由于薄壁多框体结构件的弱刚性，在加工过程中因装夹方式不当很容易产生加工振动和变形，影响加工精度和加工效率。为此，本项目拟以薄壁多框体结构件的夹具设计为研究对象，以提高零件的加工精度和加工效率为目标，以多跨度板模型替代薄壁多框体结构件模型，利用瑞利能量法和瑞利-里兹方法建立多跨度板动力学响应的数学物理方程，进而根据柔性多体系统动力学理论建立“工件-夹具-刀具”系统的加工动力学模型，利用浮动坐标系方法和现代微分几何理论建立工件在加工过程中整体变形的数学模型。在此基础上，建立反映工件在加工过程中的振动和铣削稳定性以及工件在加工过程中材料去除影响的夹具设计方法，并利用时间有限元分析方法和谐波平衡方法建立薄壁多框体结构件铣削加工表面位置误差、铣削稳定性以及加工表面形貌同时预测的数学模型，实现薄壁多框体结构件的高效高精加工。

As the low rigidity of the thin-walled multi-frame structure parts, improper fixture layout is apt to generate the machining vibration and deformation, which will seriously affect the machining accuracy and efficiency. Therefore, in this project the fixture design for thin-walled multi-frame structure parts is studied. The goal is to improve the machining accuracy and efficiency of the parts. The model of thin-walled multi-frame structure part is substituted by the multi-span plate model. Both the Rayleigh's energy and the Rayleigh-Ritz methods are used for the calculation of the response of the multi-span plate. The machining dynamics model of the workpiece-fixture-cutter system is established according to the dynamics of the flexible multi-body system. Both the float frame approach and the modern differential geometry theory are used for establishing the mathematical model of the machining global deformation of the workpiece. On this basis, the fixture design for thin-walled multi-frame structure parts based on the dynamic machinability analysis and the change of thickness due to the material removal action is established. The mathematical model for simultaneous prediction of the surface location error, the stability and the surface topography is built by using the temporal finite element analysis and the harmonic balance method. This will achieve the efficient machining and high precision machining for the thin-walled multi-frame structure parts.