Research On Key Technique And Application Of The Precise 3D Optical Projecting Indication System

Projecting indication(argument reality guiding)is a new interactive display method to improve the quality and efficiency of manual works.A projecting indication system can be used to build a human-friendly interface for the measuring instrument and to show the analyzed feature data in a more intuitive way.In this dissertation,the principle and implementation of the projecting indication system is discussed in detail.The main points are as follows:1.A general design model for projecting indication system has been proposed in order to increase its applicability in a considerable large workplace.Be different with the self-guiding system,this new type of projecting indication system can be guided by 3D positioning equipment directly.The rigid body transformation is the basic principle of the proposed design model so this type of projecting indication system is compatible with almost all kinds of the projecting apparatus and 3D positioning equipment.To build specific projecting indication systems,the building procedure can be concluded into the following two main steps: projecting unit calibration and external positioning parameters calibration.2.The proposed system is realized with a digital projector and the general back projection model is derived with geometry relationship between digitized 3D model and the projector in free space.The corresponding calibration method is designed for the proposed system to obtain the intrinsic and extrinsic parameters of the projector.To validate the back projection model,the coordinate data collected by a 3D positioning equipment is used to calculate and optimize the extrinsic parameters.The final indication accuracy is verified in projector's subpixel scale.To further improve the indication accuracy of the digital projector,the calibration method which based on spatial beam capture is developed and fully verified.3.The proposed system is also realized with a two-dimensional galvo scanner and the corresponding back projection model is derived.Based on the proposed model,the calibration method for galvo scanner projecting indication system is developed with a camera and a calibration plate.Similar with the system with digital projector,the extrinsic parameters of the system with galvo scanner can also be calibrated by 3D positioning equipment.The final indication accuracy of this system is also verified.4.The relationship between the working position/orientation of the system and its indicating quality is analyzed.The local incidence angle of the projecting beam is selected as the benchmark for indication quality.Based on the proposed evaluation benchmark for indicating quality,a position and orientation optimizing algorithm is proposed for the projecting indication system.5.Two application systems are built to improve the quality and efficiency in production environment: 1.Composite material lofting and position indication system;2.Rapid rivets measurement and correction indication system for aircraft skin manufacturing.