Independent and Hybrid Magnetic Manipulation for Full Body Controlled Soft Continuum Robots

Fully soft continuum magnetic (FSCMs) microrobots with highly deformable structures have emerged as a potential solution to robotically controlled endovascular interventions. The microrobot's structure is made of magneto-responsive material, which offers full body control under a magnetic field instead of limited tip deformation. The shape control for these microrobots enables steering in complex paths with limited contact with the environment. We studied full body control under fields generated using up to two robotically controlled permanent magnets and in combination with an electromagnetic system. The effect of different parameters, such as the number of permanent magnets, position of the permanent magnets and intensity and direction of the electromagnetic field, on the robot's shape has been experimentally investigated. A mathematical model to predict tip deformation angle (TDA) was introduced and verified experimentally (root mean square error (RMSE) 6.5). Ten different characteristic body shapes were identified based on the curvature of the soft robot. Based on the obtained data, a proof-of-concept demo is presented for the full body controlled soft robots. The accuracy of steering soft robots on a continuous path with all three magnetic control strategies was investigated. The results show that the proposed method effectively enables shape forming and minimizes contact with the surrounding environment (the average distance to the centerline was 1.24 mm). The proposed approach hold promises to elevate endovascular interventions towards the least invasive surgery.