Automotive Electronic Control Units Research Articles

Automotive Electronic Control Unit Ground Line Health Monitoring Method

Electronic Control Units (ECUs) have been used in the automotive industry for decades to control one or more of the vehicle subsystems. The ECUs communicate primarily using the in-vehicle Controller Area Network (CAN) communication protocol. The recent rapid development of connected, electric, and autonomous vehicles expands the number of ECUs and complexity of the CAN network required to integrate vehicle systems and deliver the desired functionalities. This demands increased reliability of the ECUs to ensure for robust vehicle performance. One of the most common ECU failure modes is the ECU ground fault. A ground fault occurs when the ground path in the ECU circuit is corroded, which is usually developed slowly over time. Such failure usually results in various symptoms including ECU incapable of functioning and further impacts the vehicle functionalities negatively. This type of fault can be difficult to detect prior to vehicle functionality loss. It usually involves routinely testing the resistance of the ground circuit, visually inspecting the connectors and wirings, and checking the voltage drop across the ground circuit. Therefore, it is highly desirable to continuously monitor the ECU ground line health status to predict any degradation and thus prevent vehicle functionality losses.
 This paper presents a novel method to monitor the health status of ECU ground line. The method leverages measured CAN voltage data to estimate the ECU ground state of health. The CAN voltage measurements are preprocessed and fed into a real-time data buffer of predefined size. Statistical moments are calculated from the buffered data to generate health indicators, which are then combined to form a fused health indicator. The fused health indicator is used to determine the health stage of ECU ground line. The health stage is classified based on the relationship between ground line degradation level and the ECU communication loss status. The method was developed and validated using actual vehicle data.

Cooling Fan Failure Modes to Enable Development of Automotive ECU Fan Health Monitoring System

Electronic control units (ECUs) are widely used in the automotive industry. Recent efforts to enable enhanced and automated driving requires these ECUs to process and execute computationally expensive algorithms. With these developments, the ECUs now have a higher computing power and thus are at a greater risk of overheating. This may limit the availability of the essential functionalities in the vehicle. Currently, high operating temperatures are mitigated using passive cooling, which allows heat to dissipate without expelling any energy; however, more robust methods are required to enable this new technology. A cooling fan system is one of the desired methods for ECU thermal management, as this type of system draws cooler air from outside and expels the warm air from within. Therefore, the fan health status is critical to ensure ECU availability and reliability for vehicle operation, as when the fans become degraded, they cannot maintain the required airflow to minimize the ECU operating temperature. Traditionally, fan failures are detected by monitoring the fan speed versus the commanded duty cycle, thus it is desired to develop a robust health monitoring method for the fans. Fan failure mode study and fault injection can be used to enable the development of prognostics. Investigating the fan failure modes results in two main categories, which are internal and external. External fan failures include degradation and cracking of the outer casing, while internal failures include motor and ball bearing issues. Fault injection methods were developed based on these failure modes while considering potential operating conditions. For example, the fans were exposed to multiple environmental conditions, such as dust, humidity, and heat. These conditions can potentially trigger both internal and external failures. The data collection was conducted with the fans running in a standalone setup, being controlled by external equipment to ensure that the electronic input values were known. After running tests for 30 days, sufficient data was collected to enable degradation modelling. The data will contribute to the development of a predictive algorithm which will estimate the state of health of the fan based on its performance over time. This paper will discuss the failure modes and the data generated through simulation and fault injection.

Supporting logical execution time in multi-core POSIX systems

Safety-critical automotive applications require predictable and deterministic execution to not miss the timing requirements. Logical Execution Time (LET) is a paradigm already established in the automotive industry to improve the predictability and correctness of time-critical applications. Despite LET being already part of the AUTOSAR Classic standard, no prior work has addressed the design of this model on POSIX-based operating systems, which will be the base of next-generation automotive Electronic Control Units (ECUs). This paper proposes and discusses possible LET design approaches for these novel systems. Different implementations are then evaluated and compared through the WATERS Challenge automotive application running on a multi-core heterogeneous hardware platform.

Low-Cost Data Acquisition System for Automotive Electronic Control Units.

