Abstract: A control system for estimating the approximate relative position of an electric linear actuator on a surface maintenance machine. The control system includes device for selectively coupling the electric motor of the linear actuator to the electric power source, device for measuring or estimating the current and voltage of the electric motor, device for estimating the motor speed based on the measured values of current and voltage, and storage device for storing values of estimated motor speed and integrating device for determining approximate linear actuator position, wherein the integrating device integrates the motor speed over time to determine the approximate position of the linear actuator position.

Abstract: A power management system for a surface maintenance machine, such as a street sweeper is disclosed. The system includes a variable speed engine for transporting the surface maintenance machine, a hydraulic pump powered by the engine, a vacuum fan motor powered by the hydraulic pump, an engine speed sensor coupled to the engine, an electric proportional valve coupled between the hydraulic pump and the vacuum fan motor, said valve for selectively restricting a flow rate to the vacuum fan motor, and a control unit operatively coupled to the engine speed sensor and the proportional valve, said control unit receiving engine speed information from the engine speed sensor and communicating a predetermined signal to the proportional valve to control the flow rate to the vacuum fan motor as a function of engine speed. A method of managing engine power from a single-engine street sweeper is also disclosed.

Abstract: A power management system for a surface maintenance machine, such as a street sweeper is disclosed. The system includes a variable speed engine for transporting the surface maintenance machine, a hydraulic pump powered by the engine, a vacuum fan motor powered by the hydraulic pump, an engine speed sensor coupled to the engine, an electric proportional valve coupled between the hydraulic pump and the vacuum fan motor, said valve for selectively restricting a flow rate to the vacuum fan motor, and a control unit operatively coupled to the engine speed sensor and the proportional valve, said control unit receiving engine speed information from the engine speed sensor and communicating a predetermined signal to the proportional valve to control the flow rate to the vacuum fan motor as a function of engine speed. A method of managing engine power from a single-engine street sweeper is also disclosed.