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直升机神经网络控制与飞行品质要求的实现
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摘要
最新的航空设计标准把飞行品质作为主要设计指标之一。
     直升机的固有特点使其飞行品质较差,但其使用任务却要求它具有良好的飞行
    品质。单纯依靠结构设计、气动布局已难实现高品质的要求。采用飞行控制系统改
    善飞行品质是重要发展方向,控制律的设计是直升机飞行品质设计的重要内容。
     根据飞行品质规范确定飞控系统的性能要求、在飞控系统中直接实现规范要
    求,是目前直升机飞行控制技术研究的热点之一。传统的飞控系统设计技术很难满
    足品质设计的要求。
     为了给型号研制中飞行品质的规划、分析和评价提供基本的、有效的工程实用
    工具,本课题在充分消化理解美军新航标ADS-33的基础上,作了以下工作:
     (1)针对具体直升机,从任务分析入手,根据规范要求确定对飞控系统的要求;
     (2)应用自适应神经网络模型逆控制技术,构造了能够满足飞行品质要求的直
     升机姿态控制器,实现了两种响应型式、两种控制模式,并根据ADS-33
     进行了定量指标评估;
     (3)在姿态控制器的基础上,构造了轨迹跟踪器,进行了任务科目基元仿真和
     飞行品质评估。
     通过该课题的研究,得到以下结论:
     (1)参考模型跟踪结构能够直接实现飞行品质规范要求,可以用于直升机飞行
     品质设计;
     (2) 自适应模型逆控制方法只需一个基准状态下的近似线性模型,却可在整个
     使用包线内提供协调一致的飞行品质;
     (3)自适应神经网络模型逆控制技术可节约成本,缩短飞控系统研制周期;
     (4) 在某些部件部分意外失效或战损情况下,自适应神经网络具有实现控制的
     在线快速重新配置、保持飞行品质的潜力;
     (5)轨迹跟踪控制器可以用于任务科目基元仿真及飞行品质评估。
Handling Quality is one of the principal design requirements in the up-to-date Aeronautical Design Standard (ADS).
    Helicopters have worse handling quality than the fixed-wing aircrafts because of their natural features, but the excellent quality is required by their missions. It is very difficult to implement high quality only depending upon the stucture design or aerodynamic configuration. It is the important development to adopt the flight control system (PCS) to improve handling quality, and control law design plays an important role in helicopter handling quality design.
    Currently, one of the hotspots in the research of helicopter flight control technology is to define performances of PCS based on handling quality standard, and to implement criteria requirements directly in PCS. Conventional technology of PCS design cannot meet the requirements for quality design.
    In order to provide a basic and effective practical engineering tool for handling quality planning, analysing and evaluating, which is needed hi helicopter prototype development, this research work is launched on the fundation of comprehending the new
    aeronautical standard of United States Army-ADS-33, and has obtained the
    achievements as following:
    (1) Performance definition of PCS according to the criteria requirements for an explicit helicopter, beginning at analysis of its missions.
    (2) Establishment of a helicopter attitude controller, which can meet the criteria requirements, by using the technology of adaptive neural network model-inverse control; Implementation of two response types (RTs) and two control modes; Evaluation of quantitative parameters according to the ADS-33.
    (3) Establishment of a helicopter trajectory contoller based on the attitude controller; Simulations of mission task elements (MTEs) and evaluation of handling quality.
    The following conclusions have been drawn from this research program,:
    (1) The model following architecture allows for straightforward implementation of requirements of handling quality standard, and it can be utilized for helicopter handling quality design.
    (2) The adaptive model-inverse control theory can provide the referenced helicopter with consistent handling quality throughout its operating envelope, with requiring only an approximate linear model at a single operating point.
    
    
    (3) The technology of adaptive neural network model-inverse control can reduce costs and period associated with PCS development.
    (4) The adaptive neural network has a potential ability of PCS redesign and maintenance of handling quality, following unexpected part failures and battle damage.
    (5) The trajectory controller can be utilized for MTEs simulation and handlling quality evaluation.
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