一种降低核间通信开销的调度算法

近年来,多核处理器在嵌入式领域得到越来越广泛的应用,但多核间不可避免的通信开销阻碍了系统性能大幅提升,因此研究如何降低核间通信开销变得尤为重要. 针对同构多核平台上周期依赖任务,提出一种降低核间通信开销的任务调度算法并在该基础上进行优化,通过对部分任务预先调度一个周期,将周期内任务间的数据依赖转换成周期间的数据依赖,从而缩短调度长度,提高系统性能. 对以上算法进行仿真模拟,并分别在双核和四核平台上进行多组实验. 结果表明：提出的调度优化算法可以显著降低周期依赖任务核间通信开销,提高执行效率.     

企业集散控制系统总线型控制器的设计

本文设计了适用于中小型企业的集散控制系统中控制器部分.主要介绍了该控制系统的整体架构,研制了现场控制器的硬件系统.控制网络系统采用三层结构,核心是直接控制工业过程的现场控制层.现场控制层主控制器采用模块化设计方式,模块之间采用总线互连.主控制CPU选用的是高性能的32位嵌入式ARM核处理器芯片,模块间通信总线选用SMBus串行总线.     

一种适应多核处理器核间通信机制的设计

随着单芯片上集成处理器内核数量的增加,在支持多核处理器的应用程序方面,核间通信变得更加重要.通过分析多核运行任务特点,根据处理核上运行任务功能的不同,将处理核分成两类:控制核和计算核.根据对核的分类,提出了一种新的核间通信模型,该模型提供了三种不同的通信通道.运用这三条通道,把应用程序的I/O部分从计算核迁移到控制核来提高多核的利用率,实验结果表明该方式有效提高核间协作以及核间通信的效率,提升处理器的利用率.     

异构双核处理器失速告警系统设计

失速会影响飞机飞行安全。传统的失速告警系统虽然通过采用多处理器同步时钟的方法提高了安全性,但系统可靠性降低且复杂度变高。为提升失速告警系统的可靠性、降低失速告警系统的复杂度,采用异构双核处理器所具备的核间数据交互和数据一致性检查功能来实现失速告警系统的高安全性设计。首先,依据总体设计选择合适的处理器。然后,根据所选的异构双核处理器对核间通信机制进行对比选择。最后,对双核数据传输任务进行合理分配。测试结果表明,利用双核处理器中的共享内存通信机制进行数据传输,数据的传输交互更加安全、快速和高效。通过对解算数据在同一处理器进行一致性检查的方法,提高了输出指令的正确率,提升了系统的安全性能,满足了失速告警系统对于高可靠性、高安全性的要求。此外,选用异构双核处理器进行余度设计同样适用于其他类型系统。     

基于多核任务并行处理的DSP软硬件设计

多核处理器的软件和硬件设计从传统的任务串行到任务并行处理,与单核处理器软硬件设计区别较大。本文以8核DSP芯片TMS320C6678为例,介绍了多核DSP的系统结构、多核处理器的任务分割和任务分配到各个核的方法、多个核之间的任务管理和核间通信,以及基于多核导航器的硬件设计方法。     

OMAP L138核间通信高吞吐量图像处理平台及应用

异构双核芯片 AMR+DSP具有强大的任务管理、人机交互和数据处理功能,为嵌入式图像处理领域提供了一种新的架构。为了减少开发人员对底层驱动的设计,TI 研发了 Syslink 驱动用于核间通信,包括 Notify、MessageQ 协议等,其中基于 MessageQ的通信协议常用于核间图像传输,但其占用资源较多、延迟高。本文对 TI 公司的达芬奇架构OMAP L138处理器的多核通信理论进行研究,利用核间中断寄存器和共享内存队列存储机制进行数据交互,实现了一种高吞吐量的图像处理平台。     

基于多核DSP的超声成像处理算法的并行实现

基于TI公司的多核DSP-TMS320C6678对黑白超声成像的中端(Mid-End)处理算法进行并行设计与实现。介绍了多核DSP编程实现算法所用到的关键技术:程序并行设计与第三代增强型直接内存存取(EDMA3),并重点分析了核间通信技术。根据算法的特点选用数据流模式对其进行了任务规划并分配到3个DSP核上执行,核间通信采用消息队列方案。实验结果证明了采用消息队列方案进行核间通信、实现多核并行的有效性。     

