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An electrically-driven, intelligent brake unit has been developed, to be combined with a regenerative braking system in electric vehicles (EVs) and hybrid electric vehicles (HEVs) which went into production in 2010 - 11. The brake pedal force is assisted by an electrically driven motor, without using vacuum pressure, unlike conventional braking systems. The actuator can be implemented to coordinate with a regenerative braking system, and to have adjustable pedal feel through use of a unique pressure-generating mechanism and a pedal-force compensator. In this paper, we describe features of the actuator mechanism and performance test results Presenter Yukio Ohtani, Hitachi Automotive Systems

We developed a novel method for reducing the engine noise associated with the high-pressure fuel system in gasoline direct-injection (DI) engines. We focused on the level of noise at idle running speed, because at the idle state, engine noise is the only noise source to the driver. The dominant vibration source of the high-pressure fuel system was fuel pulsation from the high-pressure fuel pump and activation noise of the solenoid-drive injector. To reduce the noise of the idling engine, we focused on the vibration transmission path from the high-pressure fuel system to the cylinder head, which results in noise radiation from the engine block. Next, we focused on the radiation noise associated with the pressurization event of the high-pressure fuel pump. To reduce the vibration transmission from the high-pressure fuel system to the cylinder head, the fuel rail and the injector were isolated from the cylinder head by avoiding metal-to-metal contact.

Functions and sizes of electronic control and software systems in automotives are being increased to achieve better controllability and reduce fuel consumption. A higher safety level is also demanded, so functional-safety standards are increasingly being introduced to in-vehicle systems. In safety critical systems, failure must be diagnosed and a system transited to a safe state when hardware failure occurs. Therefore, the failure diagnosis part of the basic software that takes charge of signal inputs and outputs processing must be verified for high accountability and explanations to a third party. To diagnose failure, the hardware and software that originally operate independently need to cooperate in principle. Hardware and software cooperating systems are not straight-forward to verify, because the combinations of conditions are too numerous for testing.