Metrology for precision and additive manufacturing

Since the beginning of humanity our societies have been based on commerce, i.e. we make things and we sell them to other people. Relatively simple beginnings led to the Industrial Revolution and now to the technological age. Over-generalising, the Far East are currently the masters of mass manufacture and the West are (or wish to be) the masters of advanced manufacture - the production of high-value goods, often involving a significant degree of innovation. To be able to manufacture goods in a cost-effective, environmentally-sustainable manner, quality control procedures are required. And quality control in turn requires an appropriate measurement infrastructure to be in place. It is a sub-set of this measurement infrastructure that is the subject of this fellowship.

The UK government has been investing heavily in advanced manufacturing. In the academic arena, there are the sixteen EPSRC Centres of Innovative Manufacturing. To ease the pain of transferring academic research to the manufacturing sector, there are the seven High-Value Manufacturing Catapults (the Manufacturing Technology Centre being the main one of note here). For industry, there are a number of funding initiatives and tax breaks. To support this burgeoning UK advanced manufacturing infrastructure, there are a small number of academic centres for metrology - those based at Huddersfield and Bath are the main players. And, at the top of the measurement tree, there is the world-class National Physical Laboratory - a centre of excellence in metrology. But, there are still some gaps in the manufacturing metrology research jigsaw, and the aim of this fellowship is to plug those gaps.

Coordinate metrology has been used for decades in the manufacturing industry as the most dominant form of process control, usually employing tactile coordinate measuring machines (CMMs). However, due to the slow speed of tactile systems and the fact that they can only take a limited amount of points, optical CMMs are starting to flourish. On the smaller scale, there are many optical surface measuring devices that tend to be used off-line in industry. When making small, high-precision, complex components, with difficult to access geometries, it is a combination of the surface measurement systems and the CMMs that is required. This requirement is one of the main aims of the fellowship - to develop a suite of fast, high-accuracy, non-contact measurement systems, which can be employed in industry. These principles will also be applied to the field of additive manufacturing - a new paradigm in manufacturing which is seeing significant government support and, in some cases, media hype. As with high-precision components, a coordinate metrology infrastructure for additive manufacturing is required, in many cases in-line to allow direct feedback to the manufacturing process. This is the second field of metrology that the fellowship will address.

The outputs of the fellowship will be in the form of academic publications; new measurement instruments, along with new ways to use existing instruments; methods to allow manufacturers to verify the performance of their instruments; and the necessary pre-normative work that will lead to specification standards in the two fields (currently lacking). The academic world will benefit from the fundamental nature of elements of the research, and the industrial manufacturing world will benefit from the techniques developed and routes to standardisation. But, ultimately, it will be the UK citizens that will reap the greatest benefit in terms of new and enhanced products, and the wealth creation potential from precision and additive manufacturing.

The aim of the fellowship is to undertake early stage, fundamental manufacturing research to establish new metrology technologies demanded for the effective control of manufacturing of emerging products. Advanced manufacturing is only possible with a suitable quality control system in place, and this in turn requires a suitable metrology infrastructure. Currently, there are two surface metrology camps: 1) surface topography measurement, and 2) coordinate metrology. Whilst these two camps have had a significant impact on manufacturing over the past few decades (for example, the tactile CMM revolutionised the automotive industry), there are still a number of dimensional measurement issues that need to be addressed. This fellowship will address fundamental issues with two remaining areas of research: precision coordinate metrology and metrology for additive manufacturing. Therefore, the work in the fellowship will be of significant benefit to industry interested in the development, design and manufacture of complex high-value products, such as aerospace engine components, customised medical devices and complex packaging solutions. Such products all require tight tolerances to be maintained, requiring high levels of quality control, and present a serious challenge to manufacturers. In addition, metrology will play a pivotal role in effective process optimisation and control for the development and successful application of additive manufacturing. The fundamental metrology know-how created in this fellowship will allow more responsive and more accurate metrology systems to support scientific development, engineering design and manufacturing.

This fellowship will deliver the fundamental and underpinning metrology necessary for manufacturing with precision or additive manufactured components, and will lead to the engineering of new functions and attributes into a product, such as lower mass, better fuel efficiency (through tighter tolerances) and easily-recycled/replaced parts. The project will also provide a metrological platform for implementation of coordinate and surface measurement instrumentation into the manufacturing chain by matching the design tolerances with appropriate measurement uncertainties. At the end of the fellowship, a number of industrial measurement systems and methods will be available to industry, and in-line control of complex processes will become feasible. The IP developed will also be exploited through the instrument manufacturing partners in the project, potentially resulting in several new commercial instruments. The project has real technological and scientific relevance and, therefore, a large potential to create a positive impact on people's lives through improvements in fields as diverse as medicine, transport, energy conservation and leisure products.

Developing future engineers
It is recognised that the involvement of undergraduate and postgraduate students with the project team represents a significant impact. These students will be the next generation of metrologists, researchers and engineers; as such they are well placed to transfer learning from the project into industry or other areas of engineering research. To closely support complimentary research tasks, seven PhD students will be trained as part of the project. These students will develop highly sought-after transferable research skills, useful to both academic and industrial applications. In addition to this core activity, there will be opportunities for MSc projects, group design projects, literature review projects, and MEng/BEng final year projects. Based on these opportunities, the academic team will work closely with the project's industrial partners to produce a range of exciting project themes.