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Journal Article

Mode-Dynamic Task Allocation and Scheduling for an Engine Management Real-Time System Using a Multicore Microcontroller

2014-04-01
2014-01-0257
A variety of methodologies to use embedded multicore controllers efficiently has been discussed in the last years. Several assumptions are usually made in the automotive domain, such as static assignment of tasks to the cores. This paper shows an approach for efficient task allocation depending on different system modes. An engine management system (EMS) is used as application example, and the performance improvement compared to static allocation is assessed. The paper is structured as follows: First the control algorithms for the EMS will be classified according to operating modes. The classified algorithms will be allocated to the cores, depending on the operating mode. We identify mode transition points, allowing a reliable switch without neglecting timing requirements. As a next step, it will be shown that a load distribution by mode-dependent task allocation would be better balanced than a static task allocation.
Technical Paper

Routing Methods Considering Security and Real-Time of Vehicle Gateway System

2020-04-14
2020-01-1294
Recently, vehicle networks have increased complexity due to the demand for autonomous driving or connected devices. This increasing complexity requires high bandwidth. As a result, vehicle manufacturers have begun using Ethernet-based communication for high-speed links. In order to deal with the heterogeneity of such networks where legacy automotive buses have to coexist with high-speed Ethernet links vehicle manufacturers introduced a vehicle gateway system. The system uses Ethernet as a backbone between domain controllers and CAN buses for communication between internal controllers. As a central point in the vehicle, the gateway is constantly exchanging vehicle data in a heterogeneous communication environment between the existing CAN and Ethernet networks. In an in-vehicle network context where the communications are strictly time-constrained, it is necessary to measure the delay for such routing task.
Technical Paper

Efficient Multi-Core Software Design Space Exploration for Hybrid Control Unit Integration

2014-04-01
2014-01-0260
Multi-core systems are adopted quickly in the automotive domain, Proof of concepts have been implemented for power train, body and chassis, involving hard real-time constraints. However, depending on the degree of integration, it can be costly, especially in those cases where existing single-core software has to be migrated over. Furthermore, there seems to be a high level of uncertainty, whether a found solution, with regards to partitioning, mapping and orchestration of software is close to an optimum solution. Some integrated solutions demonstrate considerably less performance, for instance due to communication overhead compared to execution on single-core systems. This paper discusses a methodology, as to how to effectively and efficiently investigate the software architecture design space for multi-core software development.
Technical Paper

Enhanced Injector Dead Time Compensation by Current Feedback

2016-04-05
2016-01-0088
The constant motivation for lower fuel consumption and emission levels has always been in the minds of most auto makers. Therefore, it is important to have precise control of the fuel being delivered into the engine. Gasoline Port fuel injection has been a matured system for many years and cars sold in emerging markets still favor such system due to its less system complexity and cost. This paper will explain injection control strategy of today during development, and especially the injector dead-time compensation strategy in detail and how further improvements could still be made. The injector current profile behavior will be discussed, and with the use of minimum hardware electronics, this paper will show the way for a new compensation strategy to be adopted.
Technical Paper

Improved ECU End of Line Testing using Multicore Microcontroller

2015-04-14
2015-01-0186
End of Line tests are brief set of tests intended to evaluate ECU's in order to ensure correct functioning of its intended functionality. As these tests are executed on the production line, available time to perform these tests is limited. On one hand, faster production demands require these tests and its framework to be designed in a time optimized manner. On the other hand, increase in ECU functionality translates to an increase in test's functional coverage, requiring more time. Therefore the time taken to execute the tests reaches a critical point in overall ECU production. Availability of multicore microcontrollers with increase in clock speed can increase the performance of end of line tests, but design challenges e.g. synchronization do not guarantee a linear performance increase. Therefore, design of test execution framework is absolutely critical to increase performance of test execution.
Technical Paper

The Low Level Driver Design to Improve Dwell Timing of Engine Management System

2015-04-14
2015-01-1621
In Engine Management System, more accurate control is required to improve engine performance. Especially generating the precise ignition signal has a direct effect on better engine performance. In the beginning of this paper, a basic software structure to synchronize the engine crank signal and generate ignition signals will be explained. Several cases which can generate dwell timing error will be introduced based on this software structure. In addition, each impact level for each error case will be described. For cases of major error, compensation ways will be proposed in order to obtain more accurate dwell timing. The compensation ways by both microcontroller hardware and user software will be explained in detail. In conclusion, this paper will show the accuracy of ignition signal which implements proposed compensation ways that can be improved as compared to conventional ignition signal.
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