Optimal control of level sets dynamics

The problem of optimal tracking of level sets is investigated. More specifically, we propose a novel method to design a controller that is able to track a reference curve generated by a level set equation. Such a functional optimal control problem is nonstandard as it involves a moving domain over time, thus requiring the development of both an ad-hoc approximation scheme and an efficient numerical solver. We address the approximate solution of the resulting optimization problem by using the extended Ritz method, which has been recently applied to the solution of a number of optimal control problems in high dimensional setting. Such a method relies on the use a control law of fixed structure that depends on a number of parameters to be suitably chosen. Toward this end, we derive the adjoint equation for the optimal tracking problem. Such an equation allows one to compute the gradient of the cost function with respect to the vector of parameters of the control law. Numerical results are reported to show the effectiveness and computational effort of the proposed approach for the purpose of tracking curves generated by the normal and mean curvature flow equations.