A Bearings-Only Trajectory Shaping Guidance Law With Look-Angle Constraint

This paper addresses the problem of achieving a desired impact angle against a stationary target with seeker's field-of-view limits. A bearings-only information based guidance law is investigated as a prospective solution. Analyzing the look-angle and the line-of-sight angle relationship, closed-form expressions of the guidance gains are derived for the desired impact angle and maximum look-angle constraints. A detailed analysis is carried out for lateral acceleration boundedness resulting in a design solution expressed in impact angle-maximum look angle space. Validating the guidance law, numerical simulations are performed using a kinematic vehicle model and a realistic model with given thrust and aerodynamic characteristics. Overall, the work offers an easily implementable guidance method with simple structure and closed-form guidance gains.