This paper proposes a three-dimensional impact angle-constrained nonlinear guidance strategy against different types of targets. To avoid the occurrence of singularities, in Euler angle-based approaches, the development of this guidance strategy is solely based on quaternion dynamics. An explicit relationship between the quaternions representing impact orientation and line-of-sight orientation at the time of collision is derived. Based on the obtained relation, a guidance law is derived using a sliding mode control technique to track the desired line-of-sight orientation for target interception. The performance of the proposed guidance strategy is evaluated for constant-speed and different time-varying-speed interceptor models accounting for the effect of varying aerodynamic parameters on interceptor speed. The numerical simulations performed show satisfactory results for all engagements, validating the efficacy and robustness of the proposed guidance law.

中文翻译：

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用于三维啮合的基于四元数的非奇异非线性冲击角制导


该文针对不同类型的目标，提出了一种三维弹射角约束非线性制导策略。为了避免奇点的出现，在基于欧拉角的方法中，这种指导策略的开发完全基于四元数动力学。导出了碰撞时表示碰撞方向和视线方向的四元数之间的显式关系。基于获得的关系，使用滑模控制技术推导出制导律，以跟踪目标拦截所需的视距方向。考虑到不同空气动力学参数对拦截器速度的影响，评估了所提出的制导策略在恒速和不同时变速度拦截器模型下的性能。进行的数值模拟显示所有交战的结果都令人满意，验证了拟议指导法的有效性和稳健性。