Miniature soft robots offer excellent safety and deformability, which are highly desirable in applications such as navigation in confined areas or the manipulation of microscale objects. However, it is difficult to manufacture such robots using traditional processes due to the complexity of their design. While rapidly advancing 3D printing technologies offer manufacturing flexibility, it is still challenging to fabricate soft pneumatic robots on millimeter scales due to the difficulty in making microscale voids and channels, which are essential for pneumatic actuation. A generic process flow for systematic and efficient tailoring of the material formulation and key processing parameters for digital light processing‐based 3D printing of miniature pneumatic actuators for soft robots is presented. The process flow includes selection of photoabsorber and material performance characterization to determine the appropriate material formulation and characterizations for curing depth and XY fidelity to identify the combination of exposure time and sliced layer thickness. By applying the tailored results to a self‐built multimaterial 3D printing system, an assortment of miniature soft pneumatic robots with various structures and morphing modes are printed. Furthermore, potential applications of printed miniature actuators are exemplified by a soft debris remover that navigates in a confined space and collects small objects in a hard‐to‐reach position.

A microlens array has become an important micro-optics device in various applications. Compared with traditional manufacturing approaches, digital light processing (DLP)-based printing enables fabrication of complex three-dimensional (3D) geometries and is a possible manufacturing approach for microlens arrays. However, the nature of 3D printing objects by stacking successive 2D patterns formed by discrete pixels leads to coarse surface roughness and makes DLP-based printing unsuccessful in fabricating optical components. Here, we report an oscillation-assisted DLP-based printing approach for fabrication of microlens arrays. An optically smooth surface (about 1 nm surface roughness) is achieved by mechanical oscillation that eliminates the jagged surface formed by discrete pixels, and a 1–3 s single grayscale ultraviolet (UV) exposure that removes the staircase effect. Moreover, computationally designed grayscale UV patterns allow us to fabricate microlenses with various profiles. The proposed approach paves a way to 3D print optical components with high quality, fast speed, and vast flexibility.

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