The Research Of UAV Attitude Measurement System Based On Polarization

Navigation system is an important part of the UAV control system.There are various kinds of navigation with the development of the technology.However,existing navigation methods have their own strengths and weaknesses and applied to different environments.To improve the accuracy and robustness,except for improving the manufacturing level of the navigation sensors,learning the new methods of navigation is also important research.Using the polarized information to navigation is a research hotspot at home and abroad in recent years,and it has the advantages of anti electromagnetic interference and good concealment.The content of this paper is researching the integrated navigation between polarization and the SINS to attitude estimation of the UAV.The main works of this paper as follow:The article explains the concepts of navigation and derives the theory of the SINS.Conduct the simulation experiments using the Matlab based on high precision of inertia measurement unit(IMU)which can be used to location and low precision of the IMU which made of the MEMS.We can get the conclusions of the navigation error of the SINS is accumulating as the time because of the theory of the SINS and the low precision IMU made of the MEMS can be used to attitude estimation only.To meet the requirement of polarization sensor experiment,build the experiment platform based on polarization sensor.The experiment platform is based on the open source project named Paparazzi because of its good feature of extending.This paper analysis the experiment platform form hardware and software.What's more,auto flight experiments and the experiment of polarization data collected onboard were conducted.Through the succeed auto flight experiments we can get the conclusion that the output of the autopilots is accuracy and can be used as reference in the algorithm designed.Come up with the quaternion complementary filter algorithm based on polarization sensor.First of all,deduce and prove the theory of the complementary filter.And then apply the theory to gyros and accelerators,the IMU and polarization sensor.Compensate the gyro's error of XY axis and Z axis.The algorithm designed can get the accuracy attitude angle through the proving of the experiments at the quasi static state.Come up with the complementary filter algorithm of compensating the motion acceleration.There is a limit of quaternion complementary filter algorithm based on polarization sensor;the motion acceleration of the UAV has to be zero.Optimize the algorithm through adding the airspeed meter and redesign the structure of the complementary filter to compensate the centripetal acceleration.Contrast of output of the attitude estimation of the algorithm designed before and the optimized algorithm through simulation experiments.The conclusion of the experiments shows the good quality of the optimized algorithm in flat turn.