On modeling approach for embedded real-time software simulation testing

Modeling technology has been introduced into software testing field. However, how to carry through the testing modeling effectively is still a difficulty. Based on combination of simulation modeling technology and embedded real-time software testing method, the process of simulation testing modeling is studied first. And then, the supporting environment of simulation testing modeling is put forward. Furthermore, an approach of embedded real-time software simulation testing modeling including modeling of cross-linked equipments of system under testing （SUT）, test case, testing scheduling, and testing system service is brought forward. Finally, the formalized description and execution system of testing models are given, with which we can realize real-time, closed loop, mad automated system testing for embedded real-time software.

Simulation of large-scale numerical substructure in real-time dynamic hybrid testing

A solution scheme is proposed in this paper for an existing RTDHT system to simulate large-scale finite element （FE） numerical substructures. The analysis of the FE numerical substructure is split into response analysis and signal generation tasks, and executed in two different target computers in real-time. One target computer implements the response analysis task, wherein a large time-step is used to solve the FE substructure, and another target computer implements the signal generation task, wherein an interpolation program is used to generate control signals in a small time-step to meet the input demand of the controller. By using this strategy, the scale of the FE numerical substructure simulation may be increased significantly. The proposed scheme is initially verified by two FE numerical substructure models with 98 and 1240 degrees of freedom （DOFs）. Thereafter, RTDHTs of a single frame-foundation structure are implemented where the foundation, considered as the numerical substructure, is simulated by the FE model with 1240 DOFs. Good agreements between the results of the RTDHT and those from the FE analysis in ABAQUS are obtained.

Real-time hybrid simulation of structures equipped with viscoelastic-plastic dampers using a user-programmable computational platform

A user-programmable computational/control platform was developed at the University of Toronto that offers real-time hybrid simulation （RTHS） capabilities. The platform was verified previously using several linear physical substructures. The study presented in this paper is focused on further validating the RTHS platform using a nonlinear viscoelastic-plastic damper that has displacement, frequency and temperature-dependent properties. The validation study includes damper component characterization tests, as well as RTHS of a series of single-degree-of-freedom （SDOF） systems equipped with viscoelastic-plastic dampers that represent different structural designs. From the component characterization tests, it was found that for a wide range of excitation frequencies and friction slip loads, the tracking errors are comparable to the errors in RTHS of linear spring systems. The hybrid SDOF results are compared to an independently validated thermal- mechanical viscoelastic model to further validate the ability for the platform to test nonlinear systems. After the validation, as an application study, nonlinear SDOF hybrid tests were used to develop performance spectra to predict the response of structures equipped with damping systems that are more challenging to model analytically. The use of the experimental performance spectra is illustrated by comparing the predicted response to the hybrid test response of 2DOF systems equipped with viscoelastic-plastic dampers.

Real-Time Hybrid Simulation of Seismically Isolated Structures with Full-Scale Bearings and Large Computational Models

Hybrid simulation can be a cost effective approach for dynamic testing of structural components at full scale while capturing the system level response through interactions with a numerical model.The dynamic response of a seismically isolated structure depends on the combined characteristics of the ground motion,bearings,and superstructure.Therefore,dynamic full-scale system level tests of isolated structures under realistic dynamic loading conditions are desirable towards a holistic validation of this earthquake protection strategy.Moreover,bearing properties and their ultimate behavior have been shown to be highly dependent on rate-of-loading and scale size effects,especially under extreme loading conditions.Few laboratory facilities can test full-scale seismic isolation bearings under prescribed displacement and/or loading protocols.The adaptation of a full-scale bearing test machine for the implementation of real-time hybrid simulation is presented here with a focus on the challenges encountered in attaining reliable simulation results for large scale dynamic tests.These advanced real-time hybrid simulations of large and complex hybrid models with several thousands of degrees of freedom are some of the first to use high performance parallel computing to rapidly execute the numerical analyses.Challenges in the experimental setup included measured forces contaminated by delay and other systematic control errors in applying desired displacements.Friction and inertial forces generated by the large-scale loading apparatus can affect the accuracy of measured force feedbacks.Reliable results from real-time hybrid simulation requires implementation of compensation algorithms and correction of these various sources of errors.Overall,this research program confirms that real-time hybrid simulation is a viable testing method to experimentally assess the behavior of full-scale isolators while capturing interactions with the numerical models of the superstructure to evaluate system level and in-structure response.

