ISMA

Professor Kevin L. Moore, Ph.D., P.E.
Dean, College of Engineering and Computational Sciences Colorado School of Mines

Tile: Applications of the Consensus Variable Approach to Coordination and Control - UAVs, Autonomous Mobile Radios, and Energy-Efficient Buildings

In this talk we discuss the consensus variable approach to the coordination and control of cyberphysical systems (those with a tight integration of physical dynamics, sensors and actuators, and computing infrastructure). We begin with an overview of motivating problems and a summary of key results related to the consensus (or agreement) paradigm. We illustrate the application of this idea to several problems, including simulation of swarms, experimental demonstration of formation control of mote-based robots, and experimental demonstration of robotic autonomous mobile radio nodes for wireless tethering between a base station and a leader in a tunnel exploration scenario. We note that a consensus protocol can be represented as a graph with (static) weighted edges and nodes that are integrators. Generalizing this idea, we next present what we call dynamic consensus networks. Such networks are graphs whose nodes are integrators and whose edges are real rational functions representing dynamical systems that couple the nodes. We show that the modeling of thermal processes in buildings motivates such a system and from this motivation we generalize the notions of interconnection matrices and Laplacians to the case of graphs with integrating nodes and dynamic edges. We give conditions under which such graphs admit consensus, meaning that in the steady-state the node variables converge to a common value. Finally, we consider the collective description and properties of the interconnection of one dynamic graph (the plant) with another (the controller). We conclude with a discussion of research questions related to these ideas and to their application to energy-efficient control of buildings and other systems, such as the power grid.

Biography:

Kevin L. Moore is the Dean of the College of Engineering and Computational Sciences at the Colorado School of Mines, where he is the G.A. Dobelman Distinguished Chair and Professor of Engineering. He is also Director of the Center for Robotics, Automation, and Distributed Intelligence. He received the B.S. and M.S. degrees in electrical engineering from Louisiana State University and the University of Southern California, respectively. He received the Ph.D. in electrical engineering, with an emphasis in control theory, from Texas A&M University. He has been a senior scientist at Johns Hopkins University's Applied Physics Laboratory, where he worked in the area of unattended air vehicles, cooperative control, and autonomous systems; an Associate Professor at Idaho State University; and a Professor of Electrical and Computer Engineering at Utah State University, where he was the Director of the Center for Self-Organizing and Intelligent Systems, directing multi-disciplinary research teams of students and professionals developing a variety of autonomous robots for government and commercial applications. He also worked in industry for three years pre-Ph.D as a member of the technical staff at Hughes Aircraft Company. His research interests include iterative learning control, autonomous systems and robotics, and applications of control to industrial and mechatronic systems. He is the co-author of the research monograph Iterative Learning Control: Robustness and Monotonic Convergence for Interval Systems, author of the research monograph Iterative Learning Control for Deterministic Systems, and co-author of the book Sensing, Modeling, and Control of Gas Metal Arc Welding. He is a professional engineer, involved in several professional societies and editorial boards, and is interested in engineering education, particularly capstone senior design. He is a senior member of IEEE and serves as chair of the IEEE Control System Society Technical Committee on Intelligent Control.

Professor Masayoshi Tomizuka
University of California, Berkeley

Title: Enhancing Human Machine Interaction via Mechatronic Actuation 

Abstract:

Mechatronics technologies are applied to assist human in many ways.  One way is to let actuators supply force and torque so that human may accomplish certain tasks with smaller muscular force.  We will examine three different problems of this kind of assistance: 1) mobility assistance for  elderly and partially impaired patients, 2) electric bicycle and 3) variable-gear-ratio steering system  for automobiles.  Actuators for mobility assistance must be compact, generate reasonably large  torque and be back-drivable. Series elastic actuation using a geared motor makes it possible to design a back-drivable light weight high torque actuation system.  In electric bicycle, the human pedal torque is measured and a motor supplies an extra torque to assist the rider.  The assistive strategy considers a unique feature of the human pedal torque that it is not constant but varies over a pedal cycle. In variable-gear-steering, the gear ratio is varied as a function of the vehicle speed to change operability. The variable gear ratio may introduce reaction torque of the steering wheel unnatural to the driver unless the control algorithm is properly designed. 

