CLAW: Clean and low distortion accurate welding for micro assembly

• Research unit: EU RFP
• Project number: 97.0507-1

Key words (English)

Laser welding; clean welding; micro assembly; grippers

Alternative project number (English)

EU project number: BRPR-CT98-0643

Research programs (English)

EU-programme: 4. Frame Research Programme - 2.1 Industrial and materials technologies

Short description (English)

See abstract

Partners and International Organizations (English)

SIEMENS (D), ILT (D), CLFA (F), PHILIPS (NL), MACGREGOR (UK), HASS LASER (D), ETA (CH), CHEVAL FRERES (F), LOIUGHBOROUGH UNIVERSITY (UK), RWP (D), EU-JRC-IAM (NL)

Abstract (English)

Industrial companies manufacturing miniaturised electrical, mechanical and optical systems suffer from the many restrictions of today's major micro-assembly techniques. These restrictions are primarily related to handling, contamination and distortion of the micro parts during the assembly process.
The subject of CLAW is to bring important improvements to eliminate some of the abovementioned restrictions. Three main industrial issues were pursued in the project:
1. Prevent product contamination during micro-welding, such that subsequent cleaning is not necessary. This is achieved when the contamination levels are sufficiently low and the particle sizes are in the sub-micron or nano-meter range.
2. Provide tools and set-ups to handle and manipulate micro-parts with sub-micron accuracy in an industrial production line. This is mainly achieved with CSEM's ice-gripper that allows delicate parts to be gripped and positioned with sub-micron accuracy within a cycle time of 2 seconds, without leaving a permanent deformation of the parts.
3. Use laser micro-welding or micro-arc welding processes with sub-micron final accuracy to join micro-parts. A novel, industrial scale micro-welding process is available with low distortions in the range of 0.5 I.J m and 1 mrad in angle, respectively and when a total assembly time of 2 seconds is realized (including handling and manipulation).
Within the scope of this project the complete process chain will be investigated consisting of novel micro-part gripping and handling tools, the novel micro-welding processes, and computer support for part-design and process control.
CSEM has designed and manufactured an appropriate ice gripper that allows the handling of odd parts of different size, shape and materials during their assembly and laser welding. The new gripper is equipped with a Microcontroller unit that interfaces with the robot electronics and manage the closed- loop control of the temperature at the tip of the gripper. The gripper and its electronics were mounted and tested on a new assembly machine developed by SMH Automation.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 97.0507-1