Heuristic resource allocation and scheduling method for distributed automotive control systems

This paper presents a heuristic resource allocation and scheduling method, which is based on an integrated architecture that enables multiple missions to be embedded in a single electronic control unit (ECU) and a single mission to be distributed over multiple ECUs. The proposed design method is composed of resource(e.g. task and message) allocation, scheduling, and attribute assignments. From a given target application’s task graph, the method generates a scheduling table specifying the release, start, and completion timings of tasks and messages. After that, all relevant attributes(e.g. priority of tasks and messages) are automatically assigned. In order to guarantee the functional and temporal requirements of target applications, design constraints such as the worst case response time, deadline, precedence relations, and physical limitations are concurrently considered. A chassis control system consisting of electronic stability control, an electro-mechanical brake, continuous damping control, and electronic air suspension is employed for evaluating the proposed method. The conventional chassis control system which is composed of seven ECUs was redesigned by only four ECUs without the degradation of control performance. Consequently, it is expected that the development time and production cost of distributed automotive control systems can be significantly reduced by the proposed design method.     

Approximate optimal AUTOSAR software components deploying approach for automotive E/E system

The AUTOSAR has been developed as the worldwide standard for automotive E/E software systems, making the electronic components of different suppliers to be employed universally. However, as the number of component-based applications in modern automotive embedded systems grows rapidly and the hardware topology becomes increasingly complex, deploying such large number of components in automotive distributed system in manual way is over-dependent on experience of engineers which in turn is time consuming. Furthermore, the resource limitation and scheduling analysis make the problems more complex for developers to find out an approximate optimal deploying approach in system integration. In this paper, we propose a novel method to deploy the AUTOSAR components onto ECUs with the following features. First, a clustering algorithm is designed for deploying components automatically within relatively low time complexity. Second, a fitness function is designed to balance the ECUs load. The goal of our approach is to minimize the communication cost over all the runnable entities while meeting all corresponding timing constraints and balancing all the ECUs load. The experiment results show that our approach is efficient and has well performance by comparing with other existing methods in specific and synthetic data set.     

Requirement-based testing of an automotive ECU considering the behavior of the vehicle

HILS (Hardware In the Loop Simulation) and RBT (Requirement-Based Testing) are widely used to evaluate the performance and reliability of automotive ECUs (Electronic Control Units). The HILS method is used to predict the behavior of ECU-installed vehicles and to evaluate the performance of ECU controllers. RBT evaluates whether the embedded system satisfies the pre-defined requirements. In this study, the behavior of a vehicle is regarded as a system requirement, and an embedded system test procedure that evaluates the system requirement is proposed. In particular, a new method is introduced, which integrates HILS with RBT. Using the proposed method, the behavior of an articulated vehicle equipped with an AWS (All Wheel Steering) ECU is evaluated with RBT software.     

基于实时操作系统车载 ECU 双分区软件空中下载升级技术

针对空中下载（Over The Air，OTA） 升级失败时，实时操作系统 （Real Time Operating System，RTOS） 控制器无法进行软件回滚的问题，提出了一种双分区升级技术，此技术分为同面启动升级和异面启动升级。同面启动升级通过外扩存储器作为备份分区，升级时将原程序复制至备份分区后将软件下载至激活分区启动执行；而异面启动升级通过读取控制器分区信息将软件下载至备份分区，利用地址重映射技术和SWAP AB技术进行分区切换，从而实现升级或失败时软件回滚。通过搭建测试环境验证了该软件回滚技术的可行性、有效性及稳定性。     

一种适用不同通信方式基于XCP协议的ECU标定工具的开发

针对汽车ECU的多样性,设计了基于XCP协议的集成多种通信方式的标定平台.开发了主、从节点的XCP驱动程序.在相同的协议层下,构建了基于CAN总线和串口的两种传输层结构,使标定系统同时适用于两种不同的通信方式,并对系统的实时性进行了测试和分析.具体的应用实例说明了该系统使用方便,工作灵活,为车载ECU的高效开发提供了有效工具.     

