针对 IDVD（Inverse Dynamics in the Virtual Domain）轨道优化算法中节点等距分布导致其使用率低的问题，提出了一种变节点 IDVD 轨道优化实时算法。该算法基于过载对虚拟路径的变上限积分，先后进行两次优化，将固定节点、固定步长的 IDVD 转化为变节点、变步长的 IDVD。与应用 IDVD 算法拦截上升段弹道导弹的两个实例进行对比研究，在总节点数相同的情况下，变节点 IDVD 比 IDVD 方法计算的弹道误差标准差在 X、Y、Z 轴降低了约20%，优化时间缩短了约20%。研究结果表明：变节点 IDVD 算法能够按照虚拟路径曲率的大小自适应分配节点，有效提高了节点的使用率，继而提高了弹道计算精度，缩短了在线优化时间。
To solve the problem of low utilization rate in IDVD（Inverse Dynamics in the Virtual Domain）trajectory optimization caused by the nodes distribution in equal distance, a variable node IDVD trajectory optimization real time algorithm is presented in this paper. The algorithm based on variable upper limit integral of overload on the virtual arc transcribes fixed node and fixed step IDVD to variable node and variable step IDVD by optimizing twice. Compared with two examples using IDVD in the interception of BM trajectory at ascend phase, if the number of nodes is equal, variable node IDVD reaches lower standard deviations of error of 20% at x axis, y axis, z axis approximately, and cuts the optimization time by 20% approximately. Results show that the variable node IDVD is able to distribute nodes adaptively according to the size of curvature of virtual arc, which improves utilization rate of nodes, increases trajectory calculation accuracy and decreases online optimization time.
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