Object registration using an RGB-D camera for complex product augmented assembly guidance

Background Augmented assembly guidance aims to help users complete assembly operations more efficiently and quickly through augmented reality technology,breaking the limitations of traditional assembly guidance technology which is single in content and boring in way.Object registration is one of the key technologies in augmented assembly guidance process,which can affect the location and direction of virtual assembly guidance information in real assembly environment.Methods This paper presents an object registration method based on RGB-D camera,which combines Lucas-Kanade(LK)optical flow algorithm and Iterative Closet Point(ICP)algorithm.An augmented assembly guidance system for complex products through this method is built.Meanwhile,in order to compare the effectiveness of the proposed method,we also implemented object registration based on an open source augmented reality SDK Vuforia.Results An engine model and a complex weapon cabin equipment are taken as an case to verify this work.The result shows that the registration method proposed in this paper is more accurate and stable compared with that based on Vuforia and the augmented assembly guidance system through this method greatly improves the user's time compared with the traditional assembly.Conclusions Therefore,we can conclude that the object registration method mentioned in this paper can be well applied in the augmented assembly guidance system,which can do enhance the efficiency of assembly considerably.

Research on the visual elements of augmented reality asse mbly processes

Background To solve the problem of visualization in augmented reality(AR),for assembly process information,we report here on our study into the composition of AR assembly process information.Methods Our work led us to classify the visual elements of assembly processes into six categories,and after looking further into visual element expression characteristics used in assembly process information in the AR environment,standard assembly process elements have been identified and visual element layout principles studied.Conclusion Typical visualization elements have been presented,using an AR-based assembly instruction system.

A comprehensive survey of augmented reality assembly research

In the past two decades, augmented reality （AR） has received a growing amount of attention by researchers in the manufacturing technology community, because AR can be applied to address a wide range of problems throughout the assembly phase in the lifecycle of a product, e.g., planning, design, ergonomics assessment, operation guidance and training. However, to the best of authors＇ knowledge, there has not been any comprehensive review of AR-based assembly systems. This paper aims to provide a concise overview of the technical features, characteristics and broad range of applications of AR- based assembly systems published between 1990 and 2015. Among these selected articles, two thirds of them were published between 2005 and 2015, and they are considered as recent pertinent works which will be discussed in detail. In addition, the current limitation factors and future trends in the development will also be discussed.