A Rigidity and Flexibility Coupled Reliability Calculation Method for the Type 6-6 Stewart Parallel Mechanism

Abstract

Type 6-6 Stewart Parallel Mechanisms have been used widely in industries nowadays. Because of the influence of inevitable flexible deformations of each structural part, the loss of mechanism motion accuracies are obvious. It reported an effective rigidity and flexibility coupled reliability calculation method for this kind of mechanism. Firstly, it built a parameterized 3-D virtual model of this mechanism in ADAMS, and then used user defined function (a function in VC++ software) to simulate the stochastic error distributions; through this method, a Monte Carlo parametric model was built, and this was a basis for subsequent reliability calculation. Secondly, it programmed a reliability calculation system for this mechanism and performed multiple dynamic simulations to obtain the mechanism reliability data. This method took the influence of key parts flexible deformation on mechanism motion accuracy into account, and included simplicity (no need to solve complex mathematic model) and high accuracy which make it highly promising for application in mechanism design.