal design of a 6-DOF parallel manipulator[J]. Mechanism and Machine Theory, 2010, 45(5): 710-729.
[21] Jafari F, McInroy J E. Orthogonal Gough-Stewart platforms for micromanipulation[J]. IEEE Transactions on Robotics and Automation, 2003, 19(1): 595-603.
[22] Geng Z J, Haynes L S. Six degree-of-freedom active vibration control using the Stewart platforms[J]. IEEE Transactions on Control Systems Technology, 1994, 2(1): 45-53.
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