MULTIPLE ELECTRONIC CONTROL UNITS CALIBRATION SYSTEM BASED ON EXPLICIT CALIBRATION PROTOCOL AND J1939 PROTOCOL

The rising number of electronic control units （ECUs） in vehicles and the decreasing time to market have led to the need for advanced methods of calibration. A multi-ECU calibration system was developed based on the explicit calibration protocol （XCP） and J1939 communication protocol to satisfy the need of calibrating multiple ECUs simultaneously. The messages in the controller area network （CAN） are defined in the J1939 protocol. Each CAN node can get its own calibration messages and information from other ECUs, and block other messages by qualifying the CAN messages with priority, source or destination address. The data field of the calibration message is designed with the XCP, with CAN acting as the transport layer. The calibration sessions are setup with the event-triggered XCP driver in the master node and the responding XCP driver in the slave nodes. Mirroring calibration variables from ROM to RAM enables the user to calibrate ECUs online. The application example shows that the multi-ECU calibration system can calibrate multiple ECUs simultaneously, and the main program can also accomplish its calculation and send commands to the actuators in time. By the multi-ECU calibration system, the calibration effort and time can be reduced and the variables in ECU can get a better match with the variables of other ECUs.

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 Research on the Electronic Control Unit for Diesel Engines

A hardware-in-the-loop simulating platform is developed to avoid designing defects caused by the complicated logical structure and multiple-functional buildup of the dectronic control unit（ECU）in modem diesel engines, and to diminish potential damages on components or human exposure to dangers in R＆D en- deavor. This plat-form consists of a computer installed with software Matlab/Simulink/RTW and dSPACE/ ControlDesk; a diesel engine ECU, and a dSPACE autobox which runs a real-time diesel engine model. A typical model of diesel engine with turbocharger and intercooler is presented. Based on this model our research is carried out with a real ECU to test its software control strategies. Results show that by using the diesel engine model downloaded inside, the hardware-in-the-loop platform can simulate diesel engine＇s working conditions and generate all kinds of sensor signals which ECU needs on a real-time basis. So the ECU control strategies can be validated and relevant parameters roughly calibrated.

APPLICATION OF CIRCUIT SIMULATION IN HARDWARE DESIGN FOR ELECTRONIC CONTROL HIGH PRESSURE COMMON-RAIL FUEL SYSTEM OF DIESEL ENGINE

By means of circuit simulation, hardware of electronic control unit （ECU） of high pressure common-rail electronic control fuel system for diesel engine is designed. According to the system requirements for hardware of ECU, signal-processing circuit of variable reluctance （VR） sensor, filter circuit for input signal, high voltage power circuit and driver and protection circuit of solenoid are simulated as emphases. Difficulties of wide scope of VR sensor output signal, efficiency of high voltage power and reliable and swift driver of solenoid are solved. The results of simulation show that the hardware meets the requirement of the fuel system. At the same time, circuit simulation can greatly increase quality of the design, alleviate design labor and shorten design time.

STRATEGY FOR DIESEL ROTARY ENGINE WITH COMMON RAIL INJECTION SYSTEM

A direct injection low compression ratios diesel rotary engine is designed and studied to find the appropriate application of the electronic controlled high pressure common rail injection system. Current development focuses on the applied fuel injection and ignition strategies, especially concerning the combustion configurations of injectors, ignition source, and combustion chamber. The prototype engine, equipped with Bosch common rail system and high performance electronic control unit （ECU）, is designed correspondingly. Studies show that the integration of a common rail injection system and the main and pilot duel injectors configurations, assisted with glow plug ignition device and flexible ECU, represents a promising approach to improve the potential of the low compression ratios diesel rotary engine. Currently the engine can run at 6 kr · min^-1 steadily and the power is about 68 kW/（4 kr ·min^- 1）.

SIMULATION IN THERMAL DESIGN FOR ELECTRONIC CONTROL UNIT OF ELECTRONIC UNIT PUMP

The high working junction temperature of power component is the most common reason of its failure. So the thermal design is of vital importance in electronic control unit （ECU） design. By means of circuit simulation, the thermal design of ECU for electronic unit pump （EUP） fuel system is applied. The power dissipation model of each power component in the ECU is created and simulated. According to the analyses of simulation results, the factors which affect the power dissipation of components are analyzed. Then the ways for reducing the power dissipation of power components are carried out. The power dissipation of power components at different engine state is calculated and analyzed. The maximal power dissipation of each power component in all possible engine state is also carried out based on these simulations. A cooling system is designed based on these studies. The tests show that the maximum total power dissipation of ECU drops from 43.2 W to 33.84 W after these simulations and optimizations. These applications of simulations in thermal design of ECU can greatly increase the quality of the design, save the design cost and shorten design time

Electronic Unit Pump Diesel Engine Control Unit Design for Integrated Powertrain System

The performance of the electronic unit pump (EUP) diesel engine is studied, it will be used in the integrated powertrain and its multi parameters are controllable. Both the theoretical analysis and experiment research are taken. A control unit for the fuel quantity and timing in crankshaft domain is designed on this basis and the engine experiment test has been done. For the constant speed camshaft driving EUP system, the fuel quantity will increase as the supply angle goes up and injection timing has no effect. The control precision can reach 1°CA. The full injection timing MAP and engine peak performance curves are made successfully.

