摘要
高速并联机械手的驱动系统一般采用中小功率交流伺服电动机与精密减速箱配套使用的模式。减速箱在驱动系统中用于降低输出转速、提高驱动力矩,其减速比直接影响高速并联机械手的加减速能力和拾放操作速度。基于此,提出一种新型S形速度曲线方案。采用该方案进行轨迹规划,能确保机械手加速度的连续,有利于降低机械手的残余振动。提出一种以平均拾放操作时间最短为目标,以交流伺服电动机需满足的运行原则为约束条件,对驱动系统减速比进行优化配置的方法。以2自由度并联机构为例,在逆动力学建模、轨迹规划的基础上,对其最优减速比进行有约束非线性规划。数值仿真结果证明了该方法的有效性。采用该优化方法可以充分发挥交流伺服电动机的性能,从而有利于降低机械手驱动系统的成本。这种方法也可应用于其他类型的高速并联机械手。
The small-medium powered AC servomotors and the matched precision gearboxes, being able to amplify output torque and reduce output speed, are widely used in the driving system of the high speed parallel manipulators. The reduction ratio of the driving system plays a very important role in the accelerating capacity, decelerating capacity and operation speed for a parallel manipulator. A new S-curve speed profile, which can help to plan the trajectory of the end-effecter of the manipulator for minimum residual vibration, is introduced. An optimal reduction ratio selection method for the driving system, which takes the applying principles of the AC servomotor as constraint conditions and aims at the minimal operation time, is proposed. A parallel manipulator with 2 degrees of freedom is taken as example. Based on inverse dynamics modeling and trajectory planning, a non-linear program with some constraints is carried out. The simulation results illustrate the effectiveness of the optimization method. The optimization method can also be used to make full use of the advantages of the AC servomotor and consequently reduce the cost of manipulator. The optimization method can also be applied in designing other parallel manipulators.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2009年第2期255-261,共7页
Journal of Mechanical Engineering
基金
国家自然科学基金(50775073)
粤港关键领域重点突破招标(20061682)
广东省教育部产学研结合(2006D90304001)资助项目
关键词
并联机械手
减速比
优化配置
Parallel manipulator Reduction ratio Optimal selection