145 results about "Sinusoidal vibration" patented technology

The invention relates to a focusing and levelling device with an expandable measuring range, which comprises a light source, an optical projection unit, an optical receiving unit, an optical modulation unit, a receiving silt surface, a photoelectric detector and a control unit, wherein the optical projection unit receives light emitted by the light source and irradiates the light to the surface of a measured silicon wafer to form a measuring light spot matrix W; the optical receiving unit receives the light reflected by the measured silicon wafer; the optical modulation unit is provided with a scanning reflector which makes sinusoidal vibration during levelling measurement; a silt matrix S of silts corresponding to each light spot on the silicon wafer is formed on the receiving silt surface, and the light spots reflected by the scanning reflector are imaged on the receiving silt surface; the photoelectric detector converts a light energy signal passing through the silts into an electrical signal; the control unit analyzes the electrical signal outputted by the photoelectric detector; and an expanding silt positioned on the edge of the silt matrix is also formed on the receiving silt surface and is used for expanding the measuring range of the focusing and levelling device. The invention also discloses a focusing and levelling method using the device.

The invention provides a method and a system for predicting random vibration life of a PCB solder point. Based on a sinusoidal vibration test and harmonic response simulation analysis, a stress-life curve of the PCB solder point is determined; According to a stress-time curve of a random vibration fatigue dangerous part of the PCB solder point or a strain-life curve of a PCB, the cycle number, stress amplitude and mean distribution of the random vibration fatigue dangerous part of the PCB solder point are determined with a rain-flow counting method; the random vibration fatigue loss of the PCB solder point is determined; and finally based on a Miner rule, according to the random vibration fatigue loss of the PCB solder point, the random vibration life of the PCB solder point is predicted. The whole process is based on precise data processing, the operability is strong, and a stress and time response signal is subjected to cycle number statistics and sorting with the rain-flow counting method, so that the data acquisition accuracy in the process for predicting the random vibration life of the PCB solder point is ensured.

The invention provides a device for wind tunnel dynamic derivative pitch vibration test. The device comprises a support mechanism, a parallel-double-crank mechanism and a limit detection module, the support mechanism is a base body for mounting of the device, the parallel-double-crank mechanism realizes and transfers pitch sinusoidal vibration motion, and the limit detection module provides alarm for excess of mechanism rotational stroke. After vibration frequency and amplitude are set and a specific vibration curve is outputted by a servo motor, an aircraft model is driven to perform pitch vibration through the parallel-double-crank mechanism mounted on the support mechanism, and in the process, the limit detection module provides limit and protection for the mechanisms.

The invention discloses a virtual sinusoidal vibration testing method for spacecrafts, which comprises a simulation model building step, a parameter setting step for virtual sinusoidal vibration testing, a transfer function computing step, a testing driving signal generating step and a virtual sinusoidal vibration testing step. By the virtual sinusoidal vibration testing method, all key links of real vibration testing of the spacecrafts are taken into consideration sufficiently, transfer functions of a vibration platform testing control system and a plurality of forming systems are integrated, and reality and accuracy of the conventional open-loop numerical method are evidently improved by the closed-loop computing method.

The invention discloses a method for preventing a peritectic steel continuous casting blank from generating cracks, which comprises a step of continuously casting by using a continuous casting machine. The method is characterized in that: in the continuous casting process, protective slag of which the alkalinity is 1.3 to 1.5 and the viscosity is 0.03 to 0.07Pa.s at 1,300 DEG C; a crystallizer adopts sinusoidal vibration, and has the vibration frequency of 150 to 198min<-1> and the vibration amplitude of 5.0 to 8.0mm; and the water volume of the crystallizer is reduced by 5 to 10 percent. The method effectively solves the problem of cracks on the surface of the peritectic steel continuous casting blank, improves the quality of the casting blank, and reduces casting blank clearing quantity and waste quantity.

The invention provides a decoupled three-degree-of-freedom forced vibration system for a bridge section model. The system comprises an outer vibration system, an inner vibration system, a model support system and a detection system, wherein the outer vibration system and the inner vibration system are symmetrically arranged on the two sides of a wind tunnel; the model support system is connected with the outer vibration system and the inner vibration system respectively, and is also connected with the detection system; the detection system is connected with the bridge section model through an inner model connecting plate and an outer model connecting plate; and the outer vibration system and the inner vibration system synchronously vibrate under the drive of a servo motor to realize the synchronous three-degree-of-freedom sinusoidal vibration of the bridge section model. By the system, the transverse motion, vertical motion and torsional motion of the model in a section are realized, and are combined into totally seven kinds of motion with higher amplitude, and each kind of motion is independent simple harmonic motion with adjustable frequency, amplitude and phase. The system has the advantages of capability of acquiring three components of force of the bridge section model in real time, and data accuracy.

