Configuration Optimization Strategy of Magnetic Soft Robot for Robot-Assisted Intervention

Magnetic soft robots (MSRs) are promising tools for precise intravascular interventions due to their flexibility and magnetic actuation capability, yet existing designs face fundamental trade-offs: magnetic continuum robots offer uniform deformation but suffer from weak magnetic responsiveness, while magnet-tip robots provide strong actuation but lack flexibility and workspace. Previous optimization strategies have largely treated geometry, material distribution, and magnetic configuration separately, leaving their coupled effects insufficiently understood. Here, we introduce a comprehensive theoretical model that unifies elastic, magnetic, gravitational, and external forces to analyze the MSR’s dynamic response and energy distribution. Guided by this model, we design a model-guided MSR with tailored magnetic distribution and structural configuration, achieving a normalized forward workspace of 0.28, which is nearly eight times larger than that of conventional continuum designs and more than twenty-seven times greater than typical magnet-tip robots, thereby establishing a new state of the art among 31 existing designs. Building upon this advance, we develop a Bio-Inspired Teleoperated Magnetic Navigation System (BITMNS) that integrates the model-guided MSR with a robotic magnetic manipulator and delivery device. In-vivo rabbit experiments demonstrate precise navigation through tortuous vascular pathways to the renal artery, while remote operation eliminates operator radiation exposure (238 mGy → 0) and force analyses confirm robustness under loads up to 9.5 times the safety threshold. Collectively, these advances expand the navigable vascular workspace, eliminate operator radiation exposure, and establish a safety margin nearly one order of magnitude above clinical thresholds, thereby demonstrating a concrete pathway toward safer and more effective endovascular interventions.