Hybrid Magnetic Locomotion Method for Capsule Robots

Abstract

OBJECTIVE: Gastrointestinal (GI) capsule endoscopes typically rely on a single mode of locomotion, which limits their efficiency within the complex GI tract. To address this issue, this paper presents a hybrid magnetic locomotion method for capsule robots. METHODS: The proposed method features two distinct locomotion modes: inchworm-like and spiral. These two locomotion modes can be independently controlled to adapt to different sections of the GI tract. By integrating a magnetic torsion spring (MTS), the capsule robot achieves hybrid locomotion under the control of an external magnetic field. The MTS exhibits a Dual-Mode Magnetic Response under varying magnetic field strengths. Different control methods have been developed based on the Dual-Mode Magnetic Response of the MTS. RESULTS: A prototype has been fabricated and integrated with a commercial capsule endoscope, which has a diameter of 18 mm and a length of 31.3 mm. In vitro and phantom experiments validated the effectiveness of the proposed design and driving methods. CONCLUSION: By employing two independently controlled locomotion modes, the hybrid magnetic locomotion method efficiently drove the capsule endoscope through various GI environments. SIGNIFICANCE: The hybrid magnetic locomotion method significantly improves the adaptability and efficiency of capsule robots within the GI tract, thereby reducing examination times and enhancing the overall effectiveness of GI endoscopic procedures.