The invention discloses a non-sinusoidal vibration method for a continuous casting crystallizer. According to the technical scheme, the non-sinusoidal vibration method for the continuous casting crystallizer comprises controlling a driving device of the continuous casting crystallizer to enable the continuous casting crystallizer to perform non-sinusoidal vibration according to speed waveforms which are confirmed according to following functions in every vibration period with the driving of the driving device; enabling the vibrating process of every vibration period to be formed by seven sections; enabling the crystallizer to move according to a given vibrating method due to control of the driving device of the crystallizer and achieving the non-sinusoidal vibration. The non-sinusoidal vibration method for the continuous casting crystallizer has the advantages of being smooth and continuous in displacement and speed waveform, having no mutation in accelerated speed, not generating rigid and flexible impact and having good waveform dynamic characteristics and enabling the largest accelerated speed of the movement of the crystallizer to be served as a quantity which is reflected in the waveforms, enabling the quantity to be allowed setting according to actual conditions and to be invariant, increasing waveform deflection rate, enabling non-sinusoidal vibration of the crystallizer to be enhanced but the accelerated speed of the vibration of the crystallizer to be kept constant and guaranteeing movement smoothness of the crystallizer.

The invention discloses a forecasting system for a high-magnitude test condition of a sinusoidal vibration test for spacecrafts; the forecasting system comprises the following six modules: (1) a low-magnitude (feature-level) sinusoidal vibration test condition and test data input module; (2) a high-magnitude test condition input module; (3) a sunk condition criterion, part and component one-machine test condition input module; (4) a high-magnitude test condition forecasting and analyzing module; (5) a high-magnitude test condition displaying and adjusting output module; and (6) a test condition and analysis management module. The forecasting system provided by the invention can be directly applied to the vibration test of the spacecrafts and can be used for forecasting the high-magnitude test condition in combination of a low-magnitude (feature-level) sinusoidal vibration test condition and test data according to a given sunk condition criterion and a part and component one-machine test condition. The forecasting system is convenient for condition design and improves the effectiveness of tests and efficiency.

The invention discloses a multi-frequency synthesized vibration test device. The multi-frequency synthesized vibration test device comprises a system controller, a motor, a speed adjusting device and a vibration platform, wherein the vibration of the vibration platform at least comprises the vibration of two frequency components; the vibration of each frequency component is generated by an eccentric rotation mechanism with different rotating speeds; multiple vibration is synthesized through a mechanical lever in a pair combination mode; the vibration of each frequency component represents one section of frequency range in a transportation vibration environment; when the rotating speed of the motor is adjusted, each vibration frequency component performs synchronous variable frequency scanning in the frequency section represented by each vibration frequency component; a vibration device can perform fixed frequency and variable frequency tests on samples; the simulation degree of the vibration device on the transportation vibration environment is similar to that of a random vibration test; the vibration device is the optimized combination of two schemes of sinusoidal vibration and random vibration; and after two vibration platforms with complementary phase positions are provided, the influence of the test device on the ambient environment is reduced.

The invention provides a fixed frequency calibration test method of spacecraft vibration. The method comprises the following steps that: a corresponding relation between a support reaction force per unit length and a strain of a spacecraft root is determined, wherein the support reaction force per unit length is generated by the spacecraft during a sinusoidal vibration test, and an auxiliary basis is provided for determination on a concave downward condition of a main frequency range during the sinusoidal vibration test of the spacecraft; more particularly, at an off-resonance range of the spacecraft, by using a lowest working frequency that is allowed by a vibrating table and is normally from 2 to 5 Hz, sinusoidal excitation with a fixed frequency is carried out on the spacecraft under a certain order. After test evaluation is completed, the test method can be applied to vibrating tests of various spacecrafts, so that rationality and effectiveness of the test can be determined. According to the invention, problems that are common in the vibrating test process of a spacecraft can be solved, wherein the problems include a problem of overloading or underloading; and beneficial effects are as follows: the test is reasonable and reliable; the method can be realized simply; and the adaptability is strong and the like.

