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2020 12th International Conference on Electrical Engineering (ICEENG)最新文献

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Multi-variable Controllers for Cooperative Flight of Multi-Fixed Wing UAVs 多固定翼无人机协同飞行的多变量控制器
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171776
E. N. Mobarez, A. Sarhan, M. Ashry
This paper proposes a collaborative control system to be designed for multi-UAV. This makes it easy to perform many tasks at the same time and with high accuracy. Therefore, this cooperative control and guidance subsystems of the aircraft should have robust performance against sensors noise and wind disturbances. Four types of control algorithms were designed for a single Aerosonde UAV autopilot. This is to pick up which control algorithm is the best. As such, this control algorithm is proposed to be designed for the cooperative flight control system. Two classical control algorithms and two intelligent control algorithms have been proposed for the autopilot design of a single Aerosonde UAV. The first classical controller proposed is genetically tuned PID, while the second classical controller proposed is the fractional order PID. The first intelligent controller proposed for autopilot system is the Fuzzy logic controller known as FLC, while the second intelligent controller proposed is the adaptive neuro fuzzy inference system known as ANFIS. The proposed control algorithms have been applied to the nonlinear multivariable system of Aerosonde UAV. The analysis of simulation results assure that ANFIS is the best performance and the most robust control algorithm proposed. As such, ANFIS controller has been selected to be the cooperative flight controller system either in the low-level of a single UAV and in the top-level of multi-UAVs. Sometimes, classical controllers are preferred because of their simplicity in design. If this is the case, the simulation results assure that the genetically tuned fractional order PID controller- which proposed here for the first time with UAVs- is better than genetically tuned PID.
提出了一种针对多无人机的协同控制系统。这使得它很容易在同一时间执行许多任务,并具有很高的准确性。因此,飞机的协同控制和制导子系统应具有抗传感器噪声和风干扰的鲁棒性能。针对单个空探无人机自动驾驶仪设计了四种控制算法。这是为了找出哪个控制算法是最好的。因此,本文提出了一种针对协同飞行控制系统的控制算法。针对单架空探无人机的自动驾驶仪设计,提出了两种经典控制算法和两种智能控制算法。提出的第一个经典控制器是遗传调谐PID,而第二个经典控制器是分数阶PID。自动驾驶系统的第一种智能控制器是模糊逻辑控制器(FLC),第二种智能控制器是自适应神经模糊推理系统(ANFIS)。所提出的控制算法已应用于空探无人机的非线性多变量系统。仿真结果分析表明,ANFIS是一种性能最好、鲁棒性最强的控制算法。因此,无论是在单架无人机的底层,还是在多架无人机的顶层,都选择ANFIS控制器作为协同飞行控制器系统。有时,经典控制器因为设计简单而更受欢迎。在这种情况下,仿真结果保证了遗传调谐分数阶PID控制器(本文首次在无人机上提出)优于遗传调谐PID控制器。
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引用次数: 0
Calibration and Compensation of Scale Factor Non-linearity and Non-Orthogonality Errors for Dynamically Tuned Gyroscope (DTG) 动态调谐陀螺仪(DTG)尺度因子非线性和非正交误差的标定与补偿
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171734
Salem Abd El-Hakem Hegazy, AbdelMageed Mahmoud, A. Kamel, I. Arafa, Y. Elhalwagy
Inertial navigation system (INS) is utilized in several applications such as missile guidance, space navigation, and marine navigation. An efficient calibration method for improving the inertial navigation system accuracy is presented. As the vital error sources in the inertial navigation system are associated with the deterministic errors of the inertial measurement unit (IMU), the proposed technique precisely determines the calibration parameters to reduce these errors, especially the gyro’s scale factor, and non-orthogonality error. In recently proposed calibration methods, the scale factor is determined by the output/input relationship linear fitting. Although the determined scale factor meets the requirement of various navigation systems to some extent it doesn’t fit the high accurate ones, such as guided missiles and marines. That’s because the gyro damping effect is changed with different input angular rates which causes the gyro scale factor varying. The presented calibration method tackles this phenomenon by assigning different weights to each input rate through a weighted linear regression fit. Moreover, the gyro nonorthogonal error which comes from the imperfection gyro mounting is merely determined by the lateral coupling signal. But the fact is that the lateral coupling signal is not induced from the gyro non-orthogonal error only but also comprises the gyro signal which is directly proportional to the centripetal acceleration caused by the applied angular rates. Even though this signal is tiny but it will be accumulated for the long-time navigation system and degrades its accuracy. The presented calibration method utilizes a lateral accelerometer to realize that signal and tear out it to accurately obtain the nonorthogonal error. Finally, a laboratory test for the proposed method was carried out to ensure its effectiveness. Where the actual applied rates are determined twice, once with the built error model by the presented calibration method and the other by the traditional one.
