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Additive manufacturing: impact on the engineering design process

Arup’s recent work on the use of additive manufacturing (AM) – also known as 3D printing – for metal structural elements has helped us identify the main challenges surrounding the large-scale application of the AM technique. Identifying design solutions that make best use of any new production technique is difficult at first, as the appropriate support tools are usually not yet in place, and designing for production quantities rather than prototyping adds a whole new layer of complexity.  Stepping through the design process to create an AM alternative for an existing design reveals that many design decisions are based on traditional, non-additive thinking, including design constraints, separation of functionalities, standard materials and their characteristics.   Just understanding the design freedoms that AM can offer is not enough to allow in-depth understanding of the potential wider influence of AM on our total design process.

For this project we focused the impact of AM production techniques on the way design engineers work. AM is a collective name for many different additive production techniques, using a diverse range of materials from plastics and concrete to metal and ceramics. We looked at five main design aspects including problem analysis, creating ideas, selecting an idea, design development and communication. For each of these, we considered the opportunities and potential pitfalls that additive manufacturing offers.

Designing for additive manufacturing (AM) requires more skills, not fewer. AM is not just a different production technique, it is a fundamentally different approach that influences how we should think, what we need to know, how we should work, and what we can make.

Due to the additive character of the production technique, there are great benefits of depositing material only where it is really needed. AM can have a significant influence on costs in many phases, including production, transport, building on site, re-use and recycling. We recommend taking the whole lifespan of a product into account when comparing the benefit-cost of AM with that of traditional production techniques.

The challenges of using AM to its best advantage do not usually arise from any limitations in the technique itself, but from the sheer range of potential possibilities arising from AM.

Focusing on the main differentiators of AM relative to traditional methods, we have created a decision flowchart that can help at the early stage of a project to define whether AM could be considered a realistic production technique for that project. Comments and remarks gathered facilitate the application of additive manufacturing in the design process, pointing directly to the issues that need to be addressed to maximise the likelihood of successfully implementing AM.

Through awareness of the main differences between the traditional design process and the one employing additive manufacturing (AM), we are able to identify any potential risks of applying AM in a new production role and prepare a relevant mitigation strategy. We continue to explore the potential benefits of additive manufacturing and, by looking at both opportunities and limitations, we are able to provide advice on what is feasible and useful.