Abstract: A method and apparatus is disclosed for recursively estimating vehicle mass and/or aerodynamic coefficient of a moving vehicle. The vehicle speed and push force data are collected and a segment of qualified data is then selected from the collected data. Newton's second law is integrated to express vehicle mass and/or aerodynamic coefficient in terms of vehicle push force and vehicle speed. This expression is then used in a recursive analysis of the qualified data segment to determine an estimated vehicle mass and/or aerodynamic coefficient.

Abstract: A method and apparatus is disclosed for recursively estimating vehicle mass and/or aerodynamic coefficient of a moving vehicle. The vehicle speed and push force data are collected and a segment of qualified data is then selected from the collected data. Newton's second law is integrated to express vehicle mass and/or aerodynamic coefficient in terms of vehicle push force and vehicle speed. This expression is then used in a recursive analysis of the qualified data segment to determine an estimated vehicle mass and/or aerodynamic coefficient.

Abstract: A method and apparatus is disclosed for recursively estimating vehicle mass and/or aerodynamic coefficient of a moving vehicle. The vehicle speed and push force data are collected and a segment of qualified data is then selected from the collected data. Newton's second law is integrated to express vehicle mass and/or aerodynamic coefficient in terms of vehicle push force and vehicle speed. This expression is then used in a recursive analysis of the qualified data segment to determine an estimated vehicle mass and/or aerodynamic coefficient.

Abstract: A fuel measurement and control system for a gaseous fuel engine having a solenoid actuated fuel flow control valve which is electronically actuated to control a desired metering duration when the control system is operating in a fuel flow control mode. The fuel measurement and control system further includes mode control valve for switching the control system between a fuel flow control mode and a positive fuel shutoff mode, wherein the fuel flow control valve is prevented from opening when the control system is operating in a positive fuel shutoff mode. The fuel flow control valve includes a pressure balance chamber to balance the biasing forces acting on the valve from the gaseous fuel, wherein gaseous fuel is introduced into the pressure balancing chamber to provide the balancing forces.

Abstract: An apparatus and method for determining start of fuel injection (SOI), preferably in an open nozzle fuel injection system, comprises means for obtaining injector train load data as a function of crank shaft timing, and a computer for sampling the data, performing a smoothing operation thereon, computing a first derivative of the smoothed injector train load data samples with respect to crank shaft timing, computing a maximum value of the first derivative, computing a predefined fraction of the maximum value of the first derivative, and mapping the predefined fraction of the maximum value of the first derivative to its corresponding crank shaft angle, wherein the corresponding crank shaft angle defines the crank shaft angle, measured in degrees relative to piston top dead center, at which SOI occurs. In an alternative embodiment, the smoothing operation and computation of the first derivative may be combined into a single operation.