基于VEGA的车辆自动驾驶仿真研究

在研究车辆自动驾驶特性的基础上,采用虚拟现实仿真技术,利用Creator和Vega完成了实体模型的建立和虚拟场景的渲染,完成了仿真系统的开发,完整地演示了从建模、路径导航设置,碰撞检测到最终实现车辆自动模拟驾驶的全过程,并在仿真测试中取得了较好的效果.该系统可以真实的模拟交互式的车辆行驶过程,提供了一个通用的仿真平台,可以大大降低车辆行驶视景仿真建模中的开发成本,并对同类虚拟仿真的研究也具有重要的指导意义.     

电控机械式自动变速器在线故障诊断系统的开发

根据电控机械式自动变速器系统的特点,采用基于模型的设计方法,在MATLAB／SIMUuNK软件环境下,运用Stateflow逻辑系统建模工具建立了AMT系统的在线故障诊断模型,从而有效地对AMT系统中的传感器、执行机构和TCU硬件的主要故障进行在线诊断。大量试验表明,该设计方法是行之有效的且非常实用。     

容错计算机系统的可靠性建模和分布式仿真

对容错计算机系统的可靠性进行评估是一项重要而困难的工作。为容错计算机系统的各个组成部件建立了部件级故障模型,并以此为基础建立了整个容错计算机系统的可靠性测评模型。基于所建立模型,我们提出了分布式仿真的思想,它把系统的各个部件仿真为网络上的一个站点,并增设一台服务器来对整个系统的可靠性性能进行统计和分析。仿真结果验证了建立模型的正确性和方法的有效性。     

履带车辆行驶平顺性仿真及试验

基于虚拟样机技术,结合三维造型软件、有限元分析和多体动力学软件,对履带车辆行驶平顺性仿真技术进行了研究.建立履带车辆的刚柔混合虚拟样机模型及随机不平路面模型,生成平顺性仿真模型系统,通过在F等级随机路面行驶仿真,得到车辆行驶时驾驶员座椅位置振动加速度曲线,根据评价标准对车辆进行平顺性评价,并与实车试验测试数据的计算结果进行对比分析.结果表明,仿真模型系统及评价方法合理,可以为提高和改善履带车辆的机动性能提供有效的方法和手段.     

信号与系统课程实验的软件实施

信号与系统课程实验是该课程的重要内容地是理论联系实际的一个途径。本文基于这一认识,利用工程设计语言Matlab对信号与系统课程的实验进行了计算机仿真,给出了软件实施方案,开发了实验的仿真系统模型。实践表明该实验软件仿真效果良好。     

一种非公路宽体自卸车AMT离合器电控操纵系统的设计

本文通过分析非公路宽体自卸车原有的离合器操纵系统存在的问题,设计了一种AMT离合器电控操纵系统,以STC89C52芯片为核心,采用一些新型的功能模块设计及电控操纵系统使系统自动化,是一种改进现有系统存在问题的新方案,对后期非公路宽体自卸车AMT电控操纵系统的设计有一定的参考意义。     

利用MATLAB/Simulink图形环境和PLECS模块库仿真太阳光电（PV）换流器

本文描述了光电能量转换系统及其控制的仿真。在实时执行之前,为了测试控制算法的有效性,需要进行该系统的仿真研究。另外,为了直接生成dSPACE控制板的实时代码,必须利用MATLAB/Simulink开发控制系统。本文利用MATLAB/Simulink,首次研究了电力系统的仿真。在第二步中,利用PLECS工具箱仿真了电力系统,而且比较了进行实验的仿真模型和所提供的选择性仿真结果。     

基于红外照射仿真的快速搜索相关跟踪干扰点研究

通过人工红外照射改变目标与背景的红外辐射特性能够对相关跟踪形成有效干扰,其中,红外照射的位置对干扰效果具有重要影响。为提升红外照射干扰相关跟踪的效率,文中建立了红外照射仿真搜索相关跟踪干扰点模型,对干扰相关跟踪的有效照射位置进行快速搜索。首先,运用TracePro光线追迹软件建立了真实实验条件下的红外照射系统模型,并利用高斯模型对照射光斑的照度分布进行了拟合。然后,在一定空间范围内,采用二维扫描的方式进行真实照射干扰和仿真照射干扰对比实验,结果表明:仿真照射与真实照射的干扰结果一致性达到了98%,且仿真照射找出了真实照射条件下干扰相关跟踪的全部干扰点,从而很好地验证了文中方法的有效性。     

