可控变胞式码垛机器人非线性动态可靠性分析  

Nonlinear Dynamic Reliability Analysis for a Controllable Metamorphic Palletizing Robot

作　　者：王汝贵[1] 陈辉庆 董奕辰 WANG Rugui;CHEN Huiqing;DONG Yichen(College of Mechanical Engineering,Guangxi University,Nanning 530004;College of Mechanical and Control Engineering,Guilin University of Technology,Guilin 541006)

机构地区：[1]广西大学机械工程学院,南宁530004 [2]桂林理工大学机械与控制工程学院,桂林510006

出　　处：《机械工程学报》2023年第11期189-200,共12页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(51865001)。

摘　　要：变胞机构具有多构态的优点,在构态变换时会不可避免地产生内冲击力,严重时会发生共振,其动态可靠性问题是确保其在工程应用中实现多构态正常运行的关键。以面向工件搬运任务的可控变胞式码垛机器人为研究对象,在运用有限元法建立该机器人工作过程的非线性动力学模型的基础上,运用改进的L-P法得出该模型的共振频率,考虑了多种失效模式、多种不确定变量和非线振动因素的影响,提出了非线性动态可靠性的分析方法。在实例中以输入端角度偏差值、输出端负载为不确定变量进行可靠性分析,得出了机器人构态变换后的可靠度变化,将该计算结果与基于神经网络的蒙特卡洛法的计算结果以及实验数据得出的结果进行了对比,偏差均较小,说明该方法具有一定的准确性。进一步,考虑内冲击力频率为不确定变量,在含有共振频率的频率区间内得出了避免发生失效所对应的不确定变量的范围。研究工作为面向任务的变胞机构的实际应用提供了可靠性理论参考。Metamorphic mechanism has the advantages of multiple configurations.It will inevitably suffer internal impact during configuration transformation,and resonance will occur seriously.Its dynamic reliability is the key to ensure the normal operation of multiple configurations in engineering application.A controllable metamorphic palletizing robot for workpiece handling is taken as the research object.On the basis of establishing the elastic dynamic model of the working process of the robot by using the finite element method,the resonance frequency of the model is obtained by the improved L-P method.Multiple failure modes,uncertain variables and nonlinear vibration factors are considered.An analysis method for nonlinear dynamic reliability is proposed.In case study,the input angle deviations and output load are taken as uncertain variables,and the reliability variation after the configuration transformation of the robot is calculated.The calculated results are compared with those obtained by the neural network-based Monte-Carlo method and experimental data,the deviations are small.It shows that the proposed method has certain accuracy.Furthermore,considering the frequency of internal impact force as an uncertain variable,the range of uncertain variables corresponding to avoiding failure is obtained in the frequency range containing resonance.This work provides a reliability theoretical reference for the practical application of task-oriented metamorphic mechanisms.

关 键 词：变胞机构 码垛机器人 动态可靠性 不确定变量 非线性 

分 类 号：TH113[机械工程—机械设计及理论]