A vehicle inspection apparatus includes: an exciter roller (3) configured to apply vibration to a vehicle (6); a control device 5 configured to control the exciter roller (3); and a vibration setting unit (the control device (5)) configured to set a vibration that is input to a wheel (7) of the vehicle (6) when abnormal noise generated in the vehicle (6) is detected. The control device (5) provides a range of vibrations including the vibration set by the vibration setting unit and applies the range of vibrations to the vehicle (6).

An acceleration device includes an actuator configured to displace a mass in a reciprocating motion at a desired frequency, a mount configured to hold a device, such as an accelerometer device, and at least one spring connecting the mount to the mass. The actuator is used to apply a force to achieve resonance. The actuator may comprise a voice coil motor, wherein the voice coil motor includes a permanent magnet and an armature and wherein said armature comprises part of said mass. The actuator applies a periodic force to the mass. The periodic force may be a sinusoidal force. Preferably, the applied force is aligned with a resulting velocity of the mass. The mount may include a test socket to which the device is electrically connected. The spring may comprises one or more flexure elements. The acceleration device may be used with a handler device to connect and disconnect the device to and from the mount. Optionally, the handler device includes an environmental chamber surrounding the mount.

An actuator includes a cylinder sandwiched between a fixing plate fixed to the other end surface of a supporting plate together with a servomotor and a bearing housing, a ball screw shaft having one end protruding into the cylinder through through holes of the fixing plate, a slide block screwed with one end of the ball screw shaft in the cylinder, a cylindrical-shaped piston coupled to an end of the slide block and reciprocatably located in the cylinder, linear motion bearing units located inside the bearing housing to movably support the piston, and linear motion bearing units located in the cylinder to movably support the slide block.

A shaker test system with a class D power amplifier having an analog to digital converter to receive an analog input signal and convert the analog input signal to a digital signal, pulse width modulation logic coupled to the analog to digital converter to provide a delay time to a delay line to control a transition time of a pulse width modulated signal responsive to an output of the analog to digital converter, and a class D power output stage coupled to the delay line and responsive to the pulse width modulated signal to provide an output of the class D power amplifier stage. The class D amplifier allows use of a low cost microcontroller to obtain very small pulse width increments using a low cost microcontroller to provide a low cost shaker test system incorporating the class D power amplifier.

An apparatus and method for inducing multiaxial vibrations to simulate an environment for transporting a stack of products is provided. A lower platform is provided for inducing uniaxial vibrations. A link is connected to the lower platform by a lower end of the link. The upper end of the link has a universal joint, through which the link is connected to an upper platform. The upper platform has a top surface, on which the stack of products can be placed. In operations, the uniaxial vibrations of the lower platform are transferred to the upper platform through the link and the universal joint, to induce pivotal movement of the upper platform with respect to the shaft of the link. As a result, multiaxial vibrations can be induced to the stack of products placed on the top surface of the upper platform.

The present invention relates to an embedded shaking table with heavy load capacity and extensible test frequency and area, comprising a shaking table body; the shaking table body is arranged in a building foundation in which a long-stroke groove is formed, a plurality of long-stroke servo actuators are horizontally and vertically hinged in the shaking table; a short-stroke groove being formed on the upper end of the shaking table body; an excitation platform being arranged in the short-stroke groove; a plurality of short-stroke servo actuators are horizontally and vertically hinged in the shaking table. The present invention is aimed at providing a large-scale and heavy-load embedded shaking table that can meet the test requirements of realizing long stroke and high-frequency loading.

The present invention relates to a modular shaking table with heavy load capacity and extensible test frequency and area, comprising a shaking table body; the shaking table body is arranged in a building foundation in which a long-stroke groove is formed, long-stroke servo actuators are horizontally and vertically hinged in the modular shaking table; and an integration foundation is fixedly arranged on the upper end face of the shaking table body; an excitation platform is arranged in a short-stroke groove that is formed in the integration foundation, short-stroke servo actuators are horizontally and vertically hinged in the modular shaking table. The present invention is aimed at providing a large-scale and heavy-load modular shaking table that can meet the test requirements of realizing long stroke and high-frequency loading.

A method for stabilizing a track having sleepers supported on a track ballast and rails secured to the sleepers, includes using a stabilizing unit which is connected to a machine frame that can be moved on the rails and has a vibration exciter and rollers that can roll on the rails. The vibration exciter generates in particular horizontal vibrations which run transversely to the track longitudinal direction. The course of a force exerted onto the track by the stabilizing unit is recorded over a vibration path during a vibration cycle by sensors. At least one parameter is derived from the course by an evaluation device and is used to evaluate the stabilizing procedure and/or the quality of the track ballast. A device for implementing the method is also provided.

An object of the present invention is to provide a dynamic characteristic measurement device capable of accurately measuring dynamic vibration characteristics of a rubber isolator and the like in a high-frequency vibration range. A dynamic characteristic measurement device according to the present invention includes a base, a support part that is placed above the base so as to be capable of floating via an air spring, an electrodynamic vibrator that is provided on the base side of an object under test mounted between the base and the support part and vibrates the object under test, and a load washer that is provided on the support part side of the object under test and measures a dynamic load applied to the object under test. Here, a crosshead of the support part is shaped such that a resonant frequency is at least 3 kHz.

Devices, systems, and techniques are described that relate to the monitoring of various types of components in industrial systems. These include battery-less monitors that run on power harvested from their environments, systems for acquiring monitor data for the components in a facility, and/or techniques for processing monitor data to reliably determine the status of individual components and other system parameters.