Rapid Parallel Fabrication and Control of Diverse Microrobotic Structures with Magnetic Functionalization.

Building and validating functional robot bodies at the milli- and microscale remains a challenge in studying and imitating living behavior. Traditional fabrication methods, such as 3D printing, often require multiple steps, are time-consuming, and may not be cost-effective. To overcome these limitations, photolithographic methods, commonly used in microchip manufacturing and 3D printing of photoreactive materials, offer advantages, including high precision, scalability, repeatability, and rapid production. Here, we present a method for the rapid, parallel fabrication of magnetically functionalized hydrogel-based robots. With our device, the Magni-DOME, robots can be fabricated and directly characterized within the same setup and production cycle, thanks to its integration of high-precision projection and magnetic control for both fabrication and actuation. This approach enables the scalable production of diverse photoreactive hydrogel-based structures by combining photolithography with magnetic patterning. We demonstrate the utility of this method by fabricating a variety of magnetic hydrogel-based robots with different shapes and sizes in parallel and validating the behavior of selected designs.