惯性导航系统在导弹制导、空间导航和船舶导航等领域有着广泛的应用。提出了一种提高惯性导航系统精度的有效标定方法。由于惯性导航系统中的重要误差源与惯性测量单元的确定性误差有关,该技术通过精确确定标定参数来减小这些误差,特别是陀螺仪的标度因子和非正交性误差。在最近提出的校准方法中,尺度因子由输出/输入关系线性拟合确定。虽然确定的比例因子在一定程度上满足了各种导航系统的要求,但对于制导导弹和海军陆战队等高精度导航系统来说,比例因子并不适用。这是因为陀螺阻尼效应随输入角速率的不同而变化,从而引起陀螺尺度因子的变化。提出的校准方法通过加权线性回归拟合为每个输入率分配不同的权重来解决这一现象。此外,由陀螺安装缺陷引起的陀螺非正交误差仅由侧向耦合信号决定。但实际情况是,侧向耦合信号不仅是由陀螺非正交误差引起的,而且还包括与外加角速度引起的向心加速度成正比的陀螺信号。尽管这种信号很小,但它会在长时间的导航系统中积累并降低其精度。所提出的标定方法利用横向加速度计来实现该信号并对其进行提取,以准确地获得非正交误差。最后,对所提出的方法进行了实验室测试,以确保其有效性。其中实际应用速率确定了两次,一次是用本文方法建立的误差模型,另一次是用传统方法。
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引用次数: 0
A New Approach for Colonosocpy Advanced Movement using Finite Element Analysis 用有限元分析分析结肠镜高级运动的新方法
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171711
M. Rabie, M. Aref, M. Hamdan, T. Gourlay
Colon cancer is the second and third of the highest risk cancers for both men and women, respectively. There is no definite approach to inhibit the disease, but there are some methods that can be followed for decreasing it. This includes certain types of diets, medicines like aspirin or pain killers and educating people about its accompanying symptoms. There are several methods for colorectal cancer screening for detection and investigation of this disease such as Physical exam, patient’s history, digital rectal exam, barium enema, sigmoidoscopy, virtual colonoscopy, colonoscopy and capsule-like devices are several methods for colorectal cancer screening to detect and investigate this disease.ANSYS FEA software have been utilized for designing and modelling the electromagnetic actuators. Different actuators have been investigated for the colonoscope guidance through difficult regions of the colon, with the objective of optimizing safe penetration and reducing the risk of perforation.The present work produced a framework for novel electromagnetic actuators that can be used for colonoscope actuation and navigation purposes, which can produce a uniformly distributed magnetic field capable of generating high magnetic forces.
