A simple and adaptive on-line path planning system for a UAV

Design of Three-Dimensional Path Following Guidance Logic

“…In this way, the positioning method of the virtual target maintains consistency with the straight-line path case. Furthermore, this positioning method is very simple and practical compared to the previous methods in which the target is positioned at a point on the circular path, which is usually selected as an intersection point of the circular path and the reference distance from the vehicle [9][10][11].…”

“…Global convergence is proved, but this method is not applicable to three-dimensional space paths. Recent common approach [7][8][9][10][11][12][13] is rewriting the path following problem as the classical line-of-sight guidance problem by specifying a moving virtual target along the desired path. This approach generates a simple guidance law, yet can compensate a large deviation from the desired path.…”

“…However, the position of virtual target is not easy to determine, and the initial distance between the vehicle and the desired path should be less than the specified distance. Some methods in this approach are still for the paths in planar motion [9][10][11][12][13].…”

“…The proposed guidance logic is equally applicable to two primitive path types in three-dimensional space: straight-line path and circular path, and might be extendable to any smooth path. Similar to the methods in [7][8][9][10][11][12][13], the proposed guidance logic also uses a moving virtual target on the desired path; however, the proposed logic explicitly specifies the motion of virtual target by introducing the concept of the projection point and the tangentially receding distance. The proposed logic is simple and efficient, yet provides precise path following.…”

Design and implementation of a leader-follower cooperative control system for unmanned helicopters

“…As we know, a single UAV has its limitation problem for trajectory tracking, that is, an UAV cannot follow a high dynamic trajectory (see, for example, [13]). For example, when an UAV is to track a circular path (see Fig.4), the lateral movement is determined by…”