An electrodynamic shaker apparatus is disclosed for providing shaking and/or vibrational motion. The shaker includes armature and stator assemblies as well as a distributed spring assembly. The shaker apparatus of the present invention is robust, supports increased off-center loads, and has a low profile such that it may be easily placed under an item of furniture in order to impart vibrational motion in response to electrical signals from a variety of sources.

Provided is a jig for a vibration test of a stator vane, for use in the vibration test for evaluating high cycle fatigue characteristics of the stator vane, and the jig is provided with a base plate that is fixed onto an excitation table of a shaker, a first fixed wall that is fixed onto the base plate in a state where a vane root end portion of a guide vane is fixed, a movable wall that is slidably placed on the base plate in a state where a vane tip portion of the guide vane is fixed, a second fixed wall that is fixed onto the base plate, and a hydraulic jack that is disposed between the movable wall and the second fixed wall, to apply a load in the span direction to the guide vane. Consequently, in the vibration test for evaluating the high cycle fatigue characteristics of the stator vane, the test simulating an actual operation state can be carried out, and an assumed deformed state can be exhibited in the stator vane to be subjected to the test.

Provided is an exciter device for fatigue testing of a blade of a wind turbine, including a actuator for generating a periodic excitation force and a coupling device for coupling the actuator to a blade to be tested. The exciter device includes a pretensioning device applying a pretension such that the excitation force only acts in a pulling or pushing direction over the whole period.

Provided is an exciter device for fatigue testing of a blade of a wind turbine, including a actuator for generating a periodic excitation force and a coupling device for coupling the actuator to a blade to be tested. The exciter device includes a pretensioning device applying a pretension such that the excitation force only acts in a pulling or pushing direction over the whole period.

A fastener testing system includes a vibration testing apparatus including a test station and a preparation station. The preparation station is configured to have a plurality of test pieces sequentially assembled therein. The test station is configured to sequentially receive and vibrate each assembled test pieces of the plurality of test pieces.

A linear electrical machine (LEM) comprising: at least onestator mounted in a housing, the housing and stator defining a working cylinder; a two-section central core within the working cylinder, wherein the two sections of the core are co-axial, separate and cantilever mounted within the working cylinder; a cylindrical stator bore cavity between the working cylinder and the two central core sections; and one or more hollow translators, each translator being axially movable within the stator bore cavity, such that each section of the central core is traversed by part of the one or more translators, thereby forming an exterior magnetic circuit airgap between the respective translator and stator.

A new vibration test-cell that allows a static load to be applied simultaneously with lateral vibration coupled with in-situ microscopy that allows for the ability to open a fatigue crack up to a desired gap, as well as generate acoustic emission (AE) from vibration excitation, micro-fracture events are captured by the AE measurement while the physical observation of the crack faying surfaces is performed in-situ with an optical microscope embedded in the test cell.

An impact test device includes a control rail and a carriage assembly moveable along the control rail in a plurality of directions including a first direction and a second direction opposite the first direction. The carriage assembly includes a catch configured to engage the control rail to control movement of the carriage assembly. Movement of the carriage assembly in the first direction urges the catch to disengage from the control rail, and movement of the carriage assembly in the second direction urges the catch to engage the control rail.

The present invention belongs to the technical field of oil field drilling, and relates to a ground testing device for a stabilized platform of a rotary steerable drilling tool. The ground testing device includes: a first supporting member and a second supporting member that are oppositely arranged, where the second supporting member is provided with a first mounting hole; a drill collar and a drill collar motor mounted outside the first supporting member, where a motor shaft of the drill collar motor penetrates the first supporting member and is connected to the drill collar, and a stabilized platform mounting assembly is arranged inside the drill collar; and a first vibration member connected to the drill collar and a second vibration member arranged in the first mounting hole in a sleeved manner, where an elastic member is arranged between the second vibration member and the second supporting member, and the elastic member is arranged on the second vibration member in a sleeving manner. An end portion of the first vibration member is provided with first vibration teeth, an end portion of the second vibration member is provided with second vibration teeth matching the first vibration teeth, and the second vibration member is provided with a first stop member which matches a second stop member arranged in the first mounting hole. According to the present invention, vibration, interference loading, and high-temperature simulation can be performed, and ground tests of different types of mechanical stabilized platforms are achieved.

An impact test device includes a control rail and a carriage assembly moveable along the control rail in a plurality of directions including a first direction and a second direction opposite the first direction. The carriage assembly includes a catch configured to engage the control rail to control movement of the carriage assembly. Movement of the carriage assembly in the first direction urges the catch to disengage from the control rail, and movement of the carriage assembly in the second direction urges the catch to engage the control rail.