Safety systems are becoming increasingly complex, and must be tested as early as possible and integrated in the overall context of the vehicle. In this respect, active safety systems (e.g., emergency brake assist systems) and passive safety systems (e.g., airbags) are distinguished. To test the safety control units early and efficiently, high-performance components are required. Based on a research project, IPG Automotive designed various I/O modules, sensor interfaces, as well as the test system ReSiMa (Replay, Simulation & Manipulation) for hardware-in-the-loop (HIL) testing through the use of which real prototypes (consumption in crash tests) can be saved.
The test system developed by IPG Automotive offers a modular and extensible platform for complex bus and cross-sensor test scenarios. In addition to legal requirements (e.g., number of airbags), other specifications, such as the integration of the emergency brake assist system for pedestrians, must be considered in the future to achieve the full score at the euro NCAP test. In addition, safety-relevant functions gain more and more importance as central sales arguments. Due to the rising test effort and technical specifications, new solutions for the testing of safety control units (SCU) are needed. A special requirement for HIL test systems is a synchronous and reproducible way of working. In an application scenario for safety-related control units, such as a crash test, the use of appropriate components is required. For the test system ReSiMa the hardware modules M407 for SPI (Serial Peripheral Interface) and M406 for PSI5 (Peripheral Sensor Interface) were newly developed.
Funtionality of the test system
• Override of FlexRay signals
• Input of LIN- and CAN-Bus-Traces
• Definition of manipulations (crc, dlc, set value, hold value, change byte)
• Activation of the manipulations in real time
• Input of sensor / mass / crash data
• Emulation of SPI sensors
• Simulation of PSI5 and analog sensors
Advantages of using the ReSiMa solution
• Bus overlapping tests
• Manipulation of the bus signals in real time
• Definition of test scenarios
• Synchronous implementation / manipulation
• Integration of diverse I/O modules
The name of the RealtimeMaker extension ReSiMa - with the approach of the signal and trace based testing - contains the three essential principles of the product idea. Firstly, there is the playing data, where an SCU, e.g., with data sets generated from crash tests, is stimulated. Secondly, the virtual integration of the control unit is important. The third aspect, the manipulation, indicates the need to use variable data, to adapt the signals to the test requirements and test various scenarios. ReSiMa enables the control unit to be stimulated with real crash data and subsequently, without having to create a new real crash test data set, to check its behavior according to the test requirement. As a result, extensive and costly prototype tests can be replaced. By using the presented method, dangerous situations and the subsequent use of safety functions in the vehicle can be detected and evaluated earlier on. This approach contributes to a reduction of the required testing effort while lowering the cost of materials. Using the test system, including the newly developed hardware modules, ensures a time and cost efficient development process and, at the same time, greater safety in road traffic by securing the SCU quality.
Some of the modules that are used specifically for testing safety-critical functions were originally developed in the projects funded by the Federal Ministry of Economics and Energy VISAPS I+II ("networking and integration of safety systems for active and passive safety"). Project partners in the first funding period (2009 - 2011) were the Technical University of Ingolstadt (THI), Continental Automotive GmbH, the Berner & Mattner Systemtechnik GmbH, the Otto-von-Guericke-University of Magdeburg, and IPG Automotive GmbH. The activities were continued in the project VISAPS II, which was attended by IPG Automotive, the THI, and Continental Automotive in 2012 - 2014. The hardware modules were used in the test of airbag control units at Continental for the project. The specific SPI and PSI5 modules developed as a supplement to standard I/O modules such as Analog, CAN, LIN, and FlexRa widen the range of hardware components developed by IPG Automotive. ReSiMa will be available next year. More detailed information on the individual, used, and hardware modules from IPG Automotive (M400 - M441) can already be obtained from the available data sheets on the homepage, under the category hardware.