基于CCP协议汽车电控单元标定系统的设计

介绍了CCP协议的基本原理、通信方式以及用于ECU标定的各种工作模式,讨论了一种基于该协议的汽车电控单元标定系统的设计方法。实际应用结果表明,该标定系统可以有效地实现对多个汽车电控单元进行在线标定,并可以针对不同用户需求提供不同的定制功能,在汽车电子控制系统开发中将能得到较好的应用。     

柴油机电控技术综合研究

对柴油机电控技术进行了比较全面的探讨，重点讨论了柴油机电控技术的研究思路和模块化开发各类电控单元的软硬件技术，提出了基于CAN总线的多电控单元同时优化的电控柴油机集成开发环境建设，为全面优化和监控柴油机的综合性能奠定了基础。最后给出了这些技术在电控VE泵开发和高压共轨电控喷油系统中的应用实例及结果。     

ECU输出接口功率驱动器件故障检修方法

介绍了ECU输出接口功率驱动电路的特点和工作原理。指出ECU输出接口故障一般是由于功率驱动器件损坏引起的。提出了通过ECU输出接口控制端找到相应功率驱动器件的方法；介绍了判断该常用功率驱动器件是否损坏的方法、代换原则以及对特殊封装的功率器件的识别和代换；给出了功率驱动器件更换后的试验方法。如果ECU故障是由输出接口故障引起的，则可以采用所介绍的方法维修而不必更换整个ECU，从而有效降低维修成本。     

Approach to functional safety-compliant ECU design for electro-mechanical brake systems

In this paper, we propose a design approach to a functional safety-compliant ECU for an electro-mechanical brake (EMB) control system or an electronic wedge brake (EWB) control system. Brake actuators in a brake-by-wire (BBW) system such as EMB or EWB are characterized by the safety-critical functions which are now executed by using many electric and electronic devices with application software. Based on hazard analysis and risk assessments of the automotive functional safety standard ISO 26262, the proposed EMB control system should be ASIL-D-compliant, which is the highest ASIL level. To this end, a hardware and a software design method is introduced to implement functionl safety-oriented monitoring functions which are based on an asymmetric dual-core architecture with an external watchdog processor. It is shown by using EMB hardware-In-the-Loop-Simulation (HILS) that the proposed ECU design approach is very effective when a hardware fault or software execution faults occur in the EMB ECU, moreover, this functional safety-compliant design can be well combiled with the sensor fault-tolerant control logic.     

Reducing the memory footprint of OSEK-based systems via stack sharing and light-weight ready queues

OSEK OS (Offene Systeme und deren Schnittstellen für die Elektronik in Kraftfahrzeugen Operating System) is an open, real-time operating system standard for ECU software in vehicles. Because it was originally designed to be used in an extremely resource-constrained environment, an OSEK-compliant operating system must incur low processing overhead and memory usage. Unfortunately, as OSEK OS has evolved over time, it now specifies nontrivial kernel features along with multiple conformance classes and application modes. This may lead to unwanted dynamic resource usage in a system using OSEK OS unless the standard is carefully interpreted and designed into an OSEK OS implementation. In this paper, we analyzed the various kernel features of OSEK OS and their interactions to identify areas in the standard that warrant further resource usage optimization. In particular, we attempted to reduce the run-time memory footprint. Based on our analyses, we present two kernel mechanisms: (1) stack sharing among tasks and (2) light-weight ready queue handling specialized for OSEK OS conformance classes. We also offer implementation methods for the proposed mechanisms by extending OIL and associated tools. Finally, we show the effectiveness of the proposed mechanisms via extensive experiments. Our mechanisms allow OSEK-based systems to use only 36% of the memory requirements of conventional OSEK-based systems on average.     

混合动力系统的台架试验研究

针对所开发的混合动力系统的特点,建立了包括测功机、发动机及ECU、电动机及电机控制器ECU、液晶仪表、电池及管理系统ECU、软件监控界面等在内的动力系统测试平台。通过台架试验,实现了发动机和电动机双驱动动力源的参数匹配,节约了开发成本,缩短了开发周期,完成了用车辆难以进行的试验,验证了整车的控制逻辑及其相关的控制策略,为转鼓试验和整车的进一步开发研究奠定了基础。     

