Diagnosis and modelling of nonlinear dynamics in laser cutting, welding and drilling

Laser cutting and welding are well established industrial applications. To maintain productivity and to guarantee product quality the industry tries to introduce monitoring and control systems. The long term goal is the autonomous laser machine. Signal assessment is advancing by monitoring and simulation of the dynamical processes. Applying the advanced results about diagnosis and modelling broadens the potentials to cope with productivity and quality features in drilling, trepanning and fine cutting. As result, in cutting two mechanisms for the formation of adherent dross are revealed theoretically, identified by the monitoring system and can be avoided by modulation of the laser beam power. In welding, the dynamic model predicts the formation of pores sets in or is suspended depending on modulation frequency for the laser power. In drilling the mechanisms governing the maximum depth of the drilled hole - still showing efficient melt removal - are identified experimentally and can be related to the processing parameters theoretically.