旋翼无人机测算风速风向技术研究

Research on measuring wind speed and direction of rotor UAV

目前大部分民用无人机没有准确测量风速、风向和预警风场的功能,然而森林火灾扑救等多种场景需要无人机可以提供准确的风速。本文提出了一种基于旋翼无人机坐标数据测算风速风向的技术,通过无人机主机RTK坐标信息及方位角、倾角数据精准获取螺旋桨点相对坐标信息,选择不同负载条件下无人机以1~16 m/s的不同速度分别飞行30 s以上,根据螺旋桨坐标信息变化数值,结合风洞测试数据及风场动力学原理,研究风速与旋翼无人机倾角关系,并通过风洞试验检验该方法精度;并可根据无人机RTK推算出的螺旋桨坐标变化信息判断风向。结果表明,无人机风速与旋翼无人机倾角呈正相关关系;无人机负载加重时,对应受风速干扰的倾角会相对减小;无人机飞行受阵风干扰出现噪点的概率,高海拔区域大于低海拔区域;并建立六旋翼无人机飞行倾角的风速估算模型y=-1.0435+1.1501x,该模型测算风速的中误差值为0.966,绝对值小于1,满足应急指挥现场对无人机测量风速精度要求。该方法得到风速测算精度高,可以为旋翼无人机实时获取风速风向提供一种可行方法,具有一定的实用价值。

At present,most civil UAVs do not accurately measure wind speed,wind direction and early warning wind field.However,forest fire fighting and other scenarios require them to provide accurate wind speed.In this paper,a wind speed and wind direction measuring technology based on the coordinate data of the rotor UAV is proposed.The relative coordinate information of the propeller point is accurately obtained by the RTK(real time kinematic)coordinate information and the azimuth and inclination data.The rotor UAV with different carriers is flying at different speeds of 1 m/s to 16 m/s for more than 30 seconds.According to the change value of the propeller coordinate information,combined with the wind tunnel test data and the wind field dynamics principle,the relationship between the wind speed and the azimuth is studied.The accuracy of the method is tested by wind tunnel experiments.The wind direction can be judged based on the propeller coordinate change information calculated by the RTK.The results show that the wind speed is positively correlated with the azimuth.When the carriers is increased,the azimuth corresponding to the wind speed disturbance would be relatively reduced.The probability of the UAV flight being affected by the gust disturbance,the high altitude area is larger than the low altitude area,and the wind speed estimation model of the flying angle of the six-rotor UAV is established,y=-1.0435+1.1501x,the median error value of wind speed measured by this model is 0.966,and the absolute value is less than 1,which meets the requirement of wind speed measurement accuracy of UAV on the scene of emergency command.The method had high accuracy of wind speed measurement,and could provide a feasible method for real-time wind speed and direction measurement of the rotor UAV which had certain practical value.