多核嵌入式系统内联网络优化调度

处理核之间的通信问题是多核系统中不可避免的问题,根据具体应用,进行核间内联网络的定制和设计是一个可行的研究方向。针对该问题提出了任务节点的通信调度算法,通过采用点对点连接作为内联网络的方式,在不增加系统调度长度的前提下,构造出满足系统核间通信需求、核间点对点连接数最少的内联网络。同时还给出了核间通信调度确定算法和内联网络构造算法,为内联网络的设计提供依据。实验表明,与传统的HLFET算法相比,提出的调度算法能极大减少嵌入式系统中的核间点对点连接数目。     

TMS320C6678多核DSP的核间通信方法

嵌入式应用中采用多处理系统所面临的主要难题是多处理器内核之间的通信。对Key-Stone架构TMS320C6678处理器的多核间通信机制进行研究,利用处理器间中断和核间通信寄存器,设计并实现了多核之间的通信。从系统的角度出发,设计与仿真了两种多核通信拓扑结构,并分析对比了性能。对设计多核DSP处理器的核间通信有一定的指导价值。     

基于ARM的光电伺服控制器设计

介绍了某望远镜伺服控制系统的控制器设计,控制器以ARM LPC2478为核心控制器芯片,以CPLD EPM570T144为功能扩展控制芯片实现对望远镜系统的多轴控制.给出了控制器的软硬件设计方案,并利用光电伺服转台测试控制器的性能,实验结果表明基于ARM设计的光电伺服控制器能够达到满意的控制效果,系统上升时间快、稳态误差小、无超调,能够满足望远镜系统对多轴控制的需要.     

Adaptive control of a 3-DOF parallel manipulator considering payload handling and relevant parameter models

Model-based control improves robot performance provided that the dynamics parameters are estimated accurately. However, some of the model parameters change with time, e.g. friction parameters and unknown payload. Particularly, off-line identification approaches omit the payload estimation (due to practical reasons). Adaptive control copes with some of these structural uncertainties. Thus, this work implements an adaptive control scheme for a 3-DOF parallel manipulator. The controller relies on a novel relevant-parameter dynamic model that permits to study the cases in where the uncertainties affect: (1) rigid body parameters, (2) friction parameters, (3) actuator dynamics, and (4) a combination of the former cases. The simulations and experiments verify the performance of the proposed controller. The control scheme is implemented on the modular programming environment Open Robot Control Software (OROCOS). Finally, an experimental setup evaluates the controller performance when the robot handles a payload.     

Robustness of decentralized robot controller to payload variation

The decentralized controller for manipulation robot is tested for its robustness to payload variation. First the local controllers are synthesized to withstand variation of inertia round the joints and then the global stability of the robotic system is examined. Three various situations are discussed: a) when actuator inertia is large in comparison to mechanism inertia, b) if the variation of payload is small in comparison to mechanism inertia, and c) if the large variation of payload parameters are expected. An algorithm for testing the robustness of the robot control to parameter variation is established, too. The purpose of the algorithm is to determine the allowable variation of the payload parameters which can be withstood by the simple decentralized controller. On the other hand, by this algorithm the local servosystems can be synthesized which are capable to withstand assumed parameter variation. This synthesis is demonstrated on an example of particular robotic system.     

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信的可靠性;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。     

Nonlinear Anti-swing Control of Underactuated Tower Crane Based on Improved Energy Function

The control system of tower crane exhibits strong nonlinearity in the process of control execution, which is prone to the problems of inaccurate positioning control of the payload and difficult anti-swing control. Aiming at the problems, this paper proposes a control law based on improved energy coupling analysis for suppressing the payload swing in the tower cranes. A three-dimensional dynamic model of tower crane system with considering friction is established, and an improved energy coupling signal is designed. The coupling relationship of trolley movement and payload swing, jib rotation and payload swing are considered, then a nonlinear anti-swing controller is established in order to reduce the swing. The closed-loop stability of the system with the controller is verified by the Lyapunov method and LaSalle invariance principle, simulations and experimental analyses are performed to verify the controller performance. The control performance of the controller is compared with other classic and typical current control methods, and the proposed controller outperformed other controllers. The anti-swing controller proposed in this paper has accurate positioning, and can achieve precise control when the payload is transported, reaching the set target position in a little time and eliminating residual swing angle. Meanwhile the proposed controller has a good control robustness, which can restore stability in around a very short time when the rope length and payload mass of the system’s inherent property are changed and external interference is added. In addition, when different target position parameters are uncertain, the proposed control law has good robust performance.

