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While many observers think that autonomy is right around the corner, there many unsettled issues. One such issue is availability, or how the vehicle behaves in the event of a failure of one of its systems such as those with the latest “by-wire” technologies. Handling of failures at a technical actuation level could involve many aspects, including time of operation after first fault, function/performance after first fault, and exposure after first fault. All of these and other issues are affected by software and electronic and mechanical hardware. Drive-by-wire and Automated Driving System Availability discusses the necessary systems approach required to address these issues. Establishing an industry path forward for these topics will simplify system development and provide a framework for consistent regulation and liability, which is an enabler for the launch of autonomous vehicles. Click here to access the full SAE EDGETM Research Report portfolio.

The demand for both reduced fuel consumption and increased performance has resulted in the current trend of downsizing and turbo-charging the combustion engine. This started in diesel engines and is being carried over to gasoline direct inject engines. The fuel economy benefit using this strategy is clear, however, the requirements of the launch device are not. One drawback of downsizing and turbo-charging is the effect of lag in boost pressure resulting in a decrease of vehicle performance. This is intensified at increased altitude. One way to reduce turbo lag is by operating the engine at a higher speed. In order to diminish lag, the launch device must allow for faster acceleration of the engine. At the same time, enough engine torque must be transmitted to the wheels to maintain acceptable launch feel. Using a traditional torque converter, the hydrodynamic characteristics can be made looser to allow for faster acceleration of engine speed.