Abstract:From the analysis of the measured object, the metrology law, the regulations of the national defense measurement supervision and management and the Chinese people's Liberation Army measurement regulations are compared, and the measurement problems are put forward. Through the analysis of the US military standard MIL-STD-1839D "the calibration and measurement requirements of the United States Department of defense", in order to ensure the consistency of the system operation and accuracy, the research work of metrological design is put forward. Finally, based on the systematic, convenient and rapid measurement guarantee system being always in good state of technology, the metrological design method and design principle are put forward.

Abstract:By combing total enthalpy measurement technique and methods, the principle and characteristic of various total enthalpy measurement methods are presented. The advantage and disadvantage of these methods are analyzed, which include enthalpy probe technique, such as steady enthalpy probe, transient enthalpy probe, mass injection probe and the other enthalpy measurement methods based on energy balance, and optical diagnostics. And the practical experience is given. Finally, the suggestions how to develop the total enthalpy measurement methods better are given based on the above studies.

Abstract:The 3D finite element analysis is used to calculate and analyze the limit load of mitred bend with the longitudinal crack under internal pressure. A finite element model of mitred bend with the longitudinal crack is created, and the influence factors of the limit load under internal pressure are studied. The influence of several dimensionless parameters such as the relative thickness, the relative shapefactor, the relative depth is analyzed. The variation law of the limit load of the longitudinal cracked mitred bend with the shape parameters is summarized. It is found that there is the critical value for each shape parameter. When the parameter exceeds the critical value，the limit load of the structure will decrease significantly.

Abstract:In the process of gyro theodolite calibration, the center of gyro theodolite and observation center of astronomical orientation should be aligned. Its alignment accuracy directly affects the north-seeking precision. In this paper, a double target accurate alignment method based on two parallel collimators is introduced. This method can realize the high precision alignment between the center of gyro theodolite and the observation center of astronomical orientation. At the same time, in order to match the use of this method, a gyro theodolite position adjustment mechanism is introduced. The mechanism can realize horizontal two-dimensional displacement adjustment and high and low altitude adjustment of gyro theodolite. By adjusting the altitude, the center of the gyro theodolite and the observatory center of astronomical orientation are aligned with high precision, thus the measurement accuracy is improved and the calibration requirements of the different types of Gyro theodolite can be met.

Abstract:For solving the problem of long controlling temperature time and low precision by traditional liquid bath based copper strip corrosion testing apparatus. A new copper strip corrosion tester is designed based on metal bath temperature control technology. The apparatus is mainly used to test the corrosion of copper strip at specific temperature. The testing results show that the apparatus has few features including low fluctuate thermal field, even heat and high working efficiency. It is able to be widely used in copper strip corrosion tests

Abstract:Due to many factors in the test site, the calibration coefficient of multi-dimensional force sensor in laboratory has not been applied to the liquid rocket engine test site. The in-situ calibration method for the liquid rocket engine multi-dimensional force measurement device is studied in the paper. The influence factors of vacuum environment, pipeline binding force and temperature drift are also analyzed. The results show that the calibration method can effectively reduce the uncertainty of the multi-dimensional force measuring device, and provide a reference for the in-situ calibration in the field of multi-dimensional force measurement.

Abstract:The basic measurement principle of large scale measurement system with capability of moving target in industrial measurement is summarized. The calibration and evaluation methods of dynamic performance of these measurement systems in dominating standards and guides at home and abroad are analyzed. The similarities and differences of these methods are compared and analyzed. The calibration test results of specialized systems are given. The development direction of the dynamic measuring system is prospected, which provides a reference for the use and calibration of the large scale measuring system.

Abstract:The paper, combining the requirements of layout optimization and stability of large-size measuring equipment during precision measurement of large-scale precision systems ,expounds the structure principle and realization method of stable lifting of large-scale precision measuring platform. Finally, with the help of the omni-directional transfer platform and the carbon fiber synchronous lifting system, the stable support and automatic walking of the large-size measuring device at high altitude are realized. The experimental data show that the stability of the platform is better than that of the theodolite.

Abstract:Aiming at the problem of automatic recognition of target points in locomotive dynamic bounding images, a target point recognition algorithm based on dual-resolution analysis is proposed to solve the problem of searching efficiency for multi-target in high-resolution images. A self-describing vector is proposed to improve the traditional RANSAC algorithm to reduce the interference of background noise. The homography matrix of different target image points is solved. Finally, efficient and accurate automatic recognition and matching of target points can be achieved.

Abstract:In order to solve the problem of precise positioning of the center of a circular reverse reflection mark in the calibration of the reference scale of industrial photogrammetry system, a positioning scheme of the center of a circular reverse reflection mark based on microscopic vision and image processing was proposed. The composition and principle of the center positioning system are introduced. According to the reflective characteristics of the reflective mark and its image characteristics under the microscope, the image preprocessing, feature extraction and image processing methods of the center positioning of the mark are analyzed. The magnification of the image, the position of the mark image in the field of view, illumination and other factors which may affect the results of the mark center positioning are tested and analyzed. It is of great significance to standardize the calibration process of the reference scale.

Abstract:In order to solve the problem that the laser tracker cannot satisfy the requirement of continuous automatic measurement at present, a scheme of using manipulator to grab the target ball is proposed. By establishing the system model and transforming the unified coordinate system, the position and attitude of the end of the manipulator can reach the position and attitude of the measured target point, and the continuous automatic measurement made by a laser tracker can be realized by using the trajectory planning of the manipulator. Finally, the feasibility of the scheme is verified by Matlaba simulation.

Abstract:Aiming at the problem of evaluating the instantaneous velocity response of turntable, a method of evaluating the dynamic response of turntable based on velocity triangular wave signal is proposed. This method uses the envelope distribution of deviation to estimate the deviation range of acceleration and speed of the turntable system. Experimental results show that the method is feasible.