Papers by Keyword: Laser Measurement

Abstract: The previous research confirms that the shape of measurement objects influences the measurement results, and the influences can be reduced by aligning the normal of the measurement object with the laser projection axis when using a laser displacement meter for 3D shape measurement [1]. but when the laser projection axis aligns with the normal of the measurement object, calculated based on the design value, the influence of the tilt of the measurement object is omitted if the measurement object has machining or mounting errors. This paper proposes a high-precision shape measurement method for on-machine measurement that considers machining errors and validated its effectiveness.

Abstract: Aiming at the problem of the complicated process, the low precision and efficiency of crack detection and key geometric feature of the circular saw blade, the quality detection system of the circular saw blade based on the nondestructive testing and laser measurement technology is studied. By using the laser measurement technology and optimizing the data processing method, the face runout, the thickness of the circular saw blade are measured. The crack defects in the tooth root region of the circular saw blade are detected by eddy current nondestructive testing technology. The system achieves the radial detection of 1mm radial sawing, the detection accuracy of the round beating is> 0.03mm, and the thickness measurement accuracy is> 0.005mm.

Abstract: Precision of filter rod circumference is an important performance index of the cigarette manufacturing. The forming mechanism of filter rod, equipment vibration and other interference factors all lead to fluctuations of precision of filter rod circumference which can affect the precision of the cigarette. The existing KDF2/3 filter rod making machine which has the characteristics of compact structure (small space dimension), high speed (300 m/min) and discrete control of precision of filter rod circumference is the core equipment of filter rod production. This paper puts forward four kinds of online real-time detection schemes on precision of filter rod circumference which are Aomeijia’s many groups of detectors scheme, Keyence’s contour detection scheme, high precision measuring diameter instrument detection scheme using multiple sets of KD series meter and the 360 degrees rotating survey meter. On the basis of extensive analysis and experimental validation, Aomeijia’s four-way diameter measuring instrument scheme is optimal. The scheme applies laser to non-contact high speed scan on key radial diameter size of filter rod which achieves 0.001mm high precision detection.

Abstract: Traditional tooling for aircraft skin will produce a large clamping deformation of the inadequacies in the assembly process, designed a vacuum suction cup flexible assembly tooling, that tooling using vacuum suction force to clamp the workpiece in the assembly process, greatly reduces the amount of deformation of the workpiece. In order to accurately grasp the new tooling excellent performance in terms of adsorption deformation, through the establishment of a laser measuring device test platform, we conducted a large number of studies of vacuum adsorption deformation experiment on different thickness of the workpiece,has been obtained the workpiece adsorption deformation rate range under the flexible tooling system, as well workpiece thickness, sucker adsorption, the number of anchor effect on the adsorption deformation rate of the workpiece, and verify the reasonableness of the flexible assembly tooling.

Abstract: Currently, the chemical pollution of water detection is mainly based on optical method. However, the optical detector is easily restricted by light and weather conditions. Optical measurement can be set on the target feature point, such as the laser reflection apparatus in laser measurement. This article applied the optical measurement method to research detection of water chemical pollution. Use theoretical and mathematical models of optical measurement method to perform the detection of chemical contamination in water. Optical measurement method is the trend of future development.

Abstract: This article describes the elastic element of the servo valve, elaborates the definition of the stiffness of elastic element, analyzes the characteristics of existing rigidity measurement system, points out the limitations of the existing rigidity measurement system when it measures the large-stiffiness elastic element, utilizes a new measuring principle based on the existing stiffness test systems, uses the more accurate laser displacement measurement method to overcome the weaknesses of the existing stiffness test system, improves the measurement accuracy, makes stiffness measurements more accurate and promotes the stiffness measurement technology of the servo valve elastic element.

Abstract: In order to meet the measuring performance requirement of both high accuracy and large range when measuring the large-scale space angle formed by non-uniplanar lines quantitatively based on the engineering background of ammunition assembly angle test, we propose a measurement method that uses line structured laser as a common measurement reference and combined with vision inspection technique to achieve the measurement of large-scale space angle formed by non-uniplanar axes. Ammunition assembly angle have been measured accurately by using this method which provides a scientific approach for quality evaluation of that type of ammunition.

Abstract: The past rail wear measurement methods and equipments are summarized and the development process of portable inspection car for measuring rail wear is presented. The measurement system of this portable inspection car is developed based on the software platform of Labview. The car structure design is delicate and matched well with the image collecting device. This portable inspection car can measure the rail wear every 2.5 cm along the railway line and the measuring accuracy is 0.1mm.

Abstract: This paper presented a simple laser measuring method for measuring small displacement of a thin plastic string. The laser measuring method is based on the deviation of laser energy method. This measuring system consists of a laser diode and a photodetector. A photodetector received the laser beam from the laser diode is used to detect the laser energy deviation. A straight thin plastic string is placed between the laser diode and the photodetector to cover half area of the photodetector. When the string moves into or out the photodetector, the amount of the laser energy will change proportionally to the displacement of the string. A plastic string for the tennis is tested in this paper. The relation between the displacement of a plastic string and deviation of laser energy is verified by using a linear moving stage and a laser interferometer. The result showed the correlation is obtained. Thus, the displacement of a plastic string can be measured using the proposed laser measuring system.

Abstract: Conoprobe is used for non-contact measurement utilizing conoscopic holography technology, which has characteristics of high measurement precision and large measuring angle range. However, the conoprobe performs inaccurate and instable in gear measurement applications. To verify its accuracy, an experiment setup is built using high performance coordinate measuring machine (CMM) to measure surfaces of gaugeblocks that have similar material as gear workpieces. Compared the collected data from the CMM with the conoprobe values, those problems mentioned above are validated. In this study it can be stated that measuring accuracy of conoprobe drops dramatically when measuring bright metal surfaces, and even its measuring error could be more than dozens of microns when the measurement is in large angle, therefore it is completely not fit for precision measurement applications.