Seismic performance evaluation of VCFPB isolated storage tank using real-time hybrid simulation

Variable curvature friction pendulum bearings(VCFPB)effectively reduce the dynamic response of storage tanks induced by earthquakes.Shaking table testing is used to assess the seismic performance of VCFPB isolated storage tanks.However,the vertical pressure and friction coefficient of the scaled VCFPB in the shaking table tests cannot match the equivalent values of these parameters in the prototype.To avoid this drawback,a real-time hybrid simulation(RTHS)test was developed.Using RTHS testing,a 1/8 scaled tank isolated by VCFPB was tested.The experimental results showed that the displacement dynamic magnification factor of VCFPB,peak reduction factors of the acceleration,shear force,and overturning moment at bottom of the tank,were negative exponential functions of the ratio of peak ground acceleration(PGA)and friction coefficient.The peak reduction factors of displacement,acceleration,force and overturning moment,which were obtained from the experimental results,are compared with those calculated by the Housner model.It can be concluded that the Housner model is applicable in estimation of the acceleration,shear force,and overturning moment of liquid storage tank,but not for the sliding displacement of VCFPBs.

A Portable Multi-functional Real-time Digital Simulator Dedicated to Protective Relay Testing

The paper intfoduces a PC-DSP based real-time digital simulator which is portable in size and aimed at the closed-loop testing of various types of protective relays for their design and application. The simulator can be widely used in not only concerning utilities but also manufacturers and research / certification institutes because of its many functions. The hardware architecture and software implementation of the simulator are described. The main features and functions of the simulator are also

Numerical Simulation of Float-Over Installation for Offshore Platform

In this paper,a numerical investigation of a float-over installation for an offshore platform is presented to verify the feasibility of the actual installation.The hydrodynamic performance of a T-barge is investigated in the frequency domain,and the coupled motions are analyzed in the time domain.We then compare with those of the model test and determine that the response amplitude operator and the time series agree quite well.The barge exhibits favorable hydrodynamic behavior in the considered sea state,and the equipment loads are allowable.Themooring systemand sway fender forces are within the permissible range.Based on these results,we can verify that the actual installation of the offshore platform is feasible.We accurately simulated many important factors and effectively reduced the risk associated with the offshore installation,which is of great importance.As such,we demonstrate that the numerical simulation of the float-over installation for offshore platforms has practical engineering significance.

Environmental simulation platform and its application to geodesic instruments for a performance study

In this study,an environmental simulation platform(ETS-02)was constructed for high-precision geodesic instruments(e.g.,absolute/relative gravimeters and inclinometers),to test the disturbances caused by environmental fl uctuations.The outer layer of the platform was constructed with two sets of rectangular electromagnetic coils,which generated the required magnetic fi eld when current was applied.The inner layer was a closed cabin in which radiators were distributed such that the temperature of the experimental space inside the cabin could be controlled,by energy exchange between the radiators and a thermal controller through the fl owing liquid.A high-precision hexapod was used to simulate the tilt-related eff ect.The platform was capable of adjusting temperatures within a dynamic range of 0℃-70℃ at a resolution of 0.01℃.The noise of the power-spectrum density when the cabin was set to room temperature was measured as 0.03℃/Hz^(1/2) at 1 mHz.The magnetic field simulation had a dynamic range of±300μT and stability of 20 nT.The resolution of the ground-tilt simulation was 1 arc s.The inner space of the platform had a volume of approximately 5 m^(3),which is sufficient for most types of instruments to be tested for a general environmental coupling effect.To illustrate the application of the platform,a dual-axis inclinometer was built and tested carefully with the platform,and the accuracy of the calibration factors was found to be signifi cantly improved.

CBTC Simulation Platform Design and Study

In order to train and test the functionality of the CBTC signal system, this paper designs simulation platform’s architecture and function module based on the CBTC principle firstly. Then, it detailedly discusses the main content and key algorithms about train module and trackside module. Finally, it builds CBTC simulation test platform, used for training of rail transit signal related specialized student and detecting the main function of actual CBTC system based on Shanghai Metro Line 9.

