water skimmer which floats on the surface of a body of water the skimmer is propelled by an on board propulsion unit and collects and traps floating debris along its movement path a guide mechanism is provided to sense the presence of obstacles in the path of the skimmer the guide mechanism acts on a thrust vectoring means in response to a detected obstacle to change the direction of motion of the skimmer application_number US 24833299 A description in fig1 body 2 of skimmer 1 is shown with duct 4 and trailing net 3 body 2 may be made from suitable materials such as sandwiched polystyrene or a plastic material which will provide a strong but buoyant body in use the lower edge of duct 4 will be below the surface of the water while the upper edge of duct 4 will be above the surface of the water as the skimmer moves across the surface of the pool water enters opening 5 of duct 4 passes through duct 4 and exits the duct through opening 6 at the rear end of the body any debris floating on the surface of the water passing through the duct is trapped in net 3 preferably there will be a floating boom not shown at.