The Fast and High-Precision Approach to Modern Automotive Design
Even in these modern times of high-technology and automated production, there are some areas in which machines do not have a role to play: a new automobile, for instance, first takes shape using a pen, paper and clay.
When creating a hand-shaped design model made of a special modelling clay, in particular the visible and thus design relevant free form areas play an important role. A car´s sporty or elegant appearance, for instance, is defined through individual ‘tornado lines’ or roof lines, tailgates or mud guards – result is the unmistakable and distinctive shape of a new automobile whose surface, thanks to using a SmartScan-HE for the first-time measurement, complies with every single quality requirement.
Fast digitisation of delicate objects
At first, the new vehicle model takes shape in a sketch with individual design features, shapes and character lines. In the subsequent step, the model maker takes this initial draft and converts it into an actual, three-dimensional prototype by layering specially processed modelling clay onto a wood-made base.
Based on this handcrafted clay model, refining elements and features can be added to the car exterior and initial aerodynamic studies can be carried out. For the subsequent development process, however, the designers require the digital data of the prototype. Given the soft and sensitive surface of a handcrafted model, the measurement with the aid of a coordinate measuring machine (CMM) is not an option; moreover, the CMM method does not deliver the necessary data density required for the computer aided styling (CAS) process. The solution is an AICON SmartScan, allowing for the fast and highly precise data acquisition of the draft model for the creation of a virtual 3D data replica.
In order to ensure Class-A quality surfaces right at the outset of the design process, a highly accurate measurement of the models is of vital importance. Only in this way can the data be reversed into a further processible CAD surface data set at the required accuracy and level of detail and be optimally prepared for the subsequent construction and manufacturing processes.
To perform the initial measurement of the clay model, the AICON SmartScan with a large measuring field is used. This 3D measuring system not only offers different measuring field sizes which can be easily adjusted to any respective measuring task in hand, but also provides very fast digitisation results as well as highly precise data for immediate further processing. For a partly automated data acquisition, the turnTABLE-300 which is specially designed for heavy measuring objects can be additionally used inconjunction with the SmartScan-HE.
Seamless 3D data set of a vehicle
The entirely contact-free scanning process is ideally suited for sensitive or fragile objects, whereby the actual digitisation project consists of two main phases: During the data acquisition the clay model is captured from every perspective with the aid of the AICON SmartScan. Subsequently, the individual scans are merged into a complete 3D data set with the aid of the AICON scanning software OptoCat. Potential scratches on the sensitive clay surface which have also been captured during the scanning process can be easily removed in the digitised data sets, therefore consistently delivering a flawless, perfectly smooth surface. The 3D data set is then exported to the reverse engineering software (i.e. Rapidfom XOR3), generating a coherent 3D surface model and providing it as a parametric CAD data set.
The clay model does not necessarily have to be entirely complete in order to create a seamless 3D data set: after three-dimensionally capturing one half of the model, in the post-processing phase the scan data can be mirrored and the two halves can then be assembled virtually to become a complete, symmetrical vehicle.
Faster design process and more efficient production
The 3D surface model created from the high-precision measuring data generated by the AICON SmartScan system serves as the ideal basis for all types of design and shape forming processes. The quick and flexible measuring process together with the high-level data density not only effect a much faster design process, but in general contribute to a much more efficient production flow. The possibility to scan only one half of a design model, then mirroring it and putting it together virtually, helps to achieve significant savings of both time and material at the stage of creating the clay model.
Upon completion of the reverse engineering phase, the data can be freely modified in scale and form and be used to shape actual 3D prototypes in different sizes for further tests and developments; rather than having to handcraft new models, this again contributes to considerable time savings. Furthermore, the information can be collected and stored in a digital design archive, enabling the development phases for the creation of a newly designed automobile to be documented in every single project stage.
In comparison to the conventional coordinate measuring machine technique, the AICON SmartScan delivers a significantly faster and easier interpretation of the measuring results, in particular in connection with free form areas. The user is provided with a much more comprehensive, and yet easier and more efficient data basis for further processing in the prototyping phase which in turns helps to considerably accelerate the overall time to market cycle.