The vehicle testing-validation phase is a crucial and demanding task in the automotive development process for vehicle manufacturers. It ensures the correct operation, safety, and efficiency of the vehicle. To meet this demand, some commercial solutions are available on the market, but they are usually expensive, have few connectivity options, and are PC-dependent. This paper presents an IoT-based intelligent low-cost system for vehicle data acquisition during on-road tests as an alternative solution. The system integrates low-cost acquisition hardware with an IoT server, collecting and transmitting data in near real-time, while artificial intelligence (AI) algorithms process the information and report errors and/or failures to the manufacturing engineers. The proposed solution was compared with other commercial systems in terms of features, performance, and cost. The results indicate that the proposed system delivers similar performance in terms of the data acquisition rate, but at a lower cost (up to 13 times cheaper) and with more advanced features, such as near real-time intelligent data processing and reduced time to find and correct errors or failures in the vehicle.

Ground Fault Diagnostics for Automotive Electronic Control Units

An electronic control unit (ECU) with a floating ground is not able to receive or transmit messages or participate in controller area network (CAN) communication. The absence of any ECU, either temporarily or permanently, negatively impacts vehicle functionalities. The offset ground, which by itself will not affect bus functionalities if the grounding resistance is small, however, may evolve into a floating ground or behave similarly if the resistance is large. In this work, the correlation among ground faults, either offset or floating, and CAN bus voltage or messages are analyzed based on the equivalent circuit models and the bus protocol. A voltage-based solution to detect ground faults is proposed. With the help of bus messages, both faults can be isolated at the ECU level. Considering the inherent system delay between the message fetching and voltage measurement, a normalized voltage-message correlation approach with the bus load estimation is developed as well. All proposed approaches are implemented to an Arduino-based embedded system and validated on a vehicle frame.

자동차 전자제어장치의 열 피로를 고려한 가속수명시험법 개발에 관한 연구

The automotive electronic control unit outputs control signals using electrical signals of various input sensors installed in the vehicle to control the state of the engine, automatic transmission, and electric power steering (EPS). These units are installed inside the vehicle or engine room, and the temperature rises and falls by several tens of degrees due to the heat of the engine and the self-heating of the electronic control unit. Therefore, it was exposed to a thermal fatigue environment due to the difference in the coefficient of thermal expansion between the components, which caused frequent component damage. Solder cracks due to thermal fatigue in electronic control units are a key failure mode. However, because of its great heat capacity, the electronic control unit for automobiles took a long time to attain the desired temperature of high or low, and as a result, the 1,000-cycle test for thermal fatigue life verification required 3,167 hours (or 4.4 months). Therefore, in this study, the thermal shock cycle test time for the verification of the thermal fatigue life of electronic control units for automobiles was reduced by dividing it into two types.

Dynamic model of the temperature downstream to an indirect charge-air cooler considering heat losses to the environment

Thermal management plays an increasingly important role for internal combustion engines due to the high demands on the transient response of vehicles and the legal requirements for pollutants. In particular, the goal to reduce exhaust-gas raw emissions while optimizing fuel consumption can be supported with the help of on-demand temperature control. One strategy to meet the thermal requirements connected to this consists of model-based approaches. For an implementation of such methods on an automotive electronic control unit, a sufficiently high accuracy has to be ensured by the underlying model, alongside the fulfillment of the real-time operation demand. In this publication, we suggest two analytical modeling approaches for heat exchangers with poor thermal isolation with respect to the surrounding. Here we lay a special focus on the real-time capability of the given algorithm for an automotive on-board application. To this end, we utilize the Hammerstein method which allows to divide the overall physical system into a nonlinear stationary part and a dynamical linear one. The former are based on the well-known concept for the dimensionless temperature change of heat exchangers, where we generalize this approach in order to take account of the heat-losses to the surrounding. We demonstrate our model for an indirect charge-air cooler in an internal combustion engine. For both models we find excellent accuracy, with an overall mean-absolute error of 1.23 K and 1.33 K respectively, when compared to experimental data sets containing measurements from the Worldwide harmonized Light Duty Test Procedure.

