214results about How to "Meet the requirements of measurement accuracy" patented technology

The invention relates to a static and dynamic acceleration tester, comprising a computer, a motion controller, a static acceleration generator, a dynamic acceleration generator, and a portable braking-ability testing instrument, wherein, the static acceleration generator mainly comprises a stepping motor, a photoelectric encoder, and an angular platform; the dynamic acceleration generator mainly comprises a servomotor and a rotation platform. The invention has the advantages of static and dynamic testing method, convenient installation, simple and quick testing process, high degree of automation, and ability of satisfying measuring precision requirement of related national standard, and calculating, memorizing, inquiring and printing the test result.

The invention discloses a landslide MIMO radar monitoring system and monitoring method. Emitting and receiving antennas of the system are an MIMO radar antenna array. Emitting and receiving time-sharing selectors are connected with emitting and receiving antenna array elements respectively. A system synchronization control unit is connected to the emitting and receiving time-sharing selectors through an antenna time-sharing control unit. The monitoring method is characterized by carrying out MIMO antenna array time-sharing emission and step frequency continuous wave signal reception; carrying out inverse Fourier transform and distance compression on echo data, carrying out phase discontinuous correction on radar echo data, calculating time delay compensation factor and carrying out beam forming method azimuth focusing to obtain a high-resolution complex image; carrying out continuous monitoring to obtain a plurality of complex images and forming complex image pairs; and calculating differential interference phase after complex image pair registering and extracting deformation value and carrying out early warning. According to the landslide MIMO radar monitoring system and monitoring method, non-contact remote monitoring is achieved, monitoring range is wide, azimuth resolution ratio is high, real-time performance is high, data acquisition is quick, system device is light and portable, and layout is adjustable.

The invention provides a wMPS network layout optimizing method based on simulated annealing particle swarm optimization. A measuring station layout optimizing aim is one of important aims in use of a wMPS. The method aims at achieving the aim that due to the optimized measuring station layout, a to-be-measured region can be comprehensively covered with certain cost, and the requirement for measuring accuracy can be met. According to the wMPS network layout optimizing method, a reasonable positioning error model is built, a multi-objective optimization function is defined, and the network layout of the wMPS is optimized with the simulated annealing particle swarm optimization. The measuring-station network optimized layout aim of the wMPS in engineering application is effectively achieved through the rapid convergence capacity of the particle swarm optimization and the global convergence capacity of the stimulated annealing algorithm. Along with increasing of the number of measuring stations, the method has good expansibility and can provide a novel method with high adaptability for the multi-station networking measuring layout optimizing aim based on an angle intersection principle, and important theoretical value and practical significance are achieved.

The invention discloses a calibrating method for a CCD (Charge Coupled Device) imaging lateral laser radar. The method comprises the following steps of: enabling an optical axis (1) of a CCD camera to be vertical to the plane of a calibration table (2), firstly acquiring a CCD image of the calibration table (2) by use of the CCD camera (3), and then calculating the offset angle (alpha) and angle width (d alpha) of each pixel according to a table number in the CCD image of the calibration table (2) and a pixel number with a same dimension as the table number increment in the table; and after placing the CCD camera (3) at the lateral adjacent part of an emitted light beam (5) of the laser radar, firstly determining the vertical distance(D) between the CCD camera (3) and the emitted light beam (5) of the laser radar by adopting a three-point positioning method, then substituting the offset angle (alpha) and angle width (d alpha) of each pixel as well as the vertical distance (D) between the CCD camera (3) and the emitted light beam (5) of the laser radar into a lateral laser radar equation P(alpha)=P0KA/D *TtTrbeta(alpha)dalpha, and performing inversion calculation by use of the offset angles (alpha), the angle widths (d alpha) and the vertical distance (D) so as to obtain atmospheric parameters. The calibrating method disclosed by the invention is high in measurement accuracy and wide in application range, and can be widely used for measuring the spatial distribution of atmospheric aerosol of a surface layer.

