| As one of the advanced composite automatic manufacturing technology with low-cost, Automated Placement Technology(APT) has become typical processes for fabricating large composite material part in the fields of aeronautics and astronautics in developed countries with high-efficiency, high-quality, high-precision and high reliability, which is more difficult by manual. The domestic study is still at the starting stage.APT used dedicated CNC equipment to place tape or tows on surfaces with compaction system. It implements the distribution of fiber direction and layout to achieve the requirements and make full use of materials efficiency. APT is the integration of equipment technology, CAD/CAM software technology and material technology, including ATL and AFP. As a part of these projects,"Research on Automated Tape-Laying Technology and Equipment Technology for XXX Tube Segment Composites","Research on Equipment Technology and Application Technology of Automated Tape-Laying Machine for Large Composites","Fundamental Research on Technology and Equipment Technology of Automated Fiber Placement Machine"and"Research on Automated Fiber Placement System", the trajectory generation, coverability, boundary treatment, post processing and manufacturing simulation of automated placement CAD/CAM software technology were studied for applications on an airplane tail section and horizontal tail section. The automated placement CAD/CAM software was developed with the platform of CATIA CAA which is widely used in the flied s of aeronautics and astronautics and the software is verified by practice. The primary work and achievements are summarized as follows:1. Based on preliminary work, the previous algorithm is analyzed and the trajectory generation is researched. (1) The clearance of APT is researched at first in this thesis; the clearance process design requirement is introduced to"Natural Path"algorithm. Compared with clearance requirement, used arc-length difference of tape sides to measure deformation, a new trajectory generation algorithm is constituted. By adjusting the angle, the starting point, step approach to construct proper trajectory, the algorithm not only to meet the design requirement, but also to ensure the laying without fold and tear.(2) With given fiber orientations of points, the distribution function of fiber placement directions was constructed by the Least-squares Method. A trajectory generation algorithm was proposed and realized by which the fiber orientation can be designed along the function due to variable angle planning. 2. The coverability of automated placement is researched. The algorithm of centerline spacing between adjacent trajectories based on geodesic and meshes is analyzed. A variable step coverability analysis algorithm based on geodesic line is proposed. According to the characteristics of geodesic line, the corresponding relationship between tow's number and distance of adjacent path centerlines is constructed. Add or reduce the tow are determined based on design requirements. The algorithm not only satisfies the structural design requirements, but also improves the efficiency to achieve the practical engineering requirements.3. According to technical characteristics of ATL, the work module and dimensions of prototype the single-phase and two-phase ATL is analyzed and different cutting patterns of single-cut and double-cuts are studied. The uniform boundary treatment is proposed base on arc-length .The treatment can be applied to boundary treatment of AFP according to the relationship of tow position of AFP and cutter offset. The uniform inside and outside boundary treatment is constructed suitable for single-phase and two-phase ATL, single-cut and double-cut cutting-system and AFP.4. An APT CAD/CAM Software is developed under the platform of CATIA CAA technology and Visual studio .net 2003 based on user requirement analysis and used MySQL for data exchange and storage. The software has good expansibility and is verified by practice.
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