Control Seminar

Why would one want a multi-agent system unstable

Mrdjan JankovicSenior Technical LeaderFord Motor Company
1311 EECS BuildingMap

Abstract:  In everyday driving, many traffic maneuvers such as merges, lane changes, passing through an intersection, require negotiation between independent actors/agents. The same is true for mobile robots autonomously operating in a space open to other agents (e.g., humans, robots, etc.). Negotiation is an inherently difficult concept to code into a software algorithm. It has been observed in computer simulations that some “decentralized” algorithms produce gridlocks while others never do. It has turned out that gridlocking algorithms create locally stable equilibria in the joint inter-agent space, while, for those that don’t gridlock, equilibria are unstable – hence the title of the talk.

We use Control Barrier Function (CBF) based methods to provide collision avoidance guarantees. The main advantage of CBFs is that they result in relatively easier to solve convex programs even for nonlinear system dynamics and inherently non-convex obstacle avoidance problems. Six different CBF-based control policies were compared for collision avoidance and liveness (fluidity of motion, absence of gridlocks) on a 5-agent, holonomic-robot system. The outcome was then correlated with stability analysis on a simpler, yet representative problem. The results are illustrated by extensive simulations and a vehicle experiment with stationary obstacles.

Bio:  Mrdjan Jankovic received his undergraduate engineering degree from Belgrade University in 1986 and doctoral degree from Washington University, St. Louis in 1992. He held postdoctoral positions with Washington University and UC Santa Barbara, before joining Ford in 1995. He is currently a Senior Technical Leader at Ford Research, working on development of control technologies for powertrain and driver assist applications. Dr. Jankovic coauthored one book, five book chapters, and more than 140 technical papers. He is a co-inventor of over 90 US patents, with more than 20 used in Ford products sold worldwide. He has been selected to receive 2023 IFAC Nichols Medal and received AACC Control Engineering Practice Award (2016), IEEE Control Systems Technology Award (2010), Ford’s prestigious Dr. Haren Gandhi Research and Innovation Award (2018), and best paper awards from IEEE, SAE, and AVEC. Dr. Jankovic is a Fellow of the IEEE and a member of the US National Academy of Engineering.


***Event will take place in hybrid format. The location for in-person attendance will be room 1311 EECS.   Attendance will also be possible via Zoom. Zoom link and password will be distributed to the Controls Group e-mail list-serv.

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This seminar will be recorded and posted to the Control Seminar website

Faculty Host

Jim FreudenbergProfessor, Electrical Engineering and Computer ScienceUniversity of Michigan