Three-Dimensional Autonomous Guidance for Enclosing a Stationary Target Within Arbitrary Smooth Geometrical Shapes

This article presents a target-enclosing guidance law for an autonomous vehicle to enclose a stationary target within arbitrary smooth geometrical shapes or patterns in 3-D, thereby presenting a generic guidance strategy for target-enclosing behavior. We particularly focus on designing a target-enclosing strategy wherein the vehicle does not have radial acceleration capabilities and is steered by its lateral acceleration only. Such consideration makes the design appealing for aerial vehicles with turning constraints. The proposed design accounts for the coupled 3-D engagement, thereby preventing performance degradation when the pitch and the yaw channels are decoupled into two separate and mutually orthogonal planar engagements. We further evaluate the lateral acceleration components of the vehicle in the orthogonal (pitch and yaw) channels by minimizing the instantaneous total control effort subject to an affine constraint. We demonstrate the effectiveness and advantages of the proposed controller through simulations.