Kaoru Yamamoto
Associate Professor
Kyushu University
Kaoru Yamamoto received the B.S. and M.S. degree in architectural engineering from Kyoto University, Japan, and the Ph.D. degree in control engineering from the University of Cambridge, U.K., in 2009, 2011, and 2016, respectively. She was subsequently a Postdoctoral Associate at the University of Minnesota Twin Cities, USA, and a Postdoctoral Researcher at Lund University, Sweden. In 2018, she joined the Faculty of Information Science and Electrical Engineering at her current position as an Associate Professor.
Her research interest includes multi-agent systems, multi-robot control, and systems theory.
She is a winner of several scholarships, including the Funai Overseas Scholarship and the Cambridge Overseas Trust Scholarship.
This thesis studies disturbance amplification in interconnected systems, focusing on control of chains of masses and their response to external disturbances. It addresses the design challenges in control of vehicle platoons. The study presents a complex iterative map representation for scalar transfer functions from disturbances to intermass displacements. By analyzing interconnection impedance, the thesis establishes the conditions to achieve string stability for these transfer functions. A graphical method is proposed to select suitable impedance for various chain lengths.
In the field of autonomous mobile robot control, scalability is crucial, but disturbances must be carefully managed. String instability, where faults and errors propagate and amplify within distributed networks of controlled agents, poses significant challenges. To design control strategies involving multiple vehicles and prioritize safety, mitigating this effect is indispensable. Consequently, this research area has been a hot topic for decades.
Despite the importance of disturbance propagation in mobile robot networks, there have been limited investigations. The focus has been primarily on designing controllers optimized for a fixed number of robots, hindering the integration of new agents and real-world applications. String stability analysis remains mostly theoretical, creating a gap between research and practice. However, this work fills this gap by providing a practical and theoretically rigorous approach. The findings offer a nonconservative analysis tool, promoting interdisciplinary dialogue between different scientific communities, practitioners, and theoreticians.
