一类脉冲量为非线性函数的不确定系统的脉冲控制

由于脉冲控制系统响应速度快,有鲁棒性和抗干扰能力强等特点,被广泛研究。在实际系统中,总存在各种干扰。针对一类带有非线性扰动的不确定性系统,脉冲量为非线性函数的脉冲控制系统的稳定性,应用脉冲控制基本理论进行研究,得出了鲁棒稳定性判据,最后通过一个实例说明了所得结果。     

基于自抗扰控制半潜平台动力定位控制器设计

本文采用自抗扰控制技术,设计了半潜式平台动力定位控制器.跟踪微分器实现给了平台定位置的快速稳定跟踪;非线性扩张观测器能进行平台运动位置、速度和系统扰动的估计,通过非线性反馈控制对系统总扰动进行补偿,实现了平台定位的精确控制.经仿真实验验证：该控制器具有响应快、精度高、稳定性好,抗干扰能力强、鲁棒性强等优点.     

采用自抗扰控制的空间激光通信精跟踪系统

空间激光通信的视轴稳定是激光通信链路建立的前提。针对通信终端载体的非线性扰动和扰动模型未知造成视轴稳态误差较大的问题,设计了自抗扰控制方法,并采用模糊控制理论自适应调整非线性状态误差反馈控制律中的相关参数。实验结果表明,与自适应PID控制方法相比,采用模糊自抗扰控制方法可以有效抑制平台的非线性扰动,并且具有较快的响应速度与较强的鲁棒性,可以满足系统的稳态精度要求。     

基于自抗扰控制的光电平台视轴稳定技术研究

针对影响光电平台控制精度的载体速度扰动以及测量噪声等因素,设计了扰动自抗扰以及滤波控制的两部分控制策略。首先,通过分析光电平台伺服系统速度稳定环的数学模型中扰动作用原理,等效各个扰动作用并提出扰动总和思想,设计了基于降阶扩张状态观测器的自抗扰控制器。其次,利用卡尔曼滤波器对系统中测量噪声进行了滤波处理,降低了扩张状态观测器的估计误差。最后,详细地进行了传统PI控制系统与文中设计的卡尔曼自抗扰控制系统的对比实验。实验结果表明,在设计带宽相同的情况下,卡尔曼自抗扰控制系统相比PI控制系统的阶跃响应稳定时间减小32.53%,超调幅值减小72.73%;当使用摇摆台引入幅值为1频率、在2.5 Hz以内的正弦扰动时,卡尔曼自抗扰控制系统较PI控制系统的扰动隔离度提升了54.67%以上;在系统模型参数改变15%范围内,卡尔曼自抗扰控制系统仍具有优异的扰动隔离性能,表现出较强鲁棒性,满足光电平台视轴稳定的性能要求,对提升视轴稳定精度有较高实用价值。     

大时滞温度控制系统的改进型算法

本文以具有时滞不确定特征的大时滞温度控制系统为研究对象,提出一种改进型Smith预估控制算法,并研究该控制算法的稳定性及鲁棒性等问题.通过其稳定性和鲁棒性的理论分析及模型仿真,证明了其稳定性能好和抗扰动能力强的特点.     

机载激光通信的重复自抗扰视轴稳定控制

机载激光通信的视轴稳定是建立激光通信链路的前提。针对通信终端载体的非线性扰动和扰动模型未知造成视轴稳态误差较大的问题,结合自抗扰控制与重复控制,提出了重复控制补偿自抗扰算法,以完全消除周期性稳态跟踪误差。仿真实验结果表明,与自适应PID控制方法相比,重复控制补偿自抗扰算法可以有效抑制平台的非线性扰动,提高了系统的稳态精度,并且具有较快的响应速度与较强的鲁棒性。     

基于压电陶瓷神经网络模型的模型抑振研究

为达到在脉动气流激励下抑制风洞模型振动的目的,该文提出了基于压电陶瓷作动器神经网络模型的风洞模型主动振动控制方法,并进行了实验研究。首先,分析了风洞模型系统振动特性,建立了内嵌式压电陶瓷作动器的主动振动控制系统,通过模型质心加速度推算出压电陶瓷作动器期望输出抑振力。然后,建立了压电陶瓷作动器期望输出抑振力 激励电压的神经网络模型,并根据该模型设计了一种实时解算加速度为激励电压的控制方法。最后,通过地面试验对控制方法的有效性进行验证。实验结果表明,该控制方法具有良好的实时性和鲁棒性,在锤击试验中,振动加速度衰减时间相比于压电方程线性控制时减小了54.46%,系统阻尼比增大了1.58倍,取得了良好的控制效果。     

