Kinematic modeling and parameter identification for a heavy gantry-type automated fiber placement machine considering gravity deformation

Abstract

Automated fiber placement machine is the key equipment for low-cost and automated manufacturing of high-performance carbon composite materials. In order to meet the required position accuracy of fiber placement, this paper focuses on the kinematic modeling and parameter identification of the automated fiber placement machine. A kinematic model taking account of geometric deviations is established firstly. Since joint interfaces are the main origin of gravity deformation in a machine tool, an elastic beam deformation model is introduced to represent the joint interface, and then the former kinematic model is modified by analytical expressions of the gravity deformation for each joint interface. Based on the measurement data and the Levenberg-Marquardt optimization method, the parameter identification of the kinematic model is realized, and main issues such as measurement data selection, objective function definition are discussed. Finally, a kinematic calibration experiment is performed, and the experimental results verify the feasibility and validity of the modeling method. The position errors in Z direction of the automated fiber placement machine are effectively reduced by over 80%, which suggests that the proposed method reduces the effect of the gravity deformation and improves the accuracy of the automated fiber placement machine.