使用角度定时器的电容放电点火控制

传统电容放电点火(CDI)的数字控制采用定时器、捕捉比较模块实现。其将激励角度转换为相应的定时器计数值,采用普通16位定时器与捕捉外设测量转速,占用较多CPU资源且误差大。通过单片机PIC16F1619和角度定时器(AT),只需较少的CPU资源,就能以准确的激励角度激励火花,且角度分辨率与发动机转速无关。PIC16F1619的外设资源丰富:采用可编程逻辑单元捕捉脉冲发生器的拾波器信号;采用24位信号测量定时器计算转速;采用数学加速器模块计算激励角度的插值;采用互补波形发生器生成调制的脉宽调制(PWM)信号。试验结果表明,使用角度定时器的CDI点火控制方法,较少占用单片机的CPU和RAM资源,控制系统的精度和转速无关,角度分辨率得到大大提高。     

基于PXI总线的单项点火试验测试系统的设计与实现

为了准确测量固体火箭发动机点火装置点火性能的相关参数及P-T曲线,研究并设计了一套基于PXI总线的点火装置单项点火试验测试系统;分析了点火装置点火性能对小型固体火箭发动机的重要性和点火试验测试系统的功能,阐述了点火试验测试系统的设计方案及硬件组成、软件设计和关键技术;对某型号点火装置进行单项点火试验测试,实验结果表明,该系统能够准确测量点火装置的点火性能参数,满足了点火试验测试要求,具有一定的军用价值和推广价值.     

Molex论屏蔽布线系统

为何选择FTP系列 传统上人们选择箔屏蔽布线系统，以利用其固有的改善的电磁兼容性（EMC）和射频干扰（RFI）性能。电磁兼容性（EMC）法规92／31／EEC中规定了与EMI（电磁干扰）辐射及EMI抗干扰能力有关的条款。电磁干扰（EMI）是指对设备或系统的运转有着负面影响的任何无用信号。适合采取屏蔽解决方案的环境包括两类：     

基于Agent组织的多UAV协调模型

无人驾驶飞机(UAV)系统的协调问题是UAV研究领域的一个重要问题。研究了适应于UAV系统的Agent结构模型以及组织模型,提出了一种基于Agent组织的多UAV协调模型并给出了其数学化表述,分析了多UAV协调模型中任务协调、角色协调以及动作协调等三个阶段,并对提出的模型进行了仿真。实验表明,模型具有较好的适应性和稳定性。     

固体火箭发动机电容充电式点火控制系统设计

点火控制系统是某型发动机地面系统的重要组成部分,主要用于完成发动机的常态安全保护和点火控制任务。为优化系统性能,对电容充电原理和充电电路参数计算方法进行了研究,设计了电容充电式点火控制系统,解决了传统发动机点火电路应用大容量电池或电源模块来实现点火控制所带来的设备体积庞大、质量沉重,不便应用于便携式地面系统的问题,不仅可利用电容的瞬间放电能力准确实现对发动机的点火控制,还大大减少了点火电路的质量和体积,有效提高了系统的机动能力,大大扩展了系统的应用范围。     

基于openECU的点火正时控制策略设计

点火系统是发动机的重要主成部分,对发动机的性能有绝对性的影响。在开放式ECU的基础上进行了点火正时策略的设计以及预标定的工作,大大缩短了开发的难度和周期;对某LNG气体机的点火正时策略进行了设计和优化,并结合发动机计算模型（进气,压缩,做功,排气）进行了反馈和验证。使用开放式ECU进行实验开发,可以为实验节省大量的时间和资源,监测不同的输入条件对点火提前角的影响,实现了脉谱的预标定,大大缩短了开发工作,具有一定的实际运用价值。     

基于USB和串口通信的点火能量测试系统设计

为改善某型煤油发动机的冷启动性能,需测定发动机电感式点火系统在不同充磁时间下的点火能量,设计了一套点火能量测试系统,利用VC++开发了点火能量测试软件,实现了测试软件与数字示波器及点火控制器的通信,并进行了点火能量测试。试验结果表明,该测试系统能够准确地测试点火能量。     

磁脉冲式曲轴位置传感器波形分析

曲轴位置传感器是发动机电子控制系统中最主要的传感器之一,它提供点火时刻(点火提前角)、确认曲轴位置的信号,用于检测活塞上止点、曲轴转角及发动机转速。曲轴位置传感器所采用的结构随车型不同而不同,可分为磁脉冲式、光电式和霍尔式三大类。本文针对磁脉冲式曲轴位置传感器分析了其波形检测的方法。     

