A monocoque is a vehicle structure where the chassis is integral to the body. Every year, the students of the Duale Hochschule Baden-Württemberg (Baden-Wurttemberg Cooperative State University) take part in the “Student Formula” race with a custom-built racing car. Universities from all over Europe participate and present the racing cars they developed and built specifically for this event. They are evaluated by a jury that takes into consideration categories such as speed, technology, safety, marketing and design. The competition gives students a direct application for engineering solutions that can involve everything from mechanical engineering to aerodynamics and metrology.
The students of the DHBW Engineering Stuttgart eV selected to scan this year’s monocoque using SHINING 3D’s handheld laser 3D scanner, the FreeScan X5. This metrology laser scanner is ideal for scanning large objects with the utmost accuracy (up to 0.03 mm) and precision (with volumetric precision up to 0.02 mm + 0.08 mm/m). Using its intersecting lasers, the system is able to scan objects that more common structured light scanners have a hard time with, including darker/black objects and reflective surfaces, like the composite monocoque built by the DHBW students.
The output data can be used for metrology level inspection and reverse engineering allowing for the correction of surfaces in the manufacturing process. Thanks to SHINING 3D’s scanner and its relative software tools, this is achieved through a highly automated process which requires minimal manual work. Using the FreeScan X5, the 3D data was thus collected and later evaluated in order to compare it against the data from last year’s version of the monocoque. The goal was to improve performance using the gathered information and analyzing the scan data to obtain a clearer idea of the tolerances for the production process.
In order to be amongst the forerunners of the Student Formula competition, students must invest a lot of time and energy into this project year after year. To better investigate the tolerance issues that arise during the manufacturing process, and to leverage this knowledge in the following years, the monocoque was initially covered with markers and then scanned over its entire surface using the FreeScan X5. This gave the students an understanding of how the vehicle compared to its original CAD model and allowed for the inspection process to take place. The scan also enables the vehicle to be compared to previous versions and, most importantly, it provides a benchmark for future versions of the monocoque.
The FreeScan X5 3D scanning process
The scan process is carried out relatively quickly for such a large object. Markers are placed throughout the vehicle and used as a reference for the FreeScan X5. Once this phase is complete, the students begin scanning the monocoque using the handheld laser scanner. The entire vehicle can be completed in a single scan, without requiring the 3D data to be pieced together manually. This saves users a considerable amount of time, as no manual alignment of the scan data is required: all the heavy lifting is carried out by the software.
The FreeScan’s software processes the image and creates a 3D model from the scan data which can be exported as a universal 3D file, an STL file also known as a meshed model. The images above and below show the resolution and accuracy of the 3D model created using the newly acquired data.
This meshed model is used by the students to demonstrate any deviations that the new vehicle presents as compared to its original CAD design. The image on below, on the left-hand side, shows the data obtained from the 3D scan, while the image on the right shows data from the original CAD model. The two models can be compared to determine tolerances with unparalleled precision.
The inspection report shows a CAD to part comparison in a helpful color map making it easy to understand the deviations. The software enables the comparison to seamlessly provide detailed information on differences between the two models.
Since important parts of the race car such as roll-bars are later attached to the holes on the monocoque, it was critical to ascertain information about the accuracy of component fit. These small details are what sets apart modern engineering solutions from outdated traditional methods. With the FreeScan X5, the students were able to digitize their entire process and limit the errors that traditional measuring tools can fall victim to.
If you’re looking for more information on how to modernize your 3D scan to CAD workflow or how to apply 3D scanning to your daily applications, reach out to SHINING 3D directly at [email protected]
This case study was created in collaboration with SHINING 3D