Vibration and Position Control of a Two-Link Flexible Manipulator Using Reinforcement Learning
Author:
Sasaki Minoru1ORCID, Muguro Joseph2ORCID, Kitano Fumiya3, Njeri Waweru2ORCID, Maeno Daiki3, Matsushita Kojiro3
Affiliation:
1. Intelligent Production Technology Research & Development Center for Aerospace, Tokai National Higher Education and Research System, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan 2. School of Engineering, Dedan Kimathi University of Technology, Nyeri 657-10100, Kenya 3. Department of Mechanical Engineering, Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
Abstract
In recent years, industries have increasingly emphasized the need for high-speed, energy-efficient, and cost-effective solutions. As a result, there has been growing interest in developing flexible link manipulator robots to meet these requirements. However, reducing the weight of the manipulator leads to increased flexibility which, in turn, causes vibrations. This research paper introduces a novel approach for controlling the vibration and motion of a two-link flexible manipulator using reinforcement learning. The proposed system utilizes trust region policy optimization to train the manipulator’s end effector to reach a desired target position, while minimizing vibration and strain at the root of the link. To achieve the research objectives, a 3D model of the flexible-link manipulator is designed, and an optimal reward function is identified to guide the learning process. The results demonstrate that the proposed approach successfully suppresses vibration and strain when moving the end effector to the target position. Furthermore, the trained model is applied to a physical flexible manipulator for real-world control verification. However, it is observed that the performance of the trained model does not meet expectations, due to simulation-to-real challenges. These challenges may include unanticipated differences in dynamics, calibration issues, actuator limitations, or other factors that affect the performance and behavior of the system in the real world. Therefore, further investigations and improvements are recommended to bridge this gap and enhance the applicability of the proposed approach.
Funder
Grants-in-aid for Promotion of Regional Industry-University-Government Collaboration from Cabinet Office, Japan
Subject
Electrical and Electronic Engineering,Industrial and Manufacturing Engineering,Control and Optimization,Mechanical Engineering,Computer Science (miscellaneous),Control and Systems Engineering
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