PSS 3-2-1正交并联机构动平台的位姿控制

提出了一种便于实现的,简单方便的控制策略,即基于新型正交六自由度并联机构动平台系统的运动学特性,首先对动平台的逆运动学进行分析,建立逆运动学方程,然后建立无刷电动机的数学模型,由给定的平台质心的预期轨迹,通过逆解解出各运动支链的位移矢量,将其作为由驱动电机和编码器构成的半位移闭环的系统输入量,设计了一个模糊PID自整定控制器,用控制器对支链杆长变化进行跟踪,最后进行仿真实验。结果表明了所设计的模糊PID自整定控制器比模糊PID控制器能明显地改善控制系统的动态性能,具有响应速度快,调节时间短,稳定性好,抗干扰能力强,可以快速跟踪给定杆长变化,提高了系统的动态性能,证明了该控制方法的有效性,为PSS 3-2-1正交并联机构动平台的控制奠定了基础。     

水池拖车转矩主从模糊自整定控制系统

采用主从控制模式有效地解决了水池拖车控制系统4台直流驱动电机的速度同步和负载平衡问题.传统的直流电动机双闭环调速系统多采用结构简单、性能稳定的带限幅的PI调节控制器,传统的PI调节器很难满足快速、超调小和抗干扰能力强等要求,特别是在模型参数时变、控制对象非线性和众多干扰因素的情况下.采用模糊自整定PI控制器,利用模糊推理方法实现对PI参数的在线自整定.通过实验仿真证明,该系统在不同的运行环境下都能有良好的静态和动态性能.     

多机驱动带式输送机功率平衡模糊控制方法

针对以调速型液力偶合器作为驱动装置的带式输送机多机驱动系统采用传统方法控制各驱动电动机之间的功率平衡,存在系统运行过程中动态特性较差、功率平衡调节精度较低等问题,提出一种多机驱动带式输送机功率平衡模糊控制方法:对液力偶合器涡轮转速实行闭环控制,保证在工作机负载发生变化时带式输送机具有恒定不变的带速;转速调节器采用模糊控制器代替传统的PID控制器,以提高功率平衡的调节精度。Matlab仿真结果表明,采用模糊控制方法可有效改善系统动态性能,提高功率平衡调节精度。     

Intelligent control of a stepping motor drive using an adaptive neuro–fuzzy inference system

Stepping motors are widely used in robotics and in the numerical control of machine tools where they have to perform high-precision positioning operations. However, the variations of the mechanical configuration of the drive, which are common to these two applications, can lead to a loss of synchronism for high stepping rates. Moreover, the classical open-loop speed control is weak and a closed-loop control becomes necessary. In this paper, fuzzy logic is applied to control the speed of a stepping motor drive with feedback. A neuro-fuzzy hybrid approach is used to design the fuzzy rule base of the intelligent system for control. In particular, we used the ANFIS methodology to build a Sugeno fuzzy model for controlling the stepping motor drive. An advanced test bed is used in order to evaluate the tracking properties and the robustness capacities of the fuzzy logic controller.     

基于C8051F020的假肢控制系统设计

以C8051F020单片机为核心处理器,设计了仿人手臂形假肢的控制系统。系统采用单片机自身集成的PCA模块产生占空比可调的PWM信号用于驱动三个直流电机,采用定时器产生频率信号用于驱动三个步进电机,采用CPLD对各个关节控制量的检测并实时地反馈给控制器实现实时控制。在此基础上设计出了按键控制和语音控制两种控制方式。该系统不但结构简单、操作方便,而且可靠性高。     

用于汽车耐久性试验的驾驶机器人模糊控制仿真

介绍一种用于汽车耐久性试验驾驶机器人模糊控制方法。驾驶机器人由交流伺服电机、控制器、滚珠丝杠以及机械定位装置组成。阐述了模糊控制的原理、模糊PID控制器的设计规则和设计过程。在MATLAB环境仿真模拟机器人位置伺服系统,表明了模糊PID控制器的有效性。     

Feedback linearizing and sliding mode control of a variable reluctance motor

Direct-drive connection of electric motors represents a suitable solution to friction and backlash problems introduced by mechanical reduction gears. Variable reluctance (VR) are a special type of switched reluctance motors whose construction is well suited for direct-drive connection. Although these motors are traditionally conceived as stepper motors, continuous motion can be obtained by implementing suitable closed-loop control in the drive. The authors' main aim is to design a high-performance robust controller for a VR motor intended for velocity trajectory tracking in robotics applications where continuous motion is required. A cascade controller structure (velocity-torque) is considered. In the design of the torque controller, both feedback linearizing and sliding mode techniques are considered. Feedback linearization performs slightly better in the ideal case, but under more realistic operating conditions the sliding mode controller demonstrates comparable or even better performance. A very simple but extremely robust velocity controller is designed using a dynamic sliding mode approach, ensuring robustness to large variations of load torque and inertia, typical of direct-drive robotics applications. A simulation experiment of the overall controller with the motor connected to a single link robotic arm shows very good tracking properties as well as insensitivity to large variations of load torque and inertia.     