Biography:

Professor Masayoshi Tomizuka received his B.S. and M.S. degrees in Mechanical Engineering from Keio University, Japan and his Ph. D. degree in Mechanical Engineering from the Massachusetts Institute of Technology. In 1974, he joined the faculty of the Department of Mechanical Engineering at the University of California at Berkeley, where he currently holds the Cheryl and John Neerhout, Jr., Distinguished Professorship Chair and serves as Associate Dean of Engineering. He served as Program Director of the Dynamic Systems and Control Program of the National Science Foundation (2002-2004). He has published over 550 articles in professional journals and conference proceedings. He served as Technical Editor of the ASME Journal of Dynamic Systems, Measurement and Control (J-DSMC), Editor-in-Chief of the IEEE/ASME Transactions on Mechatronics, and Associate Editor of the Journal of the International Federation of Automatic Control (IFAC), Automatica. He served as President of the American Automatic Control Council (AACC) (1998-99) and as Chair of the IFAC Technical Committee on Mechatronic Systems. He is a Fellow of ASME, IEEE, IFAC and SME. He is the recipient of the J-DSMC Best Paper Award (1995, 2000), the DSCD Outstanding Investigator Award (1996), the Charles Russ Richards Memorial Award (ASME, 1997), the Rufus Oldenburger Medal (ASME, 2002) and the John R. Ragazzini Award (AACC, 2006).

Professor Rafael Fierro
Department of Electrical & Computer Engineering, University of New Mexico

Title: Coordination of Multiple Heterogeneous Autonomous Vehicles

Abstract:

Unmanned ground and aerial vehicles are becoming crucial to both civilian and military applications because of their ability to assist humans in carrying out dangerous yet vital missions such as rescue operations and surveillance of hostile environments. The paradigm that emerges from these applications is a set of mobile or stationary targets that must be detected and possibly pursued by multiple heterogeneous mobile platforms. In all of these applications, the vehicle network's performance can be greatly enhanced by coordinating and implementing future sensor actions intelligently, based both on prior knowledge and on the information obtained online. In this talk, we describe an approach that enables prioritized perception and makes use of team of autonomous robots with different capabilities when large search areas need to be investigated. A heterogeneous team allows for the robots to become specialized in their abilities and therefore accomplish sub-goals more efficiently which in turn makes the overall mission more efficient. We also outline a multivehicle test bed and present several algorithms that address the problem of motion planning under connectivity/sensing constraints and illustrate their applicability to different scenarios.

Biography:

Rafael Fierro is an Associate Professor of the Department of Electrical & Computer Engineering, University of New Mexico where he has been since 2007. He received a M.Sc. degree in control engineering from the University of Bradford, England and a Ph.D. degree in electrical engineering from the University of Texas-Arlington. Prior to joining UNM, he held a postdoctoral appointment with the GRASP Lab at the University of Pennsylvania and a faculty position with the Department of Electrical and Computer Engineering at Oklahoma State University. His research interests include cooperative control of multi-agent systems, mobile sensor and robotic networks, motion planning under sensing/communication constraints, multivehicle coordination, cyber-physical systems, and dynamic information flow tracking in computer security. He directs the Multi-Agent, Robotics, Hybrid and Embedded Systems (MARHES) Laboratory. Rafael Fierro was the recipient of a Fulbright Scholarship, a 2004 National Science Foundation CAREER Award, and the 2007 ISA Transactions Best Paper Award. He is serving as Associate Editor for the IEEE Control Systems Magazine and IEEE Transactions on Automation Science and Engineering.