Dynamic output-based feedback stabilizability for linear parabolic equations with memory
Arbaz Khan, Sumit Mahajan, Sérgio S. Rodrigues
TL;DR
This work develops a dynamic output-based feedback framework for linear parabolic equations with memory, enabling stabilization through explicit projections-based input and output injections realized by finite actuator/sensor arrays. A dynamic Luenberger observer supplies state estimates used in the control law, with stability proven under a set of verifiable assumptions and kernel properties; for exponential kernels, the authors prove exponential stabilizability with rate equal to the kernel rate $\gamma$, and validate the results via thorough numerical experiments using finite elements and IMEX time integration. The study demonstrates that large enough actuator/sensor configurations and gain choices render the coupled system exponentially stable, while memory terms influence the achievable rate and require careful discretization of the memory integral. Notably, a static-output variant is shown to be feasible when actuators also carry sensors, yielding a purely output-driven stabilizing law with explicit gains. The results have practical significance for control of distributed-parameter systems with history effects, and open doors to extensions to nonlinear dynamics and optimized sensor/actuator placements.
Abstract
The stabilizability of a general class of linear parabolic equations with a memory term, is achieve by explicit output feedback. The control input is given as a function of a state-estimate provided by an exponential dynamic Luenberger observer based on the output of sensor measurements. The numbers of actuators and sensors are finite. The feedback input and output injection operators are given explicitly involving appropriate orthogonal projections. For exponential kernels, exponential stabilizability can be achieved with the rate of the exponential kernel. The discretization and simulation of the controlled systems are addressed as well and results of simulations are reported showing the performance of the proposed dynamic output-based control feedback input. We include simulations for both exponential and weakly singular Riesz kernels, showing the success of the strategy in obtaining a stabilizing input.
