Fabio Filippini, vice president design, Pininfarina, commented: “Sergio’s values of elegance, purity and innovation are in our DNA.”
“They are an important part of who we are and what make the Pininfarina touch so unique. This concept car is both an expression of our history and our vision for the future. It embodies the very principles Sergio embraced throughout his career.”
“We wanted to take Sergio’s original thinking of over 30 years ago and create a modern version of his ideas with a very exclusive and exciting design.”
The Sergio Concept was developed in just a few months and to meet the tight deadline Pininfarina used a combination of digital tools and packages provided by partner Dassault Systèmes through the 3DEXPERIENCE platform.
For the early concept phase designers used CATIA for Creative Designers, a solution that mixes polygonal / SDS modeling with traditional CAD surfacing tools (ICEM Surf) to quickly create, assess and modify different designs.
Marco Capolicchio, responsible for surface modeling, explains: “We adopted a multi-phased approach in which we first created preliminary shapes with CATIA Imagine & Shape and then visualized each one with the Live Rendering application. The ability to experience each design variation in 3D in a realistic virtual environment was very much appreciated and helped us to rapidly converge on the perfect design for the Sergio Car.”
“With Imagine & Shape, we transformed the car’s shape into a precise 3D geometric model using subdivision surfaces and created a mesh that our designers were able to easily deform and reshape at will.”
“In the second phase, we enhanced the technical content of the model by generating precise Class A surfaces, complete with manufacturing specifications, using the 3DEXPERIENCE surface modeling application ICEM.”
With CATIA for Creative Designers, all design and engineering information is available in one unique model and accessible to the community of project stakeholders.
“Our designers’ styling features, including textures and colors, were combined with the technical features developed by Pininfarina engineers. Everyone saw what his colleagues were doing, which facilitated the exchange of ideas, eliminated the frustration of time-consuming redesign work and accelerated the decision-making process,” Luca Margonari, team leader CAS modeler, said.
Changes in the body with which the Pininfarina Style Centre has transformed the original car. A Ferrari 458 Spider, into a barchetta were supported by calculations and tests in the Grugliasco wind tunnel to optimise aerodynamic performance. In particular, a totally new body was produced, full carbon, saving about 10% in weight compared to the original body in aluminium, all to the benefit of acceleration and pick-up.
Compared to the original car, 21” light alloy one-stud wheels were included, with a specific design, and a hub version derived from the 458 Challenge; new Led taillights, new specific headlamps inserted into the bumper; specific small doors, window-less and opening upward by 45 degrees; new dash top; modified seats, with new fixed head restraints, disconnected from the seat. The roof, windscreen and rear bench seat were removed.
The aerodynamics have made it possible to achieve interesting results, starting with the creation of a virtual windscreen.
The elimination of the windscreen would, in fact, involve a flow of air at increasing pressure as the car’s speed increases on the heads of the driver and passenger.
The engineers and designers at Pininfarina have therefore designed, built and tested an airfoil placed in a recess on the front bonnet, which produces a double deflection of the air flow entering the passenger compartment. The first deviation is from the wing itself, the second from the air that accelerates in the channel created between the airfoil and the corresponding shape of the recess in the trunk.
The result is that, thanks to the virtual windscreen, the air passes above the heads of the driver and the passenger, greatly increasing comfort. This aerodynamic effect also contributes to increase the down force on the car’s front axle. The virtual windscreen is effective at speeds as low as 50 kph.
The loss of aerodynamic load on the front axle, due to the elimination of the windscreen, has been recovered from a wing inserted in the front bumper. The shape and dimensions of the wing are calculated so as to give the required load at the various speeds and, at the same time, allow correct flow of air to the radiators of the cooling system, set centrally at the front.
To improve the protection of the occupants a roll-bar with a fixed spoiler increases the down force on the rear axle. The attention to detail goes so far as the central rear-view mirror, whose form has been aerodynamically optimized to link up with the air flow of the virtual windscreen. The engine’s air intake is channelled from the air inlets in the two sides. The air vents at the base of the roll-bar convey the cooling air to the oil coolers.
Overall, the Sergio offers real sports performance, with a shell of torsion stiffness which exceeds that of the original spider, thanks to the reduction in the size of the doors, and the reduction of the total mass of about 150 kg compared to the spider. This allows good handling and a further improvement of acceleration, estimated at below 3.4 seconds for 0-100 kph, at the top of its class.