Image courtesy of MX3D and Adriaan de Groot

In 2015, a company called MX3D started working on an ambitious project: printing a bridge. The bridge was recently presented in its final form at the Dutch Design Week in Eindhoven. Right there on the bridge, we bumped into Kars Alfrink. He kept looking back and forth between us and his tablet. “Go on, jump!”, he told us enthusiastically, and we were happy to comply; the bridge bounced nicely. The screen in his hands immediately started generating a graph. “That’s your jump,” Kars explained, pointing to the graph on the display.

The first and so far last time someone made the effort to measure my jump was at a sports day back in primary school. The only thing that mattered was the distance between the starting line and the mark my feet made in the sand. Now I was looking at push-off, impact, time, pressure, rhythm, cadence, weight and so many other derivative variables. My jump was not just more-or-less measured, but scanned, dissected, in fact examined at an almost microscopic level. By a bridge.

Kars Alfrink is a researcher at Delft University of Technology working on the BRIDE project, which is studying the world’s first 3D-printed bridge. “The bridge is a sensor. This means that the bridge actually exists twice: once in the digital world and the second time in a digital model, as a digital twin. Thanks to dozens of sensors on the physical bridge, the digital bridge also behaves like an exact copy of real bridge. If you jump on the real bridge, a virtual person also jumps on the digital bridge.”

3D-printing a bridge is a huge accomplishment already, but then also configuring the bridge as a sensor, as a data source, paves the way for a world of new opportunities and ethical questions. These questions are the field that Kars is researching.

“We are talking about a smart bridge, but what makes it smart? Smart for the makers, the builders, the users, the city? What effects will it have on how we make bridges? How will citizens understand what the bridge does? How do you communicate that?” Kars emphasizes that the project has been primed with the agenda, goals and ideas of the makers and designers – a predominantly technical agenda. In a little while, when the bridge connects two waterfronts, it will be possible to access a live view of all the pedestrians crossing the water. How the city will use this data for interventions in the public space is a question that remains unanswered for now. We need to start asking and answering these social questions now. Everyone agrees that something needs to be done about the hustle and bustle in Amsterdam’s red-light district. But if some of those decisions are based on a sensor in a bridge, how do you explain that to the people involved?

An easy answer to this question would be to make that data available to the public. But that seems to generate a whole series of new dilemmas: who owns the data that the bridge generates? The company that created it? The city, the people living around the bridge, or just plain everybody? How open does the data need to be? And will making the data open to the public actually ensure that the makers of the bridge will be able to provide accountability for their bridge?

“Opening everything up is pointless,” Kars explains. “The amount of data that the bridge generates is so huge that no one can actually do anything with it without having access to specialized computer equipment.” If MX3D applies an abstraction to that data, making it more accessible to citizens, you might be able to see that someone is jumping on the bridge, but not exactly how hard or where on the bridge. However, abstractions also lead to new choices. What do you show – and above all, what don’t you show?

What if making things open to the public doesn’t provide answers to these questions? The best option may still be for the city to have access to the data so it can grant access to other bridge-builders when they want to make a new bridge. The data gathered from the public can be valuable to these parties, and companies do have the resources to process the raw data. That does leave the question of how to involve citizens largely unanswered.

“Maybe citizens want entirely different things from a bridge. In a previous research project, citizens came up with ideas to have the bridge tell stories about the history of the location, or to measure and display the quality of the air and water at that spot, but those ideas were not taken into account when creating this specific design for the bridge.”

A previous design of the bridge was rejected by the city because the bridge could potentially have collapsed if a boat ran into it. The current bridge has been modified to resolve that issue. The rules that we set for bridges in terms of collapse or prevention are the result of years of research, debate and hands-on experience. The current MX3D bridge will be able to make a major contribution to equal rules, standards and knowledge in the digital domain. And then we can finally determine how open the bridge will be.