It has been required recently that diesel engines for passenger cars should meet various requirements, such as low noise, low fuel consumption, low exhaust gas emission and high power. The key to improve the noise is to reduce a combustion noise known as diesel knock noise. An experiment of the noise transfer path from a piston through a connecting rod and a crankshaft to an engine during engine operation revealed that piston resonance was a noise source. To absorb piston resonant energies, new piston structure with Natural Sound Smoother which resonates in the opposite phase to the piston is designed.

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Traumatic brain injuries are commonly caused by blows that produce sudden accelerations of the head. A methodology to define a new global brain injury criterion and thresholds that account for time-dependent and combined translational-rotational kinematics of the head is described in this paper. In total 43 head impact tests with monkeys conducted in the past were reproduced, using a finite element model of the monkey head and neck. The study found that the new criterion predicted concussions and brain tissue strains more precisely than past criteria. A scheme that scales the proposed injury threshold to be applicable for humans is proposed. The new criterion and threshold may then be used in the design of superior protective systems.

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The intermittent feedforward function, termed vibration manipulation function (VMF), was proposed for sampled-data control of an actuator to achieve active suspension of an automobile with road profile undulation. The function can manipulate the position and velocity of a sprung mass of a 1DOF quarter car model in every arbitral operational period. Elongation or force of the actuator can be determined from VMF, which works to suppress vibration of the sprung mass without knowing road profile. Since required power of the actuator can be made smaller and intermittently-feedbacked feedforward control is much easier to be realized, proposed method could provide an alternative guiding principle for active suspension of automobile.

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A urea solution dosing system for Heavy Duty Diesel engines has been developed with improved spray quality of 15 μm droplet size. The system is in production for EURO 6 trucks. This is accomplished by an air assisted dosing system and innovative nozzle design with external mixing.

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