• 한국ITS학회:학술대회논문집
• /
• 2008.11a
• /
• pp.531-536
• /
• 2008

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.9 no.5
• /
• pp.70-75
• /
• 2010

In this paper, laser marking systems dedicated to cylinderical parts was developed. We first develop the marking device which consists of Nd-Yag laser, galvano scanner and additional rotational axis, then develop algorithm for supporting the digital image with bmp data format. Additional rotational axis is so attached as to rotate the cylinderical parts for marking its whole surface. The image is separated into line by line and the separated line image is sent to galvano scanner while rotating the additional axis simultaneously. CxImage library, famous open source code, is employed for the image processing. The developed method was tested with various images and shows that it reduces marking time significantly without reducing marking quality.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2009.10a
• /
• pp.25-26
• /
• 2009

• Journal of Institute of Control, Robotics and Systems
• /
• v.22 no.10
• /
• pp.811-816
• /
• 2016

In light of recently developed 3D printers for rapid prototyping, there is increasing attention on the 3D scanner as a 3D data acquisition system for an existing object. This paper presents a prototypical 3D scanner based on a striped laser light image. In order to solve the problem of shadowy areas, the proposed 3D scanner has two cameras with one laser light source. By using a horizontal rotation table and a rotational arm rotating about the latitudinal axis, the scanner is able to scan in all directions. To remove an additional optical filter for laser light pixel extraction of an image, we have adopted a differential image method with laser light modulation. Experimental results show that the scanner's 3D data acquisition performance exhibited less than 0.2 mm of measurement error. Therefore, this scanner has proven that it is possible to reconstruct an object's 3D surface from point cloud data using a 3D scanner, enabling reproduction of the object using a commercially available 3D printer.

• Proceedings of the KSME Conference
• /
• 2008.11a
• /
• pp.1778-1783
• /
• 2008

A compact and two-dimensional atomic force microscope (AFM) using an orthogonal sample scanner, a calibrated homodyne laser interferometer and a commercial AFM head was developed for use in the nanometrology field. The x and y position of the sample with respect to the tip are acquired by using the laser interferometer in the open-loop state, when each z data point of the AFM head is taken. The sample scanner which has a motion amplifying mechanism was designed to move a sample up to $100{\times}100{\mu}m^2$ in orthogonal way, which means less crosstalk between axes. Moreover, the rotational errors between axes are measured to ensure the accuracy of the calibrated AFM within the full scanning range. The conventional homodyne laser interferometer was used to measure the x and y displacements of the sample and compensated via an X-ray interferometer to reduce the nonlinearity of the optical interferometer. The repeatability of the calibrated AFM was measured to sub-nm within a few hundred nm scanning range.

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

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.12 s.255
• /
• pp.1611-1617
• /
• 2006

A compact and two-dimensional atomic force microscope (AFM) using an orthogonal sample scanner, a calibrated homodyne laser interferometer and a commercial AFM head was developed for use in the nano-metrology field. The x and y position of the sample with respect to the tip are acquired by using the laser interferometer in the open-loop state, when each z data point of the AFM head is taken. The sample scanner which has a motion amplifying mechanism was designed to move a sample up to $100{\times}100{\mu}m^2$ in orthogonal way, which means less crosstalk between axes. Moreover, the rotational errors between axes are measured to ensure the accuracy of the calibrated AFM within the full scanning range. The conventional homodyne laser interferometer was used to measure the x and y displacements of the sample and compensated via an X-ray interferometer to reduce the nonlinearity of the optical interferometer. The repeatability of the calibrated AFM was measured to sub-nm within a few hundred nm scanning range.

• International Journal of Highway Engineering
• /
• v.12 no.4
• /
• pp.71-78
• /
• 2010

The road safety depend on many road factors like vertical alignment, horizontal alignment and road cross section angle. These data are hardly to get with drawings, and the real data are differ from drawings because of road pavement overlay, etc. To get these data, so many time and cost are needed, moreover it is dangerous work in heavy traffic road. In this study we obtained the road safety data with RoSSAV(Road Safety Survey & Analysis Vehicle) of Korea Institute of Construction Technology in accordance with traffic flow, and make analysis of road safety with the vertical alignment, horizontal alignment and road cross section angle data. We derived the safety improvement method in Young-dong accident prone spot and described detail method in this paper.

• Korean Journal of Optics and Photonics
• /
• v.27 no.5
• /
• pp.165-173
• /
• 2016

In this paper, we propose a three-dimensional (3D) scanning system based on two line lasers. This system uses two line lasers with different wavelengths as light sources. 532-nm and 630-nm line lasers can compensate for missing scan data generated by geometrical occlusion. It also can classify two laser planes by using the red and green channels. For automatic registration of scanning data, we control a stepping motor and divide the motor's rotational degree of freedom into micro-steps. To this end, we design a control printed circuit board for the laser and stepping motor, and use an image processing board. To compute a 3D point cloud, we obtain 200 and 400 images with laser lines and segment lines on the images at different degrees of rotation. The segmented lines are thinned for one-to-one matching of an image pixel with a 3D point.

• The korean journal of orthodontics
• /
• v.37 no.6
• /
• pp.407-420
• /
• 2007

The aim of this study was to compare the differences in closing extraction spaces between maxillary first premolar and second premolar extractions using 3-dimensional finite element analysis (FEA). Methods: Maxillary artificial teeth were selected according to Wheeler's dental anatomy. The size and shape of each tooth, bracket and archwire were made from captured real images by a 3D laser scanner and FEA was performed with a 10-noded tetrahedron. A $10^{\circ}$ gable bend was placed behind the bull loop on a $0.017"{\times}0.025"$ archwire. The extraction space was then closed through 12 repeated activating processes for each 2mm of space. Results and Conclusions: The study demonstrated that the retraction of anterior teeth was less for the second premolar extraction than for the first premolar extraction. The anterior teeth showed a controlled tipping movement with slight extrusion, and the posterior teeth showed a mesial-in rotational movement. For the second premolar extraction, buccal movement of posterior teeth was highly increased.