The concept of a active laser safety device based on the position control of the focus is implemented as a part of this research project in close consultation with the Employer’s Liability Insurance Association and industrial partners.
Laser systems for material processing are increased used for industrial mass production due to their excellent properties such as high process velocity and precise energ input. The technological progress in laser manufacturing process is defined by steadily higher laser output power as well as improved beam quality. This further development enables the transmission of high radiation intensities over several meter-reaching distances in free jet with a focal spot diameter of a few ten to at least hundret micrometer. An increase of the risk potential can be observed because of the facts, that a laser beam hazards persons and machines in a wide environment and that the distance between laser optics and work piece is great enough to get into the course of the beam. The power densities are such high, that several studies show that the apply of passive safety barriers is obsolete.
The aim of this research project is the realization of an innovative laser safety potential, that offers an econimical benefit and a safe handling besides a higher safety.
The literatre research and the classification of common laser systems follow a poll with representatives of the Employer’s Liability Insurance Association and the industrial partners. The requirements for the safety system are defined based on this and tests for the system’s inspection are specified. By means of this specification the concept for safety installations is made with the agreement oft he Employer’s Liability Insurance Association and the industrial partners. An external organization executes the hard- and software development with the iwb’s technical support corresponding to this elaboration. The result is to be a pattern system that corresponds to the functional principle of the in the pretests used item with the differenz that the components are in accordance with the safety standards. The monitoring of the focus ensures the principle of epipolaric geometry. Based on two cameras’ pictures – the cameras are set on the focal ray from different perspectives – a stereo construction is done. The monitoring of the manipulator’s position is depicted in analogous functionality. Those two position informations – position focus and position manipulator – are compared to predestimated, permitted coordinates for the workspace. If the light spot is not in the predefined, permitted area, the laser system is turned off as soon as possible by the emergency stop equipment. A passive safety barrier has to bridge over the latency period untill the laser system’s laying. The created prototype is implemented in a remote laser system at the iwb, tested and improvments are included if needed. Due to the collected experiences about this safety system, design- and testinstructions are defined for the implementation of this kind of safety installations. That is the purpose to transfer the gained insights to other laser systems.
A functional model of the central active laser safety installations is build at this time.
This research project is supported by funds of the Employer’s Liability Insurance Association. The DGUV is thanked for this. The responsibility for the content of this publication lies with the author.