For the 2017 Ramboll Leadership Conference in Copenhagen, which took place on the 22nd and 23rd of January, RCD was involved in a collaboration between the Transport and Buildings departments to design and construct a ‘bridge’ installation between their respective stands. We had a little over a month to develop and manufacture the design so timescales were tight and we had several key criteria to consider – the bridge was to support a model train running between the two stands (in reference to the Holmestrand Mountain Station project), it needed to be light and easily demountable enough for us to carry from London to Copenhagen, build in an afternoon, break down in an hour and then return back to London (for later re-assembly in our home office). We also wanted it to form an interactive part of the conference rather than merely being a static display piece.
We approached the project the same way we would any other – pulling together a team with relevant expertise, brainstorming ideas, analysing and developing them. For the interactive element, we realised that business cards made an ideal impromptu craft material and were one of the few things we could rely on most of the attendees to be bringing with them. The decision was thus made to allow people at the conference to leave their business card, folded into a specific 3D form, as part of the bridge’s cladding.
Design of the overall structure progressed rapidly through several meetings, based around a flexible parametric Grasshopper model developed by RCD that allowed for collaboration around real-time adjustments to the geometry. After the examination of several options we settled on a timber shell/arch structure as an aesthetically pleasing, lightweight, robust solution that would reference both Ramboll UK’s expertise in timber structures and previous RCD project the TRADA pavillion and which could be rapidly manufactured and assembled.
Throughout the development of the bridge the geometry was exported to and analysed in MIDAS by the London Bridges team in order to make sure the design was structurally feasible and to guide further refinement of the form and material thicknesses. Additionally preliminary samples of sections of the bridge were laser cut to allow us to physically examine and test the manufacturing process and connection detail design.
In order to enable the bridge to be rapidly assembled and disassembled we wanted to avoid the use of adhesives or mechanical fixings. The connections were therefore designed as simple slotted plates, held in place laterally by a matching slot in one of the plates they joined and restrained laterally by small standard ‘U’-shaped clips, all cut from the same 6mm plywood as the rest of the structure. The nature of the shell form meant that the angle between each panel (per quarter of the structure) was different. Generation of these connector pieces was thus integrated into the Grasshopper model in order to determine cutting patterns for each connector and panel, each of which was also automatically labelled with a number to be engraved onto the inner side of each piece to allow easy identification of which pieces connected together during construction. Each connector also incorporated a small hole through which the line which would support the bridge deck could be passed.
The slots into which business cards could be placed were likewise incorporated into the Grasshopper model, arranged so as to fit in the maximum amount of business cards without compromising the structural integrity of the panels. Due to the variety of panel shapes and sizes no one placement algorithm was found to give consistently good results, consequently two separate arrangement algorithms were utilised to determine slot placement and the best of the two automatically selected for each panel to give the final arrangement.
Foundation design is a key component of any project and this one was no different. Two pedestals were designed to support the feet of the bridge. As an arch, the natural reaction of the structure under load was to try and push outwards. To resist these thrusts without having to tie the base of the arch together or carry over heavy weights in our luggage, these pedestals contained hidden compartments to conceal bottles of water which were procured on-site and provided the necessary ballast.
This being a conference for engineers in Denmark, it was a foregone conclusion that the train the bridge would carry should be made out of LEGO. The train in question came with a seven-speed remote control, however to avoid having to manually drive the train for two days straight it also fell to RCD to automate this by hacking the controller. The rotary dial which controlled the train’s speed produced different signals when turned clockwise or anticlockwise – instructing the train to accelerate and decelerate. By hooking up these contacts to an Arduino Uno board programmed to mimic these impulse patterns it was possible to control the train’s movements programmatically and have it moving backwards and forwards across the bridge without human intervention. Unfortunately several key wires were damaged in transit, requiring some frantic (but ultimately successful) repair work with a borrowed soldering iron the day before the conference.
Besides that, the bridge made it to Copenhagen without damage and was erected successfully at the conference. It proved very popular with the conference attendees, becoming packed with business cards by the end of the second day and successfully demonstrating the capabilities of computational design and collaboration to the wider business.
“Our team was made up of people with different skills sets and backgrounds, who were unified by a desire to create something unique. The bridge was a success because all team members contributed their technical expertise, yet listened to and challenged each other to continually improve and refine the design.
This project shows that having the right mix of people with a passion for a common goal can generate great design in a short period of time.” – Sarah Ord, Project Manager
“The Transport and Buildings teams collaborated seamlessly, bringing our respective strengths together created a more complete and superior design
“The use of parametric modelling and rapid prototyping and manufacture released the team’s time to concentrate on the creative design of the bridge through swift iterations. Designing and building the bridge in one month would not be possible without this approach” – Ollie Wildman, Director
“I worked on the structural analysis of the bridge ensuring that the design was robust enough to stand and carry the applied loads. It was great to have worked on such an innovative project and of course it could not have been done without this amazing and passionate team. Overall it was a brilliant experience and I am looking forward to work on similar stuff in the future!” – Neophytos Yiannakou, Bridge Engineer
“Parametric modelling has enabled quick optimisation and adjustment of the bridge geometry, making it easier to model and analyse. In a short period of time we were ready to print and test a first prototype, which has been key to meet the project deadline
“It has been a wonderful experience to design and actually build the bridge with such a diverse and motivated team. It is in projects like this where you realise the potential of combining different disciplines.” – Xavier Echegaray Jaile, Bridge Engineer
The complete bridge is now on display in the reception area of Ramboll’s London offices at 240 Blackfriars Road.