fig3

Figure 3. Design strategies of continuous and encapsulated structures, as well as modular and reconfigurable structures. (A) The hydrogel-coated containment capsule features a hierarchical core-shell architecture with remotely controlled thermal ablation capabilities via magnetic robotic arm manipulation under X-ray imaging guidance. Reprinted with permission from^[123]. Copyright 2025, Oxford University Press; (B) Schematic illustration (i) and images (ii) of tubular robot expansion and peristaltic motion enabled by liquid-gas phase transition. Reprinted with permission from^[126]. Copyright 2024, Springer Nature; (C) pH-responsive jack-in-the-box device deploys self-extending microneedle arrays to penetrate mucus and sustain localized drug release. Reprinted with permission from^[131]. Copyright 2022, American Association for the Advancement of Science; (D) Self-folding chain exhibits modular self-folding architecture that transforms from linear configuration into large functional assemblies with multiple domains at the catheter tip. Reprinted with permission from^[133]. Copyright 2023, Springer Nature; (E) The low-friction soft robot incorporates densely arranged cone structures with hydrophobic surface decoration to achieve ultra-low friction locomotion in viscous GI environments. Reprinted with permission from^[53]. Copyright 2024, Beijing Institute of Technology Press. GI: Gastrointestinal.