In the context of networked control systems, event-triggered control (ETC) has emerged as a major topic due to its alleged resource usage reduction capabilities. However, this is mainly supported by numerical simulations, and very little is formally known about the traffic generated by ETC. This work devises a method to estimate, and in some cases to determine exactly, the minimum average intersample time (MAIST) generated by periodic event-triggered control (PETC) of linear systems. The method involves abstracting the traffic model using a bisimulation refinement algorithm and finding the cycle of minimum average length in the graph associated to it. This always gives a lower bound to the actual MAIST. Moreover, if this cycle turns out to be related to a periodic solution of the closed-loop PETC system, the performance metric is exact.

No abstract

We provide a method to construct finite abstractions exactly bisimilar to linear systems under a modified periodic event-triggered control (PETC), when considering as output the inter-event times they generate. Assuming that the initial state lies on a known compact set, these finite-state models can exactly predict all sequences of sampling times until a specified Lyapunov sublevel set is reached. Based on these results, we provide a way to build tight models simulating the traffic of conventional PETC. These models allow computing tight bounds of the PETC average frequency and global exponential stability (GES) decay rate. Our results are demonstrated through a numerical case study.

No abstract

This paper addresses the active control problem of reconfigurable mobile robots on irregular terrain. Different kinematic control strategies to improve robot mobility are proposed based on (a) ground clearance and orientation, (b) ground clearance and stability margin, and (c) wheel traction efficiency. Owing to conflicting objectives associated with these strategies, a multi-objective optimization approach is formulated to determine a set of optimal solutions and establish a trade-off optimal solution. The proposed control is validated through numerical simulations and experimental tests using an amphibious wheel-legged robot, named Environmental Hybrid Robot, designed for environmental monitoring in the Amazon rain forest. C