The Design Methods Research Of Helicopter Flight Quality

With the deep comprehending and studying of ADS-33, many scientists focus their investigations on designing by standard and achieving flight quality level.Helicopters have bad flight qualities because of its own characteristic. Improving helicopter flight qualities by design is the aim of research work. It is very difficult to implement high qualities only depending upon the aerodynamic configuration or stucture design. It is the important development to adopt the flight control system to improve flight qualities, and control law design plays an important role in helicopter flight quality design.In order to contact close with requirements in ADS-33, Model-Following is chosen firstly in the process of flight control system design. At the time of ideal model design, requirements in ADS-33 are introduced to flight control system, and they are always the design standard. Then, entire frame and structure of flight control system is constructed by use of Model-Following, and the position of three control matrixs in system and their relationship are found. In consequence of helicopters' own characteristic, it's difficult to achieve perfect following to ideal model, this research work uses Eigenstructrue Assignment to optimize in mathematics, and calculates three control matrixs in Model-Following and has a great mathematical effect. But the optimal work in mathematics isn't equal to this in practice. At the end of design, the paper focuses on adjusting the result according to helicopters' connatural characteristic.By simulating to system with control, and checking out the correlative items and requirements in ADS-33, it is proved that the flight qualities of sample helicopter have improved largely and achieved these requirements in ADS-33.At the same time, it illustrates the rationality of design strategy and the validity of control system.