The invention discloses a waveform adjustable non-sinusoidal vibration method of a continuous casting crystallizer, which belongs to the technical field of continuous casting. The method is characterized in that a drive device for controlling the continuous casting crystallizer drives the continuous casting crystallizer, in every vibration period, to conduct non-sinusoidal vibration according to a track determined by the following vibration displacement procedure function: a formula (1) is as described in the specification, wherein S(t) is the displacement of the non-sinusoidal vibration; h is the stroke of the non-sinusoidal vibration; omega is angular velocity of the non-sinusoidal vibration, t is time of the non-sinusoidal vibration, ai is a technology constant correlated to the sinusoidal vibration and is not correlated to the stroke h and the angular velocity omega; and i is a term number. According to the method, when the track determined by the vibration displacement procedure function in a quadrinomial can ensure that the waveform does not distort when the rate of deflection is 0-37.5%; and the velocity, accelerated velocity and accelerated velocity change of the non-sinusoidal vibration of the crystallizer are all monotonous and continuous, so that the impact on equipment due to flutter in the course of operating is avoided, and the operation of the equipment is more stable and reliable.

The invention discloses a non-sinusoidal waveform generator used for mold oscillation, comprising a signal input module, a waveform generation module and a waveform output module, wherein the signal input module is used for inputting the amplitude, the frequency and the deviating rate of the non-sinusoidal waveform; the waveform generation module is used for receiving the amplitude, the frequency and the deviating rate of the signal input module to generate corresponding waveform; and the waveform output module is used for outputting the waveform generated by the waveform generation module to an oscillation controller. The waveform generation module executes the following function: s is equal to Ah x*(-delta)<m-1>Sin(m omega t). The non-sinusoidal oscillation waveform generated by the waveform generator can greatly improve the non-sinusoidal deviating rate, and avoid oscillation during the motion process of the equipment so as to lead the equipment to run smoothly; and the non-sinusoidal oscillation waveform can further greatly improve the negative slip time and the effective control range of the negative slip rate, minimize the friction force between the molten steel and the casting mold, reduce oscillation marks on the surface of casting blank and improve the surface quality of the casting blank.

The invention discloses a multi-dimensional sinusoidal vibration control method and control apparatus. The apparatus comprises an upper computer, a PXI real-time controller, a data acquisition card, an acceleration sensor and a displacement sensor. The method includes the steps of system parameter setting, system self detection, system identification, sinusoidal vibration frequency starting, sinusoidal frequency sweeping, and test completing and stopping after frequency sweeping, thereby realizing control on the control apparatus. According to the invention, the control is stable; the apparatus has good sinusoidal vibration control capability from one dimension to six dimensions and is suitable for the multi-dimensional sinusoidal vibration control or sinusoidal test. In addition, different initial phases can be set for different control dimensions to form the sinusoidal vibration or motion under several kinds of combination modes. Meanwhile, an amplitude identification technology based on combination of an FFT and a filter, a semi-sinusoidal-window stable frequency starting technology, a multi-dimensional driving amplitude on-line updating method, and an acceleration and displacement mixed control method are used for obtaining a satisfying testing effect. Moreover, the apparatus has advantages of simple system, less modules, easy installation, and convenient maintenance.

Embodiments of the present invention provide a method for non-contact detection techniques of mechanical vibrations utilizing a radio frequency system incorporating multiple carrier wavelengths. The new detection method measures multiple harmonic pairs at a carrier frequency and improves the detection accuracy and reliability by first inspecting the Bessel function coefficient of each harmonic and then determining the harmonic amplitude. The original mechanical vibration can then be reconstructed. Embodiments can be used to realize sensing of complex non-sinusoidal vibrations using a wavelength division sensing technique and allow non-contact detection through walls, smoke, fog or other low visibility environments with the advantage of longer range detection and easy integration at a low cost.

The invention discloses a direct-drive crystallizer vibration generating device which comprises a vibration platform, wherein the vibration platform is connected with a connecting rod; the connecting rod is connected with a linear motor; the linear motor drives the connecting rod to drive the vibration platform to move; the linear motor is connected with a control component; and the control component controls the moving mode of the linear motor. The invention also discloses a non-sinusoidal vibration method realized by the device. The vibration formula is shown in the specification, wherein Tis the vibration period, tA is the rising half period, tC is the falling period, f is frequency, t is time, h is amplitude, and alpha is the deviation rate. According to the invention, a transmission system is simplified and has a compact structure, and other mechanical structures of the existing traditional mechanical type crystallizer vibration device do not need to be changed; the motor is directly driven to operate up and down, and the service life is prolonged; and the entire structure has the advantages of large bearing capacity, strong impact resistance, high reliability and the like.