Design of a PID-like compound fuzzy logic controller

The paper describes a novel method for the design of a fuzzy logic controller (FLC) with near-optimal performance for a variety of operating conditions. The approach is based on the analysis of the system behaviour in the error state-space. The final control structure, in a form of a compound FLC, is arrived at in two stages. The first stage encompasses design and tuning of a PID-like fuzzy controller. The second stage consists of placing an additional fuzzy controller, of a structure similar to that of the first one, in parallel with the PID-like fuzzy controller designed in the first stage. The resulting compound controller is characterised with high performance in the wide range of operating conditions, and with small number of parameters that can be adjusted using simple optimisation methods. The controller is developed and tested for a plant comprising a vector controlled induction motor drive.     

Adaptive control of harmonic drive with parameter varying friction using structurally dynamic wavelet network

In this paper, an adaptive controller with structurally dynamic wavelet network is developed for a harmonic drive subject to parameter varying friction. The control architecture integrates a proportional controller, a feedback adaptive component and sliding component to adaptively compensate for the friction to achieve accurate position tracking. Global asymptotic stability of the algorithm is proved by using Lyapunov function. In parallel to the adaptive controller, a fuzzy reconfiguration scheme is devised to change the structure of the network along with weights updating to improve the system tracking performance and robustness. Experimental tests on a harmonic drive manipulator verify the effectiveness of the proposed control method.     

基于中立型系统理论的异步电机电流解耦控制方法

针对异步电机传统系统建模中忽略数字延时,造成建模不精确,加剧电流环中两电流间的交叉耦合,导致低开关频率的传动系统电流畸变、系统不稳定等严重问题,运用中立型理论,提出一种基于中立型的异步电机电流解耦控制方法,设计中立型电流控制器.该电流控制方法具有参数自动整定的优点,且耦合小、响应快、鲁棒性好,该理论通过建立精确的数学模型来解决数字延时问题对传动系统控制性能的影响.对异步电机中立型时滞系统进行稳定性分析,通过仿真和实验结果表明了所设计中立型电流控制器的可行性.     

A multirule-base controller using the robust property of a fuzzycontroller and its design method

This paper suggests a new fuzzy adaptive controller, which is able to solve the problems of classical adaptive controllers and conventional fuzzy adaptive controllers. It explains the architecture of a fuzzy adaptive controller using the robust property of a fuzzy controller. The basic idea of new adaptive control scheme is that an adaptive controller can be constructed with parallel combination of robust controllers. This new adaptive controller uses a multirule-base architecture which has several independent fuzzy controllers in parallel, each with different robust stability area. Out of several independent fuzzy controllers, the most suited one is selected by a system identifier which observes variations in the controlled system parameter. Here, we propose a design procedure which can be carried out mathematically and systematically from the model of a controlled system; related mathematical theorems and their proofs are also given. The performance of the proposed adaptive control algorithm is analyzed through a design example and a DC motor control simulation     

Cascade fuzzy variable structure control of induction motor based on the approach of fuzzy modelling of Ben-Ghalia

In this article, a control design concept using fuzzy sets for an induction motor is presented. The aim of the proposed modelling approach is to provide a fuzzy set-based representation of the cascade sliding mode control of an induction motor fed by PWM voltage source inverter, which operates in a fixed reference frame. For this purpose, a new decoupled and reduced model is first proposed. Then, a set of simple surfaces and associated control laws are synthesised. A piecewise smooth control function with a threshold is adopted. However, the magnitude of this function depends closely on the upper bound of uncertainties, which include parameter variations and external disturbances. This bound is difficult to obtain prior to motor operation. To solve this problem, a fuzzy modelling approach is presented to improve the design and tuning of a fuzzy logic controller using variable structure control theory. The robust fuzzy control design is made feasible without resorting to model simplification or imposing restrictive conditions on the system uncertainty. The fuzzy controller is designed in order to improve the control performances and to reduce the control energy and the chattering phenomenon. Simulation results reveal some very interesting features and show that the proposed fuzzy sliding mode controller could be considered as an alternative to the conventional sliding mode control of induction motors.     