电磁干扰一扫光

综合布线行业技术的飞速发展,一定程度上归功于千兆位网络发展的巨大推动力。随着应用带宽的不断提高,布线市场中屏蔽与非屏蔽的问题又在老话重提,问题的主要症结在于屏蔽厂商认为随着数据传输速率的不断提高,外界干扰频率将随之增加,只有屏蔽系统才能有效抵御电磁干扰。在对待有电磁干扰的场合是否使用屏蔽或非屏蔽系统,其态度是非常严谨的。那么,什么是电磁干扰,国际上怎么评估呢? 简单地讲,电磁干扰(EMI)就是设备间无用的电磁作用。过大的电磁干扰会降低网络传输的可靠性,使误码率增加从而延长网络传输时间。电磁兼容性(EMC)是要求设备工作于电磁环境中时,不能对其他设备造成不良影响。在布线中既要考虑外界干扰不能过大,也要考虑布线系统不能过分干扰其他系统。国际上对电磁干扰的评估以欧洲89/336/EEC条例(EMC     

Vishay推出新款大电流汽车级电感器

Vishay Intertechnology,Inc.发布新款汽车级的超薄、大电流电感器---IHLE-4040DC-5A,该电感器采用可减少EMI的整体e屏蔽层和紧凑的4040外形尺寸。Vishay Dale IHLE-4040DC-5A能够遏制在镀锡的铜整体屏蔽里与EMI有关的电场,把整体的屏蔽连到地时,在1cm内(电感器的中心位置上面)可以使电场最多减小-20     

基于ARM嵌入式加湿控制器的硬件设计

基于ARM嵌入式加湿控制器硬件设计是为达到用户要求环境湿度而设计的,它通过使用集成的512kBflash、32kB SRAM的LPC2146微控制器MCU、LCM、加湿控制电路来达到环境湿度的调节.加湿控制器读取传感器收集到的环境温度、湿度,通过仅2.2μs转换时间的A/D转换器(集成在LPC2146)转换,MCU快速根据环境下湿度的差异计算出需要加湿控制量,并把温度、环境湿度在LCM中实时用曲线显示出来,同时在不满足用户要求环境湿度时,驱动加湿器进行湿度调节到用户的要求湿度为止.该加湿控制器已经应用到用户对湿度有要求的场合中,性能比较可靠,价格非常便宜,但由于电磁干扰的影响大,需要在抗电磁干扰EMI上进一步加强。     

直喷系统建模及点火正时仿真分析

利用GT-Power软件建立了某无人机二冲程发动机直喷仿真模型,通过实验获取缸压曲线与仿真结果进行对比,验证了仿真模型的正确性。基于验证的直喷系统仿真模型,分析了高低空环境下的点火正时对气缸最高压力、扭矩、燃油消耗率、排气温度和NOX排放量的影响规律。仿真结果可优化无人机直喷系统的点火正时参数,为在高低空环境下提高发动机性能提供理论依据。     

无人机数据链自动测试系统测控组件的设计

针对无人机数据链自动测试系统的研制必要性，文章介绍了该系统测控组件的功能与软、硬件设计，并针对测控组件的强电磁干扰工作环境特点，阐述了硬件及软件的抗干扰措施；应用结果表明，该组件工作稳定可靠，满足自动测试系统的要求。     

Modeling and Sliding Mode Control of a Micro Helicopter-Airplane System

This paper presents the regulation and trajectory tracking for a Micro Coaxial Rocket Helicopter (MCR UAV), as well as the control of a mini aircraft. The former vehicle has the characteristic of performing hover and forward flight while the latter vehicle is considered as an external air transporter for the MCR UAV. For control purposes, the helicopter stabilization is based on sliding mode controllers which avoid the chattering generated during the flight and allow the MCR UAV to perform tracking of smooth trajectories, Furthermore a PD controller stabilizes the aircraft in order to execute semi-autonomous flight. A flight computer for these aerial vehicles consists of a homemade embedded system, low-cost sensors, and signal conditioning circuits, analog filters and actuator. The proposed control algorithms are implemented on the embedded system. Simulation and experimental results show the good performance of the developed system during the flight.     

