Evolving an Aircraft Using a Parametric Design System

Jonathan Byrne

Natural Computing Research and Applications Group

University College Dublin

Ireland

The Importance of Mapping

Direct Mapping (Voxels)

Buildable Objects by Pollack and Funes (1999)

Issues with Direct Mappings

  • Shape not smooth or contains small holes
  • Scales poorly
  • Parents being valid doesn't guarantee valid children

Qualities of a Good Mapping:

  • Generates valid designs
  • High locality
  • Hierarchy, modularity and regularity

Parametric Design

  • Rapid prototyping technique
  • Define the relationships between components
  • Originally in Sketchpad

Why Parametric?

  • Adoption in Aeronautics and Architecture
  • Powerful applications in 3D printing
  • Programmers get it for free
  • Generates valid designs
  • Easy to evolve

Grasshopper

Turning Torso (Calatrava)

Messe Halle (Herzog & De Meuron)

Messe Halle (Herzog & De Meuron)

Rolex Learning Center (SANAA)

Open-Vehicle Sketch Pad (openVSP)



link

OpenVSP Hangar

OpenFOAM

  • Field operations and manipulation
  • Industrial Standard
  • Built on openMPI

OpenFOAM Toolbox

  • Meshing utilities
  • Incompressible (hydrodynamic) solvers
  • Transonic solvers
  • Heat transfer
  • Electromagnetic solvers
  • Financial solvers

SIMPLE Algorithm

  • Semi-implicit method for pressure linked equations
  • Iterative Navier-Stokes solver
  • Initial state set using inviscid solver

Aircraft Optimisation

Airfoil Representation

Wing Representation

Best Lift Maximisation

Best Drag Minimisation

Multi-Objective Optimisation

  • Conflicting design objectives
  • Lift versus drag of a wing
  • No perfect solution

Initial Generation

Evolving the Pareto Front

Final Generation

Blended Wing Body Optimisation

Pareto Front for BWB

Optimised Blended Wing Body Designs

Cessna 182 Optimisation

Final Pareto Front

Optimised Cessna 182 Designs

MIG 21 Optimisation

Final Pareto Front

Optimised MIG 21 Designs:

Conclusions

  • Parametric representations are easily optimised
  • Designer allowed to specify the search space
  • EAs capable of actively suggesting design improvements
  • OpenFOAM is a toolbox of fitness functions