Development of an In Situ 3D Profile Measurement System Using Laser Displacement Sensor for Parts through Reverse Engineering for Additive Manufacturing Applications

Additive manufacturing (AM) is a complex fabrication process comprised of a multitude influencing process parameters and potential fluctuations leading to inconsistencies in properties, defects and imperfections in fabricated part. To overcome these inconsistencies, in situ monitoring of the part during fabrication is very much required to meet the challenges which restrict the improvement of process. In this communication, an attempt has been made to develop a 3D profile measurement system using Laser Displacement Sensor (LDS) for reverse engineering (RE) and in situ profile monitoring of the surface geometric signatures formed during deposition layer by layer in hybrid AM. 3D model of different shaped objects are created, adopting different scanning processes, by constructing the 3D surface through mapping of the point cloud data of multi scans in MATLAB. The 3D model created in MATLAB in STL file format can be transferred to any 3D CAD modeling software for editing the model to improve the product quality by addition or deletion of features or for direct AM application. This experimental study will provide a cost-effective solution by resolving the process limitations. The outcomes of this study will enrich the fields of RE. It will also play a vital role in hybrid AM to monitor the layer height in situ and path planning for the process. Linear path scanning for surface, rotary path scanning and cartesian scanning methodology by LDS have been adopted to scan the objects of different shapes. The surfaces are formed in STL file format in MATLAB platform. Then the STL file is transported to a system with suitable 3D CAD modeling software for 3D model of the object which is editable one and can directly be applicable for AM applications. From the experimental study, the maximum deviation in dimensions of the actual object and the 3D CAD model developed for rectangular block, square block and heart shaped object obtained is 1.06%, 1.17% and 0.05% respectively.