a cleaning apparatus for cleaning a surface in which cleaning solution is dispensed to the surface and substantially simultaneously extracted along with the dirt on the surface in a continuous operation is provided . the cleaning apparatus includes a base assembly that moves along the surface . a liquid distribution system is associated with the base assembly and includes a source providing a supply of cleaning solution to a distributor fluidly connected to the source . a liquid recovery system is also associated with the base assembly and includes a suction nozzle . a suction source is in fluid communication with the suction nozzle for applying suction to draw the cleaning solution and dirt from the surface through the suction nozzle . the cleaning apparatus further includes a detecting device for detecting the speed of the cleaning apparatus as it moves along the surface and producing a speed signal representing the speed of the cleaning apparatus relative to the surface . a controller , operatively connected to the detecting device and a component on the cleaning apparatus , controls the function of the component based on the speed signal . the controller can also control the function of the component based on signal representing other operating characteristics of the cleaning machine .