Blackstone Tek (BST) in Johannesburg, South Africa is the biggest carbon fibre wheel manufacturer in the world. BST also makes other carbon fibre components for iconic motorcycle and automotive brands.
BST set out to design the most innovative electric motorcycle with renown designer Pierre Terblanche, who was responsible for styling Ducati motorcycles like the 999, HyperMotard and SuperMono.
CAD was used to design the “mule” prototype, whilst some parts were hand-sculpted to achieve an organic aesthetic.
Digitising Compound-curved Parts
The challenge was then digitising the hand-sculpted, compound-curved, “organic” components into 3D CAD models that could be used to CNC machine moulds for production lay-up of the carbon fibre parts.
3DWORX in South Africa was approached to 3D scan these hand-sculpted parts so that the entire motorcycle design could be represented in CAD.
An eviXscan HD Optima 3D Scanner and eviXscan Suite 3D Scanning software were used to 3D scan the parts, and Geomagic Design X software was used to reverse engineer them into 3D CAD models.
The HD Optima is a professional metrology-class 3D scanner used for reverse engineering and contactless quality control.
It has an extremely high accuracy and point density which enables it to achieve an accuracy certified to VDI/VDE 2634 Part 2, 4.1 P metrology standards in the EU, whilst still being a mobile device due to its rugged construction.
Hybrid CAD Modelling using Geomagic Design X
A hybrid 3D CAD modelling technique using CAD splines and flat surface underneath would have to be used to create the 3D models.
Up against the clock to complete the prototype, a quick method had to be found, and 3DWORX knew that Geomagic Design X Pro would save days of work, with its ability to quickly generate a surface model.
3D Scanning and Reverse Engineering Process
Five steps were needed from 3D scanning the parts to finishing the complete 3D assembly model of the bike.
Step 1
The patterns were sprayed with an extremely thin, white contrast and eviXscan unique markers were attached.
Step 2
The two side patterns were 3D scanned with the eviXscan HD Optima 3D scanner, and the unique markers enabled quick, accurate pre-alignment of the multiple scans sets using the eviXscan Suite software.
Step 3
Geomagic Design X software was then used to merge the various scans, remove the coded markers and fill the holes in the mesh digitally. Further digital refinement was applied to remove the hand-sanding marks and smoothen the surface.
Step 4
The “organic” surface contours were converted to CAD features that CNC/CAM would understand – a special capability of Design X.
Step 5
The final goal was achieved when the 3D CAD models of the contoured surfaces were exported and incorporated into the full CAD assembly of the entire motorcycle.
eviXscan 3D and Design X helped complete the prototype against a tough deadline. Parts had to be machined, 3D printed and painted (eg. those in green) in time for BST to crate the bike and airfreight it for unveiling at a show in Milan, where it received international applause.
Some Reflections on the Project and Tools
The above real-world example illustrates how engineers can rapidly create solutions to complex manufacturing and production problems when they access to the best toolset and skills.
Geomagic Design X is the most capable reverse engineering software available and can export 3D parametric models – including the geometries, topologies, modelling histories, and parameters – directly to popular feature-based CAD systems including Autodesk® AutoCAD®, Autodesk® Inventor®, Autodesk® Fusion 360®, CATIA®, PTC® Creo®, Siemens® NX™, Siemens Solid Edge®, and SOLIDWORKS®.
The combination of eviXscan’s various 3D scanners, the eviXscan Suite of software (included with scanners) and Oqton Geomagic Design X offer great value for money for the professional engineer, for reverse engineering and optical inspection for quality control.
