When engineers at CATIA/DS wanted to show potential customers how they can prototype an automobile with 3D printing, they took the process to a new level! Showing off the capabilities of their Objet260 Connex Multi-material 3D Printer from Stratasys, a team led by Xavier Melkonian created “Project Bleu,” a 5-part car design study in physics, design and modeling.
An artistic rendering of the final car model, in blue.
The CATIA software division of Dassault Systèmes, specializing in CAD for 3D modeling, creates prototypes for many aerospace and automotive companies in worldwide. Laurent Igarza helped dream up the Project Bleu proof of concept experiment: “It was a challenge to our own R & D. We took a full team from sketching through 3D printing.”
“The primary goal of Project Bleu was to create our own in-house show car from scratch, demonstrating our latest modeling technologies from the CATIA design suite,” Igarza told Stratasys in an interview. Additionally, the project designs, resulting car models and the copyrights of Bleu fully belong to Dassault Systèmes, rather than its customers. Igarza plans to bring Project Bleu components with him to industry shows, such as Euromold, to discuss CAD design and the 3D printing process with potential clients.
The Objet260 Connex Multi-material 3D Printer from Stratasys was a valued “team member” of Project Bleu.
The Project Bleu car was a mission that lasted all of 2013. A team was assembled that included one creative designer, two concept modelers, two visualization experts, two class A surfaces modelers, and one mechanical modeler. Of tremendous importance was the incredibly precise Objet260 Connex Multi-material 3D Printer, which Igarza considered a valuable part of the team: “The very fine printer resolution (33 microns using 2 materials at the same time) allowed us to cross check & definitively validate the design on the 3D printed models compared with the previous realistic pictures we had just produced with CATIA Live Rendering application.”
As Igarza explained to us, the models of Project Bleu represent five distinct stages.
The first element for the design team was to get their feet wet with tiny cars. The cars were 3D printed at 5 cm in length. These models were intended to catch basic design flaws before further work was done. (Detailed miniature cars don’t present a challenge for the Objet Connex Multi-material 3D Printer series, however!)
The second stage of Project Bleu was proportion studies using models 3D printed at 10 cm. These models were made to ensure that the different design elements worked together in terms of volume and proportion. “We found out that small scale 3D printing was so complementary to any ‘scale 1’ reviews to validate design or reveal mistakes that we actually followed this process all along the ideation phase,” said Igarza.
A model 3D printed on the Objet260 Connex at 10 cm helps to validate the car’s design.
The middle stage of the project was an essential element of automotive and aerospace design – the speedform model. Speedform models are a crucial test for aerodynamics. Details such as wheels, mirrors and interiors are left off this kind of model which must stand up to testing in a wind tunnel.
These stripped-down speedform models, fresh from the Objet260 Connex Multi-material 3D Printer, are ready for aerodynamic testing.
After passing the speedform test, the refined Project Bleu car grew to 26 centimeters, stretching to match the capacity of the Objet260 Connex Multi-material 3D Printer build tray. Details such as mirrors and bumpers were included in the model at this stage.
The final stage of Project Bleu was printing the car as if it were a functional toy. In this stage, tweaks to the design changed the chassis to allow for wheel movement. This new chassis could quickly be modeled using CATIA Natural Shape application allowing its delivery right on time to grace the table at EuroMold 2013!
The undercarriage allows the Bleu car model’s wheels to move smoothly, as a toy car would.
For 3D printing different parts of the car on the Objet260 Connex Multi-material 3D Printer, the Project Bleu team used several kinds of PolyJet materials, including black rubber-like material (TangoBlackPlus) for the wheels, rigid opaque white (VeroWhitePlus) for the undercarriage and clear transparent (VeroClear) for the windows. These materials are readily combined to create other parts of the cars. “The rubber-like feel of the black rubber-like material (TangoBlackPlus) was a great simulator for real tires,” Igarza noted.
Multiple materials 3D printed simultaneously in one print job on the Objet260 Connex harmoniously join together to produce these realistic tires.
Even though Dassault Systèmes’ intent for Project Bleu was to stretch and demonstrate CATIA’s own engineering and design capabilities, plans are in the works to share the technical steps and STL files - Igarza’s team has posted a “work in progress” blog, webinars and STL files for home download. Check out this video that captures some pieces of the process, such as 3D CAD and 3D printing:
We’re going to be following Project Bleu closely to watch how design, engineering and multi-material 3D printing come together to make the Project Bleu car a model showpiece.