A Voxel‐Based Approach for the Generation of Advanced Kinematics at the Microscale

摘要

In soft robotics, the ability to generate advanced kinematics is a necessary step toward any more sophisticated tasks such as microobject manipulation, locomotion, or configuration changes. To this end, herein, a modular voxel‐based methodology adaptable to any scale and with any soft transducer is presented. The methodology is implemented at the micrometer scale with a one‐step fabrication process. An innovative gray‐tone lithography method using the two‐photon polymerization of photosensitive poly( N ‐isopropylacrylamide) hydrogel is developed to print the voxels. Bending, compression, and twisting voxels are designed, printed, and characterized. A voxel consists of an isotropically shrinking active material reinforced adequately with a passive pattern. Each elementary voxel deforms along one degree of freedom and is a building block for superstructures able of advanced kinematics. With a side length of 40 μm, the bending voxel achieves a bending angle of 25º or curvature of . The compression voxel reaches an actuation strain of 40%, and the twisting voxel bends up to 18º. Advanced kinematics are demonstrated by printing complex structures composed of multiple elementary voxels. Herein, a foundation toward soft microrobots capable of performing complex tasks is constituted.