Study on the Effect of Multi-Type Current Transformers Hybrid Operation on Differential Protection of the Bus Based on Dynamic Simulation

This paper analyzes characteristics of multi type current transformers hybrid operation for each branch of the bus and their effects on differential protection of the bus. By theoretically analyzing transmission characteristics of multi type current transformers and their influence factors, we study the dynamic model testing method of multi type current transformers for the bus, and design 3 kinds of testing schemes by making the equivalent model based on the field of P-level current transformer, TPY-level current transformer and electronic current transformer, and build the hybrid operation testing platform of multi type current transformers. Finally, we compare and analyze the transmission characteristics difference of multi type current transformers on the same branch and the characteristics difference of hybrid operation in two successive external faults, analyze the cause behind the differences, and put forward the corresponding improvement measures.

Matlab/Simulink代码生成技术在RTDS上的应用

针对实际电力系统运行和控制的复杂性与Matlab仿真非实时性的矛盾,提出跨平台联合仿真。采用基于Matlab/Simulink代码生成技术与RTDS实时仿真系统相结合的方法,以高压直流输电系统模型为研究对象,利用Embedded Coder开发工具对系统的控制模块进行代码生成,并在RTDS中完成代码移植实验。通过对比仿真波形,验证得到结果行为一致。由此表明,该方法能够有效利用Simulink良好的开发环境和RTDS的实时仿真特性,在离线仿真成功的基础上,完成实时仿真测试,使工作便捷高效,同时保证结果精准可信。

Design and Validation of a Hardware-In-The-Loop Based Automated Driving Simulation Test Platform

With the iterative development of autonomous driving technology,selfdriving cars will be one of the most competitive areas in the future.In order to provide students with a better understanding and more comprehensive grasp of autonomous driving technology,a hardware-in-the-loop based autonomous driving simulation test platform has been built.The hardware-in-the-loop system integrates MATLAB/Simulink to build the core control algorithm model,CarMaker simulation software to provide a virtual display interface and vehicle dynamics model,and NVIDIA Jetson to deploy the ECU(Electronic Control Unit)to improve the algorithm power and Logitech G29 series driving simulators providing signal input.It provides a simulation test platform for the development and testing of advanced driver assistance systems,the development and testing of upper layer control algorithms and underlying actuators for autonomous driving,and can provide a teaching and experimental platform for undergraduate students and a development foundation for postgraduate practice.

基于MATLAB／SIMULINK的火控系统动态仿真试验平台设计

火控系统动态仿真试验平台是基于ＭＡＴＬＡＢ／ＳＩＭＵＬＩＮＫ研制的仿真工具。着重介绍了它的功用和软件的树型结构，并以某型雷达方位角天控系统为例，介绍了应用试验平台进行动态仿真和性能分析时的基本步骤。

地震作用下非等宽平台路堑边坡的动力响应研究

非等宽平台设计是提高碎裂岩体路堑高边坡动力稳定性的有效方法之一,在规范平台宽度不小于2 m背景下,研究该类型边坡的动力响应特征具有重要工程应用价值。通过FLAC3D有限元软件计算三级台阶式边坡平台位置的PGA放大系数、塑性变形区和最大剪应变,然后基于数值模拟结果设计大型振动台物理模拟试验开展非等宽台阶式边坡变形失稳特征和PGA放大系数变化研究,对二级平台宽度引起的边坡破坏程度进行分析,提出路堑边坡工程设计建议。数值模拟表明,随着中间平台宽度增加PGA放大系数先减后增,考虑平台的分割效应下建议该工程二级平台宽度为4 m;物理试验表明,边坡易在平台处产生应力集中,平台分割效应使边坡逐渐分解为局部破坏,地震作用下发生累进变形破坏,分为缓慢变形、加速变形和失稳破坏阶段。研究成果为该类型路堑边坡平台的设计提供了依据。

高级驾驶辅助系统一体化仿真测试平台开发设计

基于法规标准搭建一体化仿真测试平台智能驾驶测试场景,以及对实际道路测试研究成果和用户测试需求,搭建实际道路对标测试用例库。通过该平台可以根据测试结果评价被测硬件,并可以修改一体化仿真测试平台处理器中的一体化仿真测试平台算法和软件后,就可以快速进行ADAS系统的开发、测试、验证和演示,既减轻实车ADAS测试的成本,又能保证ADAS测试的人员安全性,大大提高ADAS测试的工作效率。

