Design and Implementation of Vehicle-Mounted Dual-Axis Solar Tracking System

To assist the Fourier transform infrared (FTIR) spectrometer to be able to measure the total amount of atmospheric greenhouse gas columns on a mobile platform, a vehicle-mounted dual-axis solar tracking system is studied and designed. A tracking strategy using a combination of coarse and fine tracking is proposed to address the problem of tracking accuracy degradation caused by vehicle turning and changing direction, the existence of slopes on the road surface, and the sunlight being blocked by objects. The vehicle steering angle is measured using an attitude sensor, and the solar position algorithm is used to calculate the azimuth and altitude angle changes of the sun and drive the motor to complete the coarse tracking process. The CMOS image sensor is used to capture the spot image, and then the image processing algorithm is used to calculate the center-of-mass coordinates of the spot, and the motor is fine-tuned to reduce the pixel distance between the center-of-mass of the spot and the center of the image to improve the tracking accuracy of the system. The experimental results show that the solar tracking system has the advantages of fast target retrieval after the vehicle turns and accurate tracking even if the sunlight is blocked by objects, and the length of the road section with light spots in the field of view accounts for about 92.8% of the total distance.