Design for Hybrid Manufacture - DHARMA

Manufacturing in the UK is undergoing significant transitions and transformations in terms of new emerging technologies and methods. The traditional view of using a range of disparate processes in a precisely defined logical sequence of steps is now being challenged by the continued emergence and growth of metal additive layer technologies, most commonly termed additive manufacturing. With projected growth in this sector increasing (current annual compound growth rate is 34.9%), it's continued involvement in manufacturing is set to increase considerably. However, the major bottleneck is the significant additional finishing processes required after initial generation of the component. The streamlined and integrated combination of AM and subtractive process is now being termed hybrid manufacture.

Current design for manufacture methods are well-established techniques that allow designs to be adapted to enable efficient production using traditional linear manufacturing approaches. However these current state of the art methods are not directly applicable to new emerging manufacturing techniques, without significant modification and adaption. This will impede the generation and uptake of novel and emerging manufacturing processes, further stagnating design.

Project DHarMa (Design for Hybrid Manufacture) aims to deliver a disruptive, design rationale and process that is specifically targeted at enhanced utilisation of combined additive and subtractive technologies in the form of hybrid manufacture (HM). This will be achieved by undertaking systematic, quantitative and qualitative research that will focus on generating a design for hybrid manufacturing process, based on identified design features and geometry classifications in seamless conjunction with hybrid manufacturing key performance indices and a manufacturing capability framework.

DHarMa will incorporate specific additive and subtractive manufacturing information constructs in conjunction with design feature and geometry relationships and attributes. Essentially this will integrate and categorise part specific design and manufacturing information and will be used to generate the DHarMa process.

Designers will have a powerful tool that will enable them to tailor and adapt their designs to be manufactured using a combination of additive and subtractive technologies. Unlike conventional manufacturing that has significant limitations in terms of features and geometries that can be correctly generated, AM un-constrains manufacturing with the direct capability to create highly complex features and geometries that would be typically inaccessible using conventional methods (for example, dematerialised internal thin walled features). This affords the designer more design freedom and flexibility, thus empowering them to create new innovative products without the need to be constrained by a rigid set of conventional manufacturing protocols. This feasibility project will provide the initial study in to the generation of a design process that will enable parts to be specifically designed for manufacture using a HM approach. This will initially be based on prismatic designs that will be applied to HM.

1)Engineering, manufacturing & wealth creation
Renishaw are the sole manufactures of metal additive layer (MAL) machines in the UK. They are actively developing hybrid manufacturing (HM) solutions using a combination of MAL & subtractive methods. However, no specific design process to capitalise on HM exists. A new project recently funded through Innovate UK entitled FALCON will develop a new HM approach based on combined MAL & subtractive technologies. DHarMa will allow Renishaw to design parts specifically to be manufactured using the FALCON HM method. This will allow for significantly reduced design intent loss with optimal manufacturing. DHarMa will initiate generation of a new design for HM process enabling Renishaw to cement their nationally leading position in the emerging domain of HM for coming decades, and is timely as the use of emerging manufacturing is continually increasing across all industrial sectors.

Moog is a world leader in electro hydraulic servo valves (EHSVs) for aerospace. Moog currently manufacture EHSVs using in excess of 30 independent processes. Using MAL to generate the near net geometry of the EHSV results in a 26% weight saving equating to a fuel saving of $8500 per year per aircraft. The EHSV's are then finish machined. Whilst this approach has the potential to reduce current manufacturing cost by 40%, EHSV's are not designed to be manufactured using a HM approach, thus there is a significant proportion of parts that fail during manufacture. DHarMa will provide a new design process enabling EHSV's to be designed for HM.
Generation of a new design process will allow designers to create designs that can be specifically manufactured using new emerging HM. The Government Office of Science's 2011 Foresight Horizon Report on "Technology & Innovation Futures: UK Growth Opportunities for the 2020's" highlights that novel technology approaches is the key change that will transform UK manufacturing into a 21 century lead.

2) Aerospace
The UK's Aerospace Technology Strategy Group expects $3 trillion of civil aircraft to be sold in the next 20 years and estimates that the UK has the second largest aerospace industry in the World (£23billion turnover in 2010). Whilst uptake of HM is beginning to emerge in the aerospace sector, design of parts for HM does not exist. DHarMa will be introduced within aerospace industries to enable part design for HM.

3) Medical
The UK medical industry is worth $10billion and growing. Renishaw will use outputs form DHarMa to enable efficient design of medical parts for optimised manufacture using a HM strategy.

4) Environment & social
The reduction in manufacturing process chain from a number of co-dependent processes to a combination of MAL & subtractive methods will reduce environmental impact of manufacturing (up to a 40% energy reduction), however, the use of current DfM methods will still hinder full optimal use of this emerging technology. The generation of a new intelligent DfM method targeted specifically at HM will empower designers to create designs that can capitalise on HM capabilities with reduced design intent loss, and enable more efficient manufacturing. DHarMa will provide a logical process for designing of parts specifically for HM, which will reduce the environmental impact of conventional co-dependent processes.

5) Investigators & Researchers
The investigators & researche associates (RA) will benefit from the experience of applying their research skills in a research project with collaborators who are highly skilled in their own particular fields. This synergy will lead to a new vision for design, patented co-inventions and to novel results and co-authored publications. The RA's will benefit from the experience of working on a TRL 0-2 research project, which will be valuable to their future careers either in industry or academia. The project is likely to highlight research areas for future investigations both nationally & internationally.