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Updated: Sep 10, 2025
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Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
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A Magnetically Transformable Twisting Millirobot for Cargo Delivery at Low Reynolds Number
Moonkwang Jeong1,2, Jiyuan Tian2, Meng Zhang2
1Cyber Valley group - Biomedical Microsystems Institute of Physical Chemistry University of Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany.
Summary
This study introduces TwistBot, a flexible millirobot that transforms into a helical shape using magnetic fields for propulsion in fluids. This innovation simplifies the fabrication of micro-robots and enables targeted cargo delivery.
Area of Science:
- Robotics
- Biomimetics
- Materials Science
Background:
- Bacteria flagella inspire helical micro-robots for fluid propulsion at low Reynolds numbers.
- Fabricating rigid helical microstructures typically requires complex 3D micro-/nanofabrication techniques.
- Current methods face challenges in producing 3D helical structures without specialized machinery.
Purpose of the Study:
- To introduce a novel magnetically transformable millirobot, TwistBot, with a flexible body.
- To enable propulsion in viscous fluids through shape transformation from a flat ribbon to a helical form.
- To demonstrate a simplified fabrication approach for helical micro-robots.
Main Methods:
- Developing a flexible millirobot (TwistBot) capable of shape transformation.
- Applying an external magnetic field to induce twisting and helical formation.
- Utilizing numerical simulation to model the robot's twisting behavior.
- Optimizing the robot's geometry to maximize the twist angle.
Main Results:
- TwistBot successfully transforms from a flat ribbon to a helical shape under a magnetic field.
- The helical transformation enables propulsion in viscous fluids.
- Numerical simulations and geometric optimization were used to enhance the twist angle.
- The robot demonstrated capability for navigating narrow lumens and delivering cargo.
Conclusions:
- The TwistBot offers a new, simplified method for fabricating transformable micro-robots.
- Flexible helical robots can be propelled and utilized for targeted cargo delivery.
- This concept opens avenues for designing soft, transformable minirobots for biomedical and other applications.
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