结肠癌分别是男性和女性的第二和第三高风险癌症。没有明确的方法来抑制这种疾病,但有一些方法可以减少它。这包括某些类型的饮食,阿司匹林或止痛药等药物,并教育人们了解其伴随症状。结直肠癌筛查的方法有多种,如体格检查、患者病史、直肠指检、钡灌肠、乙状结肠镜检查、虚拟结肠镜检查、结肠镜检查和胶囊装置等,是结直肠癌筛查发现和调查本病的几种方法。利用ANSYS有限元分析软件对电磁作动器进行了设计和建模。为了优化安全穿透和降低穿孔风险,研究了不同的执行器用于结肠镜引导通过结肠困难区域。目前的工作产生了一种新型电磁致动器的框架,可用于结肠镜的驱动和导航目的,它可以产生均匀分布的磁场,能够产生高磁力。
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引用次数: 0
Real Time Full States Integrated Low Cost Navigation System for Autonomous Vehicles 自动驾驶汽车实时全状态集成低成本导航系统
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171717
A. H. Hassaballa, A. Kamel, I. Arafa, Y. Elhalwagy
Accurate measurements of angular velocities and linear accelerations are required to achieve a precise navigation solution for autonomous vehicles (AVs). These measurements are readily available from the inertial measurement unit (IMU) which is considered the most crucial component in the AV autopilot system. Inertial navigation system (INS) comprises of IMU plus complicated process that converts the IMU measurements to navigation information (position, velocity, attitude, and time (PVAT)). To use low grade IMUs for constructing a reliable INS, a precise mechanization model with an intensive aiding filter has to be implemented to integrate other sensors such as Global Positioning System (GPS) and magnetometers to insure trustable and continuous PVAT measurements. The motivation behind the work presented in this paper is to build a real time integrated navigation system using low-cost components available in the market. By using the proper calibration and error estimation techniques such as the extended Kalman filter (EKF), the system can achieve a comparable navigation accuracy with other higher performance navigation system. A linearized north-east-down (NED) error model is adopted, the GPS/INS integration using EKF is described. The algorithm is implemented on a low power ATSAM3X8E ARM Cortex-M3 series microcontrollers and integrated with an on the shelf MEMS 9-DOF IMU. The field experiments results analysis showed an outstanding real-time navigation performance if compared with high performance and much more expensive tactical grade INSs.
为了实现自动驾驶汽车(av)的精确导航解决方案,需要精确测量角速度和线性加速度。惯性测量单元(IMU)被认为是自动驾驶系统中最关键的部件,可以很容易地获得这些测量结果。惯性导航系统包括惯性单元和将惯性单元测量值转换为导航信息(位置、速度、姿态和时间)的复杂过程。为了使用低等级imu来构建可靠的INS,必须实现具有密集辅助滤波器的精确机械化模型,以集成其他传感器,如全球定位系统(GPS)和磁力计,以确保可靠和连续的PVAT测量。本文提出的工作背后的动机是使用市场上可用的低成本组件构建实时集成导航系统。通过适当的校正和误差估计技术,如扩展卡尔曼滤波(EKF),该系统可以达到与其他高性能导航系统相当的导航精度。采用线性化的东北向下误差模型,描述了利用EKF进行GPS/INS集成的方法。该算法在低功耗ATSAM3X8E ARM Cortex-M3系列微控制器上实现,并与现成的MEMS 9自由度IMU集成。现场试验结果分析表明,与高性能、昂贵的战术级ins相比,该系统具有出色的实时导航性能。
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引用次数: 0
Multiphase Interleaved Bidirectional DC/DC Converter for Fuel Cell/Battery Powered Electric Vehicles 用于燃料电池/电池动力电动汽车的多相交错双向DC/DC变换器
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171753
A. Youssef
Transportation relies heavily on fossil fuels. Rapid consumption of natural resources and emission of greenhouse gases due to burning of fossil fuels have prompted the automotive industry to develop sustainable and clean energy sources vehicles for urban transportation. Research and development have been carried out on vehicles driven by electricity generated through renewable sources as possible alternatives to conventional vehicles. Fuel cell electric vehicles (FCEVs) are among these vehicles, which provide a means for an efficient and environmentally friendly urban transportation system. High sensitivity to sudden changes in the loads and poor transient performance issue are the main obstacles for the commercialization of pure fuel cell driven vehicles; therefore, fuel cells are usually augmented with a secondary power source. Typical systems used in industrial vehicles use battery as a secondary power source. Using battery as a secondary power source for FCEVs provides additional peak power in situations such as accelerating and hill climbing, and recuperates braking energy by regeneration, thereby improves the performance and efficiency of the overall system. To manage the energy transfer between batteries and the DC-bus, a converter with bidirectional power flow capabilities is required; therefore, the objective of this paper is to design an appropriate bidirectional DC/DC converter structure or sometimes called an energy management converter to manage the charging and discharging of the battery based on high efficiency range. A multi-phase interleaved bidirectional DC/DC converter structure is proposed, which offers reduction of: input current ripples, stresses on switches, output voltage ripples, and passive component sizes. Improving transient response and reliability are among the many advantages of using such structure.
