Research On Transmission Accuracy Of RV Reducer For Robot Based On Robust Design

RV(Rotate Vector)reducer is a high-performance precision transmission device,which has the characteristics of small size,compact structure,large transmission ratio,strong bearing capacity and high precision.It is widely used in the rotary arm drive device of industrial robots.In this paper,RV reducer transmission accuracy of two indicators : transmission angle error and return error as the research object,the RV-110 E reducer is selected as the prototype.The influence of machining error and assembly error of main components in reducer on transmission accuracy is studied,and the mathematical model of transmission accuracy index is established.Based on the robust design idea,the evaluation method and design criterion of transmission accuracy robustness of RV reducer under uncertainty are investigated to improve the stability of RV reducer in the design stage.The main work is as follows :(1)The basic structure and transmission principle of RV reducer for robot are briefly introduced,and the transmission ratio of RV reducer under different working modes is calculated by using the conversion mechanism method.According to the basic theory of mechanism error,the characteristic analysis of RV reducer return error and large and small cycle transmission angle error is carried out.The mathematical model of RV reducer return error caused by geometric error of components is discussed.At the same time,the influence of geometric error of main components on mechanism transmission error is calculated,and the transmission error is measured by angular displacement error.(2)The calculation program is written for the mathematical model of the return error of RV reducer,and the sensitivity analysis of the influencing factors is carried out.Based on the idea of robust design,the test results are analyzed by various methods using orthogonal test,and the optimal parameter combination of influencing factors is determined,which effectively reduces the return error and effectively improves the reliability of RV reducer in the design stage.(3)Under the framework of evidence theory,the uncertainty quantification and robustness analysis of large and small cycle transmission angle errors of RV reducer are carried out,and the random uncertainty and cognitive uncertainty factors are uniformly characterized.The robustness evaluation method of transmission angle error based on evidence theory is proposed,and the corresponding robust optimization design criteria for transmission error is proposed,which makes the robustness evaluation and control of RV reducer more scientific and reasonable.(4)Based on the multi-body dynamics simulation software Recurdyn,the virtual prototype model of RV-110 E reducer is established.The angle and speed curves of each component under different working conditions can be obtained.According to the detection principle of transmission angle error and return error of RV reducer,the transmission error and return error of the virtual prototype are calculated according to the detection principle formula after extracting the data.The design and calculation process of the above chapters are verified.