TITLE:
Position Determination of a Robot End-Effector Using a 6D-Measurement System Based on the Two-View Vision
AUTHORS:
Alexej Janz, Christian Pape, Eduard Reithmeier
KEYWORDS:
Hydraulic Analysis; Differential Evolution; Optimization Model
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.3 No.7,
November
5,
2013
ABSTRACT: A mechatronic system based on the micro-macro-kinematic consists of
an industrial robot and a piezoelectric stage mounted on the robot’s end-effector
and has to carry out operations like micro-assembly or micro-milling. The piezoelectric
stage has to compensate the positioning error of the robot. Therefore, the
position of the robot’s end-effector has to be measured with high accuracy.
This paper presents a high accuracy 6D-measurement system, which is used to determine
the position and orientation of the robot’s end-effector. We start with the
description of the operational concept and components of the measurement
system. Then we look at image processing methods, camera calibration and reconstruction
methods and choose the most accurate ones. We apply the well-known pin-hole
camera model to calibrate single cameras. Then we apply the epipolar geometry
to describe the relationship between two cameras and calibrate them as a stereo
vision system. A distortion model is also applied to enhance the accuracy of
the system. The measurement results are presented in the end of the paper.