改进的单相全桥逆变器双环控制研究

双环控制外环为电压环,而内环则分为电感电流内环和电容电流内环。在此对这俩种方法的不同之处进行了理论分析,为了改善该种控制系统在抗负载扰动方面的不足,在双环控制的基础上引入了负载电流前馈的设置。通过负载电流前馈控制的设置,有效地提高了该种控制抗负载的扰动性能,从而增强了系统的稳定性和改善了逆变器电压输出波形质量。     

基于滤波器的机器人滑模控制

变结构控制系统是一类特殊的非线性控制系统,滑模控制就是其中的一种控制策略。滑模控制对系统参数及扰动的变化反应迟钝,具有很强的鲁棒性,该控制方法特别适合机器人系统的控制。抖振是滑模变结构控制中不容回避的问题。文中采用了后滤波器用于消除对象输出的噪声干扰,从仿真结果看,有效削弱了单纯滑模变结构控制系统的抖振。     

采用自调整模糊变结构控制的机载激光通信视轴稳定研究

机载激光通信的动态视轴稳定是建立激光通信链路的首要前提,传统的粗跟踪控制方法不能克服载体扰动及参数变化对系统的不利影响,影响了视轴稳定精度。根据控制系统的任务,将论域自调整模糊控制与滑模变结构控制的思想相融合,在稳定的误差相平面内构造稳定的滑模面。理论分析和模拟实验结果表明,该方法消除了系统的抖振现象,改善了系统的瞬态性能,对机载通信平台受到的扰动及参数变化具有完全的自适应性。因此自调整模糊变结构控制具有一定鲁棒性,且控制算法简单,可望获得工程应用。     

压电陶瓷定位系统电容传感器容错控制

针对压电陶瓷定位系统中电容传感器故障对定位精度的影响,对使用扩展卡尔曼滤波(EKF)进行容错控制的方法进行了研究。以传感器采样电路故障和掉电故障为对象,对三阶轨迹规划算法下电容传感器的EKF滤波公式进行了分析,提出以离散化迭代计算的EKF代替传统的将非线性系统线性化的方法。在压电陶瓷定位系统实验平台上,使用激光干涉仪作为测量基准,在传感器采样电路故障和掉电故障的情况下,实现了500μm行程,绝对精度小于3.5μm,误差小于0.7%的定位控制。结果表明,基于EKF的电容传感器容错控制可以有效减小传感器故障引起的控制误差,增加压电陶瓷定位系统的鲁棒性。     

Control of hybrid nanopositioning systems for trajectory-tracking applications

In many industrial applications positioning systems are required to follow trajectory paths in the range of several centimeters and featuring at the same time a nanometre-range precision. Neither pure piezoelectric stages nor standard positioning systems with motor and spindle are able to meet such requirements as a single actuator, because of the small operation range on the one hand and inadequacies like backlash and friction on the other hand. Hybrid positioning systems, realized as a combination of a “coarse” and a “fine” actuator, aim to solve this problem. The wide range of applications enables a considerable market potential for such devices, but yields changing control requirements due to the high variety of possible positioned objects and positioning tasks and requires therefore a high-performance control system.In this paper a model-based control design for piezoelectric hybrid nanopositioning systems is presented. The proposed control consists of a multivariable state-feedback control on the basis of a novel plant representation offering a sufficient robustness. The designed control is realized and experimentally tested with a commercially available hybrid nanopositioning system featuring a DC drive, representing the coarse actuator, and a piezoelectric actuator utilized as fine actuator.     

压电微执行器在硬盘伺服系统的应用研究

介绍一个硬盘双伺服控制系统的设计和实现。双伺服系统是在硬盘固有的音圈电机上附加了一个压电微执行器,用来执行更快捷、精确的磁头定位。对音圈电机的控制设计采用了一种线性反馈控制技术,结合扰动估计和补偿实现快速、平稳和无静差的设定点跟踪。基于开环逆控制的思想,微执行器环路的控制采用定值比例及滤波器,使得合并的位移输出能更快地跟踪设定点(磁道)。仿真和实验结果证明双伺服控制系统可以实现更快速、精确的磁头定位。     

Design and control of a rotary dual-stage actuator positioning system

This paper presents the design and control of a rotary dual-stage actuator (DSA) positioning system, which has a flexure-based beam driven by a voice coil motor (VCM) and a piezoelectric (PZT) actuator simultaneously. The design goal is to enable the two actuators complementary to each other for the combined ability of high positioning accuracy and a large tangential displacement range. To achieve a high tracking speed, the flexure beam is designed via finite element method (FEM) analysis to have sufficiently high open-loop bandwidth. System identification and measurements on the DSA prototype are also presented to verify the FEM analysis. Finally, the composite nonlinear control (CNC) method is applied to the DSA system. Experimental results demonstrate that the DSA servo system significantly outperforms the single-stage servo system in both step tracking and disturbance rejection.     