Spiking neurons and the induction of finite state machines

We discuss in this short survey article some current mathematical models from neurophysiology for the computational units of biological neural systems: neurons and synapses. These models are contrasted with the computational units of common artificial neural network models, which reflect the state of knowledge in neurophysiology 50 years ago. We discuss the problem of carrying out computations in circuits consisting of biologically realistic computational units, focusing on the biologically particularly relevant case of computations on time series. Finite state machines are frequently used in computer science as models for computations on time series. One may argue that these models provide a reasonable common conceptual basis for analyzing computations in computers and biological neural systems, although the emphasis in biological neural systems is shifted more towards asynchronous computation on analog time series. In the second half of this article some new computer experiments and theoretical results are discussed, which address the question whether a biological neural system can, in principle, learn to behave like a given simple finite state machine.     

Dynamic surface active fault tolerant control design for the attitude control systems of UAV with actuator fault

In this paper, an active fault tolerant control (FTC) approach based on transient performance index is proposed for the attitude control systems of unmanned aerial vehicle (UAV) with actuator fault. The nonlinear attitude control system model for UAV with actuator faults is given, which represents the dynamic characteristics of UAV. A fault diagnosis component is used for fault detection and estimation. According to the fault estimation information obtained during the fault diagnosis, the fault tolerant control scheme is developed by adopting the adaptive dynamic surface control technique, which guarantees the asymptotic output tracking and ultimate uniform boundedness of the closed-loop attitude control systems of UAV in actuator faulty case. Further, a prescribed transient performance of the FTC attitude control systems is considered which characterizes the convergence rate and maximum overshoot of the attitude tracking error. Finally, simulation results are shown that the attitude control system states remain bounded and the output tracking errors converge to a neighborhood of zero.     

Consensus controller for multi-UAV navigation

In this paper, we design consensus algorithms for multiple unmanned aerial vehicles (UAV). We mainly focus on the control design in the face of measurement noise and propose a position consensus controller based on the sliding mode control by using the distributed UAV information. Within the framework of Lyapunov theory, it is shown that all signals in the closed-loop multi-UAV systems are stabilized by the proposed algorithm, while consensus errors are uniformly ultimately bounded. Moreover, for each local UAV, we propose a mechanism to define the trustworthiness, based on which the edge weights are tuned to eliminate negative influence from stubborn agents or agents exposed to extremely noisy measurement. Finally, we develop software for a nano UAV platform, based on which we implement our algorithms to address measurement noises in UAV flight tests. The experimental results validate the effectiveness of the proposed algorithms.     

某小型无人机的飞行控制计算机的硬件设计

为了提高无人机的控制性能，针对某小型无人机，提出并实现了以DSP为处理核心的无人机飞行控制计算机的硬件设计方案，详细给出了系统整体方案的设计和具体的硬件选型及接LI设计；介绍了以DSP芯片TMS320LF2407A为主控制器，并在其外围进行了并口方式的A／D、D／A、异步串口通信接口以及存储器的扩展，丰富了系统硬件接口资源，并采用了复杂可编程逻辑控制器（CPLD）实现外围扩展电路的片选、中断控制；该飞行控制计算机具有体积小、自主导航能力强的特点。     

温度传感器在无人飞行器控制系统中的应用

分析了飞行控制器系统采用的2种温度传感器工作原理,探讨了铂电阻传感器非线性校正的硬件和软件实现方法,并设计了相应的测温电路。2种温度传感器均具有体积小、电路结构简单、调试方便、测温范围宽、高可靠性和易使用等优点。试验结果表明:2种温度传感器均能够很好地满足无人飞行器对较低环境温度及时做出反应的要求,提高了无人飞行器执行任务时的可靠性和安全性。     

Effects of System Automation Management Strategies and Multi-mission Operator-to-vehicle Ratio on Operator Performance in UAV Systems

It has been documented that the military intends to increase the number of Unmanned Aerial Vehicles (UAVs) in service while at the same time reducing the number of operators (Dixon et al. 2004). To meet this demand, many of the current UAV operator function will need to be automated. Levels of automation exist along a continuum from fully manual to fully automatic. Different automation strategies have been applied widely in UAV systems. Management by Consent (MBC), where the operator selects the task to be executed, and Management by Exception (MBE), where the computer selects the task to be executed are two proposed levels of automation for future UAV systems. Meanwhile, the optimum operator-to-vehicle ratio for future UAV systems is not yet known. It is expected that the optimum operator-to-vehicle ratio will vary with the level of automation applied to the system. Future UAV systems may require the use of adaptive automation to ensure maximum human–machine performance across varying operator-to-vehicle ratios. This study aims to help determine what levels of automation are most appropriate for different operator-to-vehicle ratios and how adaptive automation should be applied in future UAV systems. We investigated the effect of various operator-to-vehicle ratios and the two automation strategies on UAV mission tasks, results were analyzed using Analysis of Variance (ANOVA) and discussed in the last section of the paper.