数字专网的通信终端与加密组件测试系统设计

为提高数字专网的通信终端与配套加密组件测试效率,降低实装测试环境的构建、运维及人力成本,开展了基于半实物仿真的测试系统设计;对通信终端与加密组件的测试需求进行了分析,提出并实现了一种模拟数字专网的通信建链流程和加密通信业务流程的方法;采用了通用AXIe(仪器与测试高级电信计算架构的扩展)测试平台与扩展测试仪器的架构进行系统设计,实现与不同测试对象的物理接口适配、信号调理以及报文数据交互控制,为通信终端及加密组件的加密业务成功率测试、语音质量评测以及远供工作电流测量提供自动化测试技术手段;经验证,测试系统通信链路时延<100 ns,可为通信终端提供良好的语音质量评测环境,PESQ(感知语音质量评测模型)测试≥4.20,可支持加密业务成功率指标≥99.9%的无人值守测试。

列控系统仿真测试关键技术

随着我国高铁线路网络化规模持续扩大及列控系统运用需求日趋复杂,仿真测试手段作为高铁现场测试的有效补充和完善,已成为列控系统测试技术发展的必然趋势。开展适用于工程化的列控系统仿真测试技术研究,构建基于云平台的总体架构;重点研究平台快速搭建与切换、虚实结合与虚实互换、测试案例编制与序列自动生成等关键测试技术,从而实现仿真平台自动测试功能,并结合实际线路进行广泛验证。应用效果表明,仿真测试平台能有效提高测试的覆盖度和测试深度,并在现场试验前提前发现问题,满足工程化应用需求。列控系统仿真测试平台的成功研制,为现场联调联试提供了重要补充。

无人船避障导航算法仿真测试平台设计与开发

为解决无人船避障导航算法验证成本高的问题,在实验室中为相关算法提供便捷高效的离线测试方案,利用虚拟现实技术,基于Unity 3D开发平台,采用插件动态加载方法,设计开发了一款仿真测试软件平台。在此软件平台中能够实时生成具有随机障碍物的虚拟近岸海洋环境,将自主设计开发的避障导航算法嵌入无人船运动过程中,对相关算法的性能指标进行测试和记录展示。设计开发的无人船避障导航算法仿真测试平台,为无人船关键测控算法的离线仿真测试验证提供了新的手段,实验过程易于复现,算法效果比对直观。与实船实验相比节省了大量的人力物力,提高了算法测试验证的便捷性和效率。

新型列控系统无线闭塞中心测试平台研究

新型列控系统是对我国列车运行控制系统的最新研究与技术探索,无线闭塞中心作为新型列控系统的地面核心设备,实时控制列车间的追踪间隔,保障管辖范围内列车安全运行。为发掘新型列控系统无线闭塞中心设计中的不足,需利用测试平台对其安全功能进行充分验证。既有无线闭塞中心测试平台由于逻辑及数据结构设计问题,难以适配新型列控系统的工程数据,且无法满足新型列控系统部分功能的测试需求。通过分析新型列控系统工程数据及无线闭塞中心系统功能,对既有测试平台进行升级,将逻辑构建方式由以数据为基础调整为以模型为基础,降低测试平台与工程数据的耦合性;利用真实线路数据及新型列控系统中典型运用场景对该测试平台功能进行验证。验证结果表明,该测试平台解决了适配度不高、数据配置复杂的问题,可以满足新型列控系统无线闭塞中心多场景测试需求。

面向果园车辆自主导航算法的仿真测试平台设计

为测试和评价果园车辆自主导航算法的性能,采用数学分析软件MATLAB搭建面向果园车辆自主导航算法的仿真测试平台。仿真测试平台通过构建果园种植模型、激光雷达(Light detection and ranging,LiDAR)测量模型、车辆运动学模型、车辆动力学模型和电机控制模型实现虚拟果园测量和车辆运动过程模拟,通过可视化测量数据、导航过程和导航偏差显示导航结果并评价导航算法性能。对单一模型和平台整体的性能测试结果表明,仿真测试平台可靠,针对基于2D LiDAR的导航路径生成和跟踪算法,仿真测试平台能够有效测试和评价不同果园种植参数及车辆初始状态下的算法性能,满足果园车辆自主导航算法的测试需求。