Recently there has been an increasing demand for models to be created based on an existing object or prototype, a process known as reverse engineering. This field is mostly centered on the reverse engineering of physical objects, which involves taking a physical prototype part and producing a CAD model of it. This requires both model reconstruction techniques and manufacturing expertise, as well as a deep understanding of the physical attributes of the object being replicated. Below we will describe how our 3D modeling engineers were able to reverse engineer a car windscreen for Fuyao Group, the biggest supplier of automotive glass in China.
1. This project involved working with a complex curved object, presenting a number of challenges when it came to measuring it. It was essential that the surface dimensions were measured completely accurately, and with the windscreen bending and flexing it meant an unusual level of care was required.
2. The client specifically mentioned they required top-level engineering on the reproduction of the curved surface of the windscreen, as well as on the gaps between the windscreen and the other curved surfaces at the edges. The changing tangency and curvature of the surfaces also needed to be dealt with perfectly. All kinds of glass involve some degree of bending and flexing, and for such a large curved glass object like a car windscreen, this flexing is significant both vertically and laterally. For our model engineers this presented an additional layer of difficulty.
The 3D modeling data used for the reverse engineering mostly comes from 3D scanning. At ProtoFab we use Canadian company Creaform's handheld 3D laser scanner. This equipment can scan objects from 10 cm to 4 meters in length, making it a useful tool for getting an accurate scan of large objects. We first scanned the surface of the windscreen to get some initial data, as shown below.
Results of 3D scan
After generating a point cloud, our engineers extracted the features and processed the data using specialist software. This included a small degree of filtering and adjustment, necessary due to imperfections in the sample itself and a number of other factors. Using the point cloud as a reference, we then used specialist software (Unigraphics NX) to complete a more detailed model. Our engineers then needed to make further adjustments based on the curvature data to ensure that the model matched the original as accurately as possible.
Completed model of windscreen
After completing the model, we sent the results to the client for checking. They used various software to verify that the model was accurate and that it could feasibly be reproduced. This stage required a lot of back-and-forth communication between ourselves and the client, and a few minor adjustments were made. The engineers at Fuyao were very pleased with the digital model and were able to use it for future mold analysis, mold testing and NC machining, speeding up their development phase.
Reverse engineering can be used as a method to restore objects which are damaged or worn, as well as to digitize objects for testing or further development. This technique has been used in wide variety of industries, including the automotive, aerospace, footwear, healthcare, and consumer electronics industries. In future, the technique is likely to find innovative uses in an even wider range of fields.
ProtoFab has a large team of highly qualified designers and engineers capable of providing an unparalleled level of service. Whether it's industrial design, prototyping, low-volume manufacturing, mass production, or all of the above, ProtoFab is the only place you need to go. If you have a project similar to the one above, or any other requirements, we’d be delighted to hear from you.