Design of large FOV high precision three-dimensional attitude angle measurement system

Based on pinhole imaging and TRIAD principles, a new method of large FOV (field of view) high precision three-dimensional attitude angle measurement was designed using a single CMOS image sensor. The dual parallel collimation light source is designed according to the demand of the measurement system. A single FPGA is used to implement image sensor imaging, spot segmentation, spot centroid positioning and rapid communication with the USB. The direction vectors of two parallel collimation beams are calculated according to the centroid coordinates of the spots. The rotation matrix of the attitude sensor is calculated based on TRIAD theory and the 3D attitude angle is obtained. According to the pinhole imaging model, the internal and external parameter united calibration model of the attitude sensor is established, and the measurement system is calibrated. Calibration and experiment measurement results show that the field of view of the 3D attitude angle measuring system is 19.6° × 19.6° and the precisions of the pitch, yaw and roll angles of the measurement system are 9.9″, 9.3″ and 80.2″, respectively.