Height control of laser metal-wire deposition based on iterative learning control and 3D scanning
Journal article, 2012

Laser Metal-wire Deposition is an additive manufacturing technique for solid freeform fabrication of fully dense metal structures. The technique is based on robotized laser welding and wire filler material, and the structures are built up layer by layer. The deposition process is, however, sensitive to disturbances and thus requires continuous monitoring and adjustments. In this work a 3D scanning system is developed and integrated with the robot control system for automatic in-process control of the deposition. The goal is to ensure stable deposition, by means of choosing a correct offset of the robot in the vertical direction, and obtaining a flat surface, for each deposited layer. The deviations in the layer height are compensated by controlling the wire feed rate on next deposition layer, based on the 3D scanned data, by means of iterative learning control. The system is tested through deposition of bosses, which is expected to be a typical application for this technique in the manufacture of jet engine components. The results show that iterative learning control including 3D scanning is a suitable method for automatic deposition of such structures. This paper presents the equipment, the control strategy and demonstrates the proposed approach with practical experiments.




Additive layer manufacturing

powder deposition


power diode-laser

Laser metal deposition


Metal wire

Iterative learning control

3D scanning





A. Heralic

Volvo Group

University West

A. K. Christiansson

University West

Bengt Lennartson

Chalmers, Signals and Systems, Systems and control, Automation

Optics and Lasers in Engineering

0143-8166 (ISSN)

Vol. 50 9 1230-1241

Areas of Advance


Subject Categories

Electrical Engineering, Electronic Engineering, Information Engineering



More information

Latest update