【作者】 牛帅；

【导师】 吴伟国；

【作者基本信息】 哈尔滨工业大学 ， 机械设计及理论， 2010， 硕士

【摘要】 模块化机械臂的基本组成元件是关节单元,可以根据实际情况组合出不同规格的机械臂,能够适应多变的工作环境和任务要求,近年来已成为机器人研究的一个新的热点问题,引起了国内外众多学者的关注。本文基于构建的关节库,主要研究内容包括机械臂臂长优化、轨迹规划以及实例仿真等部分。首先,本文提出了三种不同的运动学性能指标,三种性能指标具有不同的应用范围,结合模块化机械臂的特点,分别优化了两自由度、三自由度以及六自由度机械臂的臂长,获得机械臂杆长的最佳比例关系。然后,本文根据模块化原则设计了一种关节单元,构建了包含48个关节单元的单元库,并对构件进行了速度分析,用Newton-Euler法推导出了机械臂关节力矩递推公式。根据机械臂的动力学特性,提出了三种动力学性能评价指标,并在此基础上构造了模块化机械臂多目标优化模型。此外,本文提出了模块化机械臂运动学问题的新方法,在此基础上利用杆件参数优化结果,对4-DOF模块化机械臂进行了直线轨迹规划,对于6-DOF机械臂,采用4-3-4多项式轨迹在关节空间进行了轨迹规划,绘出了轨迹曲线,生成了轨迹样本。最后,在构建的关节单元库的基础上,本文分别利用遗传算法和一般优化算法,遴选出6-DOF和4-DOF模块化机械臂的关节单元组合,运用ADAMS进行虚拟样机仿真,经过验证,两组关节单元组合均满足了约束条件。从仿真结果可以得出结论,本文所研究的机械臂关节单元优化组合方法可行。更多还原

【Abstract】 Joint module unit is the basic element of modular manipulator, with which it could assembly to a varity of manipulators that could be applied to different working environm-ent. Modular manipulator has also became a hot issue in the domain of robotics and caught the eye of the researchers around the world in recent years. In this paper, it concentrate on the configuration optimization, trajectory planning and dynamic simulati-on of the manipulators.Firstly, Three kinds of kinematics performance Indices are proposed in this paper, which has its own application scope. According to the fetures in configurations of the modular manipulators, the manipulators ,which have two,three and six degrees of freedom respectively,are optimized to acchive the optimum length ritio between the upper arm and fore arm.What’s more, a structure of Joint module unit is also devised using Modular Design principle in this paper, and Joint module library is built on the basis of forty-eight joint modules. After velocity analysis of joints, the recursion formulas of torques in every joint are deduced using Neton-Euler method. According to the dynamics performance of the manipulator, A multi-objective optimization model is constructed with three dynamics performance functions.Furthermore, a new method is proposed to solve the kinematics of modular manipu-lator. With the optimization results of configuration, the trajectory of a 4-DOF manipulat-or is accomplished by linear trajectory planning, and it also plans a 6-DOF manipulator’s trajectory using 4-3-4 polynomial. The specimen of the trajectory is obtained and the cur-ve of the path in every joint is also plotted by the planning programme.At last, two series of joint modules are selected from the joint module unit library using genetic algorithm and common algorithm respectively, which could assembly to a 6-DOF and 4-DOF manipulators. The three-dimention models are transferred to ADAMS software for dynamics simulation verify that the peak value of the torque in every joint has been satisfied the constraints in optimization model. It is concluded that the optimization method for modular manipulator in this paper is feasible.更多还原