Abstract: A method of overcoming the problems of measuring the exhaust flow during pulsating and reversing flow by placing a “box” in series within a few feet of the connecting pipe to serve as a filter. The box is constructed with soft expandable sides, so it can expand with the pressure pulsations and then contract, creating a very smooth flow that can be measured with a measuring device at the exit of the flow from the box.

Abstract: A method of overcoming the problems of measuring the exhaust flow from a vehicle engine, which flow is pulsating and reversing, making it difficult to accurately measure. An amount of flow is added to the exhaust flow so that the combined amount of flow exceeds the reversals, and therefore the flow through the primary measuring device is raised a sufficient amount so that the measured flow of the exhaust is always positive. The source of the added flow can be by diverting some of the exhaust flow itself downstream from the measurement device and reintroducing it upstream of the measurement device. In the alternative, the added flow can be from a source external to the exhaust flow.

Abstract: A system and method are provided using a photodetector array for producing an output signal which is compensated for the effects of ambient light, photodetector bias, and the like, wherein the output signal contains information indicative of the position of the object. The preferred embodiment is useful for vehicular wheel alignment and includes left and right wheel units for coupling to respective left and right steerable wheels of a vehicle, and a central microcomputer and CRT display operably coupled with each wheel unit. Each preferred wheel unit includes a photodetector array operably connected to a wheel unit microcomputer and a laser beam source directing a laser beam toward the array of the other wheel unit.

Abstract: An air flow meter (10) has an air flow channel (11) with a vortex generator or strut (13). The cross sectional area of the air flow adjacent the vortex generator is varied to change the flow velocity and hence to change the vortex frequency. The cross sectional area can be changed by rotating strut (13), moving a flexible plate (24) in a sidewall (22), or moving a vortex generator (33) to a region of different cross sectional area.

Abstract: This disclosure describes a method and apparatus for using a single sensor to determine the relative velocity between an object and a fluid stream, the average temperature, pressure and/or density of the fluid stream, and thereby the mass flow of the fluid stream. Select properties of a signal, such as a sonic signal, directed through a vortex street are detected using modifications of existing single sensor vortex volumetric flowmeter methods and apparatus. The modifications facilitate the measurement of mass flow by measurements of the relative energy of the signal and the temperature of the fluid as ascertained from the time delay in signal passage from a signal directing means (43) to a signal receiving means (45).