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With the recent advancement in sensing and controller technologies architecture design of an autonomous driving system becomes an important issue. Researchers have been developing different sensors and data processing technologies to solve the issues associated with fast processing, diverse weather, reliability, long distance recognition performance, etc. Necessary considerations of diverse traffic situations and safety factors of autonomous driving have also increased the complexity of embedded software as well as architecture of autonomous driving. In these circumstances, there are almost countless numbers of possible architecture designs. However, these design considerations have significant impacts on cost, controllability, and system reliability. Thus, it is crucial for the designers to make a challenging and critical design decision under several uncertainties during the conceptual design phase.

In recent years, improvement of in-use fuel economy is required with tightening of exhaust emission regulation. We assume that one of the most effective solutions is ACC (Adaptive Cruise Control), which can control a powertrain accurately more than a driver. We have been developing a fuel saving ADAS (Advanced Driver Assistance System) application named “Sailing-ACC”. Sailing-ACC system uses sailing stop technology which stops engine fuel injection, and disengages a clutch coupling a transmission when a vehicle does not need acceleration torque. This system has a potential to greatly improve fuel efficiency. In this paper, we present a predictive powertrain state switching algorithm using external information (route information, preceding vehicle information). This algorithm calculates appropriate switching timing between a sailing stop mode and an acceleration mode to generate a “pulse-and-glide” pattern.

The thermal management system for electric vehicles is developed. Called the Thermal Link System, it consists of a heat-pump air conditioner, a system recovering waste heat from the electric power train, and a heat exchanger between the air-conditioner refrigerant and the power-train coolant water. The recovered heat is used for interior heating, so the amount of power consumed by the heat-pump air conditioner can be reduced. In this system the refrigerant for the heat-pump air conditioner and the coolant water for electric power trains are thermally linked by the heat exchanger, which can reduce the temperature of the coolant water to less than that of the surrounding air. This enhanced cooling function increases the power of electric power trains, or extends the amount of time at full power operation. Here we describe the Thermal Link System's mechanism and effects on energy efficiency.