Extended Procedure for Stiffness Modeling Based on the Matrix Structure Analysis

摘要

For handling tasks requiring high accuracy and high dynamics, good stiffness properties of the manipulator are crucial and need to be taken into account in the design phase. Known methods to calculate the stiffness properties of amechanical structure are the Finite Element Analysis, the Virtual Joint Method and the Matrix Structure Analysis. These methods trade off the complexity and computational costs against the accuracy of the results. This paper presents an extended procedure to model and analyze the stiffness properties of mechanical structures based on the Matrix Structure Analysis. The stiffness matrix of the structure is assembled automatically, following the described algorithm. The deformation of the structure under external load can then be calculated directly. In this procedure, complex links and joints with force dependent (non-linear) stiffness properties can be taken into account. This extended procedure is validated by measurements on a robotic arm.