Phase-sensitive vision technique for high accuracy position measurement of moving targets

Autonomous posture detection and self-localization of roadheaders is the key to automatic tunneling and roadheader robotization. In this paper, a multi-sensor based positioning method, involving an inertial system for altitude angles measurement, total station for coordinate measurement, and sensors for measuring the real-time length of the hydraulic cylinder is presented for roadheader position measurement and posture detection. Based on this method, a positioning model for roadheader and cutter positioning is developed. Additionally, flexible trajectory planning methods are provided for automatic cutting. Based on the positioning model and the trajectory planning methods, an automatic cutting procedure is proposed and applied in practical tunneling. The experimental results verify the high accuracy and efficiency of both the positioning method and the model. Furthermore, it is indicated that arbitrary shapes can be generated automatically and precisely according to the planned trajectory, employing the automatic cutting procedure. Therefore, unmanned tunneling can be realized by employing the proposed automatic cutting process.

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High-accuracy longitudinal position measurement using self-accelerating light

Applied Optics ◽

10.1364/ao.420590 ◽

2021 ◽

Vol 60 (11) ◽

pp. 3203

Author(s):

Shashi Prabhakar ◽

Stephen Z. D. Plachta ◽

Marco Ornigotti ◽

Robert Fickler

Keyword(s):

High Accuracy ◽

Position Measurement ◽

Longitudinal Position

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High-accuracy position and orientation measurement of extended two-dimensional surfaces by a phase-sensitive vision method

Applied Optics ◽

10.1364/ao.41.005503 ◽

2002 ◽

Vol 41 (26) ◽

pp. 5503 ◽

Cited By ~ 22

Author(s):

Patrick Sandoz ◽

Vincent Bonnans ◽

Tijani Gharbi

Keyword(s):

High Accuracy ◽

Two Dimensional ◽

Orientation Measurement ◽

Phase Sensitive ◽

Position And Orientation ◽

Position And Orientation Measurement

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The Development of Initial Position End-of-Line Test System for PMSM

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1061-1062.995 ◽

2014 ◽

Vol 1061-1062 ◽

pp. 995-998

Author(s):

Yan Ling Cao ◽

Ping Cao

Keyword(s):

Full Range ◽

High Accuracy ◽

Test System ◽

Initial Position ◽

Position Measurement ◽

Zero Crossing ◽

The North ◽

Line Test ◽

And Performance ◽

Crossing Point

The resolver is widely used in the production applications due to the robust mounting and high accuracy at full range. However, the mounting accuracy of such sensors will significantly limit the torque accuracy and performance if the initial positions are not calibrated at the end-of-line (EOL) test. An initial position EOL test system is designed base on the production requirements. A simple initial position measurement method is introduced and applied to the PMSM motor, which measures the back EMF and the North mark (NM) signal of the resolver. The time difference between the back EMF zero crossing point and NM signal is divided by the back EMF period and then the initial position is calculated. The method is validated on the target bench and experiments prove the EOL test system is suit for the mass production.

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A hand–eye calibration algorithm based on screw motions

Robotica ◽

10.1017/s0263574708004608 ◽

2009 ◽

Vol 27 (2) ◽

pp. 217-223 ◽

Cited By ~ 15

Author(s):

Zijian Zhao ◽

Yuncai Liu

Keyword(s):

Computer Vision ◽

Linear Equations ◽

High Accuracy ◽

Robotic Hand ◽

Important Research ◽

Research Task ◽

Screw Motions ◽

Calibration Algorithm ◽

Vision Technique ◽

Computer Vision Technique

SUMMARYWhen computer vision technique is used in robotics, robotic hand–eye calibration is a very important research task. Many algorithms have been proposed for hand–eye calibration. Based on these algorithms, we introduce a new hand–eye calibration algorithm in this paper, which employs the screw motion theory to establish a hand–eye matrix equation by using quaternion and gets a simultaneous result for rotation and translation by solving linear equations. The algorithm proposed in this paper has high accuracy and stable computational efficiency and can be understood easily. Both simulations and real experiments show the superiority of our algorithm over the comparative algorithms.

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High Accuracy Slit-Ray Position Measurement

Journal of Engineering for Industry ◽

10.1115/1.3187849 ◽

1988 ◽

Vol 110 (1) ◽

pp. 92-94 ◽

Cited By ~ 3

Author(s):

Y. Nomura ◽

H. Naruse ◽

T. Morimitsu

Keyword(s):

Regression Analysis ◽

Error Analysis ◽

Image Plane ◽

High Accuracy ◽

Shape Measurement ◽

Position Measurement

The accuracy of slit-ray position measurement on an image plane of a TV camera is improved to the order of one-hundredth of pixel spacing by a regression analysis and an error analysis. Also, the effectiveness of the method is confirmed by means of shape measurement experiments.

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