| The aero-engine is a complex system with extremely complicated structure and highly concentrated technology, the application and maintenance of which are both greatly demanding proficient technicians. Therefore, this thesis which is aimed to raise the maintenance level of the aero technicians, lower the difficulty level of maintenance and research into the method and technology of maintenance will be of great significance. Taking the typical aero-engine maintenance work in the outside field as an example, combining the basic wearable maintenance aid theory and the augmented reality technology, this paper has done a deep research into the key digital maintenance technique and has developed a personified and intelligent maintenance aid system, centered on the maintenance technicians. This maintenance aid system can be applied to train the technicians and give them directions, lower the difficulty level of the maintenance work and reduce the errors in the process. The main content and innovation in this paper may be summarized as follows:(1)It has advanced a theoretical model of augmented reality systematical registration algorithm, dividing the complicated markerless registration problem into four manageable stages as features extracting, matching, 3D reconstruction and merging virtual and real scene. Taking the advantage of virtual visual servo and structure from motion technology, tracking the image serials'point features and linear features, this paper has realized augmented reality registration algorithm. The result of the experiment has verified the effectiveness of this approach.(2)Based on eye gaze tracking technique, through electromagnetic position tracker and the position tracking algorithm using four coplanar markers, this paper has constructed two sets of eye gaze tracking system of head fixed and head unfixed. By the analysis of the experimental data, the average tracking error of the two sets of eye gazing system is 0.9585o and 9.5871mm.By integrating eye gaze tracking system and augmented reality optical see-through HMD, it has constructed augmented reality natural interactive optical see-through HMD equipped with eye gaze tracking function and has laid a good foundation for developing the augmented reality maintenance guiding system.(3)The organization and expression of augmented reality maintenance guiding system is a key issue. This paper has corresponded aircraft maintenance manual, EBOM figure and virtual prototype data, and transferred aircraft virtual prototype data of the designing section into demanding virtual prototype of augmented reality maintenance guiding system which can be rapidly and lifelikely displayed in augmented situation. It has greatly improved the efficiency of the model construction and the quality of the model.(4)This paper has constructed maintenance guiding task net model, including maintenance description model, maintenance guiding model and maintenance technicians competence evaluation. It has well solved the three problems of maintenance description, information synchronization and human computer interaction, maintenance capability assessment. Centering on MGTN control model, taking command interpretation module and motion perceptual model as data input, information augmented module as output, with the help of scene analysis module and information retrieval module, the paper has completed the augmented reality maintenance guiding process.(5)Based on APU load compressor endoscopy work card, applying three divisional registration technology, person-computer natural interactive technique, IETM and MGTN maintenance knowledge description method, this paper has realized an augmented reality maintenance guiding prototype system. Through the maintenance equipment dissembling and installation in the process of work card, endoscopy graph reconstruction and demonstration of evaluation, this paper has displayed that the augmented reality maintenance guiding system will play an important role in aircraft maintenance.
|
PDF Full Text Request