Research On Collaborate Assembly System Design Based On Augmented Reality

Augmented Reality (AR) is a promising technology which can enhance the sense of reality by combining virtual information, including models and sounds, with real ones. Augmented Reality has been applied in many fields, e.g. medicine, manufacturing, military, education, entertainment.Assembly technology aims to develop fast, reliable and low cost method to improve product design in the manufacturing industry. Traditionally, physical prototyping is the main approach for assembly design, which is very expensive and time-consuming, especially when some modifications of the product are made and the prototype needs to be produced again. With the advancement of computer-aided technologies, assembly operations become more and more automated. Virtual assembly has significantly promoted the development of assembly technology. Virtual Assembly is performed in an artificially generated 3D environment and virtual geometric models are utilized to represent assembly parts, which is less costly and faster than traditional physical prototype method. Virtual assembly also has its limitation that the assembly environment is a pure virtual scene with no real objects in user's environment. When AR technique is applied in assembly to develop an AR-based assembly system, it can provide more intuitive and natural interactions and make assembly task more reliable and effective than traditional assembly techniques, because AR can enhance the sense of reality using virtual information.This paper presents a framework of the AR-based collaborative assembly system. Several key techniques in the system are described in detail (e.g., registration, collusion handling, collision detection, human-computer interaction, kinematics simulation). The collaborative AR-based assembly system aims to allow users to view a product model from different perspectives and cooperate to tackle an assembly task using C/S structure. The occlusion handling method is applied to obtain the correct occlusion relation between real and virtual parts; An effective collision detection algorithm is used to determine the part-part constraint situation and users'interactions with elements in order to indicate that there are collisions occurring during the assembly process; A series of interaction tools are developed aiming to mimic 3D interactions in the real environment, not simply traditional 2D mouse and menus. They are a panel, a pen and a glove. The paper also presents a novel method for kinematics simulation between real and virtual parts in order to help users to evaluate the product design. When the parts are assembled, a simple kinematics simulation is implemented for the product evaluation based on the features and geometrical information of the parts. Based on the above techniques, a prototype system is developed and the results of many experiments have proved the effectiveness of this assembly system.