US Patent 7606648 Operator display system

An operator display system for a material handling vehicle, the material handing vehicle having a material handling device comprising an arm and a material handling implement mounted on the arm, the operator display system being operable to receive input information comprising information relating to the orientation of the arm and of the material handling implement and calculate the position of the material handling implement, the operator display system further having a head-up display, the operator display system being operable to generate an output in accordance with the input information and display the output on the head-up display.