Three-dimensional waypoint following for fixed-wing unmanned aerial vehicles in obstacle-filled environments

Abstract

The paper computes optimal paths for fixed-wing unmanned aerial vehicles with bounded turn radii to follow a series of waypoints with specified directions in a three-dimensional obstacle-filled environment. In the existing literature, it was proved that the optimal path is of circular turn–straight line–circular turn (CSC) type for two consecutive waypoint configurations, when the points are sufficiently far apart and there is no obstacle in the field. The maximum of all minimum turn radii corresponding to all possible two-dimensional circular maneuvers was used for both the initial and final turns to develop the CSC-type paths. But, this paper considers the minimum turn radii for initial and final turns, corresponding to the maneuvering planes and which produces shorter CSC-type paths. In an obstacle-filled environment the shortest path may collide with obstacles, so a strategy is proposed to switch to the next best path that does not collide with obstacles. Using this technique, a series of waypoints is followed in the presence of obstacles of different types, for example, cylindrical, hemispherical, and spherical in shapes with different sizes. Finally, simulation results are presented to show the efficiency of the algorithm for obstacle avoidance. The computation time listed here indicates the potentiality of this algorithm for implementation in real time.

Time-optimal moving target interception with impact angle constraint

“…Earlier, a PN based guidance law was proposed in Ref. [29] for stationary target interception in 3D space. But in this work, the target is considered as moving, which implies that the final point of the Sussmann’s problem is not fixed, so the optimal path generation is more challenging.…”

“…The extension of the work 28 was presented in Ref. [29] by considering the different values of turn radii for different inclined planes in 3D space, so the generated path of Ref. [29] is shorter than Refs.…”

Rotate artificial potential field algorithm toward 3D real-time path planning for unmanned aerial vehicle

“…Moreover, most of the existing path planning algorithms are aimed at large-scale fixed-wing UAVs, which have been developed in recent years. 10,26 When the same algorithm is applied to small UAVs represented by multi-rotor UAVs, it is difficult to implement because of hardware conditions and other limitations. Although the APF as dynamic planning can solve the above problems by collecting and updating information in real-time.…”

“…In practical applications, the APF often produces obstacle avoidance trajectories with too large an angle. 27 Moreover, most of the current APFs treat obstacles as simple geometries such as masses or spheres when performing simulations, 26 and the scene setup is also relatively simple, 28 lacking application value. As the operation area of UAVs is mostly in large scenes, the APF as a local path planning algorithm often yields unsatisfactory results.…”

Robust nonlinear guidance strategies for survival of cooperating unmanned aerial vehicles against pursuing attackers

“…In literature, various nonlinear control techniques were used in aerospace applications such as target interception at desired impact time, 24 impact angle constraints, 25 impact time and impact angle constraints, 26,27 integrated guidance and control, 28 waypoint following for fixed-wing UAVs, 29 flat-spin aircraft recovery, 30 and salvo guidance. 31,32 Most of the guidance discussed so far were designed with the objective of minimizing a performance index using the optimal control design framework.…”