• Title, Summary, Keyword: 레이저스캐닝

Search Result 152, Processing Time 0.045 seconds

A Study on a Laser Scanning Vibrometer Using a Magnetostrictive Resonant Device (자기 변형 공진 기구를 이용한 레이저 스캐닝 진동측정기에 관한 연구)

  • 이정화;류제길;박기환
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.15 no.11
    • /
    • pp.58-66
    • /
    • 1998
  • A low power consuming laser scanning vibrometer is studied for its development. For its optical system, a laser interferometer is constructed to use the Doppler effect. In order to reduce the driving power of the scanning system, a small displacement of the scanning system is produced, which is achieved by using a magnetostrictive actuator. A sufficient rotating angle of the scanning system is obtained by using an amplified displacement from the resonant phenomena of a second order mechanical system composed of a mass and spring. The control of the magnetostrictive actuator using a Terfenol-D is performed without using a feedback system to help reduce the power consumption. The vibration analysis is made for the sinusoidal scanning input to have the space domain information from the time domain of the velocity of a vibration object. As a partial work of development of a tow power consuming laser scanning vibrometer, in this work, a scanning system which has the above features is developed and experimentally investigated. For the purpose of the optical system calibration, the vibration measurement for one axis is presented and the future works are discussed.

  • PDF

Laser Scanning Technology for Ultrasonic Horn Location Compensation to Modify Nano-size Grain (나노계면 형성을 위한 초음파 진동자 위치보정을 위한 레이저 스캐닝 기술)

  • Kim, Kyugnhan;Lee, Jaehoon;Kim, Hyunse;Park, Jongkweon;Yoon, Kwangho
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.31 no.12
    • /
    • pp.1121-1126
    • /
    • 2014
  • To compensate location error of ultrasonic horn, the laser scanning system based on the galvanometer scanner is developed. It consists of the 3-Axis linear stage and the 2-Axis galvanometer scanner. To measure surface shape of three-dimensional free form surface, the dynamic focusing unit is adopted, which can maintain consistent focal plane. With combining the linear stage and the galvanometer scanner, the scanning area is enlarged. The scanning CAD system is developed by stage motion teaching and NURBS method. The laser scanning system is tested by marking experiment with the semi-cylindrical sample. Scanning accuracy is investigated by measured laser marked line width with various scanning speed.

Test-Bed Establishment Scheme for Terrestrial Laser Scanner' Performance Evaluation (지상레이저스캐너 성능평가를 위한 테스트베드 구축 방안)

  • Lee, In-Su;Tcha, Dek-Ki;Kim, Su-Jeong;Kim, Jin
    • Spatial Information Research
    • /
    • v.17 no.1
    • /
    • pp.39-49
    • /
    • 2009
  • 3D terrestrial laser scanners record high precision three-dimensional coordinates of numerous points on an object surface in a short period of time, and is applied to a wide variety of fields including geodesy, and civil engineering, archaeology and architecture, and emergency service and defence, etc. However, most of terrestrial laser scanner utilized in homeland, were imported from foreign country, and also was not authorized formally as the surveying instrument. Therefore, standard test facility to calibrate and perform its evaluation in order to utilize it in a variety of fields is required. This study deals with the test facility of foreign countries for terrestrial laser scanner and suggest the establishment scheme of domestic test facility.

  • PDF

Railway Track Extraction from Mobile Laser Scanning Data (모바일 레이저 스캐닝 데이터로부터 철도 선로 추출에 관한 연구)

  • Yoonseok, Jwa;Gunho, Sohn;Jong Un, Won;Wonchoon, Lee;Nakhyeon, Song
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.33 no.2
    • /
    • pp.111-122
    • /
    • 2015
  • This study purposed on introducing a new automated solution for detecting railway tracks and reconstructing track models from the mobile laser scanning data. The proposed solution completes following procedures; the study initiated with detecting a potential railway region, called Region Of Interest (ROI), and approximating the orientation of railway track trajectory with the raw data. At next, the knowledge-based detection of railway tracks was performed for localizing track candidates in the first strip. In here, a strip -referring the local track search region- is generated in the orthogonal direction to the orientation of track trajectory. Lastly, an initial track model generated over the candidate points, which were detected by GMM-EM (Gaussian Mixture Model-Expectation & Maximization) -based clustering strip- wisely grows to capture all track points of interest and thus converted into geometric track model in the tracking by detection framework. Therefore, the proposed railway track tracking process includes following key features; it is able to reduce the complexity in detecting track points by using a hypothetical track model. Also, it enhances the efficiency of track modeling process by simultaneously capturing track points and modeling tracks that resulted in the minimization of data processing time and cost. The proposed method was developed using the C++ program language and was evaluated by the LiDAR data, which was acquired from MMS over an urban railway track area with a complex railway scene as well.

Three-dimensional vibration measurement algorithm using one laser scanning vibrometer (한대의 LSV 를 이용한 3 차원 진동측정방법)

  • Kim, Dong-Kyu;Song, Ha-Jun;Park, Kyi-Hwan
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • /
    • pp.935-939
    • /
    • 2012
  • 3D vibration measurement is achieved using one laser scanning vibrometer(LSV) and Laser scanner(LS) by moving the LSV to three arbitrarily locations from the principle that vibration analysis based on the frequency domain is independent of the vibration signal based on time domain. The proposed system has the same effect as using three sets of LSVs. It has an advantage of reducing equipment costs. Analytical approach of obtaining in-plane and out-of-plane vibration of surface is introduced using geometrical relations between three LSV coordinates and vibration measured at three different locations.

  • PDF

Suggestion for Shape Measurement and Alloy Element Analysis of Korean Bells (한국종의 형상 및 합금성분 분석을 위한 제안)

  • Ko, Sun-Woo
    • The Journal of the Korea Contents Association
    • /
    • v.11 no.4
    • /
    • pp.428-439
    • /
    • 2011
  • It is well known that the sound characteristics of Korean bell depend on the shape and the alloy constituents. Development of the methods to acquire exact shape data and alloy constituents of the whole body of the bell is very important for the study and systematic management of Korean bells. The practical scanning and modeling methods to get shape data from optical triangulation laser scanners are proposed. The 3D shape data by the proposed methods can be the basis of diverse measurements such as curvature, volume, thickness and the distance between any two points. A nondestructive alloy constituents measuring method which can overcome the limitations of partial data collection and damages to Korean bells is also suggested to get the whole alloy characteristics. Following the developed methods, the data of the shapes and alloy constituents of 18 Korean bells are collected and the errors of existing measurement data for the shape have been corrected.