Method to avoid dynamic singularity for flexible manipulators
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摘要: 对柔性机器人避动力奇异的方法进行了研究,得出当机器人第i阶模态频率与模态激振力某阶频率相等,且模态激振力比较大时,机器人就会出现动力奇异问题的结论;分析了机器人的结构参数和运动参数是影响其固有频率的因素,提出了在不改变机器人预定工作任务的情况下,对已有的机器人可以通过在其柔性臂上附加一质量块以调节机器人的固有频率,从而避免动力奇异问题的发生;同时给出了附加质量块的规划策略,并以一末杆为柔杆的空间三杆机器人为例,验证了所提方法的有效性.该方法也适用于其它一般机械系统.Abstract: When the natural frequency of the flexible manipulators is equal to the frequency of the mode force and the mode force is stronger, the dynamic singularity will happen. The structure parameter and kinetic parameter of the flexible manipulator are the factors which influence the natural frequency of the flexible manipulator. A method to avoid the dynamic singularity was given on the condition that the predetermined task is not changed. The method is that a mass can be attached to the existed flexible manipulator to change the frequency of the flexible manipulator, so as to avoid the dynamic singularity. A method to plan the mass and the position where the mass attached to the flexible manipulator was given. A space manipulator with three arms ( the last one is flexible) was simulated, and the method was verified to be effective. This method can also used in other mechanism system.
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Key words:
- frequency /
- dynamic /
- mass /
- flexible manipulator
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[1] Midha A, Karam D, Thompson B S. The elastic slider-crank mechanism:a study of the intrinsic configuration-dependent modal properties[J] ASME Design Technical Conf, 1992,47:337~346 [2] Liou F Y, Liu J D. A parametric study on the design of multi-body systems with elastic members[J] Mech Mach Theory, 1994,29(8):1219~1231 [3] Fung E H K,Yau D T W. Vibration frequencies of a rotating flexible arm carrying a moving mass[J] Journal of Sound and Vibration, 2001, 241(5):859~878 [4] 余跃庆. 弹性连杆机构参量振动频率特性分析[J] 机械工程学报, 1996, 32(2):47~52 Yu Yueqing. Parametric vibrational responses of elastic linkage mechanisms[J] Chinese Journal of Mechanical Engineering, 1996,32(2):47~52(in Chinese) [5] 超, 宋量量, 李 然,等. 120kg点焊机器人试验模态分析[J] 机械工程学报, 2001,37(1):38~42 Yun Chao, Song Liangliang, Li Ran, et al. Experimental modal analysis of 120kg spot welding robots[J] Chinese Journal of Mechanical Engineering, 2001,37(1):38~42(in Chinese) [6] 余跃庆,李 哲. 现代机械动力学[M] 京:北京工业大学出版社,1998 Yu Y Q,Li Z. Dynamics of mode mechanism[M] Beijing:Beijing University of Technology Press,1998(in Chinese) [7] 高志慧, 超, 边宇枢. 柔性机器人动力奇异问题的研究[J] 机械工程学报, 2004,40(11):64~69 Gao Zhihui, Yun Chao, Bian Yushu. Study on the dynamic singularity of the flexible manipulators[J] Chinese Journal of Mechanical Engineering, 2004,40(11):64~69(in Chinese)
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