  This paper investigates an efficient algorithm for trajectory planning
problem of autonomous unmanned aerial vehicles which fly over three-dimensional
terrains. The proposed algorithm combines convex optimization with disjunctive
programming and receding horizon concept, which has many advantages, such as a
high computational speed. Disjunctive programming is applied in order to relax
the non-convex constraints of the problem. Moreover, the B-spline curves are
employed to represent the trajectories which should be generated in the
optimization process.