天然气发动机电控单元原型的研制

为将NQ120柴油机改装成天然气单燃料发动机,对其喷射及点火系统进行深入研究。设计了具有点火及喷射功能的电控系统原型,包括系统硬件和软件;基于Labview的串行通信模块开发了一款在线标定监控软件。台架试验结果显示,该电控系统原型可精确控制点火时刻和燃料喷射量,完善后具有很好的应用价值。     

实时多任务系统下的CAN通信模块的设计

介绍了高压共轨柴油机控制器的CAN接口硬件电路的设计;着重进行了实时多任务系统下的CAN通信模块的软件结构设计方法的研究。研究结果表明,所设计的CAN接口硬件电路能够满足实际发动机控制系统的应用需要;所构建的CAN通信软件模块,在满足CAN通信实时性要求的同时,降低了CAN通信模块对发动机控制器CPU的资源消耗,同时为整个CAN通信软件模块的扩展提供了一个很好的开发平台。     

煤矿老采空区场地残余沉降的预测研究

结合“华美电厂二期工程煤矿采空区场地稳定性评价”工程项目，通过资料收集、现场调查和钻探验证等手段，查明评价场地的地层条件和庞庄煤矿采空区主要工作面的分布和特征。采用概率积分法对采空区影响范围内残余沉降进行了预测，并根据预测的结果对评价场地的稳定性和建筑工程适宜性进行了评价。     

基于ISO15765协议的车载电控单元应用程序刷新系统设计

针对车载电控单元应用程序更新频次越来越快的要求,设计了一种基于ISO15765协议的应用程序刷新系统。该系统采用上下位机的方式,上位机用作人机界面,下位机用作上位机与车载电控单元之间的通信接口。实际测试表明,该系统能成功刷新符合ISO15765协议的车载电控单元的应用程序。     

高压共轨柴油机判缸策略及燃油喷射控制

利用微处理器硬件资源实现曲轴脉冲信号的倍频,提高了喷油正时控制的精度,并设计了不同相位判断模式下的相位判断算法,提高了软件执行效率。针对不同的相位判断模式设计了燃油喷射控制逻辑。试验结果表明,不同相位判断模式下ECU均能快速准确获取发动机相位,燃油喷射精度在0.2°曲轴转角范围内,曲轴转速传感器或凸轮轴相位传感器故障模式下发动机能够维持运转。     

基于场景识别的电动汽车唤醒、休眠策略设计

为合理应用车载低压电能,文章设计了基于应用场景识别的一体化分层唤醒、休眠控制的策略。根据KL30下整车有效唤醒状态按需唤醒电控单元,并引入用车场景预测、提前唤醒电控单元,解决电控单元按需唤醒下用车场景快速切换带来的响应延迟问题;同时,通过场景识别进一步排查无法休眠的电控单元,进行防低压亏电控制。文章应用CANOE?工具仿真了用户遥控解充电枪锁操作及充电口单元无法休眠工况,结果表明,所提出的控制策略能够提高解充电枪锁响应速度,并能够识别出无法休眠电控单元进行防亏电控制。     

基于状态转换的ECU功能测试研究

针对传统设计ECU功能测试用例时无法兼顾输入动作的组合与有序状态迁移的问题,提出一种基于状态转换的黑盒测试用例的设计思想,并结合SCU功能测试用例设计实践,阐明了应用状态转换进行功能测试用例设计的方法和流程,并提供了一整套满足ECU功能测试的软硬件测试系统平台的搭建方案。     

斯太尔重型CNG发动机电控单元的开发

介绍了斯太尔重型CNG发动机电控单元的硬件设计、控制策略以及软件开发。给出该电控单元在发动机上的标定结果和发动机性能参数。试验结果表明,该电控单元可以实现发动机顺序点火、单点连续喷射燃料供给等控制功能,达到了开发目标。     

售后车辆电子模块刷新技术发展概述

电子模块刷新技术可有效应用于售后车辆的维修以及车辆电子控制单元软件的升级更新,可以降低维修成本,提升车辆故障解决的效率。阐述了售后车辆电子模块刷新的基本流程;详细介绍了其发展历程,对每一发展阶段特点作了分析;重点介绍了车联网状态下新型"网盘"刷新技术在电子模块刷新中的应用;最后对汽车电子模块远程在线刷新技术模式进行展望。