Rapid design exploration of safety-critical distributed automotive applications via virtual integration platforms

Modern automotive applications such as Drive-by-Wire are implemented over distributed architectures where electronic control units (ECU’s) communicate via broadcast buses. In this paper, we present the concept of virtual integration platform for automotive applications. The platform provides the basis for early analysis and validation of distributed applications, therefore enhancing the current model based development process techniques that are applied to one ECU at a time. The virtual prototype includes both functional and performance (time) models of the application software, scheduling policies, and the bus communication protocols. As a result, since design errors can be found earlier in the design process before the different sub-systems are integrated in the car, savings in both production and development costs can be achieved. The virtual integration platform concept is supported by an integrated IP-based tool environment for authoring, integration, and validation. First, a model of the distributed application is built by composing models of HW and SW components. The models can be either authored or imported from different tools. Functional simulation of the overall distributed control algorithm can be carried out first. Then, the mapping phase can take place: sub-functions of the control algorithm are mapped to architectural resources (CPUs), and zero-time communication links between the sub-functions are mapped to bus protocol delay models. Changing mappings, parameters such as task priorities, and bus schedule enables the exploration of alternative implementations. The validation is carried out by simulating the resulted virtual prototype of the distributed control algorithm running on the ECU network. The design environment shortens design turn-around time by supporting (semi)-automatic configuration of the architecture model (e.g. frame packaging, redundancy level, communication matrix, bus and RTOS scheduling, etc.).