The invention relates to a high-precision high-acceleration low-frequency sinusoidal vibration system which comprises a rotating motor, a crank disc, a crankshaft, a horizontal rolling guide rail, a vertical rolling linear bearing, an upright post, a worktable, a balance weight and a position sensor, wherein a left guide post and a right guide post are arranged on a base; a left linear bearing and a right linear bearing are respectively arranged on the left guide post and the right guide post and can move up and down on the guide posts; two ends of a transverse beam are respectively connected with the left linear bearing and the right linear bearing; the horizontal rolling guide rail is fixedly connected to the transverse beam; a horizontal guide rail slide block can move from left to right on the horizontal rolling guide rail; and the upright post and the worktable are arranged on the transverse beam. According to the mechanical system, high-precision and high-acceleration low-frequency sinusoidal vibration can be realized, the defects of a centrifuge test are overcome, the flexibility of research trial is improved, the problems that a low-frequency section of the conventional vibration table is low in vibration amplitude and vibration frequency precision, the testing requirements of a high-precision inertia type instrument cannot be met and the like are solved, and a high-order error item coefficient of the inertia type instrument is tested.

The invention provides a non-sinusoidal vibration method of a continuous casting mold. The non-sinusoidal vibration method includes steps of controlling a driving device of the continuous casting mold so that the continuous casting mold vibrates non-sinusoidally in line with eight-stage speed determined as the following eight-stage speed function in each vibration cycle; introducing a new vibration control variable, namely the constant-speed duration factor m, increasing the control means for the waveforms to facilitate the vibration control according to the actual conditions. The casting speed and vibration waveform can be combined for different billet speed, and different vibration schemes can be designed; the consumption of casting powder can be increased, continuous casting lubrication is facilitated, and friction, cracks and binding are reduced. Therefore, the vibration speed of the crystallizer is equal to the extension of the casting speed, and the uniform outward heat transfer of the continuous casting and stable growth of the initial base are facilitated.

The invention relates to the technical field of continuous casting, in particular to a method for preventing longitudinal cracks on the surface of a sub-peritectic steel casting blank. The method comprises the following steps of: in a continuous casting process, adopting casting powder, the viscosity of which is 0.08-0.14 Pa.s when the alkalinity of the casting powder is 1.2-1.4 and the temperature of the casting powder is 1300 DEG C; reducing the water quantity of a crystallizer by 5%-10%; and controlling the water inlet temperature of the crystallizer to be 28-35 DEG C, wherein the crystallizer is in non-sinusoidal vibration. According to the method for preventing the longitudinal cracks on the surface of the sub-peritectic steel casting blank provided by the embodiment of the invention,the cracks are prevented from occurring on the surface of the sub-peritectic steel casting blank by adopting the casting powder, the viscosity of which is 0.08-0.14 Pa.s when the alkalinity of the casting powder is 1.2-1.4 and the temperature of the casting powder is 1300 DEG C, reducing the water quantity of the crystallizer by 5%-10% and controlling the water inlet temperature of the crystallizer to be 28-35 DEG C. As the lubrication effect of the casting powder is reduced after the alkalinity of the casting powder is increased, the non-sinusoidal vibration and the high-vibration frequencyand small amplitude vibration mode are adopted to reduce the negative slip time and improve the lubrication, and the longitudinal cracks on the surface of the sub-peritectic steel casting blank can beeffectively prevented.

The invention relates to a method for controlling fine cracks on the surface of a sub-peritectic steel bar. The method is characterized in that the relation between a peritectic reaction body shrinkage rare (Gamma) and the carbon content of molten steel at a brittleness temperature zone (LIT-ZDT) is calculated and analyzed through a phase diagram, the carbon content with the shrinkage rate of a peritectic reaction body being less than 0.004 is preferentially selected to be the component control range during smelting of sub-peritectic steel, and the content of sulfur in the molten steel is controlled to be less than 0.005%; the superheat degree of the molten steel during continuous casting is controlled to be 15-25 DEG C through strict refining temperature control; in the case of continuouscasting protective slag, the protective slag which is high in alkalinity, high in viscosity, high in melting temperature, high in melting speed and high in crystallization rate is adopted; the continuous casting pulling speed control is determined according to the peritectic reaction intensity, wherein the pulling speed is less than or equal to 0.002/ Gamma(m/min); a weak cooling mode is adoptedfor cooling and secondary cooling of a crystallizer; the conicity of the crystallizer is controlled to be 1.15-1.25%/m; and the vibration of the crystallizer adopts a non-sinusoidal vibration mode. According to the method, the fine cracks on the surface of the sub-peritectic steel bar can be successfully controlled, the quality and percent of pass of the surface of the sub-peritectic steel bar areremarkably improved, and the production cost is reduced.

