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TECHNOLOGY 37
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It is important to note that this was one of the authors’ parts are scanned in 3D, imported into inspection software,
first projects. Due to a lack of experience, eight scans were and correlated with the CAD model of the same part. In this
captured, but only two were used. Experience helps engineers case, the inspection software was used to check the quality
optimise the number of scans needed. of the CAD modelling.

The final step is to create a mesh model. The great The created CAD models do not perfectly fit the scanned
advantage of the software used is that it is always possible data so that some deviations may occur. In the furniture
to go back and fix errors during raw data processing or to industry, all deviations below 1 mm can be accepted. The
carry out and add additional scans if necessary. The created results of comparing the scanned model with the CAD model
mesh model can be aligned to one of the planes before were presented.
exporting to the STL file.
Although the mesh model provides valuable visualisation Real-world Case Studies
capabilities, it cannot be directly used in CNC machining or Case Study No. 1
other automated manufacturing processes. Therefore, it was The undertaking described as case study no. 1’ was conducted

converted into a high-quality CAD 3D model using reverse by the Faculty of Mechanical Engineering at the University
engineering software (Geomagic DesignX, 3D Systems, of Sarajevo, collaborating with Bosnia and Herzegovina’s
Valencia, CA, USA). The reverse engineering software used Aptha Corporation as the producer. Stefano Bigi, an Italian
has commands for the creation of CAD models using scanned furniture designer, was author of the design of the analysed
mesh models only as a reference. It is easy to scan and piece of furniture.
process raw data, but to create a full-value 3D CAD model The design process began with creating initial concept
with topology, extensive knowledge and experience are needed. models in real size by hand. These physical models were then

The first step involved creating sketches using splines. brought into the digital realm using 3D scanning technology.
These sketches were then used to generate surface models. These scan data, initially in the form of a point cloud (STL
Once the surface model was completed, a solid CAD model 3D model), were the foundation for creating CAD 3D models
was created by adding volume to the surface. suitable for manufacturing. A prototype of a product designer’s
Additionally, a small rectangular prong was added using lounge chair was illustrated undergoing 3D scanning.
the standard Part Design modelling procedures. This prong In the first step, the product designer created a digital
is not visible because it did not require surface modelling design. In the second step, the mechanical engineers used
with splines; its simple geometry could be created directly that digital design to produce the first prototype.
using Part Design tools. The solid model itself was generated

through the regular Part Design modelling procedure, but with
the scanned data serving as a crucial reference. Sam Moghadam Khamseh
The CAD model can be used for manufacturing. However,
it is essential to compare the dimensions and tolerances with
those of the 3D-scanned model to ensure precision. Therefore,
inspection software (Zeiss Inspect Optical 3D v. 2023.2.0.1520,
Carl Zeiss AG, Oberkochen, Germany) was employed.

Inspecting software is usually used to measure the
dimensional accuracy of manufactured parts. Manufactured