Research And Design Of Scanning Servo Device For Airborne Microwave Radiometer

Microwave Remote Sensing is a cutting-edge technology which has great influence with our daily life,it can be used in so many important fields such as weather forecasting,environmental monitoring,or agriculture researching.Microwave Radiometer is an important device that used in Microwave Remote Sensing,it has been the focus of scientists from all over the world since it was invented,it can be carried on the ground platforms,satellites,and airplanes,to carry out the observation missions towards various targets including ground,sea,air and space.Compared with other carrying platforms,the remote sensing aircraft has several outstanding advantages such as stronger mobility and larger capacity,and that makes the Airborne Microwave Radiometer become one of the top priority in the study of Microwave Remote Sensing technology.In this paper,which is based on one of the Major National Science and Technology Infrastructure Projects-"Airborne Aviation Remote Sensing System”,with the background of Airborne Microwave Radiometer,the research and design work of scanning servo device for Airborne Microwave Radiometer had been done.According to the requirements of the project,the mechanical structure and the servo control system of the scanning servo device had been designed,by using computer analytical tools,the statics and dynamics simulation analysis of mechanical structure had also been finished,as well as the simulation of servo control system.The purpose of this paper is to design a scanning servo device for Airborne Microwave Radiometer,the mechanical structure is strong enough to meet the requirements of the airborne working environment,and the control system can perform high precision of speed control.This paper mainly completes the following research work:(1)The characteristics and application fields of the Microwave Radiometer had been introduced,the development history and the research status as well as the structure characteristics of typical products of the Microwave Radiometer at home and abroad had been summarized,especially the Airborne Microwave Radiometer.In addition,the significance and the main research tasks of this article was expounded.(2)The design criterions of the scanning servo device for the Airborne Microwave Radiometer was expounded,according to the design specifications,the whole layout of the structure had been decided,and the design of the mechanical structure had been completed,as well as the calculation and selection of key parts,such as motor and sensors.(3)All kinds of bad working conditions of airborne equipment were introduced,by using the finite element analysis software,the stress state of the scanning servo device while its under extreme conditions were simulated,and according to the relevant industry standards for designing airborne external equipment,the modal analysis and random vibration analysis of the device had also been done.(4)The requirements of scanning servo system in the Airborne Microwave Radiometer and the typical structure of servo control system had been described.According to the principle of dc motor speed control system and the mechanism modeling method,the mathematical model of dc torque motor was established.This paper discussed the dc servo motor speed control system of the current-speed dual closed-loop control system and figured out the dynamic structure diagram of control system with the help of the mathematical model of dc torque motor.(5)The current loop and speed loop of the dual closed loop speed control system had been designed,and the current loop controller and speed loop controller were corrected by combining with PID control algorithm.By using simulation software,the dual closed loop control system was analyzed,which had been corrected.The change of current and speed during the starting process of the dc motor was Simulated,the antijamming performance of the speed control system was also tested.In this paper,the design of scanning servo device for Airborne Microwave Radiometer meets all requirements,the research results for scanning servo system laid a solid foundation for the practical application of airborne remote sensing,also provides a certain reference for the development of similar equipment.