The invention discloses a leveling method suitable for a compound level gauge. According to the leveling method, an angle i of the compound level gauge for dual observing can be accurately measured and adjusted according to FORMULAE (details in description), so as to meet a measurement accuracy requirement; and then, steps b1, b2, b3 and b4 are carried out to carry out two-point altitude difference measurement. The steps b1, b2, b3 and b4 are as follows: b1. respectively measuring an altitude difference between Pk and Pk+1 by utilizing a compound level gauge A and a compound level gauge B; b2. calculating the difference epsilon among the altitude differences between the Pk and the Pk+1 which are measured by utilizing the compound level gauge A and the compound level gauge B; b3. judging whether the absolute value of the epsilon exceed a limit, if the absolute value of the epsilon is within a tolerance, and carrying out the step b4, and if the absolute value of the epsilon is out of tolerance, repeating the steps b1, b2 and b3; and b4, allowing the mean value of the altitude differences between the Pk and the Pk+1 which are measured by utilizing the compound level gauge A and the compound level gauge B as a measured value.

A survey station optimization deployment problem is one of important problems in use of a spatial measurement positioning system. The present invention provides a survey station layout intelligent optimization method of a spatial measurement positioning system, so that an optimized survey station layout can fully cover a tested area under certain costs and a requirement of measurement accuracy can be met. According to the present invention, a proper positioning error model is established from three aspects of constraint analysis, optimization objective, and optimization means, a multi-goal optimizing function is defined, and survey station layout optimization of the spatial measurement positioning system is implemented by using a practical intelligent optimization algorithm. According to the survey station layout intelligent optimization method of a spatial measurement positioning system, a survey station network optimization deployment problem of the spatial measurement positioning system in an engineering application is effectively resolved. As a quantity of survey stations increases, the method has good expansibility, provides a new method for a multi-station networking measurement layout optimization problem based on an angle intersection principle, and has important theoretical value and practical significance.

The invention discloses an open-close type current and voltage transformer which comprises a current transformer and a voltage sampler, wherein the voltage sampler is mounted on one side of the current transformer through a T-shaped bulge and a T-shaped groove on the side surface of the current transformer, and the relative positions of the current transformer and the voltage sampler can be determined through two fixing pieces and the bulge on the current transformer. As an upper housing and a lower housing of the current transformer comprise mounting holes which can be fastened by using nuts and screw rods, thereby being convenient to enable the upper housing and the lower housing to form a closed combined whole during the use. The whole current and voltage transformer can be combined by adopting the screw rods and the nuts, thereby simultaneously having the function of sampling voltage signals. A groove structure is adopted at the joint of two C-shaped iron cores and matched with a resin housing with orthogonal grooves, the connection is reliable, the good closing of a magnetic circuit is ensured and the requirements on the measurement precision can be met.

The invention discloses an underwater high-precision measurement and control system and method for pipe abutment in the construction of an immersed tunnel. The system comprises multiple groups of receiving / emission ultrasonic sensors, an industrial PC control platform, a serial / wireless network communication system, a command room PC control and display platform. The multiple groups of receiving / emission ultrasonic sensors are connected with the industrial PC control platform through coaxial cable; and the industrial PC control platform and the command room PC control and display platform are connected through a serial / wireless network communication system. The invention also provides a measurement and control method. The measurement system provided by the invention has the advantages of low cost, high precision, strong adaptability, high degree of intelligence and good reliability, and can effectively solve the problem of high-precision measurement and control of underwater pipe abutment in the construction of immersed tunnel.

The invention discloses a space general position and orientation measurement standard of a machine vision measurement system, and aims to solve the problem that verification on measuring results of objects in general positions and orientations in space of the machine vision measurement system cannot be realized. A three-way linear guide rail and a two-way curved guide rail are utilized to enable a standard target to reach optional position angles in the space. The system has the advantages of simple structure, high accuracy in measurement, small accumulative errors, completeness in functions, convenience in operating and the like. The system comprises a position adjusting part (A) and an orientation adjusting part (B). By the aid of the space general position and orientation measurement standard, the verification on space general position and orientation measuring results of the machine vision measurement system is realized.

The invention discloses a camera three-dimensional truss calibrating target for an automotive visual detection system. The camera three-dimensional truss calibrating target for the automotive visual detection system aims at solving the problems that the existing three-dimensional calibrating object is large in size and complex in machining, cannot obtain three-dimensional data points of spatial general positions in a space coordinate system and is difficult to achieve site calibrating which is high in requirement for practicability. The camera three-dimensional truss calibrating target for the automotive visual detection system is mainly formed by target balls (1) and connecting rods (2). The camera three-dimensional truss calibrating target for the automotive visual detection system has the advantages of being simple in structure, high in detection accuracy, small in accumulative error, complete in function, simple in operation, easy to install, strong in universality, low in cost and reliable in performance and satisfying an automotive detection industry requirement for visual detection of an automobile body.

