Parameter sensitivity analysis of a 5-DoF parallel manipulator

With the capability of determining main/subordinate parameters, parameter sensitivity analysis plays an important role in eliminating unimportant parameters and simplifying performance analysis and optimization model. Taking a 5 degree-of-freedom parallel manipulator (T5 PM) as an example, the effects of joint stiffness/compliance coefficients and parameters of cross section to the mass and stiffness performance are investigated through parameter sensitivity analysis based on response surface method and performance reliability. By selecting experimental strategy and implementing accuracy assessment, the response surface method is adopted to establish the mapping model of parameters and performance with high efficiency and accuracy. In the light of reliability sensitivity, the performance reliability to parameter mean value and variance are simultaneously considered by the global parameter sensitivity index, which is the principle for determining the impact extent of parameters. Moreover, how the parameters affect the targeted performance can be evaluated through RSAV, RSPC and RSNC defined by the performance reliability to the parameter mean value. After verifying the sensitivity analysis approach by SolidWorks simulation, the parameter discussion of T5 PM is carried out. 15 parameters are selected from the original 39 parameters and effects of these parameters are clearly demonstrated, which provide reference for the future optimization process.