To increase usability or ease of use of certain products, improvement in previously designed products is required. Some products in current use were designed with no design data stored such as their physical or digital drawings to refer to make improvements in current products in use. Some products with small and complex features and internal designs difficult to observe or measure with no digital data on design become difficult for design up-gradation. In such cases, 3D scanning and reverse engineering come in hand for product design up-gradation or new product development.
3D scanning is the process of analysing a real-world object or environment to collect data on its shape and possibly its appearance. The collected data can then be used to construct digital 3D models. The data obtained as the output is point cloud data which is worked upon on various tools to obtain a solid 3D model. The 3D scanner has somewhat characteristic of capturing the shape and colour data of the objects. In most cases, multiple scans are required on product from different angles to give data of shapes from different sides and these scans are combined to give actual point cloud data of the object which replicates the shape of the object. 3D scanners can be contact types like CMM or non-contact types like portable and handheld 3D scanners. The common applications of this technology include product design/development, manufacturing, augmented reality, motion capture, gesture recognition, robotic mapping, industrial design, orthotics and prosthetics, reverse engineering and prototyping, quality control/inspection and digitalization of cultural artefacts. These data are used extensively in the entertainment industry in the production of movies and video games, including virtual reality. The type of scanning technique to be used depends on product size, the complexity of design and the accuracy of output required. The accuracy of the 3D scanner for general purpose use is 0.01mm to 0.1mm.
The point cloud data obtained through 3D scanning is of not much use until the solid model based on the data is not constructed using reverse engineering tools. The STL format point cloud data is cleaned for the noise with unwanted data removed and the data is aligned with the planes for ease of various operations to create a solid 3D model. Various textures and colours can also be captured by 3D scanning and modelled accordingly to replicate the available solid product. This technique helps in easing the measurement task on a product which is difficult due to its size or its location.