Variable-Latency Networked P-PI and MPC Controller Performance for Industrial Robots

Autor: Ali Kilinc, Jan Guhl, Axel Vick
Rok vydání: 2019
Předmět:
Zdroj: ETFA
DOI: 10.1109/etfa.2019.8869169
Popis: The controller design for industrial robot joint positioning is based on fixed cycle times and accurate modeling. Applying closed loop systems to decentralized control networks with variable connection properties would lead to unacceptable performance drops of the controlled mechanism. On the other hand service-oriented and networked control modules are providing full flexibility of location independent execution. But using wide-area connection like internet or wireless networks is yielding unpredictable latency and jitter conditions. That is not well handled by standard feedback controllers like PID or P-PI cascades. This paper presents the comparison of a modified MPC to a standard P-PI controller. That comparison reveals the strengths and weaknesses of each approach regarding controller performance under different communication conditions. Reusing the MPC control trajectory allows the robot to follow a small open-loop trajectory during latency deviation. That improves the performance criteria like overshoot and damping significantly. The overall robustness of the modified MPC is demonstrated empirically by extensive experiments with an laboratory industrial robot.
Databáze: OpenAIRE