Simulation and experimental implementation of a generalized predictive control for an orthoglide robot based on the dynamic modeling

Author(s)

Fabian Andres Lara Molina

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Mecânica
• Defense date: 2012-02-23

Examining board members

João Maurício Rosário; Edson Roberto de Pieri; Antonio Batocchio; Tarcisio Antonio Hess Coelho; Marconi Kolm Madrid

• Advisor: Dider Dumur; João Maurício Rosário

Abstract

This thesis addresses the development and application of a controller based on generalized predictive control to track a desired trajectory using parallel robots. The main purpose of this thesis is to improve the dynamical behavior with an advanced controller which considers the proper characteristics of the parallel robot such as no linear dynamics, parameters uncertainties and external disturbances. This work is divided into four parts. A first part formulates the complete dynamical model of the parallel robot, considering the geometrical, kinematic and dynamic modelling. Then, the joint space control is performed for the parallel robot using the computed torque controller in the RST form and the robustified generalized predictive control via Youla parameterization. A third part shows the simulation of the dynamic of the robot with the controllers in MATLAB/Simulink to establish a comparison between controllers. Finally, the controllers are implemented in the prototype and some experiments are performed on the Orthoglide robot at the laboratory of robotics, IRCCyN, Ecole Centrale de Nantes to assess the dynamic performance of the controllers. The experimental results show that the robustification of the generalized predictive control against parametric uncertainties including time domain constraints improves the dynamical behavior of the parallel robots. The experimental results shows that the the robustified generalized predictive control enhances the dynamic performance of is in terms of: tracking accuracy of trajectories used in milling process; robustness to parameters variation such as payload changing (on the end effector), therefore, a better regulation is obtained; and finally, attenuation of noise due to sensor measurement in control. Additionally, the robustification of the generalized predictive control applied on the Orthoglide robot improves the dynamical behavior compared to controllers widely used in parallel robots such as computed torque control with and equivalent computational cost (AU)

• FAPESP's process: 09/05387-5 - Dynamic Simulation and Position Control of Parallel Manipulator using Predictive Control Techniques.
• Grantee: Fabian Andres Lara Molina
• Support Opportunities: Scholarships in Brazil - Doctorate