The previous page shows four streamlined designs. The top-left design is an 'aerodynamic' front of a train. The top-right design is an 'aerodynamic' car shape, evolved around a fixed chassis. The bottom two designs are 'hydrodynamic' designs of boat hulls. All designs were defined to be symmetrical about the plane z=0 and were evolved from an initial population of random shapes.
The desired functions of these designs were defined by three reusable 'evaluation modules'. These specified that the designs should be a certain size, should be unfragmented (i.e., no part should be unconnected and 'float free' of a design), and that a number of specified forces acting on them should be generated when particles flow past them. To evaluate this, a naive particle flow simulator was used to fire particles at designs (simulating the flow of air or water), and calculate the forces generated when they bounced off the designs.
Despite the limitations of the solid-object representation used (only able to approximate curves), the streamlined designs all show sensible features. The train design (top-left) directs 'air' efficiently around the design, while still generating an overall down-force, as required. The car design (top-right) resembles a people-carrier or transit-van, using a sloping front to minimise wind-resistance while generating the required down-force. (Interestingly, it was evolved around the chassis of a common saloon car, but the computer preferred this type of design solution.) The first boat hull (bottom-left) resembles that of a traditional small boat or ship, with a pointed and sloping bow to direct 'water' to either side of the hull and to generate the desired up-force. The second evolved hull (bottom-right) resembles a twin-hulled catamaran, directing water underneath the hull to allow it to cut through water cleanly and generate the desired up-force. (The computer seemed to prefer the catamaran design to the single-hull design.)