Disclosed is a method for embedding optical fiber sensors in an aircraft cabin. A plurality of longitudinal grooves and a plurality of transverse grooves are formed in the surface of the aircraft cabin in advance, longitudinal cabin inlets are reserved in the two ends of the aircraft cabin, transverse cabin inlets corresponding to the transverse grooves one to one are formed in the circumference of the aircraft cabin, the multi-path optical fiber sensors are distributed in the multiple longitudinal grooves and the transverse grooves, the grooves are filled with glue and fixed, and then the optical fiber sensors can be embedded in the surface of the aircraft cabin. The multi-path optical fiber sensors pass through the corresponding longitudinal cabin inlets and the transverse cabin inlets, then enter the aircraft cabin, are gathered at the two ends of the cabin to form optical fiber bundles, are integrated to an optical fiber connector and then are connected with an information collection device or communicated with an adjacent cabin. By the method, the optical fiber sensors can be embedded in the surface of a single-cabin or multi-cabin butt joint type aircraft, an optical fiber sensing and detecting network is achieved, the mechanical property and damage situations of the aircraft cabin can be monitored comprehensively, and the method has the advantages that reliability is high and operation is easy.

The invention belongs to the technical field of multi-channel receivers of synthetic aperture radar systems, and discloses a method and a device for designing a multi-channel receiver of a double-basesatellite-borne SAR system. According to the method and the device for designing a multi-channel receiver of a double-base satellite-borne SAR system, eight receiving channels are included, and a +/-5V power supply and a serial control signal are provided for each radio frequency receiving channel through a power supply conversion unit and a control distribution unit in a unified mode. Each radiofrequency receiving channel can independently complete the functions of low noise amplification, MGC, intermediate frequency amplification, balanced phase shift compensation output and the like of radar echo signals, every two receiving channels are output through cross backup, and imaging indexes of a whole radar system are influenced by amplitude-phase consistency performance indexes of every two receiving channels. The method and the device for designing a multi-channel receiver of a double-base satellite-borne SAR system have the outstanding advantages that: 1, the multi-channel receiveris adopted to better meet the working requirements of a new system of high-resolution and wide-swath satellite-borne SAR; and 2, the amplitudes and the phases of the receiving channels are compensatedthrough an equalization phase shifter and a microstrip power division power combiner, the amplitude consistency among the channels reaches 0.4 dB, and the phase consistency reaches 2 degrees.

The invention discloses a phase pulse-type laser range finding method. The method includes the following steps: S1, obtaining a first phase difference [phi]F1 of various frequency components among first emission pulse signals with the frequency of F1MHz, and obtaining a second phase difference [phi]F2 of various frequency components among second emission pulse signals with the frequency of F2MHz; S2, conducting difference operation on the first phase difference and the second phase difference, and obtaining a phase difference [phi]0 of target modulation frequencies, wherein [phi]0=[phi]F2-[phi]F1; and S3, substituting [phi]0 into a range finding formula L=C/2[phi]0, and obtaining a corresponding laser range finding distance L. According to the method, a duty ratio of both the first emission pulse signals and the second emission pulse signals is 5%-10%, 5MHz<F1<20MHz, and 5MHz<F2<20MHz. The method has the advantages that the cost is low, the anti-interference capability is high, and the measuring speed is fast.

The invention discloses a correction method of flow measurement properties of a single-track ultrasonic water meter. The correction method comprises the following steps: 1) respectively calculating surface average flow speeds when a reynold number is an upper limit value of a laminar flow state, a lower limit value of a turbulent flow state and the upper limit value of flow measurement of the water meter; 2) calculating linear average flow speeds corresponding to the surface average flow speeds according to an existing known calibration equation; 3) establishing fitted linear correction equations during the laminar flow state, a transition flow state and the turbulent flow state; and 4) measuring the linear average flow speed Nu through the ultrasonic water meter, comparing Nu with V1 and V2 and performing correction according to the appropriate fitted linear correction equation according to a comparison result. According to the correction method disclosed by the invention, the correction is performed on the flow measurement properties of the ultrasonic water meter by setting the simple linear correction equations under the different flow speed distribution states, and the calculation is simple and fast; and furthermore, the requirements on measurement accuracy of the ultrasonic water meter within a whole flow measurement range can be met by fine adjustment of 2-3 flow points under an actual flow state, and the effects of simplicity, convenience and accuracy can be also achieved.