Flexible and Reconfigurable Laser Processing Tool (FlexLase)

Laser processing of metals and alloys is extensively used in modern manufacturing for various applications including
drilling, cutting, welding, surface modification, etc. Industrial robots are currently used for some laser processing
applications like cutting and welding where the allowable tolerance limit is around 100 micron. However, applications like
laser drilling requires a positional accuracy around 20-25 microns which is not feasible with existing robotic systems and
hence is mostly performed using expensive CNC based systems. This project aims to develop a flexible robotic laser
processing system which can have a position accuracy of less than 20 micron, and that can be used for most laser
applications including laser drilling.
By exploiting the speed and precision of modern CCD cameras, the positional error of the robot will be calculated based on
the coordinates (of the laser interaction point and a reference point) obtained from the CCD camera. The CCD camera will
be co-axial to the nozzle exit. The positional error calculated by the vision system will be compensated by offsetting the
laser beam and nozzle position, through a novel mirror and optical assembly.
The project will initially undertake proof-of-principle experiments to establish the positional error from the CCD camera
image. A new algorithm will be developed to extract the real-time positional error from the CCD camera image and to
facilitate compensation of the error by offsetting the laser beam position. National Instruments (NI) real-time module along
with a NI CompactRIO system will be used to achieve the required cycle time (less than 10ms). Finally, the CCD camera
and the software will be integrated with the robot and the nozzle assembly, to achieve a truly flexible manufacturing
system.
The immediate application will be on robotic laser drilling of aerospace combustion chambers. It is expected that the
FlexLase system will be more accurate and affordable than the systems at present and that it will also open the door for
exciting new robotic applications in bio-technology and semiconductor industries.

The proposed project on development of high precision robotic laser systems is expected to have a significant impact at
many levels. This project concerns the development of a novel vision system and nozzle assembly as a generic product
that can be mounted on any robot with fibre delivered laser. This project is not limited to one specific application of flexible
laser processing tools, but designed to have a wide range of applications and is expected to open up opportunities to be
applied to a variety of problems in modern manufacturing.
At a global level, it addresses the need for an environmentally sustainable flexible manufacturing tool, by providing an
attractive alternative to current CNC based manufacturing tools that are heavy, expensive and use more resources
compared to FlexLase (e.g. a laser processing tool based on robot weights 18 times less than a CNC laser processing tool,
consuming 12 times less energy). Implementation of robot based FlexLase system will result in a saving of 4.3 tonne of
steel per system (compared to a CNC based system) which takes 2700MJ/ton to produce. The development and
implementation of this flexible robotic system will reduce the number of different machine tools needed in a manufacturing
company. More importantly, the proposed flexible robotic cell can easily accommodate any change of components (e.g.
geometry, size; shape complexity), which may not be the case with CNC based machine tools.
At the national level, the output of the project has the potential to stimulate UK industries and facilitate job creation. The
immediate beneficiaries of FlexLase technology will be SMEs in the aerospace supply chain, using lasers for drilling of
aerospace components. Drawbacks associated with the traditional manufacturing process restrict the affordability of CNC
based machine tools within UK SMEs. The outcome of the project will enable UK manufacturing industries to access stateof-
the-art FlexLase technology and will allow UK industries to be competitive. This will stimulate the entire market sector,
will attract new investment and will provide a boost to the UK economy as a whole. The current laser market in the UK is
estimated at ~£332m with envisaged annual growth of ~7.2% over the next 5 year period. FlexLase aims to address ~20%
of the UK's market over the first two years of its implementation, which would results in at least £12m of savings per year to
UK economy (in terms of capital and energy cost).
Social benefits range from new UK jobs in the HVM industry, to contributing to a sustainable use of resources. Successful
implementation of FlexLase will significantly reduce the capital expenditure which will facilitate the intake of manpower and
increased job opportunities. One job per 5 machines (with a cost saving of ~£2.5m) can result in around 20 new jobs in the
first year of its implementation.