The project of the first Polish super car, Arrinera Hussarya, from its very beginning aroused strong emotions and hopes that the Polish automotive industry could come back to its past glory. The production of functioning prototypes that at the same time had to achieve the level of a sports car required incredible precision and durability. (The name Hussarya refers to the Polish cavalry from the 17th century)
Unlike most contemporary Polish automotive projects, Arrinera Hussarya is built from the ground up. All parts of the car body, engine and interior, despite the fact that they often use proven technologies, are redesigned to not only meet all the requirements but to also represent the aesthetics worthy of a super car. Designing and building its first super car is not only an engineering but also a financial challenge. 3D technologies provided both cost savings and the required precision during the data acquisition, prototyping and production adjustments. Arrinera was able to significantly accelerate the prototyping process and reduce the time required for production.
By implementing a professional SMARTTECH 3D scanner, the engineers working on the super car gained the ability to quickly obtain comprehensive information about the geometry of the car parts.
A 3D scanner MICRON3D green with 10 megapixel detector was used for accurate measurement. The technology based on the green LED light allows the measurements to achieve 30% better results than when using 3D scanners with white light. With a field of view of 800 x 600 mm, the 3D scanner obtains a point cloud representing the scanned shape with 0,084 mm accuracy.
The measurement performed by a SMARTTECH 3D scanner is based on the projection of patterns on the measured surface. The patterns deform depending on the curvature and are recorded by a detector integrated in the measuring head. The device measures only the surfaces that are visible to the detector. In order to obtain a comprehensive information about the geometry from every angle the object needs to be scanned using a rotary stage. The load capacity of the rotary stage is over 300 kg while its diameter is 50 cm, which is sufficient to perform complete measurement of most car parts.
MICRON3D green is metrologically certified in accordance with the German VDI/VDE 2634 standard providing Arrinera confidence that the measurement error does not exceed the values given in the device’s accuracy certificate.
The image from the detector is converted into a point cloud using a special software algorithm. Each of the points contains information about the geometry described in the X, Y, Z coordinates. Depending on the resolution, the point cloud from a single measurement can consist of 5 or 10 million points for a resolution of 5 or 10 megapixels, respectively. The number of megapixels affects the extent of detail obtained from a given object. In Arrinera’s case, a 3D scanner with a 10 megapixel detector was used since there was a need to accurately reproduce the edges of the measured object.
The use of the MICRON3D green in the workshop is possible since the housing is manufactured from carbon fiber. The protection of the precious interior is provided by a F7 class filter. The durable housing guarantees not only reliability but also stability and high quality of measurements. In addition, the internal shock absorber system suppresses vibrations that may affect the accuracy of the results.
One of the scanning applications was gathering geometric data of the existing vehicle sills collected directly from the physical prototype. The Hussarya super car stood on a platform and access to the sill was hindered by the car door. Because the sill’s dimensions were much larger than the field of view of the 3D scanner it was necessary to use a very useful scanning function with positioning markers.
The measurement method using markers relies on attaching special positioning markers on the scanned object. The software SMARTTECH3Dmeasure that operates the 3D scanner finds five common positioning markers between two individual measurements and then aligns them. The 3D scanner operator has a full view of his work and can easily add scans of the remaining parts of the sill.
The result of 3D scanning with positioning markers is a preliminary aligned cloud point. Further post-processing in SMARTTECH3D software is done similarly every time because of its intuitive design and ability to automate individual operations. In this case it was also necessary to create a reference CAD model in Geomagic Design X, used by Arrinera.
Having a CAD model of a given element enables the use of the 3D printing technology for rapid prototyping. Arrinera chose the solution from a Poznan-based company OMNI3D, whose flagship product Factory 2.0 Production System creates large format 3D prints in FFF (fused filament fabrication) technology.
For more information: www.smarttech3d.com