In most of references available, the effects of cable vibration on positioning precision of a cable-driven parallel manipulator are not adequately considered. Here, a dynamic model for a cable-driven parallel manipulator in slow motion was presented. In this model the motion of each cable was decomposed into two components, namely, stable motion and small vibration. The desired motion of the manipulator could be realized using the stable motion of the cables, and the motion of a cable shifting from its stable position could be described with a small vibration. Controllers were designed for both motions. The controller for stable motion was devised to guarantee the manipulator to move along desired trajectories while the one devised for small vibration was used to suppress vibrations of the cables in motion, these vibrations were not expected. A numerical example was presented to validate the dynamic model and the control algorithm proposed.%现有索牵引并联机器人研究中,大多没有考虑柔索振动对系统运行精度的影响.为此,提出一种适用于慢速运动的索牵引并联机器人动力学模型,模型中将柔索的运动分解为稳态运动与小幅振动两部分.系统的期望运动可由柔索的稳态运动来实现,柔索偏离稳态位置的运动可由对应的小幅振动来描述.针对稳态运动和小幅振动分别设计了相应的控制器,稳态运动的控制器保证系统可按期望的轨迹运行,小幅振动的控制器则用来抑制柔索在运动过程中出现的振动,这种振动是不希望出现的.最后,给出了一个数值算例来验证本文动力学模型及控制算法的有效性.
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