Two-Layer Bus-Independent Instruction Set Architecture for Securing Long Protocol Data Units in Automotive Open System Architecture-Based Automotive Electronic Control Units

In this paper, we propose a bus-independent hardware (HW)-based approach to secure long protocol data units (PDUs) in Automotive Open System Architecture (AUTOSAR)-based automotive electronic control units (ECUs). Our approach is based on extending previous works that implemented two AUTOSAR communication (COM) application-specific instruction set processors (ASIPs). COM ASIP V1 introduced two instructions to handle the transmission and reception of PDUs no larger than 8 bytes and signals no larger than 32 bits individually through send signal and receive signal instructions. COM ASIP V2 introduced two extra instructions to handle long signals and PDUs of arbitrary lengths. We extended the instruction set architecture (ISA) of our previous ASIPs by introducing six new instructions, in COM ASIP V3, to hash PDUs that contain these signals to authenticate transmission and reception of such PDUs. The experimental results show that COM ASIP V3 can handle (i.e., transmit, receive, calculate hash, or verify hash) a 64-byte controller area network flexible data-rate (CAN FD) frame in 1.575 μs and a 254-byte FlexRay frame in 6.301 μs. These measurements indicate that the throughput of our new COM ASIP is much higher, 42× to 75×, than the throughput required by these communication buses.

Method of Differential-Based Remote Upgrade for ECUs on Vehicles*

In view of the problem that the current update flashing of the traditional automotive electronic control unit (ECU) software highly relies on professional maintenance personnel and external equipment, a method for ECU remote data flashing is proposed to achieve remote and efficient upgrade of ECU software. Furthermore, through the introduction of backup partitions and differential upgrade methods, the problems of lack of fault-tolerant processing, high bandwidth requirements and low efficiency in traditional ECU software update flashing are also solved. In this article, a remote update system is built, including the server-side and the vehicle, and the interface and communication protocols are defined based on HTTPS. The above methods have been verified on NXP IMX 6 platform. Associated testing of the simulation of the ECU by the STM32 and ROCKCHIP demo board has been made based on the CAN and Ethernet simulating the vehicle network architecture. By the real data catching from Ethernet and the CAN, the details of the log file of the programs’ event tracking information are analyzed to obtain the experimental results. The results indicated that the incremental remote data updating system built in this article can remotely update the CAN software accurately and efficiently in all simulation tests, which proved the practicability, accuracy, and efficiency of this method.

Analytical Expressions of Time-Domain Responses of Protection Circuits to ISO Reverse Transients in Automotive Applications

As the use of semiconductors and electronic control units (ECU) in automobiles has increased, electromagnetic susceptibility has become more essential for the reliability of ECUs. Consequently, automotive ECUs are subjected to electromagnetic compatibility tests to control quality. Test pulses for electromagnetic immunity testing in the automotive industry, such as reverse transients 1 and 3a, defined in the International Organization for Standardization (ISO) 7637–2 standard document, are examined. In practice, it is necessary to analytically investigate the performance of the protection circuits against these reverse pulses. In this paper, theoretical expressions of the time-domain responses of the capacitor filter to these reverse pulses are derived. In addition, the expressions of the avalanche energy as well as the time during avalanche mode are presented. The analytical results, validated by LTspice simulation, show that for the case of pulse 1, the reversal battery-polarity protection device after the filter, i.e., a low-voltage power metal-oxide-semiconductor field-effect transistor (MOSFET), is safe despite entering the avalanche breakdown mode. In the case of pulse 3a, the filter can almost completely remove the transient voltage and hence avoid the avalanche effect of the MOSFET. The verified expressions when the suppressed voltage reaches its maximum are very helpful for hardware design engineers to quickly determine whether the MOSFET undergoes avalanche breakdown.

A Multicycle Pipelined GCM-Based AUTOSAR Communication ASIP

In this paper, we explore two pipeline techniques to enhance performance of communication operations in AUTomotive Open System Architecture (AUTOSAR)-based automotive electronic control units (ECUs), and securing these communication operations using an enhanced two-layer process based on the highly secure Galois/Counter Mode of Operation (GCM) algorithm. Our work is based on extending a previous work that implemented three versions of AUTOSAR communication (COM) application-specific instruction set processor (ASIP). We made two pipelined architectures on top of COM ASIP V3 (i.e. COM ASIP V4 and COM ASIP V5). These new versions of COM ASIP are able to handle all operations (i.e. transmitting signals/long signals, receiving signals/long signals, calculating hash, or verifying hash for protocol data units (PDUs) containing these signals using GCM) of our previously implemented COM ASIPs in a pipelined fashion. The experimental results show that COM ASIP V4 has a speedup of 2.25x to 2.39x over COM ASIP V3, and COM ASIP V5 has a speedup of 3.27x to 5.5x over COM ASIP V3. They also show that throughput of these new versions of COM ASIP is much more, 100x to 338x, than throughput required by Controller Area Network Flexible Data Rate (CAN FD) and FlexRay communication buses.