交通运输严重依赖化石燃料。自然资源的快速消耗和化石燃料燃烧产生的温室气体排放促使汽车行业开发可持续和清洁能源的城市交通工具。研究和开发利用可再生能源发电驱动的车辆,作为传统车辆的可能替代品。燃料电池电动汽车(fcev)就是其中之一,它为高效环保的城市交通系统提供了一种手段。纯燃料电池汽车对负载突变的敏感性高、瞬态性能差是目前纯燃料电池汽车商业化的主要障碍;因此,燃料电池通常增加一个二次电源。工业车辆中使用的典型系统使用电池作为二次电源。将电池作为氢燃料电池汽车的二次动力源,在加速和爬坡等情况下提供额外的峰值功率,并通过再生回收制动能量,从而提高整个系统的性能和效率。为了管理电池和直流母线之间的能量传输,需要具有双向功率流能力的转换器;因此,本文的目标是设计一种合适的双向DC/DC变换器结构,有时也称为能量管理变换器,以实现基于高效率范围的电池充放电管理。提出了一种多相交错双向DC/DC变换器结构,该结构可以减小输入电流纹波、开关应力、输出电压纹波和无源元件尺寸。改善暂态响应和可靠性是采用这种结构的诸多优点之一。
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引用次数: 2
Comparative Analysis between SAR Pulse Compression Techniques SAR脉冲压缩技术的比较分析
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171747
M. Ashry, Ahmed S. Mashaly, B. Sheta
Remote sensing is the backbone for several civilian and military applications. Synthetic Aperture Radar (SAR) is considered as one of the most important tools, which has a significant rule in remote sensing applications. For SAR signal processing, pulse compression techniques aim to obtain a fine map resolution, decrease the peak-transmitted power, and increase Signal to Noise Ratio (SNR) of the sensed target. In this paper, we introduce a performance assessment for two well-known Linear Frequency Modulation (LFM) pulse compression techniques, which are Matching Filtering and Stretch Processing. For matching filtering, it is known as Correlation processing technique. It is mainly used for narrow band and some medium band radar operations. While, stretch processing technique is usually used for high bandwidth LFM signal processing. Besides that, we discuss the properties of the LFM signal and the two compression techniques in both time and frequency domain. Also, the paper investigates the concept of the principle of stationary phase (POSP) and its use in deriving the frequency characteristics for the LFM signal and matched filter output. A mathematical model for each compression technique has been derived such that these models will be used for hardware implementation purpose. For simulation and performance assessment, the two techniques have been analyzed based on some quantitative indices like, Pulse Compression Ratio (PCR) and Peak Side-Lobe Ratio (PSLR).
