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Artificial intelligence behind super design for buildings

Computer processing is now so powerful that it can design building structures to such a degree of perfection that even architects and engineers have to throw in the towel. Engineering students are behind the super algorithm that controls it all and may radically change work processes in construction when it is released early next year.

Together with a former classmate from Aarhus University, Lasse Rahbek, MSc Eng. has printed a model of a lattice-shell construction. The model can be used for large canopy constructions like the dome at the British Museum in London.

What is special about the model is that it is very nearly perfect, with optimal properties in terms of weight, strength, rigidity and aesthetic expression.

And a computer program has done all the design and calculation work, which would otherwise have taken several years for an entire army of engineers and architects to complete.

"The computer does very complex analysis work and finds the most advantageous structure with an optimal relationship between geometry and rigidity. This means that the structure is incredibly strong, it has a beautiful shape and it requires minimal use of materials," says Lasse Rahbek, MSc in Engineering in construction.

The idea to work with artificial intelligence in construction came to Lasse while he was working on his Master's thesis, and now he has developed an algorithm for lattice structures that surpasses the human ability to identify complex interconnections.

Darwin behind the perfect lattice shell

The computer-designed lattice shell is based on a genetic algorithm that mimics biological evolution by constantly ensuring that only the best structures are allowed pass on their genes to the next generation.

"The algorithm works as a kind of "survival of the fittest”. It divides the proposed structures into pairs which inherit the good characteristics from each parent. Generation by generation, the lattice shells become better because the computer can keep track of the many possible combinations and identify what works best," says Lasse.

The actual model in the picture has been ‘bred’ through no less than 400 random structure patterns and 100 generations in 18 hours of computer-based calculation work. And in principle it is just one example of the use of artificial intelligence to perform complex design tasks.

According to Lasse, only the imagination limits to how these new algorithms based on Darwin's old theory of evolution can create innovation in all sections of the construction value chain.

Engineering and the computer work together

And what about the engineer? What about the architect? What about their work in the future? Their job will be to feed their computer with information and thereby steer its intelligence towards the result they want to achieve.

Similarly, Lasse has inserted a number of criteria into the current computer program to design lattice shells. These will ensure that the algorithm finds the structures with the best match between weight, rigidity and size of the lattice cells.

"You can weight the various criteria and reward a pattern that has a very low material consumption or looks particularly attractive, for example. You can also set conditions; for example that the rods in the lattice must have a specific length. So you could say that the human brain is still crucial to make sure that the final design proposal fits with the surroundings and the reality around the completed building," says Lasse.

His project is being funded by Boligfonden Kuben. The computer program is scheduled to be taken in the use by architects and consulting engineers at the start of next year.