Dynamic Analysis Of Flexible Manipulator With Clearance Considering Parameter Uncertainty

The space manipulator is a highly nonlinear,strongly coupled,time-varying multi-body dynamic system.The space manipulator mainly works in outer space and is not affected by the earth's atmospheric environment and gravity.It is convenient to move in a large space and has convenient operation.It has become the main equipment for space installation and maintenance.Under the influence of the extreme temperature difference in space,the space manipulator causes some characteristic parameters of the space manipulator itself to change within a certain interval,such as the elastic modulus,the position of the center of mass,the length of the arm,and the density,etc.;In the actual movement process,the movement deformation of the space flexible manipulator is the coupling of its large-scale rotation and small deformation vibration;at the same time,there are errors in the process of manufacturing and assembly of the space flexible manipulator,making the joint of the space flexible manipulator There is a motion gap at the joint,and the motion of the space manipulator becomes more complicated under the influence of two factors,and its dynamic behavior becomes more difficult to analyze.This paper mainly focuses on the uncertainty modeling of the flexible manipulator with space in the gap and the uncertain dynamic characteristics during the motion.This paper combines flexible multi-body dynamics and related theories of analytical mechanics,and uses the Euler-Bernoulli beam model to describe the vibration and deformation of the flexible manipulator during the movement of the bending deformation,axial deformation and shear deformation;At the same time,considering the motion pair gap existing in the flexible manipulator system,a three-state collision gap model that conforms to the actual motion process is established,and the state function is used to describe the collision and separation process of the motion pair gap;the Lagrange equation is used to ignore the system coupling terms and Non-linear term,the deterministic model of rigid-flexible manipulator with clearance is derived.The deterministic model of the rigid-flexible manipulator with gaps in this paper overcomes the problem that the gap of the motion pair cannot be described in the traditional model,and provides a theoretical basis for accurately describing the motion process of the space manipulator.This paper analyzes the uncertainty factors that may exist in the system under the space environment,introduces the interval uncertainty model,and establishes the interval uncertainty model of the rigid-flexible manipulator with clearance based on the deterministic model of the rigid-flexible manipulator with clearance.The interval algorithm is used to solve the rules,and the approximate results of the Chebyshev and Taylor expansion functions are analyzed by comparison.The Chebyshev expansion function is selected as the interval algorithm in this paper.At the same time,based on the uncertain dynamic model of the rigid-flexible manipulator,using Chebyshev expansion function,and based on the established interval algorithm process,the material density of the flexible manipulator,the length of the flexible manipulator,the width of the joint gap,the contact collision stiffness coefficient and other intervals are analyzed.The uncertain dynamic behavior of the flexible manipulator under the influence of parameters;at the same time,according to the system sensitivity analysis method,combined with the Chebyshev interval algorithm,the Chebyshev method for solving the system sensitivity of the interval uncertainty is established,and the length of the flexible manipulator and the joint gap width are analyzed.The influence of uncertain flexible manipulator system sensitivity provides theoretical and data support for the subsequent reliability analysis and optimization design of space flexible manipulator...