遥感是一些民用和军事应用的支柱。合成孔径雷达(SAR)是一种重要的遥感工具,在遥感应用中有着重要的作用。在SAR信号处理中,脉冲压缩技术的目的是获得较好的地图分辨率,降低峰值传输功率,提高被测目标的信噪比。本文介绍了两种著名的线性调频脉冲压缩技术的性能评估,即匹配滤波和拉伸处理。对于匹配滤波,称为相关处理技术。主要用于窄带和部分中波段雷达作业。而拉伸处理技术通常用于高带宽LFM信号的处理。此外,我们还讨论了LFM信号的时域和频域特性以及两种压缩技术。此外,本文还研究了固定相位原理的概念及其在LFM信号和匹配滤波器输出的频率特性推导中的应用。每个压缩技术的数学模型已被导出,这些模型将用于硬件实现的目的。为了仿真和性能评估,本文基于脉冲压缩比(PCR)和峰值旁瓣比(PSLR)等定量指标对两种技术进行了分析。
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引用次数: 5
Optimally Weighted Wavelet Variance-based Estimation for Inertial Sensor Stochastic Calibration 基于最优加权小波方差估计的惯性传感器随机标定
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171715
Lionel Voirol, S. Guerrier, Yuming Zhang, Mucyo Karemera, Ahmed Radi
Different inertial sensor calibration techniques have been proposed to consider the sources of measurement error from inertial sensors. There has been a significant amount of literature which studies the stochastic errors calibration of such devices. The recent results of [1] have proved that among all possible methods the (Generalized Method of Wavelet Moments) (GMWM) presents various optimality and is computationally reliable. However, the GMWM estimators depend on weight matrix which considerably impact the quality of the estimated stochastic error models. In addition, such models are made of different components (typically high-frequency and low-frequency components) whose impacts on navigation vary depending on the context. For example, the high-frequency component of the error model may be more important when considering low-cost IMUs mounted on small size drones used for short-term missions. On the other hand, the situation may be reversed when considering navigational grade IMUs used, often autonomously, for long-term missions. With these differences, one may wish to select a GMWM estimator whose weight matrix has been tailored to estimate more reliably the elements of an error model believed to have the greatest impacts on navigation accuracy. In this article, we provide a formal answer to this question by proposing an optimally weighted GMWM estimator. Our results show that the proposed estimator is optimal for all parameters of the sensor error model we wish to estimate with the smallest possible uncertainty of the estimation. Therefore, regardless of the application, and independently of the context, the same optimally weighted estimator can be employed.
为了考虑惯性传感器测量误差的来源,提出了不同的惯性传感器标定技术。目前已有大量文献对此类装置的随机误差校准进行了研究。最近[1]的结果证明,在所有可能的方法中,广义小波矩法(GMWM)具有各种最优性,并且在计算上是可靠的。然而,GMWM估计依赖于权矩阵,这极大地影响了估计的随机误差模型的质量。此外,这些模型由不同的组件(通常是高频和低频组件)组成,它们对导航的影响因环境而异。例如,在考虑安装在用于短期任务的小型无人机上的低成本imu时,误差模型的高频部分可能更为重要。另一方面,当考虑到用于长期任务的导航级imu时,情况可能会相反,通常是自主的。有了这些差异,人们可能希望选择一个GMWM估计器,其权重矩阵已被定制,以更可靠地估计误差模型中被认为对导航精度影响最大的元素。在本文中,我们通过提出一个最优加权GMWM估计器,为这个问题提供了一个正式的答案。我们的结果表明,所提出的估计器对于我们希望以最小的估计不确定性估计的传感器误差模型的所有参数都是最优的。因此,无论应用程序如何,并且与上下文无关,都可以使用相同的最优加权估计器。
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引用次数: 1
Design and Control Strategy of PEM Fuel Cell for a Small Scale Rainwater Harvesting System 小型雨水收集系统PEM燃料电池的设计与控制策略
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171740
H. Farghally, N. Ahmed, A. Nafeh, Emad A. Sweelem, F. Fahmy
This work design a domestic rainwater harvesting system located in Alexandria, Egypt. The considered rainwater harvesting system consists of; roof surface, conveyance system, storage tank and pump. A fuel cell system is used to feed the electrical load of the rainwater harvesting system. Neural Network Controller (NNC) is developed for achieving the desired fuel cell output power and energy management among the fuel cell and the load. A simulation model for the fuel cell has been developed using MATLAB/SMULINK. The evaluation of the controller is based on the time response characteristics of the system. The simulation results show that the system performance under different conditions has been verified using a load demand profile for both constant and step variation loads.
