Pininfarina Sergio Concept | The Design Process

On May 23, 2013 Pininfarina and Dassault Systèmes held a presentation of the Sergio Concept and its design process.We had the opportunity not only to hear the story behind the show car presented at the last Geneva Show, but also to visit the company’s Museum and watch a live demonstration of the digital technologies used during the development of the concept.

The challenge
Soon after long-time president Sergio Pininfarina passed away on July 2, Pininfarina’s management decided to pay him a tribute by creating an exclusive automobile that would incorporate the design studio’s trademark values in their purest form.When the project started in September 2012, it was evident that this new concept had to be ready by early March for the Geneva Motor Show, which is traditionally the most important event for European car design studios.
This resulted in a very tough challenge: the show car, to be named after Sergio himself, had to be fully developed in just six months – an even tougher task given the symbolic value of the project.

To face this challenge Pininfarina decided to adopt an innovative approach, making extensive use of the new tools provided by Dassault Systèmes’ 3DExperience platform, a solution that integrates concept design tools (CATIA for Creative Designers), surfacing tools (ICEM Surf), engineering solutions (CATIA) and advanced visualization modules into a single working environment.

Design ConceptTo be true to Pininfarina’s long standing values, the design studio decided to built a two-seater barchetta, which as Pininfarina design director Fabio Filippini explains “is the extreme archetype of sportscars.”

Another important element was the possibility to create a car in partnership with Ferrari, a prestigious name that has been associated with Pininfarina for decades.

Once Ferrari President Luca di Montezemolo had given his full support to the project, the design brief was further developed.Since from the very beginning the Sergio Concept was conceived as a feasible sportscar that could be easily be produced in a limited series, rather than an experimental, extreme show-car.

The technical basis was provided by the Ferrari 458 Spider platform, used for both the frame and the complete chassis/powertrain.The main design inspiration came from the Ferrari cars of the 60′s and the 70′s, and in particular from the 1965 Ferrari Dino Berlinetta, the first car fully designed by Sergio Pininfarina and the first Ferrari powered by a rear-mounted engine.


At the end of the first 2D conceptual phase, during which several design directions were explored through traditional drawings, a particular sketch was selected (above picture) as a starting point for the development of the car.

3D Concept Modeling
The most distinctive element in the design process of the Sergio is the adoption of new 3D concept modeling techniques, provided by technical partner Dassault Systèmes through the 3DExperience integrated platform.
3D Sketching

In the first design stages, when the 2D sketches are being transferred to 3D, the platform offers a one-of-its-kind 3D sketching system, called CATIA Natural Sketch, which allows to easily draw curves like inside a digital sketching program, but in three dimensions, and to transform them into editable curves that can be used as references in the modeling process.

3D Modeling
Traditionally, automotive design studios adopt NURBS-based 3D modelers, which allow a complete control over the mathematical representation of the geometry and the resulting surface quality, which is necessary for the subsequent manufacturing requirements.

However, in the first conceptual design phase the benefits of this level of precision are largely diminished by the drawbacks in terms of development times.

This fact has recently brought several car companies to explore different 3D modeling techniques, in a way less “accurate”, but much faster and flexible in terms of creative freedom.

For this reason design studios are starting to adopt polygonal modelers, traditionally employed in entertainment industries like movies and videogames.

Using these tools, the car body surfaces are represented by a single mesh of polygons rather than by a layout of NURBS patches joined together.

This enables designers to change the shapes by simply pushing and pulling vertices, edges and polygons, in a way which is very close to physical clay modeling.

Thanks to the availability of efficient smoothing algorithms – mainly based on the Catmull-Clark subdivision surfaces (SDS) method – the meshes are transformed into smooth, curvature continuous geometries, with a quality which is largely sufficient for the first concept design stage.

However these polygonal modeling techniques do have some specific limits – which we will cover in an upcoming series of technical articles – and until now the modeling process was almost completely separated from the parallel engineering development and the modeling of the final Class A surfaces needed for manufacturing.

With the 3DExperience platform, Dassault Systèmes has for the first time integrated the different modeling techniques into a single working environment, which in the case of the Sergio Concept has allowed designers to explore, review, modify and validate the design in a very short timeline

Another benefit of the integrated platform was the direct connection between designers and engineers, who were able to easily communicate along the entire design process thanks to the centralized data storage and tools such as screen sharing and remote control.

From the concept to the final prototype
Once the conceptual modeling phase was completed, the car was re-modeled using Icem Surf for achieving the final high quality surfaces.The resulting CAD data were used to mill a full-scale physical model that was used to review and fine-tune the design.

After these minor modifications were completed inside the 3D surfacing modeler, the final tooling was signed off and in December 2012 the work switched to the actual prototype, which was completed in time for its official debut at the 2013 Geneva Motor Show.Right: the Sergio Concept revealed by Fabio Filippini, Pininfarina design director, and Xavier Melkonian, Dassault Systèmes Director, CATIA Design Offer

by (Car Body Design, Pininfarina, Dassault Systèmes)