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The development of 3D soft‐robotic components is currently hindered by material limitations associated with conventional 3D printing techniques. To overcome this challenge, an indirect 3D printing approach based on the fabrication of 3D printed sacrificial templates is proposed. High‐resolution micromolds produced by direct laser writing are infused with polymers and then dissolved, leading to the final 3D printed soft microstructures. This method is used to indirectly print 3D and 4D soft microrobots. The versatility of this technique is shown through the fabrication and actuation of gelatin helices filled with magnetic nanoparticles. In addition, it is shown 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. [ABSTRACT FROM AUTHOR]

We describe a double template-assisted electrodeposition of porous metal microstructures. The method combines two-dimensional photolithography and electrophoretic assembly of polystyrene beads, in order to confine the electrochemical growth of a porous magnetic cobalt–nickel alloy within well-defined microscale boundaries. Polystyrene beads are electrophoretically deposited onto a sulfonate derivatized gold substrate where a patterned photoresist layer (first template) is applied. The polystyrene beads trapped in the first template act as the second template, and cobalt–nickel alloy is electrochemically grown through the voids between the beads. After removal of both templates, magnetic microstructures with well-defined shapes and porosity are successfully obtained. Additionally, we demonstrate the capabilities of these magnetic microstructures as wireless cargo microtransporters by loading their pores with a stimulus-responsive hydrogel. Magnetic manipulation experiments are also demonstrated. [ABSTRACT FROM AUTHOR]