Product Code: ICAL07_410

Control Method for 3D Laser Forming Based on Geometrical Data
Authors:
Emile Abed, The University of Liverpool; Liverpool Great Britain
Stuart Edwardson, The University of Liverpool; Liverpool Great Britain
Konrad Bartkowiak, Fraunhofer Usa; Plymouth MI USA
Geoff Dearden, The University of Liverpool; Liverpool Great Britain
Ken G Watkins, The University of Liverpool; Liverpool Great Britain
Presented at ICALEO 2007

2-Dimensional laser forming can currently control bend angle, with reasonably accurate results, in various materials including aerospace alloys. However, this is a different situation for 3-Dimensional laser forming. To advance this process further for realistic forming applications and for straightening and aligning operations in a manufacturing industry it is necessary to consider larger scale controlled 3D laser forming. The work presented in this paper uses a predictive and adaptive approach to control the laser forming of Mild Steel and Aluminium sheet into a desired surface. Key to the control of the process was the development of a predictive model, detailed in the paper, to give scan strategies based on a required geometry and the surface error. The forming rate and distribution of the magnitude of forming across the surface were controlled in the closed loop by the process speed. When the geometry is not formed within one pass, an incremental adaptive approach is used for subsequent passes, utilising the error between the current and desired geometry to give a new scan strategy, thus any unwanted distortion due to material variability can be accounted for and distortion control and removal is possible.