Unmanned Catamaran Motion Modeling And Autonomous Navigation Control Design

The motion modeling of the unmanned catamaran is the basis for stu dying the design of its autonomous navigation control.Through self-developed unmanned catamaran with twin propellers,the motion model is constructed based on the principle of course control by differential speed with twin propellers.Combining with the fuzzy PID control algorithm,the course controller and track point tracking algorithm are designed.And the track point tracking is realized by simulation design of the motion model.Meanwhile,a grid map is designed to realize obstacle detection based on lidar,and autonomous navigation is completed in the Xihu Lake.Both simulation and test results verify the accuracy of model design and the effectiveness of autonomous navigation control design.The hardware and software platform of catamaran is designed based on industrial personnel computer(IPC)and microcontroller.C# WinForm and MySql technology are adopted to design the host computer software,so as to realize multi-thread serial port communication between IPC and differential GPS,lidar and microcontroller to complete information storage.According to the control command issued by the upper computer software,the embedded controller controls the motor thruster by PWM wave to realize double-line motor drive control.The motion model of unmanned catamaran with twin propellers is constructed.First,based on motion analysis in the attached coordinate system and the inertial coordinate system,the motion model of the unmanned catamaran is constructed.Second,based on the principle of MMG modeling,a three-degree-of-freedom dynamic model for unmanned catamaran is constructed by analyzing the force acting on the catamaran under the action of twin propellers.Third,through the condition test of unmanned catamaran,its motion model is obtained by identifying part of the model parameters.And the simulation results are consistent with the experimental results,which verifies the validity of the model.The control algorithm is designed to realize track point tracking.Based on the analysis of the principle of course control for unmanned catamaran with twin propellers,the course PID controller and course fuzzy PID controller are designed.And the dynamic model of UAV is simulated considering the disturbance of wind and wave.Results show that the course fuzzy PID controller has better control effect.On this basis,the track point tracking algorithm is designed based on the indirect track tracking control,and the track point tracking is completed through the experiment in Xihu Lake.Grid map is constructed to realize obstacle detection.Through laser radar to sense the surrounding environment,TX2 acquires 3D point cloud data,projects 3D point cloud into 2D grid map,and uses threshold segmentation method to judge grid attributes to realize point cloud data prepr ocessing.Firstly,the threedimensional point cloud data are acquired by TX2 and the perception of the surrounding environment is obtained through lidar.The three-dimensional point cloud is projected into the two-dimensional grid map,and the point cloud data is preprocessed by using threshold segmentation method to judge the grid attributes.Second,based on OpenCV expansion and corrosion operator,the contours of obstacles are analyzed and extracted.Third,the unmanned catamaran makes corresponding actions to avoid obstacles according to the location information of obstacles.And finally,it realizes autonomous navigation through experiments in Xihu Lake.