Engineers across European universities have developed a mechatronic metamaterial that behaves as a time crystal, pulsing in unison and organizing its own movement despite random disturbances. The findings were published on October 14, 2026, in the journal Nature by researchers from the University of Birmingham alongside teams from Amsterdam, Lyon, Delft, Leiden, and Cambridge.
Time crystals represent an unusual form of matter where particles continuously move in regular, repeating cycles. In this experimental system, the moving parts are not microscopic molecules or atoms. Instead, the team constructed the material using robots, combining elastic structures, sensors, electronics, and actuators so that neighboring components can directly influence one another.
The central mechanism behind this time-crystalline behavior is making interactions between components nonreciprocal, meaning one component’s response to another does not need to be mirrored in reverse. According to Phys, this broken reciprocity allows small local vibrations to progressively grow in wavelength, period, and amplitude until the entire structure reaches a globally synchronized state. The work illustrates spontaneous organization, comparing the process to musicians gradually finding the same beat.
Honeycomb Grids and Motorized Rings Test Collective Motion
To test how these systems scale and behave under physical constraints, the research team built two distinct experimental setups. First, they constructed a two-dimensional honeycomb material made from 37 active units. When pushed beyond a stability threshold, individual units began self-oscillating at roughly 30 Hz. Over time, longer waves took over until the entire material oscillated collectively.
The researchers also built an elastic ring containing 24 motorized units. Initially, higher-frequency deformation patterns appeared around the ring before progressively combining into larger patterns until the ring settled into a slow collective cycle. Experiments and mathematical models both showed that random disturbances do not disrupt this collective order as the material scales up, making the repeating pattern very stable.
Custom Lorentz Actuators Drive Multifunctional Robotics
The research originated in an Amsterdam group led by Dr. Corentin Coulais. The experimental metamaterials incorporate more than 100 sensors and actuators alongside three-dimensional printed components and custom-made Lorentz actuators designed to convert electrical energy into mechanical motion. Interns assembled metamaterials featuring more than 100 embedded sensors and actuators, with each actuator requiring over 20 points of glue. Dr. Coulais also highlighted the collaborative effort involved in production, noting assistance from the university’s Technology Centre in Amsterdam.
With applications in mind, we have also started to think about making one material support several distinct, stable patterns of motion. Could we switch between these patterns and use each one for a different robotic function, such as a different shape change or direction of movement?
Jonas Veenstra, Co-lead author
Veenstra started the research as a PhD student at Amsterdam and is now a postdoctoral fellow at ENS Lyon. He noted that instead of designing a separate structure for every individual task, engineers could use the different modes of a single material to achieve various behaviors. This approach aims to create biology-inspired robotics where coordinated actions emerge from carefully designed interactions between building blocks rather than commands from a central controller.
Researchers Aim to Develop 3D Active Materials
Moving forward, the research team aims to develop three-dimensional active materials that offer additional ways for components to interact, including shearing, bending, and twisting. Investigators hope to understand how wave coarsening behaves in three dimensions and how it can be harnessed to control shape changes in self-supporting structures. Phys reported that wave coarsening could ultimately be exploited to control shape changes and directed motion across robotics, active matter, and optomechanics.