基于线性滤波器的四旋翼无人机强化学习控制策略

针对四旋翼无人机(UAVs)系统,该文提出一种基于线性降阶滤波器的深度强化学习(RL)策略,进而设计了一种新型的智能控制方法,有效地提高了旋翼无人机对外界干扰和未建模动态的鲁棒性。首先,基于线性降阶滤波技术,设计了维数更少的滤波器变量作为深度网络的输入,减小了策略的探索空间,提高了策略的探索效率。在此基础上,为了增强策略对稳态误差的感知,该文结合滤波器变量和积分项,设计集总误差作为策略的新输入,提高了旋翼无人机的定位精度。该文的新颖之处在于,首次提出一种基于线性滤波器的深度强化学习策略,有效地消除了未知干扰和未建模动态对四旋翼无人机控制系统的影响,提高了系统的定位精度。对比实验结果表明,该方法能显著地提升旋翼无人机的定位精度和对干扰的鲁棒性。     

Design and Performance Tuning of Sliding-Mode Controller for High-Speed and High-Accuracy Positioning Systems in Disturbance Observer Framework

The tuning method of controllers can be used for effectively determining the overall performance of positioning systems. In particular, this method is highly effective in the case of high-speed and high-accuracy positioning systems. In this paper, a sliding-mode controller that uses one of the well-known approaches of robust control methodology is designed for high-speed positioning systems that require a high-accuracy performance. A performance-tuning method based on a disturbance observer (DOB) structure is also proposed. First, a generalized disturbance attenuation framework named robust internal-loop compensator (RIC) is introduced, and a sliding-mode controller based on a Lyapunov redesign is analyzed in the RIC framework. Then, the DOB properties of the sliding-mode controller are presented, and it is shown that the performance of the closed-loop system with a sliding-mode controller can be tuned up by using the structural characteristics of the DOB. These results make the design of an enhanced sliding-mode controller possible. Finally, the proposed algorithm is experimentally verified and discussed with two positioning systems. Experimental results show the effectiveness and the robustness of the proposed scheme.     

Predictive control with enhanced robustness for precision positioning in frictional environment

A modified predictive control strategy is developed to overcome positioning and tracking difficulties for a transmission mechanism with friction. Enhanced robustness with respect to unknown dynamics is achieved by incorporating a zero phase error tracking controller (ZPETC) and a time-delay disturbance estimation scheme. Time delay control is used to cancel disturbances and potential nonlinearities. ZPETC is included to improve the overall system bandwidth. Both realistic numerical simulations, which consider the effect of sampling, quantization, and friction, and practical experiments are performed to investigate the effectiveness of the proposed control method. Encouraging transient response and steady-state control performance were observed in the results of positioning control of a one-dimensional transmission mechanism.     

Self-Sensing Actuation With Adaptive Control in Applications With Switching Trajectory

This paper presents the application of self-sensing actuation (SSA) to facilitate the implementation of piezoelectric actuator in an intelligent mechatronic system. SSA is a technique to employ smart materials, such as piezoelectric materials, simultaneously as a sensor and an actuator; thereby increasing the level of integration of the system. The piezoelectric actuator is equipped with an exclusive adaptive controller amidst its nonlinearities and system's disturbance. The application area to be discussed is a microdispensing system, which is an example of a micromanufacturing process, combining a fluidic system and a positioning system.     

Kalman filter and LQ based speed controller for torsional vibrationsuppression in a 2-mass motor drive system

In this paper, a high-performance speed control for torsional vibration suppression in a 2-mass motor drive system, like a rolling mill which has a long shaft and large loadside mass or a robot arm which has flexible coupling, was studied. The speed control method which has better control response than a typical one in command following, torsional vibration suppression, disturbance rejection, and robustness to parameter variation, was proposed. The performance of command following, torsional vibration suppression, and robustness to parameter variation was satisfied by using a Kalman filter and LQ based speed control with an integrator. Also, disturbance rejection performance was improved through load torque compensation. Through various experiments of a real 22 kW field oriented controlled AC motor drive system having 2-mass mechanical system, the characteristics of the proposed speed controller and typical PI speed controller were compared and analyzed     

微型计算机系统抗干扰技术

介绍了微型计算机系统中硬件抗干扰和软件抗干扰2类抗干扰技术的基本概念;针对不同的干扰因素,详细介绍了微型计算机硬件抗干扰技术的分类与应用,并从单片机应用角度讲述了软件抗干扰技术的应用。