Position Detection Algorithm for Auto-Landing Containers by Laser-Sensor, Part I: 3-D Measurement

J. Ocean Eng. Technol. 2007;21(4):45-54.

Hong Keum-Shik,Lim Sung-Jin,Hong Kyung-Tae

School of Mechanical Engineering Pusan National University,School of Mechanical Engineering Pusan National University,Department of Mechanical and Intelligent Systems Engineering Pusan National University

컨테이너의 자동랜딩을 위한 레이저센서 기반의 절대위치 검출 알고리즘: 3차원 측정 (Part I)

홍금식,임성진,홍경태

부산대학교 기계공학부,부산대학교 기계공학부,부산대학교 지능기계공학과

Keywords: 3D position measurement, Transformation matrix, Laser sensor, Crane automation

핵심용어: 3차원 위치측정, 변환행렬, 레이저센서, 크레인 자동화

Abstract

In the context of auto-landing containers from a container ship to a truck or automatic guided vehicle and vice versa, this research investigates three schemes, one in Part I and two in Part II, for measuring the absolute position of a container. Coordinate transformations between the reference-coordinate, sensor-coordinate, and body-coordinate systems are briefly discussed. The scheme explored in Part I aims the use of three laser-slit sensors, which are relatively inexpensive. In this case, nine nonlinear equations are formulated for six unknown variables (three for orientation and three for position), so a closed-form solution is not available. Instead, an approximate solution through linearization was derived. An advantage of the method in Part I is its ability to measure an absolute position in 3D space, while a disadvantage is the computation time required to obtain pseudo-inverses and the approximate nature of the obtained solution. Numerical examples are provided.