The Science Café is a chance to informally explore the latest ideas in science and technology and debate the issues. All are welcome.

May 9th. 3D-printing: Manufacturing for the Masses

Adrian Bowyer, RepRap Ltd

3D printing is about thirty-five years old. It has two key characteristics: it is very slow, and it is very easy to use. And now that all the patents on it are expiring, it is also becoming very low cost. These characteristics are the fundamental ones needed for a distributed technology – a technology that it makes more sense for individuals and small groups to own than to gather together in big economies-of-scale factories.

The RepRap Project is the main reason for the falling costs of 3D printing. But it was not primarily established as a 3D-printing project. It was established to make a useful self-replicating machine. 3D printing was merely the most appropriate technology to use for self-replication.

After the fundamental interactions of physics, self-replication is the most powerful phenomenon that there is. It has transformed this entire planet, which has been knee-deep in self-replicating machines for the last three and a half billion years. (Indeed, your very knees are made out of self-replicating machines.) And, driven by the inexorable operation of Darwin’s Law, it is also the most efficient method of production that we know.

This talk will be about the introduction of open-source self-replicating machines as a primary means of engineering production, and the possible social and economic consequences of you (and everyone else) making many of the things you need for yourself rather than buying them.

Download the slides from the talk: PDF (5.4MB)

Links: Adrian Bowyer & RepRap Ltd


April 11th: Sustainable concrete? – reducing the global impact of a crucial building material

John Orr, Lecturer in  Civil Engineering, University of Bath

Concrete is the world’s most widely used man made material (1.9m3 per person on the planet in 2015). Created by combining dry materials with water, concrete starts its life as a mouldable fluid and can be cast into almost any shape, before it sets like rock. It is incredibly versatile, architecturally and structurally attractive, and can be used in almost any construction project.

Yet the unique fluidity of concrete is seldom capitalized on, and instead concrete is cast into the simple variety of linear shapes that we see in our building structures today. Such forms are rarely optimal, with the result that in a typical concrete building as much as 40% of concrete is wasted and could be saved through design optimization. Addressing such wastage is a crucial global challenge as the manufacture of cement is highly energy intensive, accounting for more than 5% of global CO2 emissions.

This talk will explore an alternative approach to design and construction, in which the fluidity of concrete is harnessed to cast structures where material is placed only where it is needed. I will explore how my new analysis and optimization methods are combined with novel construction processes to create efficient geometries. The resulting forms represent a new architecture for the sustainable design of concrete structures.

John is an EPSRC Early Career Fellow and Lecturer (Assistant Professor) in Civil Engineering in the Department of Architecture and Civil Engineering at the University of Bath. His teaching and research are related to sustainable construction, with emphasis placed on concrete, and structural optimisation.

Link: John Orr

Download the slides from the talk: PDF (12.7MB)


14th March: Black Holes – Science Fact or Fiction?

Carole Mundell Professor of Extragalactic Astronomy Physics, University of Bath

An observational astrophysicist, Carole began her research career as a radio astronomer at Jodrell Bank Observatory. She then diversified to exploit international ground- and space-based facilities across the electromagnetic spectrum with the goal of understanding cosmic black holes and their environments.

Following two years at the University of Maryland, Carole brought a Royal Society University Research Fellowship to Liverpool John Moores University where she built and led an international team specializing in catching the fast-fading light from gamma ray bursts – the most powerful explosions in the Universe.

She was appointed to a Professorship in 2007 and currently holds a Royal Society Wolfson Research Merit Award (2011-2016) for the study of black hole-driven explosions and the dynamic Universe.


Carole on BBC Breakfast discussing Rossetta’s images of comet 67P

Link: Carole Mundell