An integrated navigation method based on an adaptive federal kalman filter for a rice transplanter

In this article, an integrated global positioning system (GPS), inertial navigation system (INS), and visual navigation system (VNS) navigationmethod based on an adaptive federal Kalman filter (KF) is presented to improve positioning accuracy for a rice transplanter operating in a paddy field. Theproposed method used GPS/VNS to aid the INS and reduce the influence of the accumulated error of the INS on navigation accuracy. An adaptive federal KFalgorithm was designed to fuse navigation information from different sensors. The information distribution factor of each local filter was obtained adaptivelyon the basis of its own error covariance matrix. Computer simulation and transplanter tests were conducted to verify the proposed method. Results showedthat the proposed method provided accurate and reliable navigation information outputs and achieved better navigation performance compared with singleGPS navigation and an integrated method based on a conventional federal KF.