• Journal of the Korean Society for Precision Engineering
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• v.17 no.10
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• pp.119-124
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• 2000

One of the main problems in 3D shape measuring systems that use the triangulation of line-shaped laser light is precise center line detection of line-shaped laser stripe. The intensity of a line-shaped laser light stripe on the CCD image varies following to the reflection angles, colors and shapes of objects. In this paper, a new center line detection algorithm to compensate the local intensity variation on a line-shaped laser light stripe is proposed. The 3-D surface shape measuring system using the proposed center line detection algorithm can measure 3-D surface shape with enhanced measurement resolution by using the dynamic shape reconstruction with adaptive pattern clustering of the line-shaped laser light. This proposed 3-D shape measuring system can be easily applied to practical situations of measuring 3-D surface by virtue of high speed measurement and compact hardware compositions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1824-1827
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• 2003

The sheet metal shearing process is normally used in the precision elements such as semi-conductor components. In precision elements, burrs usually reduce the quality of machined parts and cause interference, jamming and misalignment during assembly procedures and because of their sharpness, they can be safety hazard to personnel. Furthermore, not only burrs are hard to predict and avoid, but also deburring, the process of removing burrs, is time-consuming and costly. In order to get the burr-free parts, therefore, we developed the precise burr measuring system using the laser. The laser burr measuring system consists of the laser probe, the photo detector, the achromatic doublet lens, and the rotary ＆ the X-Y table. In previous reports, we used simple vertical measuring method. But, as we used relatively bigger laser spot diameter and had the limited reflection angle, it was difficult to obtain the precise measuring results. So called, the spot size effect makes the profile of burr measured distorted and the burr height measured smaller. By introducing the novel laser measuring method which employing the achromatic lens system and the tilting mechanism, we could make the spot size smaller and get the appropriate beam direction angle. Through the experiments, the accuracy of the developed system is proved. The burr height measured during the punching process can be used for automatic deburring and in-situ aligning.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.7
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• pp.9-14
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• 2011

A spectroscopic measuring system was developed in order to determine optical gain of gas laser discharge for any optical transitions between 190[nm] and 800[nm] without laser resonator. With an image optical system and a feedback optical system emission light of laser discharge are entered in a monochromator and received at a photomultiplier. Subsequently optical gain and line intensity are measured.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.690-695
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• 2004

A new dimension measuring method for the measurement of diameter of an object has been developed using laser triangulation. The 3-D data of an object was calculated from the 2dimensional image information obtained by the laser stripe using the laser triangulation. The system can measure the diameter of hole not only in a normal plane but also in an incline plane. We can experiment with magnification that is optimized according to size of object using zoom lens. In this paper, the theoretical formula and calibration of the system were described. The measuring precision of the system was investigated by experiment.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.6
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• pp.240-245
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• 2002

In this paper, a novel optical measuring system for the measurement of nonuniform electric field was proposed. The electric field distorted by the discharges was detected through proposed optical measuring system based on the Pockets effect and Mach-Zehnder interferometer. In order to produce distorted electric field, corona discharge was generated from needle-plane electrode in air and detected by optical measuring system. This optical measuring system is constructed by He-Ne laser, single mode optical fiber, $2{\times}2$ 50/50 beam splitter, $LiNbO_3$ Pockets cell, photo detector and PC. In this system, output signal of Pockels sensor is measured by digital oscilloscope and transferred to the PC for recording and statistical processing. Through this paper, a promising possibilities of proto-type optical measuring system were evinced.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.4
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• pp.427-433
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• 2010

With recent increased demand for reverse engineering in dental machining, the 3D laser scanner is widely used for inspection of artificial pontic. In order to overcome the optical drawback of laser scanner, such as irregular scatter, direction of beam, and the influence of surface integrity, it is developed in this study a new 3D measuring system for artificial pontic using spherical coordinate system mechanism by point laser sensor, which keeps the direction of beam normal to surface consistently. The comprehensive integrated system is established to evaluate the improvement of accuracy with data acquisition system. The experimental results for measuring a master ball and pontic models shows the excellent form accuracy and repeatability compared with conventional apparatus. Also, these results shows the possibility to apply this system for the measuring purpose within 0.05mm accuracy of pontic at the sharp edge or margin contour, which was difficult to measure at the conventional systems.

• Journal of Navigation and Port Research
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• v.28 no.4
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• pp.323-331
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• 2004

This paper introduces a novel approach that can provide the three dimensional information about the movement of a spreader by using two CCD cameras and a laser distance measuring unit in order to derive ALS (Automatic Landing System) in the crane used at a harbor. So far a kind of 2D Laser scanner sensor or laser distance measuring units are used as comer detectors for the geometrical matching between the spreader and a container. Such systems provide only two dimensional information which is not enough for an accurate and fast ALS. In addition to this deficiency in performance, the price of the system is too high to adapt to the ALS. Therefore, to overcome these defects, we proposed a novel method to acquire the three dimensional spreader information using two CCD cameras and a laser distance measuring unit. To show the efficiency of proposed method, real experiments are performed to show the improvement of accuracy in distance measurement by fusing the sensory information of the CCD cameras and a laser distance measuring unit.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.201-206
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• 2004

Laser scanner are getting used for inspection and reverse engineering in industry such as motors, electronic products, dies and molds. However, due to the lack of efficient scanning technique, the tasks become limited to the low accuracy purpose. The main reasons for this limitation for usefulness are caused from the optical drawback, such as irregular reflection, scanning direction normal to measuring surface, the influence of surface integrity, and other optical disturbances. To overcome these drawback of laser scanner, this study propose the mechanism to reduce the optical trouble by using the 2 kinds of rotational movement axis and by composing the spherical coordinate to scanning the surface keeping normal direction consistently. So, it could be designed and interfaced the measuring device to realize that mechanism, and then it could acquisite the accurate 3D form cloud data. Also, these data are compared with the standard master ball and the data acquisited from the touch point sensor, to evaluate the accuracy and stability of measurement and to demonstrate the implementation of an dental tooth purpose system

• Journal of Korean Association for Spatial Structures
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• v.21 no.3
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• pp.25-34
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• 2021

This study develops a new device system for measuring a slope of object with non-adhesive, non-contact and non-face-to-face, namely Inclinometer Slope Laser Measuring (ISLM), that is applicable in the field. This system includes cradle, laser, camera, and computer and the filming and is performed after laser projection at programmed intervals. After measuring the amount of displacement converted to numerical values, these values can then be transferred to the office using the selected data transmission method. The obtained results from the test carried out to verify the reliability of the ISLM system indicated that the ISLM system can measure with accurately level of 0.1mm/Pixel at 1m distance and when increasing the camera resolution, the precision might increase proportionally. Therefore, the proposed measure system may widely apply on-site for various constructions, especially, in the case of object with very high surface temperature where exhibits difficulty to directly measure the adjacent structures. However, due to the sensitive reaction to the illuminance, this method can be applied with caution at times of large changes in illuminance, such as at dawn and at dusk.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.10
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• pp.1730-1741
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• 1997

In this paper, we developed a surface profile measuring system and a profile measuring software for EGL conductor roll. For the profilemeter, we designed a linear guided control system with Laser displacement sensors and developed a 3-dimensional software. Additionally, the AC motor and AC motor driver were used to control the precise position of linear guide system. The measuring principle of the Laser sensor is optical triangulation method. Also, two Laser sensors were used to remove the disturbance and vibration effects of the linear guide system.