3D Printing A Bridge With A Twin
The world’s first 3D-printed steel bridge showcases technology that could reduce the amount of material used in structures. It has a network of sensors that continuously feed data into a ‘digital twin’; that will monitor how the bridge behaves over time and help refine the design of similar structures in future. Hugh Ferguson reports and looks at how a similar approach to monitoring is being adopted across civil engineering projects.
The origins of this bridge lie within a small creative design studio in Amsterdam, Joris Laarman Lab, headed by designer and artist Joris Laarman. In about 2014, excited by opportunities presented by emerging technologies, the team decided to develop designs in 3D-printed stainless steel. This presented an immediate challenge: no-one had before produced large steel objects using 3D printing or additive manufacturing. The process requires molten metal to be deposited in multiple layers. At the time, there were already tools for metal inert gas (MIG) welding. In this arc welding process, a continuous solid wire – usually 1.2 millimetre in diameter – is electrically heated and fed from a welding gun. There were also robots on which the tools could be mounted. However, no-one had used robots with MIG welding. Robots were generally used for repetitive ‘pick and place’ tasks, rather than complex welding control.