3D Scanning and Reverse Engineering in Nepal: Applications

3D Scanning is the process of capturing surface of the real world objects into digital 3D form with the use of light or LASER technology. The process can capture the shape, size and appearance with high level of accuracy. In General, the common 3D scanner types are: 3D Laser scanners, Structured Light/White Light scanner, Photogrammetry and Optical CMM (Coordinate Measuring Machine). The quality and accuracy of the data depends upon the type of scanner or scanning technology used and performance capacity of the scanner itself.

3D scanning technology has been around in the global market for decades but its use has been limited to few due to its high cost and in-depth technical knowledge required both during the scanning process and for post-processing of the scanned data. Not to mention Nepal has yet to scratch the surface in the world of 3D scanning.

Zener Technologies started the commercial 3D scanning services in Nepal in 2018. Since then, we have been exploring its applications in various sectors; and the potential it has got in accelerating the growth and development of related fields.

It is a very powerful tool for precise documentation, measurement and re-construction of existing parts. The field of application extends but not limited to: Architecture, Reverse Engineering, Interior, Medical & Prosthetic, Archaeology and heritage preservation, and many more. Let’s discuss the applications of 3D scanning in Nepal we have explored so far:

  1. Reverse Engineering and Metrology: Reverse engineering is the process of taking an existing object and documenting it and exacting parameters such as dimension, shape and size. Thus, creating alike objects (if not new) from the existing one. 3D scanning first captures the point cloud data of the object which can be reconstructed to generate a 3D mesh model. The mesh model then can be used to generate the 3D CAD model in different CAD software. The object then can be used for 3D printing, die making and production. Thus obtained 3D objects can also be used in analysis, deviation studies and modification of the original one.

Similarly, metrology is the study of the size/measurement of an object. Not all objects or all areas/part of the object can be precisely measured using physical measuring tools such as vernier Caliper, measuring tapes etc. In such cases 3D scanning comes in handy. 3D scanned data with a high level of accuracy can be used in documenting the measurement of objects efficiently. The data can then be used to modify the existing object or to scale to different size as per requirement. 3D Scanning has a profound application in capturing turbine failures in 3D and analysing it for better repairing. We have had experience working with the Kaligandaki and Jhimruk Hydropower turbine runner and vane to support the PHD thesis for KU and IOE-Pulchowk researchers.

Image: Scan Data obtained after 3D scanning the Jhimruk guide vane model. This non watertight model (right) is used for reverse engineering in CAD software to obtain smoother watertight 3D models (left).

Image: CAD model (left) by using scanned mesh file (right) of the vane profile. The model was for research work in a turbine lab.

  1. Medical and Prosthetic: It is very useful in taking the measurement of organs to develop personalized assistive devices, prosthetic parts in depth study and to prepare surgical guides. Owing to the fact that every individual’s shape and size differ, 3D scanning enables patient-specific data creation. It can equally be used to generate teaching/learning anatomical models in medical education or to make a dummy model to simulate complex surgeries before going for actual surgery.
Image: Mr. Sanjeev lost his lower feet due to an unfortunate fire accident in his childhood. A pair of custom shoes were required for the ease of his mobility. The production of which required the exact shape and form. Grey is 3D printed part of his left and right foot. We 3D scanned both feet and 3D printed it in real scale. The printed parts were then sent to the prosthetic factory to design custom shoes  that would perfectly fit Sanjeev.

  1. Dental: Digital dentistry can benefit most from 3D scanning technology. The impression of the patient is converted to a plaster of paris (POP) sample which is then 3D scanned to get the digital CAD model. The 3D model then can be used for planning braces, surgical guide and preparing dentures, crown using milling machines. Read this interview with Dr. Ujwol Pakyural, Shangrila Dental Clinic to know more about Digital Dentistry in Nepal.
Image: 3D scanned teeth model (top) of one of the cases for Dr. Ujjwol Pakyural ‘s patient. The model is then 3D printed (bottom). 

  1. Art and Craft: Bringing imagination or a picture into a physical clay/wax model is a lengthy and highly resourceful task to the craftsmen. Creating multiple size variations of the same model is a nightmare – months of work for a skilled hand. But, once you have a master piece, 3D scanned data of idols, sculptures and artefacts can be easily converted into varying sizes which would be much more useful to produce different versions of the existing original one – just a couple of clicks to scale to sizes after a 3D model. The masterpiece produced from 3D printing can be used for further mass production using traditional casting methods. Besides these, the metrology data acquired from any smaller object can be used to generate the accurate data in construction of very large forms of the same object. For example: data generated from a small Buddha idol can be used as a reference for the construction of Buddha Park with 100 or 200 ft tall Buddha idol.
  1. Research: 3D scanning can be well applied to the field of research and development. In the case of Nepal, it’s been used by PhD research scholars and young engineers for their research projects to study the erosion of existing mechanical parts. In fact the following is the very first 3D scanning cases in Nepal in the field of turbine study, carried out inside Nepal.
Images: Eroded guide vane of Jhimruk Hydropower Station, pyuthan study carried out by Shahker Aryal as a part of his PhD program, Pulchowk Engineering Campus. Zener Technologies scanned the model using a handheld structured light scanner.

  1. Heritage restoration and preservation: It is a well-known fact that the precious heritage gets destroyed or damaged during disasters like the Nepal earthquake 2015. The remnants of valuable patterns, idols and artefacts in such cases can be 3D scanned to create a digital copy of an object which can be used to produce the exact replica during the restoration project. Furthermore, the skills and technique besides traditional idol making is dwindling, so for the sake of future generations it is good to keep a 3D copy of such items by creating digital archives to last forever. The technology was very well used in the case of Notre Dame, France restoration project as well.
Images: Keshar mahal case study showing the restoration process from 3D scanning a masterpiece to a replica of it.

These are the very few sectors which have adopted the application of 3D scanning but very rarely and low count. Phenomenal leap can be made in many other sectors and the potential is yet to be explored. And with advancement it is inevitable. We are constantly promoting the sector with training, workshops and free consultation. Technology transfer and knowledge workshops are key to our business.