The Key Technology Research Of Unmanned Surface Vehicle

Unmanned surface vehicles(USV) are vehicles that operate on the surface of water without people. They are mainly used in the military field early, which can replace the human to complete some operational tasks, such as maintenance of maritime and port security, anti-terrorism protection, anti-mine and anti-submarine. Later, they are gradually widely used in a variety of civilian areas, including exploration of the Antarctic ice shelf, checking underwater oil and gas pipelines, to investigate the effects of the oil spill, deep-sea photographic survey, subsea facilities maintenance, oceanographic research. With the rapid development of computer technology, navigation control technology and electronic technology, a number of technical problems in USV are solved increasingly and now USV has become a hot topic at home and abroad. This paper is to design a completely independent, low cost, high precision unmanned boat for environmental monitoring, reducing the risk factors of staff, improving the efficiency of the water sector and related industries.Firstly, according to the design requirements in the field of water measurement, we present a complete system solution, including design of ground station system and shipboard system. This paper introduces the hardware design of USV, including the selection of the core processor, attitude sensors, GPS receivers and other equipments. Select the embedded Linux operating system as the software platform for USV. All the algorithms and procedures are based on the Linux platform.Secondly, the focus of this paper’s research is to design USV’s navigation system. In order to obtain the USV’s attitude information, read raw data of gyroscope, accelerometer and magnetometer, then obtain attitude information with discrete Kalman filter algorithm based on Euler angle and extended Kalman filter algorithm based on quaternion. Experimental results show that the extended Kalman filter algorithm based on quaternion has a better effect. When USV is stationary, the second algorithm’s convergence rate is faster and can get all-attitude easily. In order to obtain USV’s position information and speed, this paper parses GPS data from the GPS receiver to get them.Then, this paper introduces the USV’s communication system design. The communication system uses Wi-Fi. The UDP transport protocol is used between the ground station and USV. MAVLink protocol is used as application layer protocol. This paper introduces the communication interface between core processor and other equipments, including serial communication and I2C communication, and how to program in Linux platform.Finally, this paper introduces the entire software system design of USV, including hardware abstraction layer, module layer and configuration layer, which is divided into different tasks using Linux multithread technology, including communication task, attitude task, GPS task, control task. Develop the ground station software for test with c# and launch experiments to verify the feasibility of the whole system.