Controller for UAV to Oppose Different Kinds of Wind in the Environment

Bohang Wang,Zain Anwar Ali,Daobo Wang

doi:10.1155/2020/5708970

Abstract

Small UAVs are susceptible to the external disturbance, especially the wind field disturbance in the atmosphere environment. As a result, UAV’s states including attitude, speed, and position are usually unable to track the desired control commands. In this paper, different types of wind fields which easily affect the UAV are summarized; furthermore, the mechanism of their wind fields affecting the UAV is first strictly analyzed. Next, a novel “reject external disturbance” flight mode for UAV is put forward to offset the trajectory deviation caused by side wind, which makes use of the wind speed information obtained by airspeed and ground speed of UAV. In order to implement the “reject external disturbance” flight mode, the Lyapunov stability theory-based variable model reference adaptive control (VMRAC) system is proposed, and it could also deal with the adverse effects of wind shear and turbulence on UAV flight. Finally, simulation results show that the proposed strategy can significantly improve the trajectory following quality of the UAV under wind disturbance.

Highlights

Unmanned aerial vehicles (UAVs) are extensively used in the recent years. e civilian UAVs are commonly used for insecticide spraying, atmospheric observation, etc, whereas the military UAVs are used for targeting, communication, etc. [1].e extensive attention towards small UAVs has been increased due to small size, low cost, and flexibility. e takeoff weight of small UAV weight is under 200 kg, speed is generally less than 100 km/h, and the wingspan is no more than 5 m [1].e control of UAV is difficult due to the disturbance of atmospheric environment
E extensive attention towards small UAVs has been increased due to small size, low cost, and flexibility. e takeoff weight of small UAV weight is under 200 kg, speed is generally less than 100 km/h, and the wingspan is no more than 5 m [1]
E purpose of the “reject external disturbance” flight mode is to enable the UAV control system to achieve this operation in place of the ground control station

Summary

Introduction

Unmanned aerial vehicles (UAVs) are extensively used in the recent years. e civilian UAVs are commonly used for insecticide spraying, atmospheric observation, etc, whereas the military UAVs are used for targeting, communication, etc. [1]. E control of UAV is difficult due to the disturbance of atmospheric environment It affects the safety of flight as well. E purpose of the “reject external disturbance” flight mode is to enable the UAV control system to achieve this operation in place of the ground control station. (1) Summarizes the characteristics, types, and mathematical model of the environmental wind which is met by UAV in low-altitude environments Based on these information, the paper first rigorously analyzes the mechanism of various types of wind that affects UAV’s speed, attitude, and position and clarifies the relationship between wind speed, airspeed, and ground speed; it will provide reference to other researches in the relative areas. (2) According to the contribution (1), a novel “reject external disturbance” flight mode is proposed to solve the problem of trajectory deviation caused by side wind. (3) e variable adaptive control system is designed to implement “reject external disturbance” flight mode and deal with input disturbance caused by turbulence

Types of Wind in the Atmosphere

Control Strategy for Eliminating the Adverse Effects of Wind

Simulation Experiment

Conclusion