UAV Trajectory Planning in a Port Environment

Gang Tang,Christophe Claramunt,Xiong Hu,Zhipeng Hou

doi:10.3390/jmse8080592

Abstract

In many situations, the trajectory of an unmanned aerial vehicle (UAV) is very likely to deviate from the initial path generated by a path planning algorithm. This is in fact due to the existence of dynamic constraints of the UAV. In order to reduce the degree of such a deviation, this research introduces a trajectory planning algorithm, the objective of which is to minimize distance while maintaining security. The algorithm first develops preprocess trajectory points by constructing isosceles triangles then, on the basis of a minimum snap trajectory method, it applies a corridor constraint to an optimization objective function, while the deviation evaluation function is established to quantitatively evaluate the deviation distance. A series of experiments were carried out in a simulation environment with a simplified quay crane model. The results show that the proposed method not only optimizes the time and length of the generated trajectory, but also reduces the average deviation distance by 88.7%. Moreover, the generated trajectory can be well tracked by the UAV through qualitative and quantitative analysis. Overall, the experiments show that the proposed method can generate a higher UAV trajectory quality.

Highlights

A port environment is a relatively self-executing and complex transportation system, in which the role of the quay crane is to achieve the efficient transportation of goods between land and sea [1]
In many situations, the trajectory of an unmanned aerial vehicle (UAV) is very likely to deviate from the initial path generated by a path planning algorithm
The algorithm first develops preprocess trajectory points by constructing isosceles triangles on the basis of a minimum snap trajectory method, it applies a corridor constraint to an optimization objective function, while the deviation evaluation function is established to quantitatively evaluate the deviation distance

Summary

Introduction

A port environment is a relatively self-executing and complex transportation system, in which the role of the quay crane is to achieve the efficient transportation of goods between land and sea [1]. Due to frequent operations of the quay crane, a series of damages, such as cracks and rust, may affect the service life of the machinery. A quay crane should be maintained regularly and properly. Maintenance operations and inspections are carried out by specialized personnel on the quay crane, which is time-consuming and laborious work. This requires frequent long-term shutdowns of the equipment, and generates unforeseen dangers to the workers [2]. The purpose of a UAV trajectory planning is to quickly generate a collision-free trajectory from the starting position to the goal position under some given constraints

Methods

Results

Conclusion