Laser projection boosts production of composites
When positioning and laying out large, flat materials during the production of composites, many companies still work with templates or measure manually. Both are enormously tedious and susceptible to mistakes. Laser projectors replace the time-consuming process by projection even complex contours with millimetre precision.
The manual alignment with the clumsy templates and the wearisome measuring are now a thing of the past. Furthermore, the laser projection optimises the work processes and improves the quality thanks to the immediate visual inspection. The templates still widely used for aligning large, flat materials and for producing composites today only meet the high demands in industry to a limited extent. The often complex forms with high demands on dimensional tolerances and quality require an enormous amount of manual labour for measuring and handling. Furthermore, the production of the templates is laborious and costly, because a new template has to be manufactured for every new shape. In addition, templates wear quickly and tie up a great deal of warehousing capacity due to their size and form. This is unprofitable and time-consuming, particularly in the development and prototype phase when modifications frequently have to be made. The production of large, flat parts using templates is therefore expensive and lacks flexibility.
Incorrectly laid mats during the production of composites, such as fibre-reinforced parts, always results in scrap as the expensive material cannot be re-used after stoving.
Companies have to react to the growing demands on quality and on efficient and flexible production with improved production methods. Companies who still work with templates do not utilise the advantages that advanced tools such as laser projectors offer.
The laser projectors from LAP for example replace the clumsy templates by projecting complex contours onto the working surface with millimetre precision. In order to image the contour on the surface, two rotating software-controlled mirrors deflect the laser beam. The laser dot moves at very high speed along the working surface, creating the impression of a continuous line. The system draws the necessary information from the CAD data.
A projection system essentially comprises one or more projectors and a computer with the projection software. The software can be operated independently or integrated into the machine controller via an interface. In most cases, the laser projectors are mounted perpendicularly above the working surface on a supporting structure or fastened to the ceiling. Thanks to the compact form, the low weight and integrated swivel mount, the low-maintenance projectors can be employed practically anywhere.
Calibration is necessary for the precise 1:1 projection. It establishes the exact relationship between the projector position and the projection surface. For this the system scans the “targets”. These are reflectors located at previously surveyed points. From this the system calculates the position of the projector relative to the projection surface. A manual basic calibration is required just once immediately after installation. During day-to-day operation, the system checks the calibration automatically within seconds. That rules out operator errors and ensure lasting maximum precision and reproducibility.
Mulit-coloured system
During the development of the LAP laser projectors, the engineers attached great importance to ease of operation. Replacement of the projector, for example during maintenance or for a hardware upgrade, involves loosening just one screw. No specialist personnel are required. The new or upgraded device supplied by LAP continues to fit exactly into the existing mounting, is quickly installed and calibrates itself automatically. The whole process typically takes just a few minutes.
LAP says they are the only manufacturer of laser projectors that can image three colours simultaneously. That allows certain areas where particular attention is necessary to be highlighted. With the change in colour from red to yellow or green, the system can also signal which parts the worker still has to position, which parts are in process or are already finished. It is also helpful, however, to select the colour with which the contour can best be seen on the base material.
The second colour (such as red) can be used in the prefabricated building industry, for example, to mark the outlines of plug socket or window openings and to show after positioning of the shuttering elements whether they are in the right place. The third colour can display, for example, a part number.
The LAP PRO-SOFT software offers a number or work-simplifying features: Taking over of CAD data, transmission of the control signals to the projector, digitisation of parts, automatic calibration and naturally visualisation of the contours. The LAP software can even manage and control whole working processes. “This special feature provides enormous relief for the operator, particularly with complex work processes such as the production of composites. Furthermore, it is a convenient and reliable quality assurance tool,” explains Axel Rieckmann, Sales Director Industry at LAP.
“The special COMPOSITE PRO systems project the exact position of the various mats or parts and an unambiguous identification number. The system guides the worker step-by-step through the production of the composites and forgets none of the parts. In addition, the individual work steps are documented.”
Aircraft manufacturer Airbus, for example, optimises the efficiency of the production of carbon fibre-reinforced parts for the wings, fuselage and tail of the new Airbus A350 XWB with the laser projectors. Here the aircraft manufacturer uses carbon fibre-reinforced materials also for components of the fuselage and for the complete wings.
That significantly reduces the weight, and hence the fuel consumption, of the more than 65 metre long aircraft with its wing span of over 60 metres. LAP Sales Director Industry, Axel Rieckmann: “The aircraft manufacturer Airbus has placed orders with LAP for the supply of a total of 220 laser projection systems. LAP is thus a strategic partner of Airbus, and that’s something we’re proud of.”
When building up the carbon fibre parts, the laser beams project the position of the individual carbon fibre mats. That saves time and money, as the alignment of the parts using the clumsy templates and the time-consuming measuring are eliminated.
Errors can be practically ruled out
In addition, the correct position and alignment of the carbon fibre mats can also be checked. After laying up, the second colour indicates whether the mat is correctly positioned. Errors in production can thus be practically ruled out. During production, the projectors guide the workers step-by-step through the whole make-up of the components. As in an electronic ply book, the individual work steps such as the positioning of the carbon fibre mats or the exact marking of rib structures, honeycombs and other integral elements are displayed in the correct sequence. All the elements are thus in the right place at the right time, checked and documented.
The multi-head system is suitable for the handling of large parts. Several projectors with overlapping working ranges cover the whole length. There are thus practically no limits to the size of the working area. The multi-tasking feature of PRO SOFT makes it possible to display the contour they are currently working on separately for different working groups. All the teams can therefore work completely independently of one another.
The advantages of the new technology at a glance
- Particularly simple: Laser calibration, outlines projected, element posi tioned – quick and uncomplicated
- Bye-bye templates: The costly pro duction, storage, management and cumbersome handling are all a thing of the past
- Very high precision
- Multitasking for optimisation: Sever- al teams can work simultaneously on the same component
German Summary
Beim Ausrichten und Verlegen flächiger Materialien und beim Herstellen von Verbundwerkstoffen arbeiten viele Unternehmen immer noch mit Schablonen oder messen manuell. Beides ist enorm aufwändig und fehleranfällig. Laserprojektoren ersetzen das zeitraubende Verfahren, indem sie selbst komplexe Konturen millimetergenau projizieren. Das manuelle Ausrichten mit den unhandlichen Schablonen und das umständliche Einmessen entfallen. Zusätzlich optimiert die Laserprojektion die Arbeitsabläufe und verbessert die Qualität durch sofortige optische Kontrolle. Der deutschsprachige Beitrag ist nachzulesen auf: www.aerotec-online.com/aero0211lap
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