Synthesis of a linearly interpolated gain scheduling controller for large flexible spacecraft ETS-VIII

This paper illustrates a design procedure for a linearly interpolated gain scheduling controller for Engineering Test Satellite VIII (ETS-VIII) using its linear parameter-varying (LPV) model. The LPV model here consists of piecewise-linear functions of the paddle rotation angle and a norm-bounded perturbation. The main purpose of this research is to derive a simple structured scheduling law that can be easily implemented in a satellite onboard computer. The derived gain has only two grid points and is scheduled simply by linear interpolation, which is desirable from the standpoint of implementability. Moreover, since the synthesis condition is based on parameter-dependent Lyapunov functions, it gives less conservative results than existing methods. Simulation results are presented to show the effectiveness of the proposed synthesis.     

Energy-based robust controller design for flexible spacecraft

This paper presents a class of non-model2based position controllers for a kind of flexible spacecraft. With the controllers, one can achieve not only the closed-loop stability of the original distributed parameter system, but also the asymptotic stability of the truncated system, which is obtained through representing the deflection of the appendage by an arbitrary finite number of flexible modes. The system dynamics are not explicitly involved in the controller design and stability proof. Instead, only a very basic system energy rehtionship of the flexible spacecraft is utilized. The controllers possess several remarkable advantages over the traditional model-based ones. Numerical simulations are carried out on a kind of spacecraft with one flexible appendage and satisfactory results are obtained.     

刚体航天器姿态跟踪的高阶滑模控制器设计

针对存在参数不确定性和外加干扰的刚体航天器的姿态跟踪控制问题,提出一种基于高阶滑模的姿态跟踪控制方法．首先介绍高阶滑模控制的基本原理,并建立基于修正罗德里格参数描述的航天器数学模型;然后采用李雅普诺夫第２法推导出高阶滑模姿态控制律．理论分析和仿真结果均表明,该方法能够有效消除系统抖振,实现航天器姿态跟踪的精确定位,并且系统具有全局稳定性和鲁棒性．     

A non-linear spacecraft attitude tracking controller for large non-constant rate commands

A new non-linear tracking control algorithm based on an attitude error quaternion is studied in this paper. The control law developed here uses the commanded attitude rate without transformation into the body frame. The direct use of the commanded attitude rate simplifies the calculation of its derivative, which is used in the control law. The solutions and the equilibrium points of the closed-loop system, which is a time-varying non-linear system, are obtained in different scenarios. In order to analyse the stability of the system and the tracking performance, two different forms of perturbation dynamics with seven state variables are introduced. Local stability and performance analysis shows that the eigenvalues of the linearized perturbation dynamics are determined only by the gain matrices in the control algorithm and the inertia matrix. The existence of globally stable tracking control is proved using a Lyapunov function. Simulation results show that the spacecraft can track the commanded attitude and rate quickly for a non-zero acceleration rate command.     

A simple velocity-free controller for attitude regulation of a spacecraft with delayed feedback

In this note, we consider the application of a velocity-free controller for attitude regulation of a rigid spacecraft with gas jet actuators when the effects of time-delays in the feedback loop are taken into consideration. Simple sufficient conditions for exponential stability are presented. Some structural properties of the resulting closed-loop system are studied, and relevant design tools are demonstrated.     

Neural network-based robust finite-time attitude stabilization for rigid spacecraft under angular velocity constraint

Neural Computing and Applications - In this paper, the problem of attitude stabilization control of spacecraft under angular velocity constraint is investigated. A state-constrained finite-time...     

液压控制器的设计与实现

液压控制器是一种具有控制精度高、响应速度快和输出功率大特点的控制元件,具有极高的应用价值,可广泛应用到诸多领域中.当前,液压控制器在具体的使用中,存在处理高速与低速设备的速度匹配问等问题,影响液压控制器的应用.故此,文章选择模块化设计方式、高速处理速度DSP为核心控制芯片、丰富通讯接口、4轴驱动能力等技术措施,进一步完...     

Output attitude tracking for flexible spacecraft

In this work a class of nonlinear controllers has been derived for spacecraft with flexible appendages. The control aim is to track a given desired attitude. First, a static controller based on the measure of the whole state is determined. Then, a dynamic controller is designed; this controller does not use measures from the modal variables, and the variables measured are the parameters describing the attitude and the spacecraft angular velocity. Finally, it is shown that a relaxed version of the tracking problem can be solved when the only measured variable is the spacecraft angular velocity. Simulations show the performances of such control schemes.     

Design of an on-line controller for microcomputer implementation

An on-line controller is developed for the regulation of d.c. compound motors using microcomputer capability. The controller has a PID configuration, the parameters of which are computed using linear-quadratic theory. Procedures for selecting the sampling period, software design, and hardware specification are presented.     

