Short answer

Designers can explore the use of composite materials in non-traditional, irregular shell geometries to achieve bistable behavior for adaptive structural applications.

Field: Final Production
Source: 56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference (2015)
Method: Computational modelling and simulation
Evidence: Strong effect

Thin composite shells with non-standard shapes can exhibit bistability, allowing for large shape changes while retaining structural integrity, by leveraging kinematic nonlinearities. This final production research insight is drawn from a 2015 study published in 56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference. Using Computational modelling and simulation, researchers explored how this design variable affects real-world outcomes. The key design takeaway: Designers can explore the use of composite materials in non-traditional, irregular shell geometries to achieve bistable behavior for adaptive structural applications.

Study

Final ProductionHigh ImpactStrong effect

Irregular Composite Shells Achieve Bistability Through Kinematic Nonlinearity

Thin composite shells with non-standard shapes can exhibit bistability, allowing for large shape changes while retaining structural integrity, by leveraging kinematic nonlinearities.

56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference · 2015

Key Findings

01An accurate and computationally efficient energy-based model can predict the multistability of thin shallow composite shells with irregular domains.
02The use of blending functions effectively maps irregular physical domains to regular computational domains for DQM analysis.
03Accurate evaluation of membrane energy is critical for correctly identifying bifurcation points and stable states.

Application

Design takeaway

Designers can explore the use of composite materials in non-traditional, irregular shell geometries to achieve bistable behavior for adaptive structural applications.

How to apply

When designing deployable structures or components requiring shape-changing capabilities, consider the use of composite shells with irregular planforms and analyze their potential for bistability using energy-based computational models.

Project actions

01When designing a product that needs to change shape, think about how the material and its form can work together to allow this transformation.
02Consider using composite materials for their strength-to-weight ratio and potential for complex forms.

Method & Evidence

AimTo investigate the multistability of thin shallow composite shells with irregular planforms and develop an accurate, computationally efficient energy-based model for predicting their behavior.

MethodComputational modelling and simulation

ProcedureAn energy-based model was developed, decoupling membrane and bending strain energy components. Transverse displacements were approximated using Legendre polynomials, and the membrane problem was solved using the Differential Quadrature Method (DQM) on a transformed regular domain via blending functions. Stable shapes were identified by minimizing the total potential energy with respect to curvature.

ContextAerospace structures, adaptive materials, structural engineering

Variables

IVShape of the composite shell (regular vs. irregular planform), material properties (composite layup), shell geometry (shallow vs. deep).

DVBistability (presence and nature of stable equilibrium states), load-bearing capacity, energy required for shape change.

CVShell thickness, material strain limits, type of loading (transverse displacement).

Strengths & Limitations

Strengths

+Develops a computationally efficient model for complex geometries.
+Addresses a gap in research concerning irregular planforms for multistable shells.

Limitations

The computational models used may require significant processing power and expertise to implement accurately. Experimental validation of the predicted bistable states would be necessary for real-world applications.

Reliability & validity

The reliability of the computational model depends on the accuracy of the DQM method and the blending functions. Validity would be assessed by comparing simulation results with experimental data from physical prototypes.

Think critically

How might the computational complexity of modeling irregular morphing structures limit their practical application in rapid prototyping or on-demand manufacturing?

Design Principles

"Kinematic nonlinearity in composite shells can be exploited to achieve multistable behavior, enabling large shape changes while maintaining structural integrity."

This research opens avenues for designing adaptive structures that can change form in response to external stimuli or operational needs. Understanding how to achieve bistability in irregular geometries is crucial for developing advanced deployable structures, morphing aircraft wings, or responsive architectural elements.

What This Means for Your Design

Imagine a flat sheet that can fold into a dome, and then fold back flat again, all while staying strong. This research shows how to design such 'morphing' structures using special composite materials, even if the shapes aren't simple circles or squares.

How to use in your project

1.This research can inform the material selection and structural design of a morphing product, particularly if bistability is a desired feature.

Add to My Project

Quick Cite

Paragraph starter

The study by Lamacchia et al. (2015) on morphing composite shells with irregular planforms highlights the potential for kinematic nonlinearity to achieve bistability. This principle can be applied to design adaptive structures that undergo significant shape changes while maintaining load-bearing capacity, offering a valuable approach for innovative product development.

Source

56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference

Morphing structures: non-linear composite shells with irregular planforms

journal · 2015

View source

Questions About This Research

What does the research say about irregular composite shells achieve bistability through kinematic nonlinearity?: Designers can explore the use of composite materials in non-traditional, irregular shell geometries to achieve bistable behavior for adaptive structural applications. Evidence: 56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference (2015).
Why does "Irregular Composite Shells Achieve Bistability Through Kinematic Nonlinearity" matter for design?: This research opens avenues for designing adaptive structures that can change form in response to external stimuli or operational needs. Understanding how to achieve bistability in irregular geometries is crucial for developing advanced deployable structures, morphing aircraft wings, or responsive architectural elements.
How can designers apply this research?: Designers can explore the use of composite materials in non-traditional, irregular shell geometries to achieve bistable behavior for adaptive structural applications.
What were the main findings?: An accurate and computationally efficient energy-based model can predict the multistability of thin shallow composite shells with irregular domains.. The use of blending functions effectively maps irregular physical domains to regular computational domains for DQM analysis.. Accurate evaluation of membrane energy is critical for correctly identifying bifurcation points and stable states.
What research method was used?: Computational modelling and simulation.
How strong is the evidence?: Evidence strength is rated Strong effect, based on a 2015 journal from 56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference.
What should I do differently in my next project?: When designing deployable structures or components requiring shape-changing capabilities, consider the use of composite shells with irregular planforms and analyze their potential for bistability using energy-based computational models.
What are the limitations?: The model is focused on thin, shallow shells; deeper or thicker shells may exhibit different behaviors. The accuracy of the DQM method is dependent on the chosen approximation functions and grid density.