舵机是飞行器控制系统中的执行装置。它的核心部分就是一套电液伺服系统，它的原理是根据放大器传来的控制信号, 以规定的输出速度和输出力推动飞机的舵面。从而达到控制飞行器目标姿态的一套复杂装置。现代飞行器对飞行性能的要求越来越高，从而使得操纵特性及气动力特性都变的更为复杂，同时也对舵机的研制提出了更高的要求。 舵回路是自动驾驶仪回路的一部分，它主要包括控制器，液压舵机和反馈装置三个部分。其中液压舵机包括电液伺服阀，作动器。现代飞行器由于对安全性和可靠性的要求，一般都具有两种工作模态，电传模态和机械模态，它们分别通过电信号和机械信号控制阀体，从而驱动作动器带动舵面偏转，反馈装置的作用是反馈作动器的位移完成闭环控制。机械操控模态是液压舵机使飞机能够正常工作的另一个重要手段。也是飞行器安全操控的最后一道屏障。 在机械模态中，平板阀和作动器是舵机的关键部件，对机械模态下液压舵机中的板阀、管路和作动器分别建立了数学模型，通过Matlab的仿真分析，得到了平板阀的死区及负载对作动器之间的纷争力和作动器输出位移的关系，然后又提出了改进方法，即增加作动器活塞旁通孔来解决纷争力现象，通过仿真分析基本验证了该方法是可行的。 在电传模态中，电液伺服阀和作动器是舵回路中最重要的液压原件，它关系到整个舵回路的性能，因此这两个液压原件的实际性能指标决定着整个舵回路的性能指标。首先分析电液伺服阀和作动器的结构和理化特性，然后依据分析结果建立其对应的数学模型，具体分析并研究了重要结构参数、不同负载对舵机的系统函数的作用，这些工作对舵机物理结构设计以及系统总体性能仿真都有很强的实际指导作用。在Matlab的模型仿真中，对该模式下舵机的动静态特性进行了仿真分析，并着重研究了电液伺服阀死区及负载对作动器之间的纷争力和作动器输出位移的关系及影响。通过仿真对舵机的设计起到了重要的指导作用。 电传液压舵机是一套电液伺服系统，其要能正常工作必须有控制器来完成闭环控制，电液伺服控制技术正是基于这种需求而产生的，它是液压传动与控制理论的综合，同时它也是新兴的跨学科的一门现代高新技术。电液伺服阀的出现，精确的完成了电到液的转换，使小功率的电信号控制大负载成为现实。本文舵回路控制器是基于模糊自适应PID控制理论，该控制器具有很好的鲁棒性和抗干扰能力，具有很好的控制效果。

The steering gear is the executing agency for the flight control system . Its core is a set of electro-hydraulic servo system , Its function is to promote the rudder of the aircraft in accordance with the control signal coming from the amplifier , to a certain degree of output speed and output force . So as to achieve the impact of a complex device for the purpose of aircraft flight attitude . Modern aircraft are increasingly demanding high performance , the handling characteristics and aerodynamic characteristics have become more complex , but also put forward higher requirements for the development of the steering gear . Rudder loop is part of the autopilot , which mainly includes three parts of the controller , hydraulic steering gear and the feedback device . Hydraulic steering gear , including electro-hydraulic servo valve actuator . Modern aircraft due to safety and reliability requirements , generally has two operating mode , fly-by-wire mode and mechanical manipulation mode . Respectively by electrical and mechanical instruction control valve to drive the actuator to drive the rudder deflection , Feedback device feedback rudder displacement complete closed-loop control . The mechanical manipulation modal is another important means of hydraulic steering gear of the aircraft to work properly , and also to control the aircraft 's last bulwark . The mechanical manipulation modal , the flat valve and actuator is a key component of the steering gear . The modal mechanical manipulation under hydraulic steering gear plate valves , piping and actuator establish a mathematical model . Matlab model simulation analysis of the plate valve dead load force disputes between the actuator and the output displacement , and proposed the set actuator internal bypass hole to solve the force disputes to the phenomenon , by the simulation results demonstrate the feasibility of this approach . Fly-by-wire mode , the electro-hydraulic servo valve and actuator are key components in the rudder circuit performance determines the quality of the entire rudder loop can achieve performance index requirements . Therefore, the corresponding mathematical model of the electro-hydraulic servo valve and actuator , analyze and study the impact of key structural parameters , the transfer function of the type of load on valve control actuator simulation of the design and the overall performance of the steering gear structure has important theoretical significance . In Matlab model simulation , the simulation analysis of the static and dynamic characteristics of the steering gear mode , focusing on the analysis of the electro-hydraulic servo valve dead load force disputes between the actuator and the output displacement . Simulation has played an important role in guiding the design of the steering gear . Fax hydraulic steering gear is a set of electro-hydraulic servo system , to be able to work properly must have the controller to complete the closed-loop control . A modern technology of electro-hydraulic servo control technology is a comprehensive hydraulic drive and control theory , and it is also emerging interdisciplinary . The conversion of electrical and fluid use of electro-hydraulic servo valve , the small power electrical signals to control a large load to become a reality . This article rudder loop controller based on fuzzy adaptive PID control theory , the controller has good robustness and anti-interference ability and has good control effect .