Helical micro-swimmer: hierarchical tail design and propulsive motility

Area of Science:

• Robotics and Micro-engineering
• Biomedical Engineering
• Fluid Dynamics

Background:

• Helical micro-swimmers are crucial for lab-on-a-chip and minimally invasive medicine.
• Previous research focused on actuation principles, neglecting structural design for propulsion enhancement.
• Optimizing structural design is key for agile locomotion in micro-swimmers.

Purpose of the Study:

• To present a novel hierarchical helical swimming robot design.
• To enhance the motility and performance of helix-based micro-swimmers.
• To investigate the impact of hierarchical structures on propulsion, stability, and velocity control.

Main Methods:

• Developed a numerical model based on resistive force theory for mechanics analysis.
• Analyzed mechanical properties considering various geometric parameters.
• Compared the motion performance of hierarchical and conventional helical structures in low Reynolds number regimes.

Main Results:

• The hierarchical helical design significantly enhances micro-swimmer motility compared to conventional structures.
• Numerical models accurately predict mechanical properties and performance.
• Hierarchical swimmers demonstrate improved stability, resilience, and controllable forward velocity.

Conclusions:

• The proposed hierarchical helical design offers a reliable strategy for improving micro-swimmer performance.
• This design provides enhanced propulsion, stability, and agility for micro-scale locomotion.
• The hierarchical helical robot presents opportunities for advanced medical robots and bio-integrated electronics.