Magnetic Soft Helical Manipulators with Local Dipole Interactions for Flexibility and Forces

Area of Science:

• Robotics
• Materials Science
• Biomedical Engineering

Background:

• Magnetic continuum manipulators (MCMs) are remotely actuated robots used in confined spaces.
• Existing MCM designs face a trade-off between magnetic moment and flexibility, limiting their application in complex environments like medical procedures.
• Flexible magnetic structures are crucial for navigating tortuous paths in medical applications.

Purpose of the Study:

• To propose a new MCM design framework that overcomes the limitations of existing cylindrical designs.
• To enable increased diameter in MCMs without sacrificing flexibility or magnetic moment.
• To improve the maneuverability and applicability of MCMs in confined medical workspaces.

Main Methods:

• Developed a novel MCM design framework utilizing magnetic soft composite helices as bending regions.
• Incorporated permanent ring magnets separated by specific spacing to leverage local dipole interactions.
• Investigated the impact of local dipole interactions on bending stiffness and angular deflection.
• Fabricated and tested a multisegment MCM in an abdominal aorta phantom.

Main Results:

• The proposed design allows for increased diameter without compromising flexibility and magnetic moment.
• Local dipole interactions between permanent magnets reduced bending stiffness, increasing angular deflection by 31% compared to designs without these interactions.
• Demonstrated successful fabrication and maneuverability of a multisegment MCM.

Conclusions:

• The new MCM design framework offers enhanced performance for navigating complex paths.
• The design shows significant potential for medical applications, including procedures within the abdominal aorta.
• This advancement facilitates the use of MCMs for tasks such as passing guidewires and contrast dye.