Simultaneous optimisation of earwig hindwings for flight and folding

Area of Science:

• Insect flight mechanics
• Bio-inspired engineering
• Structural mechanics

Background:

• Earwig wings are complex, highly foldable structures lacking intrinsic muscles.
• Their flight behavior and dynamic shape changes remain poorly understood.
• Significant structural challenges exist in controlling deformations and preventing wing collapse during flight.

Purpose of the Study:

• To investigate the unknown behavior and shape changes of earwig wings during flight.
• To understand how these wings manage deformations and avoid collapse.
• To reveal adaptations in structure and material contributing to passive wing control.

Main Methods:

• Detailed microscopy studies to analyze wing structure and material properties.
• High-speed video recordings to capture wing deformations during flight.
• Analysis of flexion line dynamics and its role in wing stability.

Main Results:

• Earwig wings exhibit distinct structural areas with varying vein stiffness and material properties.
• High-speed recordings revealed significant wing deformations and stress points during flight.
• A dynamic concave flexion line was observed, which actively blocks critical folding lines to prevent wing collapse.

Conclusions:

• Earwig wings employ a passive control mechanism involving a dynamic flexion line to maintain structural integrity during flight.
• Adaptations in wing structure and material contribute to this passive stability.
• These findings provide valuable insights into passive control strategies for highly foldable structures.