Local Controls for Large Assemblies of Nonlinear Elements

We introduce a set of local procedures that are capable of controlling distributed systems that exhibit complex dynamical behavior. These local controllers need only perturb local parameters and use local information about the state of the system. Besides eliminating the wiring and overhead needed for implementing a central controller, our procedure leads to desired states in short times. By resoring to a probabalistic dynamical argument, we also show that there are critical values for the couplings among the nonlinear elements beyond which the local controllers do not achieve the desired final state.