Speed control of induction motors using a novel fuzzy sliding-modestructure

This paper presents a new approach to indirect vector control of induction motors. Two nonlinear controllers, one of sliding mode type and the other PI-fuzzy logic-based, define a new control structure. Both controllers are combined by means of an expert system based on Takagi-Sugeno fuzzy reasoning. The sliding-mode controller acts mainly in a transient state while the PI-like fuzzy controller acts in the steady state. The new structure embodies the advantages that both nonlinear controllers offer: sliding-mode controllers increasing system stability limits, and PI-like fuzzy logic based controllers reducing the chattering in permanent state. The scheme has been implemented and experimentally validated     

基于Simulink仿真的步进电机闭环控制系统分析

步进电机通常以开环方式应用于精度要求不高的位置伺服系统中.通过位置反馈,可以实现步进电机的高精度闭环定位控制.建立的步进电机数学模型,显示了其高度非线性的特点,为此设计了应用于步进电机闭环控制的参数模糊自整定PID控制器.通过Simulink仿真,分别分析了PID控制、模糊PID控制在步进电机跟踪给定位置时系统的响应情况.并通过分析转速输出曲线,提出了加入模糊速度前馈控制环的系统改进方案,系统稳定性得到较大提高.     

一类不确定多输入模糊双线性系统的鲁棒H∞控制

针对一类带有参数不确定性和干扰的多输入模糊双线性系统(FBS)的鲁棒H_∞控制问题,使用并行分布补偿算法(PDC)设计了模糊控制器,得到了整个模糊控制系统鲁棒全局稳定的充分条件,控制器的设计可以通过求解一系列线性矩阵不等式(LMI)获得.仿真例子验证了方法的有效性.     

步进电动机的模糊PID控制

由于步进电动机调速系统具有非线性等特点,使得利用简单模糊控制与传统PID控制精度不高,因此文中提出利用模糊PID控制器实现对步进电动机调速系统进行控制的方法,并设计了模糊PID控制器。文中首先建立了步进电动机的数学模型,并根据数学模型推导了其传递函数;然后介绍了模糊PID控制器结构,以及模糊控制规则的生成方法,并且对该控制方案进行数字仿真。仿真结果表明:该方法调节精度较高,动态响应快,无超调,有一定的可行性。     

Hierarchical fuzzy controllers for an astronomical telescope tracking

The paper presents an application of fuzzy logic controller (FLC) with hierarchically structured rule base for a two-link direct drive Celestron telescope. The hierarchical fuzzy logic controller (HFLC) is implemented, as nonlinear blocks used in a control system, for supervision of PID controller for position tracking of the telescope driven by electric motors. The HFLC is composed of two FLC stages connected in cascade. The input variables, for the first stage, of the HFLC are the position error and the rate of change in the position error. Then the output from the first stage and the position error integral are used as input variables for the second stage of the HFLC PID. The simulation results of the proposed HFLC PID, when the telescope is subjected to a unit step in reference position, are compared with the PID controller. The dynamic responses of the HFLC PID improve the rise time, damping factor and settling time compared with the PID controller. Also, the proposed techniques, hierarchical fuzzy PID controller, reduce the computation time due to reduction of rule base. The simulation results show the effectiveness of the proposed HFLC PID controller scheme as a promising technique.     

大功率双电机拖动系统模糊控制算法的研究

本文针对双电机拖动系统的特殊性,构造了参数自调整模糊控制双闭环直流调速系统.通过实测波形可以看出,模糊控制器不仅保持了常规PID控制系统的优点,而且具有更大的灵活性、适应性、控制精度更高,是日前较为先进的一种控制系统.     

RCMAC-based adaptive control design for brushless DC motors

This paper proposes a recurrent cerebellar model articulation controller (RCMAC)-based adaptive control for brushless DC motors. This control system is composed of a RCMAC and a compensation controller. RCMAC is used to mimic an ideal controller, and the compensation controller is designed to compensate for the approximation error between the ideal controller and RCMAC. The Lyapunov stability theory is utilized to derive the parameter tuning algorithm, so that the uniformly ultimately bound stability of the closed-loop system can be achieved. For comparison, a fuzzy control, an adaptive fuzzy control and the developed RCMAC-based adaptive control are implemented on a field programmable gate array chip for controlling a brushless DC motor. Experimental results reveal that the proposed RCMAC-based adaptive control system can achieve the best tracking performance. Moreover, since the developed RCMAC-based adaptive control scheme uses a hyperbolic tangent function to compensate for the approximation error, there is no chattering phenomenon in the control effort. Thus, the proposed control method is more suitable for real-time practical control applications.     

直流调速系统中常规PI 与模糊PI 控制器的比较

转速电流双闭环直流调速系统中的PI控制器直接影响其调速性能,利用MATLAB分别建立了由常规PI与模糊PI控制器组成的转速电流双闭环控制直流调速系统的仿真模型,并进行了仿真。仿真结果表明,模糊PI控制器与常规PI控制器相比具有更好的动态稳定性和跟踪性能,对外界干扰具有较强的鲁棒性。