Relative Attitude Estimation Approach Based on Correlated Frames Using Planar Target

A three-dimensional (3D) attitude measurement approach for planar target based on correlated frames is proposed to solve the problem of low off-plane angle measurement accuracy for 3D relative attitude estimation using planar target as cooperative target. First, the target attitude of each frame of image is calculated by attitude estimation approach by a single-frame image. Second, the high-precision angle information provided by the fiber-optic gyro unit is used to realize the correlation of adjacent frames of target images. Finally, the 3D attitude of planar target is estimated by superimposing multiple frames of correlated images. This approach makes full use of the high-accuracy of short-time attitude of the fiber-optic gyro unit, and reduces the influence of image random noise on attitude measurement by correlating sequence image. Simulation and experimental results show that when the relative attitude angle varies from −2° to 2°, the proposed approach improves the measurement accuracy of the off-plane angle by a factor of 6 compared with the traditional ones.