Indirect 3D and 4D Printing of Soft Robotic Microstructures

Abstract

The development of 3D soft-robotic components is currently hindered by material limitations associated with conventional 3D printing techniques. To overcome this challenge, we propose an indirect 3D printing approach based on the fabrication of 3D printed sacrificial templates.High-resolution micromolds produced by direct laser writing were infused with polymers and then dissolved, leading to the final 3D printed soft microstructures. We used this method to indirectly print 3D and 4D soft-microrobots. The versatility of our technique is shown through the fabrication and actuation of gelatin helices filled with magnetic nanoparticles. In addition, we show that stent-like microstructures with shape memory properties can be manufactured with minimum features of 5 µm, which is 40 times smaller than those reported to date. In summary, the utilization of this technique can overcome obstacles associated with the fabrication of soft microrobots and surgical tools for minimally invasive surgery.

Medical Micro/Nanorobots in Precision Medicine

“…[39,40] The advantage of these methods is that there are many different types of commercially available microtemplates ranging from polymeric to metallic beads, with more recent examples of the use of biological and bioinspired templates. [41][42][43] Other designs with more complex structures, such as microcoils or sophisticated geometries have been built using advanced techniques, including 3D printing, [44][45][46][47][48] glancing angle deposition, [49][50][51][52] and rolled-up lithography. [53][54][55] These novel techniques offer new design capabilities allowing to add functionality by design.…”

“…Other designs with more complex structures, such as microcoils or sophisticated geometries have been built using advanced techniques, including 3D printing, [ 44–48 ] glancing angle deposition, [ 49–52 ] and rolled‐up lithography. [ 53–55 ] These novel techniques offer new design capabilities allowing to add functionality by design.…”

Artificial Biosystems by Printing Biology

“…Printing techniques [72,73] embrace a range of different specific approaches, spanning between contact (e.g. extrusion/fused deposition) and non-contact methods (e.g.…”

Fabrication and Magnetic Actuation of 3D‐Microprinted Multifunctional Hybrid Microstructures

“…Thus, to integrate the opaque magnetic material into the printed object, three approaches have been reported: the dilution of magnetic nanoparticles in the photoresist, [ 15–17,27 ] the deposition of thin magnetic films or particles after printing and washing, [ 5,12–14 ] or more complex and indirect, the filling of a printed mold. [ 28–30 ]…”