Flow Casting Soft Shells with Geometrical Complexity and Multifunctionality
Soft shells are ubiquitous in soft devices, e.g., soft robots, wearable sensors, and soft medial replicas. However,
previous widely accepted methods, such as mold casting, dip coating, and additive manufacturing, are limited to thick
shells due to the mold assembly and the large friction during demolding, long processing time for mold dissolution, and
poor scalability, respectively. Here, a facile, robust, and scalable manufacturing technique, named flow casting, to create
soft shells with complex geometries and multifunctionalities is proposed. The method involves a flow-governed layer casting
process and a peel-dominated demolding process. A one-dimensional soft shell is first made with controllable thicknesses
(100-400 µm) and fabricated various soft shells of intricate geometries, including three-branched, circular-shaped, and
exquisite microstructures such as papillae and microgrooves on curved surfaces, with the resolution of feature sizes on the
order of 100 µm. Furthermore, the versatility of this method is demonstrated with a 3D vascular phantom model for a magnetic
robot transporting, microstructured cubic sleeves for enhancing the grasping ability of rigid grippers, and a stretchable
optical waveguide capable of color changing by external mechanical stimuli.
Dongliang Fan, Yuxuan Liao, Wenyu Wu, Ping Zhang, Xin Yang, Renjie Zhu, Yifei Wang, Canhui Yang, and Hongqiang Wang*. Flow Casting Soft Shells with Geometrical Complexity and Multifunctionality. Advanced Materials Technologies , Early Access.