Share Email Print

Proceedings Paper

Parallel robot for micro-assembly with integrated innovative optical 3D sensor
Author(s): Juergen Hesselbach; Diana Ispas; Gero Pokar; Sven Soetebier; Rainer Tutsch
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Recent advances in the fields of MEMS and MOEMS often require precise assembly of very small parts with an accuracy of a few microns. In order to meet this demand, a new approach using a robot based on parallel mechanisms in combination with a novel 3D-vision system has been chosen. The planar parallel robot structure with 2 DOF provides a high resolution in the XY-plane. It carries two additional serial axes for linear and rotational movement in/about z direction. In order to achieve high precision as well as good dynamic capabilities, the drive concept for the parallel (main) axes incorporates air bearings in combination with a linear electric servo motors. High accuracy position feedback is provided by optical encoders with a resolution of 0.1 μm. To allow for visualization and visual control of assembly processes, a camera module fits into the hollow tool head. It consists of a miniature CCD camera and a light source. In addition a modular gripper support is integrated into the tool head. To increase the accuracy a control loop based on an optoelectronic sensor will be implemented. As a result of an in-depth analysis of different approaches a photogrammetric system using one single camera and special beam-splitting optics was chosen. A pattern of elliptical marks is applied to the surfaces of workpiece and gripper. Using a model-based recognition algorithm the image processing software identifies the gripper and the workpiece and determines their relative position. A deviation vector is calculated and fed into the robot control to guide the gripper.

Paper Details

Date Published: 18 October 2002
PDF: 12 pages
Proc. SPIE 4902, Optomechatronic Systems III, (18 October 2002); doi: 10.1117/12.467484
Show Author Affiliations
Juergen Hesselbach, Technische Univ. Braunschweig (Germany)
Diana Ispas, Technische Univ. Braunschweig (Germany)
Gero Pokar, Technische Univ. Braunschweig (Germany)
Sven Soetebier, Technische Univ. Braunschweig (Germany)
Rainer Tutsch, Technische Univ. Braunschweig (Germany)

Published in SPIE Proceedings Vol. 4902:
Optomechatronic Systems III
Toru Yoshizawa, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?