Fuzzy robust nonlinear control approach for electro-hydraulic flight motion simulator

A fuzzy robust nonlinear controller for hydraulic rotary actuators in flight motion simulators is proposed. Compared with other three-order models of hydraulic rotary actuators, the proposed controller based on first-order nonlinear model is more easily applied in practice, whose control law is relatively simple. It not only does not need high-order derivative of desired command,but also does not require the feedback signals of velocity, acceleration and jerk of hydraulic rotary actuators. Another advantage is that it does not rely on any information of friction, inertia force and external disturbing force/torque, which are always difficult to resolve in flight motion simulators. Due to the special composite vane seals of rectangular cross-section and goalpost shape used in hydraulic rotary actuators, the leakage model is more complicated than that of traditional linear hydraulic cylinders. Adaptive multi-input single-output(MISO) fuzzy compensators are introduced to estimate nonlinear uncertain functions about leakage and bulk modulus. Meanwhile, the decomposition of the uncertainties is used to reduce the total number of fuzzy rules. Different from other adaptive fuzzy compensators, a discontinuous projection mapping is employed to guarantee the estimation process to be bounded. Furthermore, with a sufficient number of fuzzy rules, the controller theoretically can guarantee asymptotic tracking performance in the presence of the above uncertainties, which is very important for high-accuracy tracking control of flight motion simulators.Comparative experimental results demonstrate the effectiveness of the proposed algorithm, which can guarantee transient performance and better final accurate tracking in the presence of uncertain nonlinearities and parametric uncertainties.     

基于可编程逻辑控制器的超声电机测试系统设计

为了给工程技术人员提供易于操控的超声电机特性测试设备,设计了基于可编程逻辑控制器(PLC)的测试系统。根据超声电机常用的特性要求,利用力矩传感器输出的脉冲信号,通过PLC的高速输入口,用梯形图实现力矩和转速的采集和显示。通过可编程逻辑控制器配套的人机界面,实现了触摸屏对超声电机的测试进行操作。测试系统能够完成超声电机机械特性测试、超声电机自动加减载测试、超声电机带负载起动特性测试和超声电机手动测试等4种模式。通过试验对该系统进行验证,达到易于操作的要求。     

电力机车PMSM自适应模糊滑模控制

为研究牵引工况下电力机车永磁同步电机(PMSM)的转速控制精度,考虑轮轨接触不平顺及车体静载荷在轮对径向产生的未知时变负载转矩,建立了机车PMSM在dq坐标系下的数学模型。针对该耦合非线性系统中存在的负载转矩,设计非线性转矩观测器对其实际值进行估计,对观测误差采用自适应模糊逻辑系统进行逼近;为考察d轴电压过零跳变对转速控制及转矩观测性能的影响,在d轴电压控制器设计中引入Nussbaum函数,并依据Lyapunov稳定性理论,构造了基于转矩观测器的自适应模糊滑模控制器。理论分析及仿真结果表明,当转矩时变或d轴电压过零时,机车PMSM闭环转速控制系统跟踪误差一致有界,转矩观测误差收敛于0。     

航空发动机部件性能故障融合诊断方法研究

提出一种对航空发动机部件性能蜕化进行融合诊断的模糊决策融合机制,以改善单独采用基于模型和基于数据的部件性能故障诊断的漏诊与误诊的问题.传感器测量值同时输入到基于自适应模型的和基于数据的诊断模块中,分别利用卡尔曼滤波算法和最小二乘支持向量机(LSSVM)对主要部件故障性能参数估计,再利用模糊逻辑调整决策权重以进行D-S(Dempster-Shafer)证据理论的决策融合诊断.以某型涡扇发动机为对象进行单部件和双部件蜕化仿真研究表明,与单独使用基于模型和基于数据的诊断方法相比,采用决策融合机制有效地提高了部件故障诊断精度.      

ROBUST ADAPTIVE BANK-TO-TURN MISSILE AUTOPILOT DESIGN USING FUZZY CMAC NEURAL NETWORKS

ＲＯＢＵＳＴＡＤＡＰＴＩＶＥＢＡＮＫ┐ＴＯ┐ＴＵＲＮＭＩＳＳＩＬＥＡＵＴＯＰＩＬＯＴＤＥＳＩＧＮＵＳＩＮＧＦＵＺＺＹＣＭＡＣＮＥＵＲＡＬＮＥＴＷＯＲＫＳＺｈａｎｇＹｏｕａｎ（张友安）,ＣｕｉＰｉｎｇｙｕａｎ（崔平远）,ＷａｎｇＳｈｏｕｂｉｎｇ（王守斌...     

空间智能桁架模糊振动控制研究

研究了模糊控制应用于多输入、多输出的空间智能桁架系统的振动控制.首先建立空间智能桁架的有限元方程,在此基础上,设计了一个标准的模糊控制器,并通过选择合适的量化因子将该标准模糊控制器应用于每一对同位布置的作动器/传感器,各个控制器之间独立工作.这样就避免了设计MIMO模糊控制器带来的复杂问题.最后针对空间智能桁架进行仿真,结果表明,设计的模糊控制器可以有效抑制桁架的振动,并且具有结构简单、鲁棒性强、抑制控制溢出的优点.     

计算机简化逻辑代数式

本文的目的是用计算机对数字电路、模糊数学领域及其他技术领域中广泛使用的逻辑代数式进行简化,以前简化逻辑代数式的方法一般采用公式法、真值图法、观察法及其他方法处理,但是随着科学技术的飞跃发展,逻辑中所含的变量数目越来越多,给人们的简化工作带来了困难。本文为此对逻辑代数式的规律进行分析,提出用计算机计算的公式,并提出减小计算工作量的方法。     

遗传算法与模糊逻辑的双向集成

简要介绍了模糊逻辑和遗传算法相互结合的途径与方法 ,并提出了一些其中有可能出现的问题。文章认为二者在很多方面具有互补性 ,可以进行广泛而深度地结合 :一方面可以用模糊控制规则来提高遗传算法的性能 ,克服未成熟收敛等现象 :另一方面 ,应用遗传算法可以有助于模糊逻辑的数据库、规则库和知识库的设计与构造。     

无线电高度表修理级别确定方法研究

介绍了装备修理级别分析方法。在装备维修缺乏数据的情况下,应用修理级别逻辑决断法对装备维修保障的有效性和可行性进行了研究,并举例进行了说明。     

FERA in parameter identification with application in low speed wind tunnel test

This paper presents a new approach which consists of a fuzzified eigensystem realization algorithm (FERA) to identify the parameters of the designed mini-UAV model performance in the low speed wind tunnel (LSWT) power on testing system. On the basis of the identification scheme, it is able to reduce system operational cost of wind tunnel tests and provide a tool for predicting results without resorting to on-site experiments. A variety of variables in model types and testing environment such as model profile, angle of attack, elevator, tunnel wind speed and power system (motor and propeller) are considered. The method based on logic devices is simple yet effective. The results obtained are compared to those obtained by the conventional wind-tunnel testing method. To verify effectiveness of the proposed methodology, both of simulations and real-world experiments are conducted. The results show that the working performance of the proposed method correlates well with expectation.