A hardware-in-the-loop test environment for interconnected ECUs for passenger cars and commercial vehicles 2000-05-0116

The development of state-of-the-art electronic control units (ECU) for vehicles is not only characterized by rapidly growing functionality and rising quality requirements but also by the increasing interconnection of various ECUs. The optimization of the specific ECU function cannot be evaluated any more without considering the effect of this function on other ECUs.

These technical requirements face economic issues like faster design cycles at decreasing costs. It is clear that to alleviate this critical situation, manufacturers must adopt modern development tools, which accompany the design process of ECUs throughout all stages.

Function development and testing of ECUs is still primarily done with specially equipped test vehicles. This approach, however, is costly and time consuming. A guarantee of safe functionality of the ECU at all possible operating conditions of a vehicle certainly cannot be made on the basis of test drives. This is even more difficult in the case of several interconnected ECUs. The manufacturer typically purchases ECUs from different suppliers and it is his task to guarantee the operating safety of the vehicle with all its various ECUs.

Here enter the benefits of hardware-in-the-loop simulation. They allow a complete test of ECUs at all driving situations. Test systems for this purpose are of course not new and are available on the market. However, current test systems are only designed for one single ECU. In this paper, a test platform for a system of interconnected ECUs for a commercial vehicle will be introduced which permits the evaluation of the correct interaction of all involved ECUs.