基于Vega的视景仿真应用系统研究与实现

以开发一套地下洞室视景仿真应用系统为目的,研究了视景仿真应用系统开发中纹理映射、碰撞检测、视点快速切换、模型动态调度技术、对象拾取等关键技术,提出了可行的解决方案。基于Creator构建了地下洞室和洞室地表三维模型数据库,利用Vega建立虚拟场景并进行仿真驱动,应用Vega API编程技术在VC .NET集成开发环境中完成了地下洞室视景仿真应用系统的设计和实现。     

基于Simulink的数字AGC系统设计与仿真

在Simulink环境下搭建了数字自动增益控制（AGC）系统的仿真平台,该平台由中频信号模型、可控增益放大器、A/D采样与I、Q分离模型及峰值提取和AGC控制算法部分组成,各个部件与真实器件、模块相对应,且参数可变。该平台按照真实AGC系统的信号流程进行仿真,能够为数字AGC算法的性能进行预测和评估,为AGC系统的参数选择提供了分析工具。     

A satellite-tracking K- and Ka-band mobile vehicleantenna system

This paper describes the development of the K- and K_a-band, satellite-tracking mobile-vehicular antenna system for NASA's ACTS Mobile Terminal (AMT) project. ACTS is NASA's Advanced Communications Technology Satellite, which will be launched into its geostationary orbit in September 1993. The AMT task will make the first experimental use of the satellite soon after the satellite is operational, to demonstrate mobile communications via the satellite from a van on the road. The AMT antenna system consists of a mechanically steered small reflector antenna that uses a shared aperture for both frequency bands and fits under a radome of 23 cm diameter and 10 cm height, and an antenna controller that tracks the satellite as the vehicle moves about. The RF and mechanical characteristics of the antenna and the antenna tracking control system are discussed. Laboratory measurements of the antenna performance are presented     

An efficient adaptive intelligent routing system for multi‐intersections

With the rapid development of wireless technologies and the growing emphasis on vehicle safety, many vehicular ad hoc network applications have been extensively used. This study attempts to use vehicular ad hoc network technologies for autonomous driving to improve and reduce traffic congestion and vehicle waiting time. Therefore, this study proposes an adaptively intelligent routing system, which uses V2V communications to increase vehicle speed, allows vehicles to communicate with traffic control systems, arranges appropriate vehicle routes based on queuing theory, and uses traffic signals for information exchange. The timing of traffic signals is decided according to road traffic density. To decrease vehicle waiting time at intersections, every vehicle's speed is adjusted based on the distance between the vehicle and the traffic signals. In the simulation, automated vehicles and a more realistic car‐following model are taken into consideration and vehicle speeds are regulated based on speed limits and safe following distance on most roads. The simulation result reveals that our proposed adaptively intelligent routing system outperforms periodic system in average vehicle speed and average waiting time at both single and double cross intersections. Copyright © 2016 John Wiley & Sons, Ltd.     

一类基于自适应反馈控制的车辆编队研究

文中研究了基于生物刺激神经动力学方法的车辆编队控制问题。以编队车辆的运动学模型为基础,在跟随领航者体系下建立车辆编队系统动态模型。根据李雅普诺夫稳定性理论,设计出新的自适应反馈跟踪控制器,将车辆跟随问题转化为系统误差的控制问题,并运用仿真实验验证控制器的有效性。与现有的反馈跟踪控制器进行对比后可以看到,文中所设计的控制器在稳定性和收敛速度上有了进一步的提高。     

Development of electro-hydraulic proportion control system of track-laying machinery for high speed railway construction

This paper mainly deals with the development of electro-hydraulic(EH) proportion control system for travelling and track-laying work in the track-laying machinery (TLM) for high speed railway construction. Different from TLM used to low speed railway construction, TLM for high speed railway construction is a kind of the full-automatic continuous track-laying work machinery, and it is characterized by flowchart process and self-travelling. In order to increase the operation production rate and work quality of the track-laying machinery, a distributed electro-hydraulic proportional control system to be based on controller area network(CAN) bus type of networked control network which can realize the coordinated control among multiple hydraulic implement mechanisms is proposed. In this system, the travelling speed of the TLM is chosen as the primary connected variable of sleeper-working. Using the measured travelling speed of TLM via the triggering-wheel, the developed system can implement the control for the wheel-rail travelling speed and tractive force, the sleeper-laying and sleeper-conveying is constructed. Addressed the coordinated control of the travelling system, a compound cooperated control system is designed for coordinating between the tractive forces and the travelling speeds of the crawler vehicle and the wheel-track work vehicle. For the speeds coordination of multiple-sleeper-conveying-motor, the relative coupling control law is presented based on the threshold type of fuzzy PID. The simulation, the worksite test and the practical application show that the developed control system can meet the requirements of the sleeper-laying operation.     

