Multi-constraint three-dimensional vector guidance for maneuvering targets without active speed control

This paper proposes a three-dimensional (3D) guidance strategy to intercept maneuvering targets while simultaneously ensuring impact time and field-of-view (FOV) constraints without active speed control. The proposed technique utilizes a novel 3D nonlinear virtual relative model (NVRM) to describe the relative kinematics between the interceptor and target, with the model's origin attached to target's location. By applying optimal control theory, the guidance law is derived to eliminate the remaining trajectory error within the NVRM framework. Additionally, virtual FOV control is implemented in 3D space, ensuring the interceptor's FOV constraints are satisfied by leveraging the geometric relationship between the virtual and realistic FOVs. Theoretical analysis highlights the key features of the proposed guidance method. Numerical simulations are executed to substantiate its effectiveness and performance.