A method for testing a rotor blade of a wind turbine may include predefining a setpoint bending moment distribution. At least two active load-introducing means may be provided which each engage on a load frame. A first of the at least two active load-introducing means may be configured for introducing load in a pivot direction of the rotor blade and a second of the at least two active load-introducing means may be configured for introducing load in an impact direction of the rotor blade. Also provided is at least one passive load-introducing means. A cyclic introduction of load is effected by the at least two active load-introducing means, where a load introduction frequency of the first active load-introducing means and a load introduction frequency of the second active load-introducing means are selected such that the ratio thereof is rational. A testing device for carrying out the method is also provided.

The disclosed embodiments relate to a test stand for the simulation of the vibration behavior of a vehicle. The test stand comprises a receiving element for contacting with a vehicle and an excitation system for the application of excitation frequencies. The excitation system comprises a main actuator system with at least one movable main actuator and an additional actuator system with at least one movable additional actuator, the additional actuator system being connected to the main actuator system.

A method of determining a noise or vibration response of a vehicle subassembly may include transmitting, via a controller, an input torque control signal to a first motor of a test apparatus. The first motor is mountable on a test fixture of the test apparatus and is configured to be coupled to the vehicle subassembly. The input torque control signal causes the first motor to provide an input torque characterized as a third derivative Gaussian function. The method further includes receiving a response of the vehicle subassembly to the input torque, and executing a control action with respect to the vehicle subassembly, via the controller, based on the response.

An apparatus for carrying out load testing on an aircraft part is described. In one aspect, the apparatus includes means for constraining the aircraft part and a linear actuator for applying a test load. The linear actuator has a first part being tiltable and being pivotally constrained about a first and a second geometrical axes, orthogonal to one another, and a second part being slidably mounted on the first part to slide along a longitudinal direction. A load cell, mounted on the second part, measures force acting on the aircraft part along the longitudinal direction. In one aspect, a first clinometer and a second clinometer are mounted on the linear actuator, each clinometer measuring a respective angle representative of rotation of the linear actuator respectively about the first and second geometrical axes. A displacement transducer measures sliding of the second part relative to the first part of the linear actuator.

A method of designing a test fixture configured to mount to a vibration slip table and fix a test article to the vibration slip table during a vibration test includes performing finite element analysis using one or more boundary conditions determined from parameters of the vibration slip table, the test article, or the vibration test to optimize a topology of the test fixture, and outputting a geometric model of the test fixture having the optimized topology. Another method of designing a test fixture includes inputting the one or more boundary conditions into a topology optimizing solver. A vibration test system includes a test fixture designed according to the method.

A vehicle-body carrying apparatus is configured to house and carry a vehicle body of an unmanned vehicle. The apparatus includes a housing, a data collecting device, a diagnostic device, and an informing device. The housing is capable of housing the vehicle body. The data collecting device is configured to collect data relating to structural soundness of the vehicle body housed in the housing. The diagnostic device is configured to diagnose the structural soundness of the vehicle body based on the collected data. The informing device is configured to inform a user of a diagnostic result obtained by the diagnostic device.

Provided is a method of controlling vibration in an artificial satellite vibration test by using a controller and a plurality of shakers installed on an artificial satellite and configured to vibrate at a predetermined frequency. The method includes: performing a pre-test operation in which the controller sets the artificial satellite as a system and calculates a plurality of input values using a frequency response function of the system and an inverse matrix of the frequency response function; determining, by the controller, whether errors, which are differences between target values and a plurality of output values resulting from the plurality of input values, are within a first range; and performing, by the controller depending on results of the determination, single shaker control using one of the plurality of shakers, or multiple shaker control using the plurality of shakers.

An acoustic or mechanical vibration testing system includes a MIMO control system coupled to at least two separately controllable groups of vibration transducers and at least two control sensor transducers wherein the number of control sensor transducers need not be equal to the number of controller output drives or number of separately controllable groups of vibration transducers. The MIMO control system utilizes both a predetermined initial reference specification and a modified reference specification, wherein data acquired during system operation under conventional MIMO control is used to create the modified reference specification based on actual system performance and limitations thereof so as to maintain closer correspondence to the predetermined initial reference specification with less required system drive power, as a function of the predetermined initial reference, and less risk of damage to the test system and the test article during the performance of a test.

A method of evaluating a natural frequency of a piezoelectric vibrator including a vibrating membrane and a piezoelectric element, includes: acquiring power-generating wave information of the piezoelectric vibrator from vibration of the vibrating membrane, which is caused by generating an electric field in a piezoelectric film of the piezoelectric element to displace the vibrating membrane and then extinguishing the electric field in a state where the vibrating membrane is displaced; and measuring a period of a power-generating wave based on the power-generating wave information and determining a reciprocal of the period as the natural frequency of the piezoelectric vibrator.

An apparatus for carrying out load testing on an aircraft part has constraint means for constraining the aircraft part, a linear actuator for applying a test load, having a tiltable first part, pivotally constrained about a first and a second geometrical axes, orthogonal to one another, and a second part, slidably mounted on the first part to slide along a longitudinal direction. A load cell, mounted on the second part, measures a force acting on the aircraft part along the longitudinal direction. A first clinometer and a second clinometer are mounted on the linear actuator. Each clinometer measures a respective angle representative of rotation of the linear actuator respectively about the first and second geometrical axes. A displacement transducer, mounted on the first part, measures sliding of the second part relative to the first part of the linear actuator.