The invention relates to a method for eliminating irregular vibration marks of a high-carbon steel billet surface. Under the premise that original continuous casting process parameters are not changed, physical and chemical parameters of casting powder are reasonably and accurately selected, the quaternary alkalinity of crystallizer casting powder, namely R{w(CaO)+w(MgO)}/{w(SiO2)+w(Al2O3)}, is 0.64-0.70; the melting temperature Tm (DEG C) of the casting powder and the lowest liquidus temperature T1(DEG C) of casting steel types meet a relationship that Tm is equal to or larger than T1-450, and equal to or smaller than T1-420; the viscosity eta (Pa.s. 1300DEG C) of the casting powder and the casting speed v (m/min) meet the relationship of eta= 0.4/v + 0.02; and besides, the sinusoidal vibration parameters of a crystallizer are reasonably and accurately set, the vibration frequency f (times/min) and the casting speed v (m/min) of the crystallizer meet the relationship of f=-16v<2>+23v+220, and the amplitude s (mm) and the casting speed v (m/min) of the crystallizer meet the relationship of S=-0.8v<2>+2v+3.8.Through the adoption of the production method disclosed by the invention, the consumption quantity of the high-carbon steel casting powder can be stably and reasonably controlled, the lubricating effect between casting blank and the crystallizer is guaranteed, the irregular marks of the high-carbon steel billet surface are eliminated, the surface quality of the casting blank is stably controlled, and the quality of finished products is improved.

The invention provides a vibration method stay cable force measuring method by employing a sinusoidal vibration exciter and a video instrument with the introduction of vibration displacement, and belongs to the technical field of civil engineering. The method includes: firstly, estimating the fundamental frequency range of the cable, installing the vibration exciter at the position of half of thelength of the cable, enabling the vibration exciter to perform frequency sweeping excitation in the estimated fundamental frequency range, recording the exciting frequency at the moment as the cable self-vibration frequency f1 when resonance occurs to the cable, observing and recording the vibration displacement [phi]i of a certain section of the cable at a certain instant by employing the video instrument, and finally calculating the cable force by employing a vibration mode cable force recognition model. According to the method, a value calculating method is proposed by employing a certain self-vibration frequency f of the cable and several vibration mode components of corresponding vibration modes, and the pulling force of the stay cable can be recognized in the condition of unknown boundary conditions.

The invention relates to a non-stationary vibration signal generating method used in an acceleration test. The non-stationary vibration signal generating method comprises the steps of: classifying anddecomposing original vibration acceleration signals into Gaussian vibration signals and sinusoidal vibration signals, and synthesizing the Gaussian vibration signals and sinusoidal vibration signalsinto a new non-Gaussian vibration signal. The non-stationary vibration signal generating method restores the non-Gaussian vibration characteristics and intrinsic acceleration transient of random vibration during the road transportation process. Through separating an acceleration transient signal independently during the decomposition process of the original vibration signals, the newly generated accelerating signal can be used in the vibration acceleration test. The non-stationary vibration signal generating method ensures that the duration and vibration magnitude of the transient accelerationsignal are not subject to change during the compression process of vibration testing time.

The invention discloses a strain gauge dynamic calibration method and device based on non-contact scanning measurement, and belongs to the field of metering test. The implementation method comprises the steps that the output of a controller of a vibration exciter is adjusted to reach a required vibration frequency, and the output of the power amplifier of the vibration exciter is adjusted to reacha required amplitude; a cantilever beam is kept in a sinusoidal vibration state with the stable frequency through the vibration exciter; N measuring points at equal intervals are selected on the surface of the cantilever beam in the axial direction of the beam, and deflection measurement is performed on the surface of the cantilever beam in a forced vibration state; the peak deflection curve of the surface of the cantilever beam is fit according to the obtained deflection state of each measurement point; the peak deflection curve is converted into a strain peak curve; and a calibrated straingauge is installed in the calibration area of the cantilever beam, and the output value of the calibrated strain gauge is compared with a standard strain value, thereby achieving the dynamic strain calibration. The invention further discloses a strain gauge dynamic calibration device based on non-contact scanning measurement. The structure is simple, and the operation is easy.