A Study Of UAV Path Planning Algorithms

With the rapid development of UAV control,the production and planning of UAV tracks have become a hot spot of technological research into the UAV studies.The UAV flight path planning is a method which can plan a satisfactory flight track based on consideration of all kinds of factors and is one of the key technologies for drone applications.Therefore,it is very important to do research into the UAV path planning algorithm.In this paper,flight path planning methods for single UAV and Multiple are respectively studied with the usage of PH curve algorithm for initial and final speed directions are not considered in traditional track planning and too much unnecessary space search and unsmooth flight path are existed when random points are selected by the traditional RRT algorithm.The main research work and innovations are as follows:1.First,in this paper the method of the UAV flight path planning is studied based on the Pythagorean Hodograph(PH)curve,and then a kind of UAV flight path planning method is proposed based on the combination of improved Pythagorean Hodograph(PH)curve and RRT(Rapidly-exploring Random Tree)algorithm.In the case of multiple obstacles,the angle of the inflection point of the classical PH curve is defined separately and in the offline planning,the control points b2 and b3 are set as the new starting point start1 and the new ending point goal1.Finally,the best flight path of track set which is calculate d by RRT algorithm rule is picked out as the final algorith.2.For there are too many unnecessary space search problems when selecting random points with the traditional RRT(Rapidly-exploring Random Tree),in this paper,a new random search space route value and a threat value are set in the RRT(Rapidly-exploring Random Tree)algorithm.And then multi-UAVs' collaborative flight path planning is achieved with improvement of combined with the improved of Pythagorean Hodograph(PH)curve method and the usage of the smoothing operator and sliding window filtering track-smoothing processing method.3.In response to the multi-UAVs' cooperating tasks and the impact of sudden threats on multi-UAVa collaborative track planning,the man-machine flight speed is coordinated by consensus to achieve the requirements for multiple drones to work together because of theapplication of artificial potential field method to achieve real-time flight path planning of drones.The simulation results show that the initial and final velocity directions are considered with the new algorithm combination of the improved RRT algorithm and improved PH curve algorithm.Besides,the new algorithm which can shorten the course trajectory,successfully avoids obstacles,and ultimately completes the planning of the drone track.Therefore,to some extent the research results of this paper have reference value for drone track planning.