A Study On Human-computer Interaction For User Experience In Virtual Assembly Environment

When a virtual assembly system combines human experience and decision making ability with computing power of computers,it will assist the assembly design planning and verification,and help save design and manufacturing cost.Human computer interaction is the basic of the virtual assembly system.However,at present,the design of virtual assembly system focused on its function and technology,but ignored the human interaction experience,failing to play advantages on the interactive features of virtual reality technology.Therefore,the virtual assembly technology has not been widely used in the industry.The thesis investigated thoroughly the key theory and technology of human computer interaction in virtual assembly application field.From the view of users and based on the concept of perceptual mechanism and user-centered design,the objective of this paper is to establish a natural and harmonious human-computer interface for the virtual assembly environment.In that,the intelligence of the virtual assembly system can be improved and the cognitive and operating loads reduced in the interactive process,leading to realize the change of the virtual assembly system from function to user interaction experience.In this thesis,the human computer interaction strategy in virtual assembly environment is proposed.The reasoning and simulation of interactive behaviors by double-layers perception mechanism and active object technology is to realize a natural and harmonious human-machine interface for the virtual assembly environment.The main principles include:(1)the interactive information is integrated into the virtual assembly environment,so that static virtual scenes and virtual objects contain numerous interactive information;(2)based on the integrated interactive information,the two-layer perceptual mechanism is used.The outer layer corresponds to the physical world in which the user is located,and the action information of the user's operation perceived.The inner layer corresponds to the virtual world in which the active object exists.Through developing the small world situation in which the active object exists,the user's interactive intents are perceived and the interaction of the objects predicted;(3)based on the intentions of user's interactive intents,the interactive behavior simulations of the objects are performed,and the interactive behaviors are fed back to the users by multi-channels.The contents of this thesis are as follows:1)An interactive information integration strategy in virtual assembly environment is proposed.This thesis analyzes the characteristics of interactive objects in virtual assembly environment,proposes the concept of interactive features and describes the behavior interaction between interactive objects in the interactive activities through interactive features.Interactive feature attributes are embedded into the geometric models of virtual objects,in that the geometry models of objects are correlated with the interaction behaviors to form the behavior mapping model of interactive objects and realize the integration of interactive information in virtual environment.By interactive semantics,the interactive behavior information in virtual assembly is formally described and interactions among the components of product assembly and operative semantics information are extracted,to form a reusable behavior component for the interaction object.In certain interactive activities,using the interactive object behavior mapping and interactive semantic model instantiates correspondingly the object interaction.It provides the basic for user intentional reasoning and interactive behavior simulation.2)Based on motion perception,an interactive information recognition method is proposed.In the process of human computer interaction,the gesture recognition is introduced into the main channel of user interaction information input.The hierarchical interactive gesture model is established according to the characteristics of assembly task and interactive mode,that is two-level gesture classification strategy.Firstly,the interactive gestures are preliminarily classified,and the gesture type is judged by the context perception technique.Then,the interaction semantics of the gestures are further identified by the motion perception technique.The modeling methods and recognition algorithms are developed for different types of gestures.3)The object behavior reasoning method is proposed based on the context perception of active objects.According to the activity theory and the analysis of the human context perception,the relationship between the hierarchical structure of the assembly activities and the context perception process is obtained.According to such a relationship,the context perception mechanism based on the active objects is proposed.Interactive spatial perceptual algorithms of the virtual objects are designed,and the potential interactions of users referred.4)An object interaction behavior management method integrated the geometric constraints and physical behaviors.The characteristics of user behaviors and object behaviors of each component of assembly task are analyzed,in that the interactive behaviors of virtual object are divided into the free operation stage and the task operation stage.Different interactive technologies support different stages.The object behavior management in the free operation stage is realized by the physical interaction technology.The interactive behaviors of the task operation stage are supported by the constraint interactive behavior.In order to embody the "user-centered" design requirements,the object interaction behavior management technology for integrating geometric constraints and the physical behaviors are evaluated and the results discussed.5)Based on the multi-channel integration,a full hand interactive human machine interface and prototype system is designed.A whole hand feedback virtual peripheral with six freedoms(6-WHFD)is developed to support user to output interactive gestures and feel feedback information.Based on 6-WHFD,a virtual assembly design prototype system is developed for natural interactions.The 6-WHFD human-machine interface and prototype system is verified by the application.