26 April 2021
To be honest, it's a simple video: a sheet of plastic with large vertical ridges is being pushed together. With the mounting force, kinks pop up in the ridges. First, one kink in one ridge, then another, and so on. When the force decreases again, the ridges pop away, but not always in the order that they appeared.
The mechanical metamaterials research group made a diagram that charts the separate kink configurations, including arrows indicating which configurations can transform into each other.
'You could consider the route through several configurations a calculation of sorts', says Van Hecke. That way, even a simple sheet being crumpled will have a hidden calculation power. The ERC grant provides the opportunity to build on this line of research, providing funding for three PhD students and three postdocs.
'The idea grew out of earlier research lines', says Van Hecke, whose research is taking place at Leiden University as well as at the Amsterdam based AMOLF institute. His group researches mechanical metamaterials, constructions of pliable materials which can fold in ways that have been programmed into the material. 'This folding happens in a number of pre-programmed steps, but I realized that not only metamaterials go through such steps', says Van Hecke.
'This got me thinking: which kinds of material behaviour can you obtain when the steps depend on each other. First, it was only asking myself: why don't I know this already?
But it turned out that the rest of science didn't know either. 'There has been research into crumpling, but that is from a more global physics perspective, and we don't really understand it. I thought it would be interesting to look very precisely at the individual crumpling steps.'
At the same time, a number of colleagues were researching memory effect, in which the deformation of a material depends on earlier steps. 'Memory is of course an element of computing, but why wouldn't you take this thought further, and consider the deformation of materials as a form of information processing? Perhaps, you could design materials which do calculations by deforming.'
The research group has entered that road, which lead to a piece of rubber that can count to ten (yet to be published). 'It's not that I think materials could compete with ordinary computers', says Van Hecke, 'it's more about understanding in a fundamental way how the deforming of materials can be understood as information processing.'
No doubt, there will be applications, Van Hecke expects. Ideas from earlier metamaterial reserach are already being applied in the design of stronger medical implants and better fitting prostheses. 'But it's really impossible to predict in advance what these applications will be.'