Research On Multi-AUV Cooperative Navigation And Positioning Method

Nowadays,whether autonomous underwater vehicles are used in military reconnaissance and surveillance,anti-submarine and patrol,resource detection,oil exploration,diving support and other fields,underwater unmanned vehicles are small in size,low in cost,and can navigate autonomously and can replace humans.Perform tasks in complex and dangerous areas.With the diversification and complexity of underwater tasks,if only a single AUV cannot achieve the required requirements of the task,GPS information cannot be obtained continuously,there is no mother ship tracking,and there is no way to obtain location information with terrain matching.Through data sharing and exchange between AUVs,the accuracy of each AUV will be compensated to a certain extent or will be temporarily supported by data when a certain AUV loses its navigation ability.The main work of the thesis is as follows:First of all,it is necessary to establish a coordinate system based on the single pilot coordinated navigation system,and establish the corresponding following AUV mathematical model for the single pilot coordinated navigation.At the same time,use the extended Kalman filter and the unscented Kalman filter algorithm to simulate the effect of the model.The result shows that the position after the unscented Kalman filtering algorithm is closer to the real position,and the filtering effect is better.Secondly,due to the specificity of AUV’s own dead reckoning,navigation equipment and underwater environment,certain errors will inevitably occur,such as errors caused by the navigation device of the AUV equipment itself,the delay of acoustic communication and ranging,and the coordinated navigation of the AUV Analyze the various errors that may appear in the navigation sensor,and design the filter for the error generated by the navigation sensor.The various device errors of the navigation sensor are used as the state quantity,and the difference between the inertial navigation device and the state quantity such as speed,position and attitude.The value is used as the measured value,and the simulation is carried out with the EKF and UKF algorithms.The simulation results show that the filtering effect of the UKF algorithm on the position,velocity and attitude errors is significantly improved than the EKF effect.Finally,analyze the influence of inertial navigation on collaborative navigation,and compare and analyze the pilot AUV plus inertial navigation device and without inertial navigation device,and simulate the navigation trajectory following the AUV,through the real water point and filter measured by GPS The latter water outlet points are compared and simulated to verify the effect of the inertial navigation device on the performance of the multiAUV collaborative navigation system,and to verify the impact of different filters on the navigation accuracy.The lake test experiment and simulation results show the filtering effect of the adaptive Kalman filter.Compared with EKF and UKF algorithm,the filtering effect is better.