In recent years, the rising incidence of gastrointestinal (GI) cancer has triggered an urgent need for effective early intervention strategies. Traditional endoscopic techniques often cause patient discomfort, and it is difficult to navigate deep regions of complex organ structures. This work proposes a kind of bio-inspired magnetic soft robot (BMSR) to address these challenges. The design of the BMSRs is inspired by the rolling motion of the golden wheel spider. Two six-degree-of-freedom (6-DOF) robotic arms are used, where one arm is responsible for real-time manipulation of the BMSRs, and the other is dedicated to monitoring their status. Under the actuation of an external rotating magnetic field, the BMSRs can flexibly climb on inclined surfaces at any angle, involving the inverted surface. Through the powerful output force, the BMSRs can overcome the mobility barrier induced by different human organs, including mucus, folds, and height differences of up to 8 cm. Such an exceptional mobility enables the BMSRs to deliver drugs in the targeted complex GI environment. Moreover, in combination with an endoscope, it provides real-time visual feedback for precise navigation. In vitro animal experiments validate the feasibility of BMSRs, paving a way for their usage in minimally invasive GI treatment. This work advances the potential applications of magnetic soft robots in the biomedical field.

In modern medical treatment, ultrasound scanning provides a radiation-free medical imaging method for the diagnosis of soft tissues via skin contact. However, the exerted contact force heavily relies on the skill and experience of the operator, which poses great inspection instability. This article reports on a robotic ultrasound scanning system with a constant-force end-effector. Its uniqueness is the introduction of a hybrid active–passive force control approach to maintaining a constant contact force between the ultrasound probe and the continually changing surface. In particular, the passive constant-force mechanism provides strong buffering to the force variation. The active force control system improves flexibility and provides long-stroke positioning. Experimental tests on both silicone models and human volunteers demonstrate the capability of the proposed robotic ultrasound scanning system for obtaining qualified ultrasound images with high repeatability. Moreover, the ease of operation of the robotic US scanning system is verified. This work provides a promising method to assist doctors in conducting better and cushier ultrasound scanning imaging.

Magnetic soft robots have recently become a promising technology that has been applied to minimally invasive cardiovascular surgery. This paper presents the analytical modeling of a novel multi-section magnetic soft robot (MS-MSR) with multi-curvature bending, which is maneuvered by an associated collaborative multirobot navigation system (CMNS) with magnetic actuation and ultrasound guidance targeted for intravascular intervention. The kinematic and dynamic analysis of the MS-MSR’s telescopic motion is performed using the optimized Cosserat rod model by considering the effect of an external heterogeneous magnetic field, which is generated by a mobile magnetic actuation manipulator to adapt to complex steering scenarios. Meanwhile, an extracorporeal mobile ultrasound navigation manipulator is exploited to track the magnetic soft robot’s distal tip motion to realize a closed-loop control. We also conduct a quadratic programming-based optimization scheme to synchronize the multi-objective task-space motion of CMNS with null-space projection. It allows the formulation of a comprehensive controller with motion priority for multirobot collaboration. Experimental results demonstrate that the proposed magnetic soft robot can be successfully navigated within the multi-bifurcation intravascular environment with a shape modeling error 3.62 ± 1.28° and a tip error of 1.08 ± 0.45 mm under the actuation of a CMNS through in vitro ultrasound-guided vasculature interventional tests.