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桁架结构夭线型面的无源控制是通过改变节点坐标的方法来实现的,这就是让预变形结构在已知载荷作用下变形回到原设计(无预变形)的几何形状。预变形的几何形状是通过每次迭代改变节点坐标来达到的,并采用一个已知载荷作用下产生的大小相等方向相反的变形。为此,假定桁架的结构型式、材料性能与边界条件以及载荷数据都是已知的。这个方法分四种情况来加以阐述,情况Ⅰ～Ⅲ采用了一个静定桁架。情况Ⅰ中的预变形结构的几何形状与情况Ⅰ中的预变形天线型面形状,都是在单组载荷作用下查找实现的。在情况Ⅲ中试图寻找能同时满足两组载荷的单一的预变形天线型面几何形状,并且找到了一个平均预变形的型面形状。情况Ⅳ研究了单组载荷怍用下的不静定桁架。所有四种情况下预变形结构的迭代收敛性都是又快又单调的。
Passive control of the truss structure of the projectile is achieved by changing the coordinates of the nodes. This is the geometry that allows the pre-deforming structure to deform back to its original design (without pre-deformation) under a known load. The geometry of the pre-deformation is achieved by changing the coordinates of the node at each iteration and using the same magnitude and direction of opposite deformations produced by a known load. For this reason, it is assumed that the truss structure type, material properties and boundary conditions, and load data are known. This method is divided into four cases to elaborate on the situation Ⅰ ~ Ⅲ using a statically determinate truss. The geometry of the pre-deformed structure in Case I and the shape of the pre-deformed antenna profile in Case I are all found under a single set of loads. In Case III, we sought to find a single pre-deformed antenna geometry that could satisfy both sets of loads simultaneously, and found an average pre-deformed profile shape. Case IV studies the statically indeterminate truss for a single set of loads. The iterative convergence of the pre-deformed structure is fast and monotonous in all four cases.