Advanced ECU Software Development Method for Fuel Cell Systems

The electronic control unit （ECU） in electrical powered hybrid and fuel cell vehicles is exceedingly complex. Rapid prototyping control is used to reduce development time and eliminate errors during software development. This paper describes a high-efficiency development method and a flexible tool chain suitable for various applications in automotive engineering. The control algorithm can be deployed directly from a Matlab/Simulink/Stateflow environment into the ECU hardware together with an OSEK real-time operating system （RTOS）. The system has been successfully used to develop a 20-kW fuel cell system ECU based on a Motorola PowerPC 555 （MPC555） microcontroller. The total software development time is greatly reduced and the code quality and reliability are greatly enhanced.

Development of port fuel injected methanol(M85)-fuelled two-wheeler for sustainable transport

Due to increasingly stringent environmental pollution norms,there is a need for alternate combustion techniques and alternate fuels to keep up with changing trends.One of the viable solutions for India is the adaptation of methanol as a fuel for automotive sector.Therefore,in this study a functional two-wheeler prototype was developed,which uses M85(85%v/v methanol and 15%v/v gasoline)in an electronic control unit(ECU)controlled port fuel injected(PFI)engine.This study included comparative investigations of simulated on-road two-wheeler performance on chassis dynamometer using a gasoline-fuelled motorcycle with stock ECU vis-a-vis M85-fuelled motorcycle using recalibrated ECU.ECU recalibration exhibited that M85-fuelled vehicle was operated at relatively more advanced spark timing compared to baseline gasoline-fuelled vehicle.Performance results showed that M85-fuelled motorcycle produced relatively higher engine power and higher maximum vehicle speed compared to gasoline-fuelled motorcycle.Relatively superior acceleration characteristics(especially at higher speeds)of M85-fuelled motorcycle was another important finding of this study,indicating that M85 provided superior throttle response compared to gasoline.Comparative analysis of raw tailpipe emissions showed that modified M85-fuelled motorcycle emitted relatively higher hydrocarbon(HC),carbon monoxide(CO)and oxides of nitrogen(NO_x)emissions compared to stock gasoline-fuelled motorcycle.However,these emissions can be controlled by using adaptation of suitable after-treatment systems.

A Model-Based Calibration Method of Automotive Electronic Control Unit

This paper presents a systematic method of designing the calibration toolbox of automotive electronic control unit（ECU）based on real-time workshop（RTW）.To break the strong coupling of each functional layer,the hierarchical architecture of the calibration system is divided into the bottom driver layer,the intermediate interface layer and the top application layer.The driver functions meeting the specification of the automotive open system are sent and received in the intermediate interface layer.To reduce the development costs,the portable user codes are generated by RTW which provides a development environment from system simulation to hardware implementation.Specifically,the calibration codes yielded from the controller area network（CAN）calibration protocol（CCP）module are integrated into the control codes,called by a compiler in the daemons to build a corresponding project,and then downloaded into the object board to provide the A2L file.The experiments illustrate that the different drive modules are only needed to be replaced for the implementation of the calibration system applied in different hardware platforms.

WIDE:A witness-based data priority mechanism for vehicular forensics

In this paper,we present a WItness based Data priority mEchanism(WIDE)for vehicles in the vicinity of an accident to facilitate liability decisions.WIDE evaluates the integrity of data generated by these vehicles,called witnesses,in the event of an accident to assure the reliability of data to be used for making liability decisions and ensure that such data are received from credible witnesses.To achieve this,WIDE introduces a two-level integrity assessment to achieve end-to-end integrity by initially ascertaining the integrity of data-producing sensors,and validating that data generated have not been altered on transit by compromised road-side units(RSUs)by executing a practical byzantine fault tolerance(pBFT)protocol to reach consensus on data reliability.Furthermore,WIDE utilises a blockchain based reputation management system(BRMS)to ensure that only data from highly reputable witnesses are utilised as contributing evidence for facilitating liability decisions.Finally,we formally verify the proposed framework against data integrity requirements using the Automated Verification of Internet Security Protocols and Applications(AVISPA)with High-Level Protocol Specification Language(HLPSL).Qualitative arguments show that our proposed framework is secured against identified security attacks and assures the reliability of data utilised for making liability decisions,while quantitative evaluations demonstrate that our proposal is practical for fully autonomous vehicle forensics.