ITS嵌入式控制主机的设计与实现

针对交通行业的发展需要,提出了以嵌入式主板为核心的ITS嵌入式控制主机的设计及实现方案。在为支持多路车检器和多路高清相机同时工作,实现了多车道车流量监测、过车抓拍、逆行抓拍、超速抓拍、压黄线抓拍、车辆测速等功能,同时实现了智能交通前端设备的自我保护、自我检测和远程监控等功能。     

Nexperia平台JTAG控制器设计与实现

描述了一种针对Nexperia多媒体平台PNX1300/PNX1500系列DSPCPU的PCI接口的JTAG控制器设计和实现。重点介绍JTAG接口标准,工作原理及其JTAG控制器的电路设计和程序设计,已实际应用在基于PNX1300的嵌入式系统调试中,取得了很好的效果。     

船舶航向的鲁棒自适应控制器的设计和仿真

针对带参数不确定性,未知有界扰动及未建模动态的船舶航向跟踪控制问题,本文介绍了一种鲁棒自适应算法。此算法能保证系统的全局稳定,使闭环系统的所有变量一致有界。并通过仿真对两种算法进行比较,可以看出,依照本文算法设计的控制器具有很好的鲁棒性。     

非线性时滞系统鲁棒L2控制器设计

本文针对带有不确定性的非线性时滞系统,基于系统耗散的定义,讨论了其鲁棒L2控制器设计问题,通过设计一个新的李雅普诺夫泛函,得到了系统稳定且满足耗散的充分必要条件,在此基础上设计满足L2性能指标的控制器,所得结果通过线性矩阵不等式给出.     

SATA2.0控制器的设计与实现

SATA2.0传输标准以速度高、抗干扰等优点而成为高速大容量存储介质硬盘的数据传输标准。由于主机端是软件控制,导致以FPGA为代表的部分电子系统鉴于上述原因而无法使用SATA2.0硬盘作为数据存储介质。对上述问题展开研究,针对FPGA开发中对数据的存储需求并结合最新的高速串行收发器设计了一款基于FPGA的SATA2.0控制器。经测试该设计能够准确读取设备端数据,具有良好工作的稳定性。     

PCI总线目标控制器的设计与实现

比较了目前两种主流PCI目标接口的实现方式——使用CPLD／FPGA或者专用电路，分析了PCI目标控制器的接口和实现的功能，介绍了控制器的内部结构和控制逻辑以及如何对PCI主设备发起的操作做出响应。介绍了整个设计的仿真和验证，验证结果表明设计符合PCI局部总线规范。     

新型高分辨率LCD控制器的设计与实现

为了解决ARM等嵌入式处理器驱动大屏幕LCD困难的问题,提出了一种基于FPGA的大屏幕LCD控制器解决方案.该控制器通过搭建合理的架构设计及巧妙的总线仲裁机制,解决了大屏幕显示所需的高刷新率和高更新率问题.同时,多个内部寄存器使其支持各种型号的LCD显示器,并成功地驱动了15英寸的LCD显示器.     

一种穿戴式系统电源控制器设计与实现

设计了一种穿戴系统电源控制器,是基于单片机控制的电源控制器,为穿戴式系统提供电源管理功能。具有双电池的充电/供电管理,内置单片机,电源开关软控制,并可遥控关机,可实时监控并指示控制器各工作状态,可指示电池电量信息,与上位机通信上传工作状态及电池电量等信息。具有充满保护、过流保护、短路保护、输入反接保护、双电池并接工作等保护功能。具有效率高、体积小、操作简单、功能全、双电池配置灵活、金属外壳电磁兼容性好、可靠性高等优点。可以用太阳能电源或手摇发电机通过控制器给电池充电,提高其野外使用适应性。     

HDLC协议控制器IP核的设计与实现

介绍了HDLC协议控制器的IP核方案及实现方法,分别对发送和接收模块进行了分析,给出了仿真波形图。该设计采用Verilog HDL语言进行描述,用ModelSim SE 6.0进行了功能仿真。     

一种姿态测量系统的FPGA和DSP设计与实现

为了实现对某弹载系统的姿态测量,提出一种基于FPGA+DSP的姿态测量系统的设计.系统采用FPGA作为逻辑控制核心,完成对MEMS传感器输出的陀螺加表数据的采集,并通过EMIF接口完成与DSP的数据通信.DSP完成对姿态信息的解算,并由FPGA通过RS422接口将更新后的姿态信息上传至上位机.系统选用地理坐标系作为导航...     

Finite-time attitude quantised control for rigid spacecraft

This paper investigates the quantised finite-time attitude control for rigid spacecraft in the presence of external disturbance. First, a novel quantiser is designed with the combination and improvement of the traditional hysteresis logarithmic quantiser and hysteresis uniform quantiser, so that the innovative quantiser in this paper has the advantages of both hysteresis and uniform quantisers in ensuring chattering free and acceptable quantisation errors for better transient and steady-state performances. Second, a finite-time controller is synthesised even under disturbances and quantisation errors, and the closed-loop system/state converges to the region near zero in finite time. Finally, the attitude stabilisation and attitude tracking simulation results for the rigid spacecraft are presented to illustrate the effectiveness and feasibility of the proposed control strategy.