     

温枪弹道中光电靶灵敏度控制系统优化设计

传统控制系统存在灵敏度控制效果差、性能不稳定等问题,无法满足高效控制标准,提出温枪弹道中光电靶灵敏度控制系统优化设计。根据实际条件和干扰元素设计原理,从温枪弹道中光电靶灵敏度控制角度出发,将光信号转换为微弱电流信号,对微弱电流信号进行转换,设计光电靶灵敏控制器和光电转换电路,完成系统硬件部分设计;选择基于优化环境下的软件程序开发板来实现软件编程,完成光电靶灵敏度控制系统的优化。实验验证结果可知,该系统灵敏度控制效果强、性能稳定。     

Fractional-order integral resonant control of collocated smart structures

This paper proposes a fractional-order integral controller, FI, which is a simple, robust and well-performing technique for vibration control in smart structures with collocated sensors and actuators. This new methodology is compared with the most relevant controllers for smart structures. It is demonstrated that the proposed controller improves the robustness of the closed-loop system to changes in the mass of the payload at the tip. The previous controllers are robust in the sense of being insensitive to spillover and maintaining the closed-loop stability when changes occur in the plant parameters. However, the phase margin of such closed-loop systems (and, therefore, their damping) may change significantly as a result of these parameter variations. In this paper the possibility of increasing the phase margin robustness by using a fractional-order controller with a very simple structure is explored. This controller has been applied to an experimental smart structure, and simulations and experiments have shown the improvement attained with this new technique in the removal of the vibration in the structure when the mass of the payload at the tip changes.     

嵌入式SoC中键盘控制器的设计与实现

“龙腾”S1是以工业控制应用为背景的高性能嵌入式SoC，键盘控制器为其整个键盘系统提供硬件基础。本文详细分析了键盘系统的工作机制，给出了一种键盘控制器的设计结构和控制时序，通过优化某些具体电路增加设计的可重用性和可验证性。最后经过FPGA验证，证明该设计完全支持通用的PS／2键盘，在时序和功能上满足了设计要求。     

A parallel fuzzy-controlled flexible manipulator using optical tip feedback

Investigation and development of a fuzzy-controlled highly non-linear two-axis manipulator with a single-flexible link using a novel patented optical tip displacement feedback is described. The controller comprises a parallel fuzzy supervisor that is used to alter the derivative term of a linear classical PD controller, which is updated in relation to the measured tip error and error rate.Implementation of the supervisory fuzzy controller is described using both serial and parallel operation on transputers.The design of the fuzzy rules was made with a modified closed-loop phase-plane method. The design approach results in a controller implementation that uses only 14 rules and is suitable for cheaper CPU-constrained and memory-challenged embedded processors.The benefits introduced by this procedure include a method to decide where and when the action takes effect in the controller and a greatly reduced rule base. The parallel operation achieved rise times of 0.033 s and settling times of 0.064 s for a payload of 0.7 kg considerably better than other workers did.An 128% increase in payload, 73.5% faster settling time and a reduction of steady-state error of over 50% were achieved using fuzzy control over its classical counterpart.     

机载光电稳瞄平台的扰动观测分数阶控制方法

随着机载光电稳瞄平台在国防军事领域的广泛应用,现代武器系统对机载光电稳瞄平台控制技术的要求越来越高.鉴于此,结合分数阶控制和扰动观测器原理,提出一种基于扰动观测的分数阶控制方法,用于提高机载光电稳瞄平台控制系统的各项性能.给出相应的闭环控制系统结构和控制器设计方法,并对其输入输出特性、扰动抑制能力等性能进行研究.在阶跃响应、正弦跟踪、扰动抑制和鲁棒性等仿真实验中,所提出控制器均表现良好.仿真结果表明,所提出基于扰动观测的分数阶控制器不仅具有分数阶控制响应速度快、鲁棒性强的特性,还表现出扰动观测器抗扰能力强的优点,可以达到提高机载光电稳瞄平台控制系统性能的目的.