Hardware-in-the-Loop Simulation System for Space Manipulator Docking: Model,Stability and Experimental Evaluation

A manipulator-type docking hardware-in-the-loop(HIL)simulation system is proposed in this paper,with further development of the space docking technology and corresponding requirements of the engineering project.First,the structure of the manipulator-type HIL simulation system is explained.The mass and the flexibility of the manipulator has an important influence on the stability of the HIL system,which is the premise of accurately simulating actual space docking.Thus,the docking HIL simulation models of rigid,flexible and flexible-light space manipulators are established.The characteristics of the three HIL systems are studied from three important aspects:the system parameter configuration relation,the system stability condition and the dynamics frequency simulation ability.The key conclusions obtained were that the system satisfies stability or reproduction accuracy.Meanwhile,the influence of different manipulators on the system stability is further analyzed.The accuracy of the calculated results is verified experimentally.

Development of a Low-cost Hardware-in-the-loop Simulation System as a Test Bench for Anti-lock Braking System

Nowadays validation of anti-lock braking systems（ABS） relies mainly on a large amount of road tests.An alternative means with higher efficiency is employing the hardware-in-the-loop simulation（HILS） system to substitute part of road tests for designing,testing,and tuning electronic control units（ECUs） of ABS.Most HILS systems for ABS use expensive digital signal processor hardware and special purpose software,and some fail-safe functions with regard to wheel speeds cannot be evaluated since artificial wheel speed signals are usually provided.In this paper,a low-cost ABS HILS test bench is developed and used for validating the anti-lock braking performance and tuning control parameters of ABS controllers.Another important merit of the proposed test bench is that it can comprehensively evaluate the fail-safe functions with regard to wheel speed signals since real tone rings and sensors are integrated in the bench.A 5-DOF vehicle model with consideration of longitudinal load transfer is used to calculate tire forces,wheel speeds and vehicle speed.Each of the four real-time wheel speed signal generators consists of a servo motor plus a ring gear,which has sufficient dynamic response ability to emulate the rapid changes of the wheel speeds under strict braking conditions of very slippery roads.The simulation of braking tests under different road adhesion coefficients using the HILS test bench is run,and results show that it can evaluate the anti-lock braking performance of ABS and partly the fail-safe functions.This HILS system can also be used in such applications as durability test,benchmarking and comparison between different ECUs.The test bench developed not only has a relatively low cost,but also can be used to validate the wheel speed-related ECU design and all its fail-safe functions,and a rapid testing and proving platform with a high efficiency for research and development of the automotive ABS is therefore provided.

Hardware-in-the-Loop Simulation of Vibration Control of Stay Cables with Damper Based on dSPACE System

A simple and economical method based on dSPACE system is developed to measure the effect of cable vibration control.The experiments,numerical simulation and hardware-in-the-loop(HIL)simulation are carried out for the vibration control of stay cables with dampers.Firstly,the test results of solid cable vibration under harmonic excitation are compared with the numerical simulation results of cable vibration to ensure the correctness of the simulation of cable module.Then,the vibration test results of solid cable with damper under harmonic excitation are compared with the numerical simulation results of solid cable with damper to ensure the correctness of the relevant modules.Finally,the external load and the cable are imported into the real-time simulation system to simulate the control effect of the damper under the current excitation in real time.The results show that the simulation is correct and the HIL simulation is feasible in the bridge engineering.

HIL Simulation of a Mixed Islanded Power Network with External DSP Regulator

The present paper deals with the development of a modular, flexible and structured block to block approach for the study of regulators by implementing the different blocks on a DSP （digital signal processor）. The proposed low-cost approach has been applied and validated by the implementation of an industrial regulator in a real time hardware-in-the-loop simulation of a mixed islanded power network including precise models of the hydraulic system. The studied network is constituted of three different types of electrical power generation systems and a consumer.

无人机飞行控制原型实验设计与实践

针对航空航天类专业课程理论教学与课程实践相结合的需要,对无人机飞行控制系统半实物仿真实验技术进行了研究,设计了无人机半实物仿真实验平台。该实验平台将三轴转台、姿态传感器等作为实物部分,基于Simbox仿真计算机建立无人机飞行控制模型,通过仿真框架软件设计、半实物仿真硬件设备搭建实现无人机姿态控制。该实验平台可应用于无人机飞行控制及科学研究等领域,具有良好的实用价值。

激光制导武器半实物仿真系统的设计与实现

首先,以某激光制导弹药为背景,提出了室内半实物仿真系统的总体设计方案,介绍了一种激光半主动导引头的工作原理。其次,在室内局限环境下,建立了弹目几何关系的数学模型,研究了导引头入瞳光学特性,并根据制导与控制系统的工作原理,设计了末制导段弹道的半实物仿真模型。最后,设置两种末端制导的初始条件,引入导引头和角速率陀螺等弹上部件进行多次弹道仿真试验。试验结果表明,基于该导引头和角速率陀螺的制导与控制系统设计合理,可以实现精确打击。