Modeling, Analysis, and Neural Network Control of an EV Electrical Differential

This paper presents system modeling, analysis, and simulation of an electric vehicle (EV) with two independent rear wheel drives. The traction control system is designed to guarantee the EV dynamics and stability when there are no differential gears. Using two in-wheel electric motors makes it possible to have torque and speed control in each wheel. This control level improves EV stability and safety. The proposed traction control system uses the vehicle speed, which is different from wheel speed characterized by a slip in the driving mode, as an input. In this case, a generalized neural network algorithm is proposed to estimate the vehicle speed. The analysis and simulations lead to the conclusion that the proposed system is feasible. Simulation results on a test vehicle propelled by two 37-kW induction motors showed that the proposed control approach operates satisfactorily.     

纯电动中型客车动力系统参数匹配及性能研究

针对现有车辆改装技术缺乏相应的参数匹配研究及动力学仿真分析,提出利用参数匹配和动力学分析研究汽车改制的方法,该方法以“LS6600C1”型普通中型客车改装的纯电动试验车为研究对象,对动力系统进行参数匹配设计,并利用电动汽车仿真软件ADVISOR建立相应的纯电动汽车动力系统及整车仿真模型,对整车模型的最高车速、加速能力、爬坡性能和续驶里程等指标进行了仿真研究。结果表明,典型工况下改装后的纯电动试验车续驶里程、最高车速、加速性能和爬坡性能等均满足普通中型客车的运行要求和使用条件,该改装技术具有广泛的应用前景。     

基于数据采集卡的直流调速系统实验

数字控制调速系统因其控制器开发周期短并具有开放性的特点,越来越多的应用到本科实验教学中。作者开发了基于数据采集卡的直流调速系统实验,无需对传统模拟实验设备改造,利用数据采集卡NI USB-6008将转速和电流信号传输给上位机,上位机输出移相控制电压控制电机驱动电路,实现上位机与实际硬件系统的数据通信及控制。控制程序在MATLAB/Simulink环境下编写,形成可视化控制界面,方便修改程序和控制器参数。本文阐述了实验系统的整体方案设计,给出了完整的控制程序框图。通过实验结果验证了该实验系统控制策略的有效性和可行性。     

A new strategy for traction control in turning via engine modeling

The driving stability is affected by driven wheel slip, which can be controlled by the driven wheel torque. In a vehicle powered by an internal combustion engine, the torque can be controlled by an engine management system. The sliding mode algorithm is the mechanism behind the design of the traction control system (TCS). The longitudinal slip is controlled by the position of the throttle valve. The vehicle model used has seven degrees of freedom and a two-state engine model, i.e., the mass of air in the intake manifold and the engine speed. Time-delay transport is considered in the engine model used. A nonlinear tire model for combined slip is used for tire force computation. Due to the nonlinear dynamic of the tire, vehicle, and engine, the control method of sliding mode is used for its robustness. A controller is designed based on the dynamic surface control, for which two first-order surfaces are defined. The effectiveness of the controller is demonstrated with simulation results for different maneuvers. Results show that for different road conditions, the acceleration performance, directional stability, and steerability of a vehicle equipped with TCS is improved. The reason is that the slip is controlled by keeping it in a desired range     

高超声速飞行器递阶滑模控制研究

针对高超声速飞行器轨迹高度和速度跟踪控制问题,基于纵向动力学的输入/输出线性化模型,设计了递阶滑模控制器和非线性扰动观测器,用于解决系统存在不确定性问题和执行机构带有死区非线性问题,对于所设计的控制器和观测器进行了稳定性分析,并且通过仿真验证了本文提出的方法能够提高系统的收敛速度和收敛精度并能克服执行机构死区的影响。     

Computer simulation and analysis of a new polyphase multipole motordrive

A new configuration for a high-power-density, high-efficiency polyphase multipole permanent magnet motor and its control system are presented. The mathematical model and simulation for this motor drive are presented in detail. The motor is essentially a kind of brushless DC motor with a novel arrangement of its magnet and winding. The control system is virtually a dual closed-loop system with a current controller as the inner loop and a speed controller as the outer loop. State-space equations are used for the mathematical model of the motor, and real-time simulation is applied for the controller and switching devices. The simulation results are verified with the experimental results and shown to be very satisfactory