Abstract: The invention relates to a method and an apparatus for the mass simulation of vehicle masses on a stationary roller test stand, wherein the simulation mass (msim) is determined from the test stand mass (mP) and from the mass (mRad h?) of the non-driven rotatable vehicle parts that are determined by measuring techniques, as well as from the mass (mRad h?) of the driven rotatable vehicle parts that are determined by measuring techniques, and with the aid of the translatory vehicle mass (mF), in an evaluating device (10) of the test stand.

Abstract: A vehicle wheel support device for use in a wheel alignment assembly including a floating plate assembly movably supported relative to the base upon which a vehicle is positioned. The floating plate assembly includes a pair of rollers disposed in a fixed non-parallel orientation with respect to each other. The floating plate assembly is movably positioned such that a vehicle wheel may be located between the pair of rollers to isolate the vehicle wheel from the base so as to stabilize all forces acting thereon and wherein the rollers rotate the wheel so that various wheel alignment parameters may be measured.

Abstract: A method and apparatus for multi-channel control of a multiple input, multiple output, servo-driven plant utilizes finite impulse response (FIR) filters to model the inverse of the plant. Each channel includes a servo FIR filter that generates a servo command to drive the plant's servo controller, a valve current FIR filter that bypasses the PID stage of the servo controller to avoid undesirable effects of the PID loop, and a cross FIR filter for each of the remaining channels that compensates for physical coupling in the plant between the channels. The servo FIR filter is calculated by an adaption routine that involves applying an identification signal to the plant, applying the plant's response to the filter and then updating the filter's coefficients using the error that exists between the identification signal and the filter output.

Abstract: A chassis dynamometer is described which is especially adapted for road simulation. A torque transducer is connected in the roll assembly so that the torque signal is not influenced by bearing friction. The torque transducer outer element is rigidly attached to the roll and the inner element is rigidly attached to the roll shaft.

Abstract: A pneumatic control valve (10) including a valve body (12) with fixed aperture plate (14), a movable redirector (18) and a force motor (26). The force motor (26) supports the redirector (18) adjacent to the aperture surface (16) of the fixed aperture plate (14) and is operable to move the redirector (18) back and forth along a line (28) without contacting the aperture surface. The aperture surface (16) has a plurality of apertures (70,72,74,76,78) with metering edges (124,126,128,130,132,134,136,138). The redirector (18) has redirector cavities (102,104,106,108) with metering edges (140,142,144,146). The force motor (26) deflects the redirector (18) to positions in which one or more of the cavities in the redirector connect two or more of the apertures (70,72,74,76,78) and direct fluid from some apertures and into other apertures. The location, length and shape of the metering edges can be varied as required to obtain desired fluid flow characteristics.

Abstract: Electrohydraulic servovalve structure and method. The servovalve structure has minimum oil passage length and oil volume and a high response force motor with a light weight armature and a stiff flexible tube and includes a second stage pilot valve having an axially movable metering spool therein and a non contacting, electromagnetic, proximity type sensor positioned adjacent one end of the spool for converting axial spool position to an electrical signal. In modifications, a quartz or ceramic window is placed between the one end of the spool and sensor and electronics are placed on the servovalve adjacent the sensor for providing a low impedance spool position output signal from the servovalve. In accordance with the method of the invention, the axial position of the spool is sensed by the eddy current sensor and an electrical signal is provided representative of the position of the spool for use in controlling the electrohydraulic servovalve.

Abstract: A machine for testing ball joints, elastomer bushings or other parts has a pair of mutually rotated gimbals attached to the outer shell or element for applying rotational displacements about two axes and a linear input attached to the inner element to apply a force along another axis. Each axis input is effected by a linear actuator and the gimbal inputs are specially designed to assure accurate independent control without parasitic motion between the inputs. Force and displacement transducers monitor each axis to provide feedback signals to control circuits. A heat chamber including the gimbal assembly has hot air applied from an external source through a hollow gimbal hub to hold the test specimen at a desired temperature.

Abstract: Testing apparatus is disclosed for vehicle steering mechanisms and similar devices for applying a controlled force to a test member. A vertically reciprocable platen carries a hydraulic actuator for applying controlled force to a pivotable test member. The hydraulic actuator is reciprocable along a transverse axis and is connected with the test member by a pivotable coupling. A pivotable link is pivotally connected with a stationary frame and with the mounting frame of the actuator. The distance between the two pivot points on the pivotable link is the same as the distance between the pivot axis of the test member and the pivot axis of the coupling whereby the actuator is caused to traverse an arcuate path when the platen is reciprocated and it thereby follows the arcuate path of the pivotal test member.