<i>L</i>^p-Optimal Boundary Control for the Wave Equation

Abstract

We study problems of boundary controllability with minimal Lp --norm ($p\in [2,\infty]$) for the one-dimensional wave equation, where the state is controlled at both boundaries through Dirichlet or Neumann conditions. The problem is to reach a given terminal state and velocity in a given finite time, while minimizing the Lp --norm of the controls. We give necessary and sufficient conditions for the solvability of this problem. We show as follows how this infinite-dimensional optimization problem can be transformed into a problem which is much simpler: The feasible set of the transformed problem is described by a finite number of simple pointwise equality constraints for the control function in the Dirichlet case while, in the Neumann case, an additional integral equality constraint appears. We provide explicit complete solutions of the problems for all $p\in[2,\infty]$ in the Dirichlet case and solutions for some typical examples in the Neumann case.