Error kinematic modeling and calibration of the 3-DOF Gantry-Tau parallel kinematic machine

Abstract

This thesis presents the results of an investigation into modeling the kinematic errors of the Gantry-Tau Parallel Kinematic Manipulator. The calculations has been done onto the Gantry-Tau which has been designed in University Of Agder. Though, all the diminsions used in the simulation was tacken out from it. The Gantry-Tau consist of 3 parallel arms, 6 links, 12 joints, and 3 base linear actuators. Each arm contains one link that allows a translation movement. see Figure 1.1. In this thesis, the 3-DOF Inverse kinematic model is applied to the Gantry-Tau. The links is considered to be the error parameters. 3 error parameters account for errors in the 3 arm lengths. Deeply, 6 error parameters account for error in 6 links. Functionalities from two different types of measurement equipment; laser interferometers and linear encoders have been utilised to create the error calibration systems. Simulation measurment is replaced with laser interferometeres. The optimisation function for this implementation is built upon the basic geometric premises of the Gantry- Tau’s structure. The Complex Research method was used to optimise the error calibration. This method will mirror the worst result arround the centroid and produce the best result for calibration. In other words, the method tries to make the RMSE value equal to zero. The result is given as a function of the generation against the RMSE value.