Inverse design of bistable composite laminates with switching tunneling method for global optimization

Area of Science:

• Materials Science
• Mechanical Engineering
• Computational Design

Background:

• Bistability in composite laminates allows for adaptive designs with tunable deflections.
• Pre-strains during polymer matrix processing induce bistability, enabling reconfiguration between two stable shapes.
• Designing these bistable laminates is complex due to their nonlinear behavior.

Purpose of the Study:

• To propose a novel computational method for designing bistable composite laminates.
• To overcome the challenges posed by the highly nonlinear behavior of these materials.
• To enable inverse design for variable pre-strain fields and achieve complex curvatures.

Main Methods:

• Introduction of the Switching Tunneling Method (STM).
• STM alternates between gradient-based local minimization and tunneling search phases.
• Objective expression switching is used to enhance numerical conditioning.

Main Results:

• The STM demonstrates high effectiveness compared to existing optimizers.
• Achieved a 99% success rate in finding all energy minima for general composite layups.
• Enabled inverse design of variable pre-strain fields for bioinspired positive Gaussian curvatures.

Conclusions:

• The STM is a highly effective method for designing bistable composite laminates.
• The method facilitates the creation of complex curvatures not possible with conventional techniques.
• Finite element analysis and 3D printed samples validated the optimal designs.