基于双目视觉的直升机旋翼桨叶挥舞角测量

为实现直升机旋翼桨叶挥舞角的测量,提出了一种基于双目视觉的测量方法.首先,在直升机旋翼桨叶上均匀布置编码标记点,用已标定的双目摄像机对旋翼桨叶每隔一定角度采集标记点图像;其次,对左右摄像机图像上的标记点进行解码和匹配,得到标记点的左右图像视差,进而计算标记点三维坐标;再次,利用标记点在各个角度下的三维坐标,计算旋翼中心和转轴方向,建立旋翼坐标系;最后,在旋翼坐标系下,根据标记点静止与高速旋转时在同一角度下的三维坐标,计算挥舞角大小.利用风扇叶片进行仿真试验,结果验证了该方法具有自动化程度高和测量精度高的特点,可满足直升机旋翼桨叶挥舞角测量的要求.

Flapping Angle Measurement of Helicopter Rotor Blade Based on Binocular Vision

In order to realize the measurement of flapping angle of helicopter rotor blade,a method based on binocular vision is proposed.Firstly,coded targets are set up uniformly on the helicopter rotor blade,and coded targets images are collected at every certain angle of rotor blade with a calibrated binocular camera.Secondly,the targets in images of left and right cameras are decoded and matched to obtain the parallax,and then the 3D coordinates of coded targets are calculated.Thirdly,the rotor center and direction of shaft are calculated according to the 3D coordinates of targets at different angles to establish the rotor coordinate system.Finally,the flapping angle is calculated in the rotor coordinate system according to the 3D coordinates of targets at the same angle in the conditions of stationary and rotating.The results of simulation tests carried out by using the electric fan blades show that this method has the advantages of high automation and high measurement precision,and can meet the requirements of helicopter rotor flapping angle measurement.