Abstract Abstract China is a country with a broad sea.In our vast waters,there are many situations such as hydrology,Marine fishery resources,and coastal conditions need to monitor.In nowadays,when disasters or coastguard patrol and guard tasks appear,the very way we generally used for searching,rescuing and alerting are all but ships,aircrafts,or by using of satellites for monitoring.But this way is not only somehow expensive, inefficient,at the same time it's hard to complete the desired taskS in extreme conditions.Because of this,this paper designed a biomimetic seagull for ocean cruise monitoring use,and developed a prototype and a specialized flight testing system, which is used to test the key performance indicators. Based on the analysis of the task and the environment,the function of the biomimetic seagull and performance indicators were determined.Combining the flapping wing flight principle,the mechanical structure was designed.The structural principle is now a mature scheme which is often employed in the making of a flapping wing prototype.Through the symmetrical layout of the two sets of series link mechanism to implement complex flapping wing movement of four bar linkage,the set of institutions use only one degree of freedom,at the same time the structure of the wings in flapping symmetry can also ensure the motion is completely symmetrical. Compared with the fixed wing and rotorcraft flying robots,the seagull robot can at the same time produce the required lift and thrust in the process of a flapping circle,more efficient and with better mobility. Considering both the required performance parameters,and various components that can be purchased,the size of the mechanical structure of the whole system was determined and a prototype was made.In addition,the developed experimental apparatus for testing the seagulls of the rationality of the robot structure design,basic aerodynamic performance,and simulation of flight performance is also developed.The main role of the experiment device is to provide a rotary experimental platform,the structure mainly includes the support frame,turntable,the follow movement mechanism, and the parts for fixing and the installation of the seagull. By using the developed prototype,and the experimental devices,a set of experiments were conducted under the condition of specific parameters.The experimental results showed that the improved flapping wing mechanism is feasible, and it can achieve the flapping wing movement and lift and thrust required to produce in flight.Based on these experimental results,the direction for future improvement, including optimal design on the basis of the existing structure,further reduce the weight -I-Abstract - I - Abstract China is a country with a broad sea. In our vast waters, there are many situations such as hydrology, Marine fishery resources, and coastal conditions need to monitor. In nowadays, when disasters or coastguard patrol and guard tasks appear, the very way we generally used for searching, rescuing and alerting are all but ships, aircrafts, or by using of satellites for monitoring. But this way is not only somehow expensive, inefficient, at the same time it’s hard to complete the desired taskS in extreme conditions. Because of this, this paper designed a biomimetic seagull for ocean cruise monitoring use, and developed a prototype and a specialized flight testing system, which is used to test the key performance indicators. Based on the analysis of the task and the environment, the function of the biomimetic seagull and performance indicators were determined. Combining the flapping wing flight principle, the mechanical structure was designed. The structural principle is now a mature scheme which is often employed in the making of a flapping wing prototype. Through the symmetrical layout of the two sets of series link mechanism to implement complex flapping wing movement of four bar linkage, the set of institutions use only one degree of freedom, at the same time the structure of the wings in flapping symmetry can also ensure the motion is completely symmetrical. Compared with the fixed wing and rotorcraft flying robots, the seagull robot can at the same time produce the required lift and thrust in the process of a flapping circle, more efficient and with better mobility. Considering both the required performance parameters, and various components that can be purchased, the size of the mechanical structure of the whole system was determined and a prototype was made. In addition, the developed experimental apparatus for testing the seagulls of the rationality of the robot structure design, basic aerodynamic performance, and simulation of flight performance is also developed. The main role of the experiment device is to provide a rotary experimental platform, the structure mainly includes the support frame, turntable, the follow movement mechanism, and the parts for fixing and the installation of the seagull. By using the developed prototype, and the experimental devices, a set of experiments were conducted under the condition of specific parameters. The experimental results showed that the improved flapping wing mechanism is feasible, and it can achieve the flapping wing movement and lift and thrust required to produce in flight. Based on these experimental results, the direction for future improvement, including optimal design on the basis of the existing structure, further reduce the weight