The present disclosure relates to a photolithography system having an ambulatory projection andor detection gratings that provide for high quality height measurements without the use of an air gauge. All of the fuel for the two-stage power generation system is introduced into the first stage. Redirection of the zero degree boundary to a position where no object appears is described that prevents an object located in the dead zone from being split between margins of the panorama. All API command can, but need not, pass through the proxy. The method entails first using a lane keeping system to detect objects in lanes adjacent to the lane currently occupied by the vehicle and then adjusting the position of the vehicle within the occupied lane-relative to a detected object.