Development Of Ship True Wind Observation System Based On Attitude Sensor

The accuracy of sea surface wind direction and wind speed data largely determines the safety of the ship’s navigation process,and it is also the basis of all kinds of marine operations,which is of great significance for meteorological observation,ship maneuvering,disaster prevention and so on.But usually,in the process of wind measurement,the errors caused by the spatial movement and navigation caused by the sway of the ship itself will result in the inaccuracy of the final real wind speed and wind direction data measurement.In order to solve the problem that the existing volunteer ship true wind measurement is not accurate enough,this thesis studies the ship motion compensation method and the ship true wind measurement method,and puts forward a true wind observation system for ship motion compensation based on attitude sensor.The specific contents are as follows:Firstly,the vector calculation of relative wind,navigation wind and true wind and the attitude compensation algorithm of ship motion based on rotation matrix are analyzed.It is concluded that the factors affecting true wind measurement mainly include wind direction,wind speed,speed,course,roll Angle,pitch Angle and yaw Angle.The function of the system is analyzed,including the collection of basic data related to true wind and the processing of the collected basic data.On this basis,the framework of the observation system is determined,which is divided into two parts: outside and inside: STM32 single chip microcomputer as the main control core,RT-Thread domestic real-time operating system as the basis,supplemented by a variety of acquisition sensors outside the cabin part,and equipped with the ship’s true wind observation system data reception and processing functions of the upper computer in the cabin part.Secondly,related hardware selection and circuit design are carried out to meet the needs of data collection for true wind calculation.The three-dimensional wind speed and direction sensor WindMaster is used to measure the real-time wind speed and direction.The six-axis attitude sensor MPU6050 extended magnetometer and GPS are used to measure the changes of the space attitude Angle and the ship’s speed and heading during the voyage,and the circuit part of each device is designed reasonably.In order to realize better data transmission,LORA module is used for data packaging transmission through the protocol.Then,in order to collect the corresponding data in real time and complete the transmission so as to further solve the true wind,the upper computer software and ship true wind observation system software based on RT-Thread are designed and written.For the ship’s true wind observation system,initialization and hardware driving design should be carried out at the hardware level.Configure thread priority and time slice to realize real-time synchronization between multithreaded tasks;The design of the upper computer in the cabin should have the functions of wireless data receiving and unpacking,real-time display,true wind calculation and curve comparison.Finally,the system function test,real wind simulation experiment and field experiment of ship real wind observation system are carried out.Functional testing ensures the normal operation of the ship’s true wind observation system,stable wireless communication and accurate data acquisition by each sensor.The accuracy and reliability of the vector calculation of ship relative wind,navigation wind and true wind and the ship motion attitude compensation algorithm based on rotation matrix are verified by the simulation experiments of true wind.The field experiments were carried out on the Marine experimental station and on the real ship respectively.The experimental results show that the relatively accurate wind speed and direction data are obtained in the field experiments,and the influence of ship motion on the true wind observation is improved to a certain extent.