Ground Calibration Method For Improving UAV Target Location Accuracy

In modern warfare,drones are not only small,easy to hide,but also have high security,making them replace the large-scale manned reconnaissance plane as the most important investigation force on the battlefield front.Once the drone has locked a suspicious target,it can immediately and accurately attack the target.The above process is undoubtedly in line with modern military theory,that is,once the target is found and destroyed immediately.To ensure that drones can accurately target their targets,various onboard optoelectronic systems have been created.Based on the flight characteristics of drones,airborne electro-optical systems use a variety of sensors to capture reconnaissance ground targets and accurately identify them.Not only the measurement time is short,but also the positioning is very accurate.With the continuous development of modern science and technology,the performance of airborne optoelectronic systems has been greatly improved.It is not only more sensitive,but also has a higher recognition rate and a lighter volume,thus providing hardware protection for the precise positioning of drones.During the target positioning process,there is an error between the coordinate system of the inertial navigation system and the system where the optical axis of the optoelectronic system is located.As a result,the positioning accuracy cannot meet the requirements of the index.Only the calibration can resolve the geometric relationship between the two coordinate systems.The effect of the calibration will directly affect the target positioning accuracy of the drone.Therefore,the calibration of optoelectronic systems and inertial navigation systems is one of the first problems to be solved in the development of UAV target positioning technology,and it is a necessary prerequisite for achieving high-precision target positioning.This paper proposes a ground calibration method to improve the target positioning accuracy of airborne optoelectronic systems.The onboard optoelectronic system target positioning method refers to the optoelectronic system installed on the carrier,according to its own measurement values(target distance,azimuth/elevation angle)and the attitude angle of the aircraft,geographical coordinates,altitude(by the airborne inertial navigation system Given),calculate an algorithm for the coordinates of the air/ground point target it observes in the geodetic coordinate system.However,due to the error between the coordinate system of the inertial navigation system and the system where the optical axis of the optoelectronic system is located,the positioning accuracy cannot meet the requirements of the index.Two calibration methods are proposed in this paper,and their operation methods and algorithms are described.Target location field test,positioning accuracy of about 10 m to 40 m in the slope distance of 10 km.This method can use existing equipment,can be applied in various types of photovoltaic systems,and has strong applicability.