Abstract: In order to reduce the excitation of vibrations and resonances in a test bed for a real component and a virtual component, one of the following method steps is provided: a) determining a first correction value (K1) from the measured variable (M), wherein the first correction value (K1) is added to the measured variable (M) and the sum is communicated as a corrected measured variable (M*) to the virtual component for calculating the control variable (S), b) determining a second correction value (K2) from the calculated control variable (S), wherein the second correction value (K2) is added to the calculated control variable (S) and the sum is transferred as a corrected control variable (S*) to the actuator, c) determining a third correction value (K3) from the measured variable (M), wherein the third correction value (K3) is used to modify a parameter (P) of the equation of movement.

Abstract: A test structure includes a frame, a shear reduction plate configured to couple to a first end of a test asset, and multiple rockers. Each rocker includes a first end that has a curved contact surface configured to contact the shear reduction plate and a second end having a connector movably coupled to the frame and configured to pivot, responsive to a bending moment applied to the test asset, such that the curved contact surface rocks in contact with the shear reduction plate.

Abstract: The present invention relates to a method of monitoring the effectiveness of a damper system, wherein the method consists in measuring the relative movements of two strength members, in filtering the measurements in order to isolate those that relate to the lead-lag resonant frequency of the blade, in rectifying the signal, in recording the signal, in comparing the rectified signal (S) with a threshold value (SL), in determining an initial time interval (T0) as soon as the rectified signal exceeds the threshold value (SL), in calculating the integrals of the signal from T0 to T0+? and from T0 to T0+p?, in calculating the ratio R of the integrals, and in comparing the ratio R with a limit value RL, and in activating and delivering an alert signal (V1) if the ratio R is greater than or equal to the limit value RL.

Abstract: A method for checking a vibration damper of a motor vehicle in the installed state includes setting start values of the damping constant kA, the spring rate cA, and the body mass mA for a wheel of a motor vehicle; inducing a vertical vibration of the motor vehicle with the aid of a defined excitation sRreal; determining the theoretical body vibration excursion sAmodel; optically detecting the positions of the wheel and the body shell of the motor vehicle at a plurality of detection instants during the vibration; minimizing the error function formed from the deviations between the theoretical body vibration excursion sAmodel and the observed body vibration excursion sAreal at the detection instants, and determining the damping constant kA, the spring rate cA, and the body mass mA therefrom; and determining the damping measure ? of the vibration damper.

Abstract: A system for determining acceptability of torsional dampers for service in a machine system includes a fixture, an ultrasonic scanner and an indicating device configured to indicate at least one of acceptability and unacceptability of a torsional damper based upon receipt of a signal from the scanner. A nondestructive testing method for a torsional vibration damper includes scanning a torsional vibration damper with ultrasonic energy, and determining a test value for the damper indicative of a viscosity of fluid sealed within a housing of the damper based on receiving transmitted ultrasonic energy. Receipt of ultrasonic energy may be used to determine the flow rate of fluid within the damper by indicating a time for fluid to flow to fill a void within the damper. The system and method may be implemented in a remanufacturing or salvaging process for torsional vibration dampers.

Abstract: A pneumatic device selection system has a computer, first through sixth databases connected to the computer and storing data of at least pneumatic devices, a coordinate input unit and a keyboard connected to the computer, for entering input data based on an input action of an operator into the computer, and a display unit connected to the computer, for displaying information from the computer. The pneumatic device selection system functionally has a first selection processor for selecting a cylinder operating system based on input data from the coordinate input unit or the like, and a second selection processor for selecting a shock absorber based on input data from the coordinate input unit or the like and/or a selection result from the first selection processor.

Abstract: A control system is operable to selectably activate shock damping devices associated with a bicycle so as to eliminate bobbing encountered under extreme pedaling conditions. The system includes a crank axle torque detector which operates to detect a level of torque applied to a crank axle and provide a control signal corresponding to the level of torque. A shock damping device is coupled to the frame of the cycle, and functions to absorb and dampen mechanical shocks communicated to the frame. The shock damping device includes an activator for controlling its damping function. The activator is operable to receive the control signal from the crank axle torque detector and control the shock damping device in response thereto. The control signal may be an electrical or a mechanical signal.

Abstract: A device for the testing and monitoring of the function of a shock wave or pressure wave source is provided. The testing and monitoring device is characterized in that a passive non-linear transmission element transforms very short shock wave pulses received by it, the shock wave pulses typically having pulse durations lasting a few microseconds, into a considerably lower frequency range, whose oscillations are then sensed and evaluated.

Abstract: A damping performance evaluation apparatus for damping devices including: a support member detachably supporting a damping device in a state enabling the device to exhibit a damping effect thereof; a hammer member for applying oscillation force to the device caused by gravitational descent to strike the device; a double-strike preventing member for preventing the hammer member from dropping a second time due to rebound after initially striking the device, to prevent double-strike of the device by the hammer member; a vibration sensor installed at a vibration zone caused to vibrate through oscillation force applied by said hammer member, for outputting an electrical signal in response to vibration at the vibration zone; and a sensing member for sensing a vibration mode in the vibration zone on the basis of an output of said vibration sensor. A damping performance evaluation method is also disclosed.

Abstract: An apparatus for testing torsion bars, comprising a frame, a load cell, a connector, a torque arm and a force applicator. The frame includes a torque end support positioned a predetermined distances from a load cell end support. The load cell is attached to the load cell end support, and the connector is rotatably attached to the torque end support. A torsion bar is connected to and extends between the load cell and the connector. The torque arm has a proximal portion attached to the connector, and at least one distal portion. The force applicator is attached to the distal portion of the torque arm and to the frame. The force applicator rotates the torque arm and provides a torque force to the torsion bar.

Abstract: The vibration damping capability of a test part can be computed by vibrating the test part at different frequencies, and measuring the amplitude of the vibrational wave generated in the test part at each input frequency. The test data can be used to generate a measurement curve plotting vibration amplitude against frequency.

Abstract: The vibration damping properties of brake rotors and drums can be represented accurately and repeatably by a single factor obtained from a curve fitting based on an eighth order sine function. A series of test points taken only around one or more vibrational antinodes is used to measure resonant frequencies and vibration decay times around the periphery of a part. This data is then used to determine Q-factors, which are found to vary sinusoidally around an annular brake part.

Abstract: The vibration damping properties of a brake rotor (or other vibration-prone component) can be measured by vibrating the component part at its resonant frequency, using a magnetic coil that is excited by an A.C. signal having a frequency that is one half the frequency of the vibrating wave generated in the component. The A.C. signal crosses the zero current axis twice per current cycle, so that the magnetic flux in the coil core reverses polarity at the frequency selected for vibrating the part.