本设计设计了一个位于埃及亚历山大的家庭雨水收集系统。所考虑的雨水收集系统包括;屋顶表面,输送系统,储罐和泵。燃料电池系统被用来供给雨水收集系统的电力负荷。为实现燃料电池输出功率和燃料电池与负载之间的能量管理,开发了神经网络控制器(NNC)。利用MATLAB/SMULINK建立了燃料电池的仿真模型。控制器的评估是基于系统的时间响应特性。仿真结果表明,采用恒负荷和阶跃变负荷的负荷需求曲线,验证了系统在不同工况下的性能。
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引用次数: 1
Design and Implementation of LFMCW Radar Signal Processor for Slowly Moving Target Detection Using FPGA 基于FPGA的LFMCW雷达信号处理器慢动目标检测设计与实现
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171701
Mohamed G Shehata, F. Ahmed, Sameh G. Salem, Hazem Zakaria
Frequency Modulated Continuous Wave (FMCW) radar has extensive areas of application for both civil and military use due to its good performance and detection capabilities. FMCW radar signal processing is based on two main modules; Moving Target Indicator (MTI) and Two-Dimensional Fast Fourier Transform (2D-FFT). Detection performance of FMCW radar is degraded due to the attenuation of the signals come from slowly moving targets with small visible Doppler frequencies. Also, the detection degradation of the targets whose beat frequency do not lie on the FFT grids. These problems have been introduced and overcome. In this paper, a complete design and implementation of LFMCW radar signal processor incorporating the solution of these problems are introduced on a field programmable gate array (FPGA) to facilitate real time processing. Simulation and experimental measurement are found to be identical illustrating the capability of the applied methods. The hardware implementation includes generation of the digital sawtooth waveform, Dechirping process,2D_FFT processing, Windowing, MTI, Single Delay Line Integrator and off pin filter.
调频连续波雷达(FMCW)由于其良好的性能和探测能力,在民用和军用领域有着广泛的应用。FMCW雷达信号处理主要基于两个模块;运动目标指示器(MTI)和二维快速傅里叶变换(2D-FFT)。由于多普勒可见频率较低的慢动目标信号的衰减,使得FMCW雷达的探测性能下降。此外,对于拍频不在FFT网格上的目标,其检测性能也会下降。这些问题已经提出并克服了。本文针对这些问题,在现场可编程门阵列(FPGA)上实现了LFMCW雷达信号处理器的完整设计和实现,以方便实时处理。仿真结果与实验测量结果一致,说明了所采用方法的有效性。硬件实现包括数字锯齿波形的生成、解码处理、2D_FFT处理、加窗、MTI、单延迟线积分器和关脚滤波器。
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引用次数: 1
Robust H-infinity Controller for a Single-axis Spacecraft Rotation 航天器单轴旋转鲁棒h∞控制器
Pub Date : 2020-07-01 DOI: 10.1109/ICEENG45378.2020.9171723
Aya B. Elghonemy, A. El-Badawy
This paper focuses on the problem of robust H-infinity control design for a linear uncertain SISO system represented as a single-axis spacecraft rotation. The parametric uncertainty and disturbance input make this control problem a challenge. The paper presents an H-infinity control design which stabilizes all possible perturbed plants within the system and guarantees disturbance attenuation and meeting the tracking specifications while maintaining practical controller gains for all admissible uncertainties. The paper includes a design of a PD controller on the single-axis spacecraft plant and a comparison between the two controllers under the effect of disturbance and uncertainty. The robust H-infinity control problem is formulated into the General control problem formulation then solved via DK-iterations which is based on the concepts of H-infinityoptimization and μ-synthesis. The synthesized robust H-infinity controller is verified by nominal stability analysis, nominal performance analysis, robust stability analysis, robust performance analysis and worst case gain analysis, in addition to, testing the controller’s performance specifications.
研究了以航天器单轴旋转为代表的线性不确定SISO系统的鲁棒h∞控制设计问题。参数的不确定性和干扰输入使控制问题成为一个挑战。本文提出了一种h∞控制设计,该设计稳定了系统内所有可能的扰动对象,并保证扰动衰减和满足跟踪规范,同时对所有允许的不确定性保持实际控制器增益。本文设计了一种单轴航天器控制系统的PD控制器,并对两种控制器在干扰和不确定性影响下的性能进行了比较。基于h -∞优化和μ-综合的概念,将鲁棒h -∞控制问题转化为一般控制问题,通过dk -迭代求解。通过标称稳定性分析、标称性能分析、鲁棒稳定性分析、鲁棒性能分析和最坏情况增益分析对所设计的综合鲁棒h∞控制器进行了验证,并对控制器的性能指标进行了测试。
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引用次数: 1
期刊
2020 12th International Conference on Electrical Engineering (ICEENG)
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