Hysteresis compensation of piezoelectric actuator for open-loop control

The hysteresis nonlinearity of piezoelectric actuator is one of the main defects in the control of deformable mirror which is widely used as a key component in adaptive optics system. This letter put forward a roodified Prandtl-Ishlinskii （PI） model in order to precisely describe the hysteresis nonlinearity of piezoelectric actuator. With this proposed model, an inverse-model based controller used for trajectory tracking in open-loop operation is designed to compensate the hysteresis nonlinearity effect. Then, some tracking control experiments for the desired triangle trajectory are performed. From the experimental results, we can see that the positioning precision in open loop operation is significantly improved with this inverse-model based controller.     

Trigger design for a gamma ray detector of HIRFL-ETF

The Gamma Ray Array Detector (GRAD) is one subsystem of HIRFL-ETF (the External Target Facility (ETF) of the Heavy Ion Research Facility in Lanzhou (HIRFL)). It is capable of measuring the energy of gamma-rays with 1024 CsI scintillators in in-beam nuclear experiments. The GRAD trigger should select the valid events and reject the data from the scintillators which are not hit by the gamma-ray. The GRAD trigger has been developed based on the Field Programmable Gate Array (FPGAs) and PXI interface. It makes prompt trigger decisions to select valid events by processing the hit signals from the 1024 CsI scintillators. According to the physical requirements, the GRAD trigger module supplies 12-bit trigger information for the global trigger system of ETF and supplies a trigger signal for data acquisition (DAQ) system of GRAD. In addition, the GRAD trigger generates trigger data that are packed and transmitted to the host computer via PXI bus to be saved for off-line analysis. The trigger processing is implemented in the front-end electronics of GRAD and one FPGA of the GRAD trigger module. The logic of PXI transmission and reconfiguration is implemented in another FPGA of the GRAD trigger module. During the gamma-ray experiments, the GRAD trigger performs reliably and efficiently. The function of GRAD trigger is capable of satisfying the physical requirements.     

Control of Unknown Chaotic Systems Based on Neural Predictive Control

We introduce the predictive control into the control of chaotic system and propose a neural network control algorithm based on predictive control. The proposed control system stabilizes the chaotic motion in an unknown chaotic system onto the desired target trajectory. The proposed algorithm is simple and its convergence speed is much higher than existing similar algorithms. The control system can control hyperchaos. We analyze the stability of the control system and prove the convergence property of the neural controller. The theoretic derivation and simulations demonstrate the effectiveness of the algorithm.     

Tracking Desired Trajectory in a Vibro-Impact System Using Backstepping Design

Based on the backstepping design of smooth systems, we developed a new control law to achieve chaos control for a vibro-impact system. In our control strategy, a novel and effective controller is designed such that the output of the vibro-impact system can track any desired trajectory in its domain. The single-degree-of-freedom vibro-impact system is taken as an example to show this control procedure. Numerical simulations are provided to verify the effectiveness of the proposed method.     

Synchronization Scheme for Uncertain Chaotic Systems via RBF Neural Network

A sliding mode adaptive synchronization controller is presented with a neural network of radial basis function （RBF） for two chaotic systems. The uncertainty of the synchronization error system is approximated by the RBF neural network. The synchronization controller is given based on the output of the RBF neural network. The proposed controller can make the synchronization error convergent to zero in 5s and can overcome disruption of the uncertainty of the system and the exterior disturbance. Finally, an example is given to illustrate the effectiveness of the proposed synchronization control method.     

Timing system of HIRFL-CSR

The national science project HIRFL-CSR has recently been officially accepted. As a cyclotron and synchrotron complex, it puts some particularly high demands on the control system. There are hundreds of pieces of equipment that need to be synchronized. An integrated timing control system is built to meet these demands. The output rate and the accuracy of the controller are 16 bit/μs. The accuracy of the time delay reaches 40 ns. The timing control system is based on a typical event distribution system, which adopts the new event generation and the distribution scheme. The scheme of the timing control system with innovation points, the architecture and the implemented method are presented in the paper.     

Synchronization between two different chaotic systems with nonlinear feedback control

This paper presents chaos synchronization between two different chaotic systems by using a nonlinear controller, in which the nonlinear functions of the system are used as a nonlinear feedback term. The feedback controller is designed on the basis of stability theory, and the area of feedback gain is determined. The artificial simulation results show that this control method is commendably effective and feasible.     

