Null controllability of the structurally damped wave equation with   moving point control
  We investigate the internal controllability of the wave equation with structural damping on the one dimensional torus. We assume that the control is acting on a moving point or on a moving small interval with a constant velocity. We prove that the null controllability holds in some suitable Sobolev space and after a fixed positive time independent of the initial conditions. 
Philippe Martin, Lionel Rosier, Pierre Rouchon
math.OC math.AP