分布式驱动电动汽车的近似最优转矩矢量控制

针对分布式驱动车辆系统非线性的特性,提出一种基于最优转矩矢量控制的车辆侧向稳定性控制系统。首先使用魔术公式轮胎模型实时估计轮胎力,搭建轮胎侧偏刚度变化的非线性车辆模型。接着借鉴近似线性二次型规划的最优控制思想,设计基于质心侧向加速度的增益可调的横摆转矩控制方法,并根据驱动电机峰值转矩和轮胎摩擦圆的约束条件进行转矩矢量分配。最后进行Car Sim和Lab VIEW联合仿真和硬件在环实验。结果表明,控制系统能对车辆进行有效的实时控制,在显著改善车辆稳定性的同时不严重影响车辆的纵向性能。

基于FPGA的三电平空间矢量脉宽调制算法半实物实验方案

以三电平二极管中性点钳位牵引逆变器电机系统为研究对象,首先对各扇区的几何对称性与矢量作用时间之间的密切关系进行了详细分析。在此基础上,探讨了一种简化三电平空间矢量脉宽调制(SVPWM)算法。然后,给出了该算法基于现场可编程门阵列(FPGA)的详细设计方案,并通过简化乘法器、高效率除法器等关键性设计,避免数字处理器进行大量三角函数运算,减少硬件资源占用,同时兼具FPGA速度快、可移植性好、模块复用率高等特点。最后,通过基于FPGA与dSPACE的半实物实验平台的实验研究,验证了该简化三电平SVPWM算法的正确性及其基于FPGA设计方案的可行性。

航空航天类专业制导控制室内外半实物仿真实验技术研究与应用

针对航空航天类专业制导控制类课程的理论学习与实验教学的需要,进行飞行器制导控制室内外半实物仿真实验教学平台的研发。该平台以“3轴+2轴”转台作为物理实物部分,仿真计算机和制导运动控制模型作为控制核心,通过转台和目标模拟器的运动控制实现高动态目标跟踪控制。结合校企联合和航空航天行业的优势,在外场实验中模拟复杂背景下基于火箭撬平台进行导引头仿真测试,该实验技术符合实际工程应用的需求,同时具有较强创新性、先进性及推广性,能使学生深入理解高动态平台制导控制专业知识,该系统有利于提高学生的创新能力。实践表明,学生在该实验技术的学习过程中,对制导控制实验课程技术有了更深层次的认知、分析和应用,达到了良好的科研教学融合效果。

基于dSPACE的过程控制算法研究

本文介绍了当今流行的半实物仿真技术及过程控制算法,研究了基于MATLAB平台的基于dSPACE仿真平台的半实物仿真原理及基于模糊规则的适应式参数自调整PID控制算法。并将其成功应用于水槽液位过程控制试验系统中。

PEMFC系统过氧比的自适应高阶滑模控制

调节控制质子交换膜燃料电池(PEMFC)空气供给系统过氧比(OER)在理想范围可有效提高PEMFC系统输出净功率.为此,本文首先结合反馈控制理论将非线性PEMFC空气供给系统转化为标准形,并对系统内部动态进行了稳定性分析.然后基于PEMFC空气供给系统系统扩展的状态空间,并提出一种新型的自适应高阶滑模方法.该控制器不需PEMFC空气供给系统模型和干扰/不确定向的界已知的条件,自适应模糊逻辑系统可在线逼近系统中未建模动态.并且通过在线自适应获得的控制增益可保证系统跟踪误差收敛到原点附近的邻域内.最后,结合Lyapunov理论验证了系统的收敛性与稳定性,通过仿真和硬件在环实验进一步验证了该控制器的自适应性与优越性.

Shifting Rule Modification Strategy of Automatic Transmission Based on Driver-vehicle-road Environment

Accidental or frequent shift often occurs when the shifting rule is built based on traditional two parameters （i.e., velocity and throttle）, because the speed of engine varies slower than change of throttle opening. Currently, modifying shift point velocity value or throttle by throttle change rate is one of common methods, but the results are not so satisfactory in some working condition such as uphill. The reason is that these methods merely consider throttle change rate which is not enough for a car driving in driver-vehicle-road environment system. So a novel fuzzy control modification strategy is proposed to avoid or reduce those abnormal shift actions. It can adjust shifting rule by the change rate of throttle, current gear position and road environment information, while different gear position and driving environment get corresponding modification value. In order to compare the results of shifting actions, fuel consumption and braking distance, emergent braking in level road and extra-urban driving cycle（EUDC） working conditions with fuzzy shifting schedule modification strategy are simulated digitally. Furthermore, a hardware-in-the-loop simulation platform is introduced to verify its effect in slope road condition according to the ON/OFF numbers of solenoid valve in hydraulic system. The simulation results show that the problem of unexpected shift in those working conditions may be resolved by fuzzy modification strategy. At last, it is concluded that although there is some slight decline in power performance in uphill situation, this fuzzy modification strategy could correctly identify slope of road, decrease braking distance, improve vehicle comfort and fuel economy effectively and prolong the life of clutch system. So, this fuzzy logic shifting strategy provides important references for vehicle intelligent shifting schedule.

