绳驱动拟人臂机器人的动力学建模及张力分析

与传统的机械臂相比,绳驱动拟人臂机器人采用串并混联的结构形式,模拟了人手臂肌肉的并联驱动方式,但是,绳索的引入也增加了动力学分析的难度.将绳驱动拟人臂机器人视为基座、大臂、小臂和末端四连杆串联机构,采用迭代牛顿-欧拉法建立动力学方程的递推形式,考虑绳驱动的冗余特性和绳索的单方向受力性,提出基于动态最小预紧力的张力分配算法,求解出各绳索的驱动力.与未进行张力分配的方法及基于静态最小预紧力的方法相比,所提出的算法可使各绳索驱动力根据动态最小预紧力进行实时调节,满足了不同工作条件下机构的刚度要求.

Dynamics modeling and tension analysis for a cable-driven humanoid-arm robot

Compared to the traditional robotic arm, the cable-driven humanoid-arm robot (CDHAR) similar to human muscles parallel drive mode is the hybrid structure of serial-parallel. However, the introduction of cables also increases the difficulty in dynamic analysis. CDHAR can be seen as a four-link serial mechanism including base, upper arm, forearm and end-effector, iteration Newton-Euler method was adopted to establish the recursive form of dynamics equation. Taking into account the redundant actuation and single-direction force for the cable, tension distribution algorithm based on the dynamic minimum pre-tightening force was proposed to calculate driving force of each cable. Compared to the method without conducting tension distribution or based on the static minimum pre-tightening force, the proposed algorithm can make the driving force of each cable real-time adjust by the dynamic minimum pre-tightening force and meet the rigidity requirement in different running condition.