Research And Design Of AUV Embedded Control System Based On ROS

Autonomous Underwater Vehicle(AUV)is an unmanned,autonomously navigated underwater vehicle.It integrates high-tech such as sensor technology and automatic control,and can be used to build underwater data collection systems,marine surveillance systems,and even underwater unmanned combat networks,are becoming increasingly important in scientific research and military fields.The electronic control system is the core of AUV and the concentrated expression of its high technology.AUV's environment perception,autonomous navigation,motion control,data acquisition,and special task execution all depend on the electronic control system.Current AUV electronic control system is bulky,high power consumption,and expensive.In view of its shortcomings such as not being able to work in narrow waters and high civilian costs,a ROS-based AUV embedded control system is designed.The system is mainly composed of navigation sensor system,Raspberry Pi master control,and STM32 auxiliary control board.ROS and Free RTOS was transplanted on the Raspberry Pi and auxiliary control board to develop the main control program and emergency strategy.The navigation sensors only uses an inertial measurement unit(IMU)and a depth sensor.The depth sensor is used to correct the gyroscope drift and cumulative error of integration operation,and more accurate spatial displacement data is obtained.Intuitive effects and parameter values of several data fusion algorithms are obtained by practical tests,and a fuzzy Kalman filter is selected as the data fusion algorithm of this design after comparison,which further reduces the effect of gyroscope drift.The calculation process of the algorithm has been improved,and its calculation amount has been reduced.Geomagnetic data was added when solving the AUV attitude,which effectively suppressed Z-axis drift and periodic zero-crossing.In order to adapt to the complex underwater hydrodynamic environment,a double closed-loop cascade PID control algorithm with an inner loop as the palstance and an outer loop as the attitude angle is used to complete the motion control of the AUV,which improves the anti-disturbance capability of the control system.The results of land debugging and water testing show that the embedded control system has realized the AUV's route along the preset,and the system has the basic navigation control and motion control capabilities.The system is based on an embedded controler and a streamlined sensor system.And the volume and power consumption are further reduced,the cost is lower.It can work in narrow waters and facilitate the expansion of AUV applications to the civilian sector,provides useful lessons for AUV miniaturization.