An experimental study of the dual-loop control of electro-hydraulic load simulator (EHLS)

This paper investigates motion coupling disturbance（the so called surplus torque）in the hardware-in-the-loop（HIL）experiments.The＇＇velocity synchronization scheme＇＇was proposed by Jiao for an electro-hydraulic load simulator（EHLS）in 2004.In some situations,however,the scheme is limited in the implementation for certain reasons,as is the case when the actuator＇s valve signal is not available or it is seriously polluted by noise.To solve these problems,a＇＇dual-loop scheme＇＇is developed for EHLS.The dual-loop scheme is a combination of a torque loop and a position synchronization loop.The role of the position synchronization loop is to decouple the motion disturbance caused by the actuator system.To verify the feasibility and effectiveness of the proposed scheme,extensive simulations are performed using AMESim.Then,the performance of the developed method is validated by experiments.

Development of AMT Fault Diagnosis Technique Based on KWP2000

In order to make automatic mechanical transmission （AMT） capable of performing fault self-diagnoses and adaptive to standard communication interface,through technical analysis and intensive study concerning on-board diagnostic protocols now widely applied in Europe and America,KWP2000 on CAN is accepted as a technological path.An AMT fault communication system using hardware-in-the-loop simulation by dSPACE is developed,and communications compatible with ISO 15031-6 is realized on this module.Moreover,a hand-held fault diagnosis instrument with built-in software is designed to facilitate communications with AMT fault communication module with accuracy,rapidity and stableness.Bench and real vehicle experimental results show that the developed instrument and module can perform the anticipated functions,so as to maintain steady communications under the KWP2000-on-CAN protocol.

FPGA-Based Real-Time Simulation of Modular Multilevel Converter HVDC Systems

AC-HVDC-AC energy conversion systems using MMC （modular multilevel converters） are becoming popular to integrate distributed energy systems to the main grid. Such multilevel converters pose a serious problems for HIL （hardware in the loop） simulators required for control, protection design and testing due to the large number of cells that must be simulated individually using very small time steps. This paper demonstrates the advantages of using a very small time step to simulate a MMC topology. The MMC is implemented on FPGA （fiel-programmable gate array） to simulate fast transient with a time step of 250 ns. The AC network and HVDC bus is simulated on the PC, with a slower time step of 10 μs to 20 μs. The simulator architecture and the components simulated on the FPGA and on the PC will be discussed, as well as the method allowing the interconnection of this slow and fast system.

基于虚拟标定技术的混合动力汽车排放研究

基于虚拟标定技术进行混合动力车辆排放仿真研究,首先建立一款高精度的发动机模型及整车模型,利用台架及整车排放测试数据通过空间填充DoE建模及高斯算法,建立排放模型,用硬件在环仿真平台进行实时计算,并将计算结果与试验数据进行对比。研究结果表明,这种基于模型的排放计算方法能够达到精度要求,从而有效缩短标定时间。

FPGA-based hardware-in-the-loop for multi-domain simulation

In this paper,we present a new approach for complex system design,which allows rapid,efficient and low-cost prototyping.This approach can simplify designing tasks and go faster from system modeling to effective hardware implementation.Designing multi-domain systems requires different engineering competences and several tools,our approach gives a unique design environment,based on the use of VHDL-AMS modeling language and FPGA device within the same design tool.This approach is intended to enhance hardware-in-the-loop(HIL)practices with a more realistic simulation which improve the verification process in the system design flow.This paper describes the implementation of a software/hardware platform as a practical support for our approach,the feasibility and the benefits of this approach are demonstrated through a practical case study for power converter control.The obtained results show that the developed method achieves significant speed-up compared with conventional simulation,with a minimum used resources and minimum latency.

Research on the novel discretized ratio control strategies and hardware-in-the-loop test for continuous variable transmission system

Based on traditional continuous control strategy for Continuously Variable Transmission(CVT)ratio,according to the principles of shift control strategy for stepped automatic transmission,the influences of throttle opening and external resistance or vehicle speed on CVT ratio control are analyzed on bumpy road.Under the same variation of external resistance condition,the differences between optimal economic control strategy and optimal dynamic control strategy are discussed.Then,the traditional continuous optimal dynamic and economic control lines are divided into multi-step upshift points.Meanwhile,the corresponding downshift points are set to avoid the interference near shift points.After that,the novel discretized ratio control methods for CVT system are proposed.By respectively discretizing throttle opening and vehicle speed,the discretized ratio control strategy for throttle opening,and the integrated discretized ratio control strategy for throttle opening and vehicle speed are further proposed and simulated.Furthermore,the hardware-in-the-loop(HIL)test system is built to further verify the feasibility and accuracy of discretized ratio control strategies.Both simulation and HIL test results show that the sensitivity of throttle opening and vehicle speed to ratio control is reduced dramatically,the fluctuation of ratio is decreased considerably,the transmission efficiency is increased significantly,and the jerk is declined moderately.