Abstract
Based on soft body structure and unique gait of bending and stretching, Soft Bionic Inchworm Robots (SBIRs) are used in pipeline inspection and terrain exploration. Many existing SBIRs rely on complex production mechanisms and are cable-driven, which hinders rapid production and smooth movement through complex environments, respectively. To address these challenges, this paper introduces a 3D-printed SBIR, featuring a 3D-printed body actuated by magnetic forces. We introduce the design and production process of the 3D-SBIR and analyze its motion gait. Subsequently, the material composition model and bending deformation model of the robot are developed based on the theory of hyper-elastic materials. The accuracy of the model is validated using simulation analysis and experimental testing of the robot. Meanwhile, we carry out a magnetic simulation analysis and discuss the factors influencing the size of the magnetic force. Finally, a series of experiments are conducted to prove the excellent locomotion capability of the robot. The 3D-SBIR demonstrates remarkable flexibility and multimodal movement capabilities. It can navigate through narrow curved passages with ease, passively overcome obstacles, climb steps up to 0.8 times its body height, and perform a seamless transition while moving across a horizontal plane onto a vertical plane. The 3D-SBIR proposed in this paper is characterized by rapid production, cable-free actuation, and multimodal motion capabilities, making it well suited for moving in unstructured environments.