Event-Triggered Adaptive Taylor-Lagrange Control for Safety-Critical Systems

TL;DR

This paper introduces an adaptive, event-triggered Taylor-Lagrange control method for safety-critical nonlinear systems, enhancing safety, feasibility, and smoothness over fixed-parameter approaches.

Contribution

It proposes an online, state-dependent parameter selection for Taylor-Lagrange control, enabling dynamic balancing of safety and feasibility in sampled-data systems.

Findings

Improved safety guarantees in simulation of adaptive cruise control.

Enhanced feasibility and smoother control actions compared to fixed-parameter TLC.

Automatic tuning of the discretization parameter improves overall system performance.

Abstract

This paper studies safety-critical control for nonlinear systems under sampled-data implementations of the controller. The recently proposed Taylor--Lagrange Control (TLC) method provides rigorous safety guarantees but relies on a fixed discretization-related parameter, which can lead to infeasibility or unsafety in the presence of input constraints and inter-sampling effects. To address these limitations, we propose an adaptive Taylor--Lagrange Control (aTLC) framework with an event-triggered implementation, where the discretization-related parameter defines the discretization time scale and is selected online as state-dependent rather than fixed. This enables the controller to dynamically balance feasibility and safety by adjusting the effective time scale of the Taylor expansion. The resulting controller is implemented as a sequence of Quadratic Programs (QPs) with input constraints. We further introduce a selection rule to choose the discretization-related parameter from a finite candidate set, favoring feasible inputs and improved safety. Simulation results on an adaptive cruise control (ACC) problem demonstrate that the proposed approach improves feasibility, guarantees safety, and achieves smoother control actions compared to TLC while requiring a single automatically tuned parameter.