Tool Integration for Automated Synthesis of Distributed Embedded Controllers

Controller design and their software implementations are usually done in isolated design spaces using respective COTS design tools. However, this separation of concerns can lead to long debugging and integration phases. This is because assumptions made about the implementation platform during the design phase—e.g., related to timing—might not hold in practice, thereby leading to unacceptable control performance. In order to address this, several control/architecture co-design techniques have been proposed in the literature. However, their adoption in practice has been hampered by the lack of design flows using commercial tools. To the best of our knowledge, this is the first article that implements such a co-design method using commercially available design tools in an automotive setting, with the aim of minimally disrupting existing design flows practiced in the industry. The goal of such co-design is to jointly determine controller and platform parameters in order to avoid any design-implementation gap , thereby minimizing implementation time testing and debugging. Our setting involves distributed implementations of control algorithms on automotive electronic control units ( ECUs ) communicating via a FlexRay bus. The co-design and the associated toolchain Co-Flex jointly determines controller and FlexRay parameters (that impact signal delays) in order to optimize specified design metrics. Co-Flex seamlessly integrates the modeling and analysis of control systems in MATLAB/Simulink with platform modeling and configuration in SIMTOOLS/SIMTARGET that is used for configuring FlexRay bus parameters. It automates the generation of multiple Pareto-optimal design options with respect to the quality of control and the resource usage, that an engineer can choose from. In this article, we outline a step-by-step software development process based on Co-Flex tools for distributed control applications. While our exposition is automotive specific, this design flow can easily be extended to other domains.

Continuous Automotive Software Updates through Container Image Layers

The vehicle-embedded system also known as the electronic control unit (ECU) has transformed the humble motorcar, making it more efficient, environmentally friendly, and safer, but has led to a system which is highly dependent on software. As new technologies and features are included with each new vehicle model, the increased reliance on software will no doubt continue. It is an undeniable fact that all software contains bugs, errors, and potential vulnerabilities, which when discovered must be addressed in a timely manner, primarily through patching and updates, to preserve vehicle and occupant safety and integrity. However, current automotive software updating practices are ad hoc at best and often follow the same inefficient fix mechanisms associated with a physical component failure of return or recall. Increasing vehicle connectivity heralds the potential for over the air (OtA) software updates, but rigid ECU hardware design does not often facilitate or enable OtA updating. To address the associated issues regarding automotive ECU-based software updates, a new approach in how automotive software is deployed to the ECU is required. This paper presents how lightweight virtualisation technologies known as containers can promote efficient automotive ECU software updates. ECU functional software can be deployed to a container built from an associated image. Container images promote efficiency in download size and times through layer sharing, similar to ECU difference or delta flashing. Through containers, connectivity and OtA future software updates can be completed without inconveniences to the consumer or incurring expense to the manufacturer.

Effectiveness of Noise Suppressing Sheet Material for Mitigation of Automotive Radiated Emissions

Integrated circuit (IC) and printed circuit board (PCB) electromagnetic (EM) modeling methods are becoming essential during the development of automotive electronic control units. Academic and industrial efforts focus on radiated and conducted emissions caused by flaws in PCB design from EM compatibility (EMC)/electrostatic discharge (ESD) point of view, including improper placement, grounding, and shielding of ICs. In this article, the effectiveness of noise suppressing sheet material for the mitigation of radiated emission at global positioning system (GPS) and Global'naya Navigatsionnaya Sputnikovaya Sistema (GLONASS) bands according to U.S. automotive original equipment manufacturer (OEM) requirements is investigated. A few test scenarios that include the NSS material are explored to gauge its performance in near-, intermediate-, and far-field regions, using 3-D full-wave numerical simulations and EMC laboratory experiments.