Notch filter feedback controlled chaos in buck converter

A method of controlling chaos in the voltage-mode buck converter is presented by using an improved notch filter feedback control in this paper. The proposed control part comprises a notch filter and a low-pass filter. The discrepancy between the outputs of the two filters is introduced into the control prototype of the power converter. In this way, the system period-1 solution is kept unchanged. The harmonic balance method is applied to analysing the variation law of the system bifurcation point, and then the stable range of the feedback gain is ascertained. The results of simulation and experiment are also given finally.[第一段]     

A single adaptive controller with one variable for synchronization of fractional-order chaotic systems

In this paper we investigate the synchronization of a class of three-dimensional fractional-order chaotic systems.Based on the Lyapunov stability theory and adaptive control technique,a single adaptive-feedback controller is developed to synchronize a class of fractional-order chaotic systems.The presented controller which only contains a single driving variable is simple both in design and in implementation.Numerical simulation and circuit experimental results for fractional-order chaotic system are provided to illustrate the effectiveness of the proposed scheme.     

Security of Operation on CSR Control System

It is important to the security of operation on the CSR control system. In order to keep the CSR control system in security environment, the following work has been done. Firstly, it can be set up a domain service, and every important services can join in it, such as databasese rvices, front web services and every interactive operating browsers, and limited the browsers right by using policy of the domain. After this, the browsers can‘t modify the setting of the browser, and it can keep every computers and browsers in security by preventing some virus into each computer. The domain services of control system is shown in Fig.1.     

超长周期慢引出主环磁铁电源控制系统设计

介绍了兰州重离子加速器冷却储存环（HIRFL-CSR）超长周期慢引出主环（CSRm）磁铁电源控制系统的设计。该系统采用基于高速以太网的分布式控制系统,选用了ARM+DSP结构的前端智能控制器,对整个运行周期的控制采用了分段处理的机制,解决了波形数据量过大而无法在前端控制器进行全波形存储的问题。该系统已经在加速器冷却储存环中通过了调试,满足了物理实验的要求。     

用于重离子加速器磁铁电源的数字调节器设计

 介绍了兰州重离子加速器冷却储存环上采用高级RISC微处理器(ARM)+现场可编程门阵列(FPGA)+DA/AD技术、状态空间方程方法实现对磁铁电源系统数字调节器的设计,它可以实现5阶及以下各阶的调节控制。运用ARM作为调节控制系统的核心处理器,完成系统的多线程任务处理。电源的精度调节通过FPGA和DA/AD相结合的技术来实现,通过千兆光纤接口实现外接数字信号处理器输入信号的直接传输。同时通过光电隔离器对叠加在输入/输出32 bit数字状态量的干扰脉冲进行抑制。经现场测试该调节器达到了加速器电源系统1×10^-4量级的精度要求,并减少了电源系统的故障恢复时间。     

兰州重离子加速器冷却存储环控制系统

为了完成建设兰州重离子加速器冷却存储环,自主研发设计了其大型分布式控制系统。控制系统从功能上分为三层:业务管理层、前端控制层以及设备控制层。业务管理层主要包含控制管理程序、中心数据库以及同步时间系统;前端控制层主要包含前端服务器、前端控制器以及各其他控制器等;设备控制层主要为微控制单元 (MCU)多功能控制器以及被控设备等。其中中央数据库存储整个加速器的所有控制数据,为变能时控制系统的控制数据切换提供数据支持。从长期运行情况来看,控制系统需要进行相应的改进,但是能基本满足现行的实验需求。     

基于ARM的激光式大坝水平位移监测系统

针对大坝安全监测的技术要求,设计并研制了一套基于铅垂线原理的大坝水平位移测量系统。该系统以光栅尺、激光发射和接收器、减速电机为主要运动部件,以性能强大的ARM内核芯片为主控制器,采用大屏幕LCD为人机交互界面,实现对大坝水平横向和纵向的精确测量。该系统还具有人工手动实时测量、定时自动测量的功能,可以通过485总线上传测试结果到总控制中心进行显示和分析。实验结果表明,该系统具有精度高、成本低、误差小的优点。     

