A Bayesian Approach to Feedback Control for Hyperbolic Balance Laws
Markus Bambach, Shaoshuai Chu, Michael Herty, Yunong Lin
TL;DR
The paper addresses stabilizing boundary control for one-dimensional hyperbolic balance laws in the form $\mathbf{U}_t + \mathbf{F}(\mathbf{U})_x = \mathbf{S}(\mathbf{U})$ by introducing a Bayesian framework that evolves a posterior over boundary gains $\kappa$ using Lyapunov decay as the data. The method is discretization-agnostic and nonintrusive, relying on a first-order LLF scheme (extensible to second order) and Bayes’ rule with a damping mechanism to concentrate probability on stabilizing parameters. Across linear and nonlinear deterministic cases, stochastic variants, nonconservative systems, and a two-parameter LPBF example, the approach recovers known stability domains and remains robust to prior choices and indicator choices. The work demonstrates a practical route to identify stabilizing boundary controls in complex, possibly nonlinear or stochastic settings, with potential extensions to networks and multi-parameter controls. The contribution is significant for computational control of hyperbolic systems, providing a data-driven, solver-compatible tool to delineate stability ranges without requiring bespoke Lyapunov functionals for each problem.
Abstract
We propose a Bayesian framework for feedback boundary control for hyperbolic balance laws. The method propagates a probability distribution over feedback parameters by using Lyapunov decay estimates as a likelihood. In the linear setting, the framework recovers the available analytical results, while simultaneously extending them to nonlinear regimes where such results are not readily accessible. We first validate the method using the first-order local Lax-Friedrichs (LLF) discretizations on linear models -- the decoupled wave system and the linearized Saint-Venant equations -- recovering the known stability intervals and mixed boundary couplings reported in the control literature. We then consider nonlinear and stochastic settings, including the nonlinear Saint-Venant system and Burgers equation with random initial data, as well as a nonconservative perturbation with source terms, and demonstrate that the computed stability domains remain accurate and robust with respect to the choice of indicator and the initial prior. We further show that the methodology carries over to a second-order semi-discrete LLF scheme and to a model with two interacting control parameters for the temperature field development in laser powder bed fusion with feedback power regulation. These numerical experiments confirm consistency with available theory on benchmark cases and highlight the practicality of the proposed, discretization-agnostic feedback selection procedure.