Performance Evaluation of Attribute-Based Encryption in Automotive Embedded Platform for Secure Software Over-The-Air Update.

This paper aims to show that it is possible to improve security for over the air update functionalities in an automotive scenario through the use of a cryptographic scheme, called “Attribute-Based-Encryption” (ABE), which grants confidentiality to the software/firmware update done Over The Air (OTA). We demonstrate that ABE is seamlessly integrable into the state of the art solutions regarding the OTA update by showing that the overhead of the ABE integration in terms of computation time and its storage is negligible w.r.t. the other overheads that are introduced by the OTA process, also proving that security can be enhanced with a minimum cost. In order to support our claim, we report the experimental results of an implementation of the proposed ABE OTA technique on a Xilinx ZCU102 evaluation board, which is an automotive-oriented HW/SW platform that is equipped with a Zynq UltraScale+ MPSoC chip that is representative of the computing capability of real automotive Electronic Control Units (ECUs).

자동차 전자제어장치(ECU)의 튜닝에 관한 법정책적 소고

자동차 전자제어장치(ECU)의 튜닝에 관한 법정책적 소고

Metal Composite Power Inductors for Automotive Applications [Passive Components

Explains the online demonstration of a new family of metal composite power inductors to address the stringent demands of the automotive electronic control units applications, as well as electromagnetic interference filters.

In-situ service load monitoring of automotive electronic systems using silicon-based piezoresistive stress sensor

It is expected that more and more complex (integrated) automotive electronics will be adopted in systems. These advanced electronics are critical for passenger safety. Documenting the in-situ loading is, thus, very important for accurate reliability prognostics. In this study, we propose a piezoresistive stress sensor to detect the in-situ loading of an automotive electronic control unit (ECU). A load metric directly related to the in-situ loading is defined by considering the in-situ stress values of twelve measurement cells in each sensor. The sensor and the proposed load metric are implemented to document the in-situ loading that results from the local coefficient of thermal expansion mismatch between the electrical components and printed circuit board (PCB) in advanced ECUs. The validity of the proposed metric is corroborated by failure analysis of solder joints of multilayer ceramic capacitors (MLCCs).

Evaluation of Three Different Approaches for Automated Time Delay Estimation for Distributed Sensor Systems of Electric Vehicles.

Deviations between High Voltage (HV) current measurements and the corresponding real values provoke serious problems in the power trains of Electric Vehicle (EVs). Examples for these problems have inaccurate performance coordinations and unnecessary power limitations during driving or charging. The main reason for the deviations are time delays. By correcting these delays with accurate Time Delay Estimation (TDE), our data shows that we can reduce the measurement deviations from 25% of the maximum current to below 5%. In this paper, we present three different approaches for TDE. We evaluate all approaches with real data from power trains of EVs. To enable an execution on automotive Electronic Control Unit (ECUs), the focus of our evaluation lies not only on the accuracy of the TDE, but also on the computational efficiency. The proposed Linear Regression (LR) approach suffers even from small noise and offsets in the measurement data and is unsuited for our purpose. A better alternative is the Variance Minimization (VM) approach. It is not only more noise-resistant but also very efficient after the first execution. Another interesting approach are Adaptive Filter (AFs), introduced by Emadzadeh et al. Unfortunately, AFs do not reach the accuracy and efficiency of VM in our experiments. Thus, we recommend VM for TDE of HV current signals in the power train of EVs and present an additional optimization to enable its execution on ECUs.

Hardware-in-the-loop (HIL) Simulation Technique for an Automotive Electronics Course

Abstract HIL simulation which is part of V-design an industrial approach mainly used in automotive industries for the development of automotive products and Electronic Control Units (ECU). This paper provides an insight into how this industry specific technology is incorporated into automotive electronics course. The course is designed to realize the functionalities of an automotive application built using Model-Based-Design (MBD) with HIL simulation approach. This approach enables to convert the algorithms design and environmental models into real-time applications which can be run on dedicated real-time target hardware connected to physical system. The student learns to systematically create and execute test cases for their automotive sub-system models or components, verify for system requirements and can learn to test their designs for all stages of the Model Based Design process including real-time testing. Outcomes are measured by industry specific rapid prototyping skills demonstrated by the students which made students industry ready.