基于BU-61580总线控制器的接口及容错设计

针对RS-422接口与1553B总线接口无法直接进行高可靠性数据通信,提出了一种基于BU-61580总线控制器的接口及容错设计。设计采用1553B接口芯片BU-61580,通过FPGA控制完成了RS-422与1553B的接口控制及二者之间的数据处理。在硬件接口设计的基础上,设计IP-CORE完成BU-61580的芯片配置,并通过增加容错设计提高了总线控制器数据通的可靠性。经测试结果显示,计算机通过总线控制器与RT终端通信稳定、可靠,并应用于某测试系统中。     

基于OMAPL138 FPGA构架的PC104主板检测系统

为了对PC104主板进行自动检测,分析了PC104主板工作原理及其总线时序,提出了一种基于ARM FPGA的嵌入式检测系统的设计方案。该方案采用德州仪器(TI)双核架构的高性能芯片OMAPL138中的ARM核来实现检测系统的应用管理,DSP核实现数据的处理,并利用FPGA技术来实时采集PC104总线数据。检测系统在Linux操作系统下,通过人机交互方式实现了PC104主板的各种功能的自动检测。实验结果显示该检测快速可靠,为PC104主板的自动检测提供了一种有效的方法。     

实时主动声定位系统设计*

针对在军事演习或爆炸实验中对冲击波超压传感器位置的精确定位,设计了一种实时主动声定位系统。该系统由声信号发射系统、声信号接收处理系统和无线监控终端系统三部分组成。声信号发射系统与无线监控终端以单片机STC12C5A60S2作为核心控制器,接收处理系统以ARM9系列的S3C2440作为核心控制器。发射系统发射四种已知频率的声信号,接收处理系统接收并处理收到的四种声信号,然后把处理结果反馈到无线监控终端。通过实验表明,该系统在一定条件下,能够稳定地发射、接收并处理声信号,达到实时定位目标,并在200 m范围内将定位误差控制在厘米级内。     

HIRFL-CSR故障诊断报警电路设计

针对兰州重离子加速器冷却储存环(HIRFL-CSR)复杂的现场环境和对现场故障精确检测报警的迫切需求,以TI公司的MSP430混合信号处理器为核心,采用负反馈电路稳定工作点,并结合RS-485现场总线技术完成了故障诊断报警电路的设计。结果表明:该诊断报警电路具有稳定性好、灵敏度高、耗电量小、价格低、使用方便、定位精确的优点,适合各种复杂的工作环境,可广泛应用于开关量诊断报警。现已成功应用于HIRFL-CSR漏水检测报警系统中。     

LON仿人思维控制器设计与实现

新型智能控制仪表的发展趋势是基于人工智能，人工智能在控制领域的应用核心是模拟人的控制智慧。LON仿人思维控制器是基于LonWorks总线的智能控制器，模拟了人的控制思维与智慧，体现了仿人思维控制理论与方法研究成果。控制器采用双CPU设计，将嵌入式技术与LonWorks总线技术有机结合在一起，可以实现模拟信号、开关信号及其脉冲信号的输入、输出，可与其它控制仪表实现RS-232、USB、LonWorks总线通讯。LON仿人思维控制器集成了独有的仿人思维控制算法，既可以单独使用，也可以构成拟人化分布式智能控制系统。实验结果表明，LON仿人思维控制器对温度、压力、流量、液位等过程工业物理量有很好的控制效果。     

兰州重离子加速器冷却存储环慢引出控制系统

兰州重离子加速器冷却存储环为了进行深层重离子治疗肿瘤的实验,需要长时间、均匀地慢引出束流至高能束运线,以满足深层重离子治疗肿瘤的束流要求。慢引出控制系统采用加速器控制系统的同步时间信号来进行同步控制以实现整个过程控制;当加速器控制系统的同步事例的同步触发信号进行触发控制以及数据切换（频率值、tune值、电压幅值）,波形发生器通过这三个数据信息产生相应的波形及进行放大器放大并控制静电偏转板以实现束流RF-KO方式慢引出。慢引出控制系统的同步事例接收器主要由FPGA与光纤接口组成,实现同步事例的高速稳定传输与强抗干扰性。深层重离子治疗肿瘤的正常运行以及冷却存储环已实现104 s超长周期的慢引出实验表明,慢引出控制系统能实现实验束流需求的慢引出。