237 results about "Rotation test" patented technology

The invention discloses a retinal blood vessel segmentation method based on the deep-learning adaptive weight, comprising: performing sample expansion on retinal blood vessel images and grouping the samples; constructing a full-convolution neural network for blood vessel segmentation; pre-training the network through the training samples; performing the global adaptive weight segmentation on the retinal blood vessel images; obtaining the initial model parameters for retinal blood vessel segmentation; adding a conditional random field layer to the last network layer and optimizing the network; using the rotation test method to input the testing samples to the network; and obtaining the retinal blood vessel segmentation result. The blood vessel segmentation full-convolution neural network structure and the adaptive weight method proposed by the invention can realize the human-eye level image segmentation and can test on two internationally published retinal image databases DRIVE and CHASE_DB1 with the average accuracy of 96.00 % and 95.17% respectively, both higher than the latest algorithm.

A test fixture for rollover crash testing of a test vehicle onto a movable sled surface employs a cradle to support and rotate the test vehicle. A suspension assembly is attached to each end of the cradle for vertically supporting and dropping the cradle. A gantry has a cross beam supported by a first telescoping column for support of a first of the suspension assemblies and translationally supported by a second telescoping column for support of a second of the suspension assemblies to position and releasably hold the suspension assembly. Roll control arms rotate the cradle and a trigger assembly releases the cradle and test vehicle from the cross beam for contact within a drop impact zone on the contact surface of the sled. A brake assembly then arrests vertical motion of the cradle.

A test facility includes a heat source to thermally load a test object being mechanically loaded by rotation imposed by a spin test rig. The heat source can be a quartz lamp controlled to provide a thermal load with a differing phase than the mechanical load. Testing cycles can be run for the test object, with impingement cooling permitting the removal of the thermal load between cycles. The test facility emulates operating conditions in a gas turbine engine to impose realistic thermal and mechanical fatigue stress on the test component.

The invention relates to a device for testing vortex-excited oscillation and rotation of a vertical riser pipe under a uniform flow and a stepped uniform flow, belonging to the technical field of ocean engineering. The device comprises a riser pipe model mechanism, a measurement and analysis system platform module, a driving module, a top cantilever module, a bottom cantilever module, a cylindrical shaft segmentation module and a bottom support module, wherein the riser pipe model mechanism is fixedly arranged between the bottom cantilever module and the top cantilever module; the cylindricalshaft segmentation module is perpendicularly arranged in a deep ocean engineering pool and is respectively and perpendicularly connected with the bottom support module, the driving module and the topcantilever module; the bottom support module is fixedly arranged on a lifting bottom; the driving module is respectively connected with the cylindrical shaft segmentation module and the top cantilever module; the left end and the right end of the top cantilever module are respectively connected with the cylindrical shaft segmentation module; and the measurement and analysis system platform moduleis respectively connected with a riser pipe model, the top cantilever module and the bottom cantilever module. By using the invention, the uniform or stepped flow field of a riser pipe with an actualsize can be simulated.

The invention discloses a rotary reciprocating frictional wear testing machine which comprises a rack provided with a rack workbench, a rotation test device, a linear reciprocating test device, a testforce loading mechanism and a sample clamping module. The rotation test device comprises a rotation driving motor. The rotary driving motor is vertically arranged in the rack and is positioned at a lower part of the rack workbench. The linear reciprocating test device comprises a reciprocating motion linear motor which is a voice coil motor. The reciprocating motion linear motor is horizontally arranged on the rack, an axis of the reciprocating motion linear motor perpendicularly intersects with an axis of the rotary driving motor, the sample clamping module is detachably mounted on the rackworkbench and is coaxial with the axis of the rotary driving motor. The test force loading mechanism comprises a lifting mechanism and a force application mechanism, the lifting mechanism is arrangedon the rack, the force application mechanism comprises a force application shaft, a measurement sensor connected to the force application shaft and an upper sample clamp connected to a lower end of the force application shaft, and the force application mechanism is connected to the lifting mechanism.

The invention provides a rigidity test restraining device of a car frame and a corresponding restraining method thereof. When the rigidity of the car frame is tested by the method, the car frame is formed to be a simply supported beam structure during testing the bending rigidity and reversing rigidity, thus releasing three rotation degrees of freedom and necessary translation degrees of freedom at corresponding restraining positions; through the restraining device, the three rotation degrees of freedom at the corresponding restraining positions are released on the car frame through a ball hinge structure; and the translation degrees of freedom at the corresponding restraining positions are released through a sliding block structure. The restraining method of a car frame restraining bending and rotation test provided according to the minimum restraining theory is close to the actual condition of the car frame. Simultaneously, the test is carried out on an independent car frame, therefore, the restraining device is simple in structure and mounting method, thereby completely meeting the requirements of testing accuracy and reliability.

Ultrasonic transducers and methods for detecting oblique flaws in cylindrically-shaped objects using pulse-echo testing are provided. By mounting one or more transducers on a rotary tester for testing manufactured objects such as tubes and bars, offsetting each transducer horizontally from its position if it were to emit a beam that is perpendicular to the object's outer surface, and actuating the transducer so as to emit an angled beam, oblique surface flaws and internal flaws may be reliably detected without reducing inspection speed, significantly adding to transducer cross-talk, or requiring significant additional hardware or processing.

The invention relates to the technical field of engine experiments, in particular to the technical field of helicopter engine over-rotation experiments. The system comprises an engine free turbine speed sensor, a signal processing module, an electronic engine controller and an engine over-rotation fuel bleed valve, wherein the signal processing module comprises two identical sub-circuits, each ofwhich consists of an input limiter, a signal conditioning circuit, a microprocessor, a programmable waveform generator, a signal amplifier and an isolating output end; a rotating speed signal collected by the engine free turbine speed sensor is processed by the signal processing module and is then output to the electronic engine controller; the electronic engine controller controls the turn-on/turn-off of the engine over-rotation fuel bleed valve by analyzing the signal. The test system is simple in use, and has reliable performance and good effect.

The invention provides a vortex induced vibration rotation testing device of an inclined vertical pipe with a movable top end under a step shear flow, belongs to the technical field of marine engineering. The vortex induced vibration rotation testing device comprises a vertical pipe model mechanism, a measurement analysis system platform module, a driving module, a top cantilever module, a cylinder shaft section module, a bottom vertical pipe fixing module, a bottom supporting module and an oscillation module; the vertical pipe model mechanism is fixed between the oscillation module and the bottom vertical pipe fixing module, the oscillation module is fixed on the top cantilever module, the driving module is respectively connected with the cylinder shaft section module and the top cantilever module, the left and right ends of the top cantilever module are respectively connected with the cylinder shaft section module, the measurement analysis system platform module is respectively connected with the vertical pipe model, the top cantilever module, the oscillation module and the bottom vertical pipe fixing module. The testing device provided by the invention can simulate the verticalpipe step shear flow field and vertical pipe top platform movement in an actual size.

The relative position of a test surface is sequentially changed from a reference position where a surface central axis is aligned with a measurement optical axis such that the measurement optical axis is sequentially moved to a plurality of annular regions obtained by dividing the test surface in a diametric direction. The test surface is rotated on a rotation axis whenever the relative position is changed. Measurement light that travels while being converged by a Mirau objective interference optical system is radiated to the rotating test surface, and a one-dimensional image sensor captures interference fringes at each of a plurality of rotational positions. The shape information of each annular region is calculated on the basis of the captured interference fringes at each rotational position, and the shape information is connected to calculate the shape information of the entire measurement region.