Currently, soft robots face challenges such as low motion efficiency, susceptibility to damage in traditional silicone materials, and difficulty in achieving reproducible manufacturing. To address these issues, we integrate flexible film materials with modular design principles and apply them to soft robotics. Based on the concept of modularity, this study simplifies and decomposes the robot’s motion into three fundamental modules: a thin-film elongation actuator module, a thin-film deflection actuator module, and a connection module. Inspired by the Miura-fold origami technique and traditional lantern contraction, the elongation actuator is designed to produce axial extension of varying lengths under different air pressures. The deflection actuator is modeled after the head expansion mechanism of the pelican eel, enabling deflection movement. The connection module integrates the elongation and deflection modules into a unified structure. The research results show that the elongation actuator achieves an extension length of 118 mm under 50 kPa and can pull a 500 g load during horizontal contraction. The two-layer deflection actuator achieves a deflection angle of 56° at 40 kPa, while the three-layer version reaches 98°. For further demonstration, we subsequently conducted peristaltic soft robot experiments and obstacle avoidance experiments. This study holds significant potential for the development of next-generation multifunctional soft robots.

Building upon previously developed thin-film modular soft actuators for elongation and deflection, this study develops a modular soft robot for pipeline locomotion, addressing insufficient anchoring capability in confined environments. Conventional inflatable airbags typically expand into spindle-shaped geometries, resulting in limited contact length and reduced effective gripping stability. To overcome this issue, a corrugated thin-film gripping actuator is proposed, in which two high-aspect-ratio sub-airbags are arranged above a compression structure to regulate deformation through geometric constraints. Numerical simulation and experimental evaluation were conducted to investigate contact behavior and locomotion performance. Under an input pressure of 30 kPa, the proposed design achieves a contact length of 46 mm, compared to 37 mm for a conventional three-layer airbag configuration under the same conditions, corresponding to a 24.33% increase in a 10 mm plate-spacing environment. The gripping module is integrated into the modular framework to extend the motion primitives of the soft robot to include anchoring functionality. The results indicate that the corrugated structure effectively suppresses the spindle effect and improves contact effectiveness under compression. These findings demonstrate that structural regulation of thin-film pneumatic actuators provides a feasible strategy for enhancing anchoring performance and locomotion capability of soft robots in confined pipeline environments.

Non-contact ultrasonic three-dimensional (3D) printing has emerged as a promising alternative to conventional energy-curing manufacturing techniques. However, an insufficient understanding of its underlying curing mechanisms still limits the precise regulation of solidification behavior and stable structural forming. In this context, this work develops a customized ultrasonic printing platform to investigate the thermoacoustic curing behavior of a modified PDMS-based material system. A multiphysics numerical model is established to characterize the focal acoustic pressure, concentrated energy distribution, and transient temperature evolution during printing. Simulated and experimental results collectively indicate that solidification behavior is governed by the balance between localized acoustic energy confinement and thermal diffusion. Systematic experiments are further conducted to quantify the effects of driving power, scanning speed, and line spacing on forming quality. The optimized parameter combination (17.5 W driving power, 0.4 mm/s scanning speed, and 0.2–0.25 mm line spacing) enables stable single-track morphology and favorable interlayer bonding. Additionally, reciprocating scanning trajectories are found to promote localized thermal accumulation, which may introduce dimensional deviations in printed structures. This study provides insights into ultrasonic thermoacoustic curing behavior and offers feasible process guidance for ultrasonic additive manufacturing under the specific material and experimental configurations adopted in this work.