Co-Design of Robust and Secure Networked Embedded Control Systems

ResearchersYang Xu, Anton Cervin, and Karl-Erik Årzén, in collaboration with the Embedded Systems Lab at Linköping University

Funding: ELLIIT

In the design of embedded control systems it is important to use the limited platform resources (e.g., CPU time, network bandwidth, energy) as efficiently as possible. At the same time, any optimistic assumptions at design time may lead to runtime failures caused by missed deadlines, lost controls, or energy depletion. In this project we aim to develop theory and co-design methodology for robust and secure embedded control systems that should operate efficiently also in the presence of uncertainties or unforeseen events. We will consider robustness towards, among other things, plant perturbations, malicious intrusion, execution-time overruns, and varying network capacity.

Working along two parallel research paths, we will explore both passive and active approaches to achieve robustness. In the passive approach, we aim for techniques that take parametric plant and platform uncertainty into account at design time, while the run-time system should provide predictable exception handling and provable performance bounds. In the active approach, the run-time system should be able to adapt to new and unexpected conditions via reconfiguration and self-optimization. Here a great research challenge is to devise adaptation schemes that do not consume too much resources in themselves. One aspect of high interest is intrusion detection for highly resource-constrained control applications. In such a context, solutions have to deliver not only according to the traditional metrics of false-positive and false-negative, but also perform well according to new, specific quality metrics: detection latency, power consumption, processor load, and communication overhead.

During 2017, the research focused on jitter-robust LQG design. Adding a jitter margin constraint to a standard LQG formulation makes it possible to trade off performance and timing robustness for real-time controllers. On December 15, Yang Xu defended his PhD thesis with the title "LQG-Based Real-Time Scheduling and Control Codesign".