Specifying a middleware for distributed embedded vehicle control systems

The software of electric / electronic vehicle control systems is static in current series vehicles. Most of the systems do not allow maintenance or functional updates, especially in the field of driver assistance systems. Main causes are the testing effort for a software release and the wide variety of different configurations in different vehicle models. In this paper we take a closer look at the requirements for a middleware which allows such updates, verifies new software versions, and adds reconfiguration mechanisms for singular control units and distributed sets of control units. To derive the requirements we consider the general vehicular context with limitations in space, electric power, processing power, and costs together with four exemplary road vehicle control applications (cruise control, automatic parking, stability control, force feedback), and a full x-by-wire target vehicle for implementing these applications. The analysis of these three different sources of requirements results in desired middleware functionalities and requirements, especially concerning runtime timings and update timings. The requirements cover an update functionality with integrated verification, the exchange of applications on singular control units, and the degradation of functionality by switching between control units.