Optimal Control of Nonconvex Sweeping Processes with Variable Time via Finite-Difference Approximations
Tan H. Cao, Boris S. Mordukhovich, Dao Nguyen, Trang Nguyen, Nguyen N. Thieu
TL;DR
This work advances optimal control for nonconvex sweeping processes with variable time by introducing and validating discrete-approximation methods that strongly converge to continuous-time optima. It develops a comprehensive variational-analysis toolkit, including second-order subdifferentials and coderivative calculus, to obtain necessary optimality conditions for discrete approximations and their continuous-time counterparts. The methodology is then demonstrated on motion-model applications, enabling computation of optimal times and controls and revealing interaction patterns such as pre-contact acceleration and post-contact synchronization. The results offer a rigorous pathway from discrete, tractable problems to complex free-time sweeping-control problems with nonpolyhedral moving sets, with potential impact on robotics, traffic, and nanotechnology modeling.
Abstract
The paper is devoted to the study of a new class of optimal control problems for nonsmooth dynamical systems governed by nonconvex discontinuous differential inclusions of the sweeping type with involving variable time into optimization. We develop a novel version of the method of discrete approximations of its own qualitative and numerical importance with establishing its well-posedness and strong convergence to optimal solutions of the controlled sweeping process. Using advanced tools of variational analysis and generalized differentiation leads us to deriving new necessary conditions for optimal solutions to discrete approximation problems, which serve as suboptimality conditions for the original continuous-time controlled sweeping process. The obtained results are applied to a class of motion models of practical interest, where the established necessary conditions are used to investigate the agents' interactions and to develop an algorithm for calculating optimal solutions.
