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Feedback control of combustion phasing based on a crankshaft integrated torque sensor was developed for a spark ignited five cylinder engine. A cylinder individual measure for combustion phasing, called 50% torque ratio, is extracted from the torque signal and used by a spark advance controller. The estimated torque ratio is based on a simplified estimation algorithm where torsional resonances in the crankshaft are neglected, thus limiting the operating range up to a maximum of about 2000 rpm. The torque ratio measure has been compared with the existing measure 50% burned mass fraction, and proven to be a reliable measure for combustion phasing. The spark advance controller has been evaluated by using internal EGR changes as combustion disturbances and an examination of its cylinder balancing properties was performed.

In order to maximise engine efficiency it is of interest to find the peak pressure position (PPP) of the cylinder pressure when controlling combustion engines. Cylinder mounted pressure sensors can be used to measure the pressure, but these are expensive and suffer from limited durability. Alternative pressure estimation methods using cheaper and more durable sensors are needed. This paper shows the performance when estimating the cylinder pressure of a five cylinder SI-engine using a crankshaft integrated torque sensor. An engine model is constructed to be able to eliminate the torsional resonances in the sensed torque signal and the cylinder pressure is reconstructed using a parameterised pressure model. The performance of the estimator is studied in three different simulation cases. Finally, the performance based on measured torque is presented.

Neck injuries in rear-end collisions are usually caused by a swift extension-flexion motion of the neck and mostly occur at low impact velocities (typically less than 20 km/h). Although the injuries are classified as AIS 1, they often lead to permanent disability. The injury risk varies a great deal between different car models. Epidemiological studies show that the effectiveness of passenger-car head-restraints in rear-end collisions generally remains poor. Rear-end collisions were simulated on a crash-sled by means of a Hybrid III dummy with a new neck (Rear Impact Dummy-neck). Seats were chosen from production car models. Differences in head-neck kinematics and kinetics between the different seats were observed at velocity changes of 5 and 12.5 km/h. Comparisons were made with an unmodified Hybrid III. The results show that the head-neck motion is influenced by the stiffness and elasticity of the backrest as well as by the properties of the head-restraint.

By simulating in detail the dry heat loss of the human body, using a clothed, fuil-size thermal manikin whose 17 sections maintain a “skin-temperature distribution” identical with that of a human occupant in thermal comfort, the effect of the vehicle microclimate on sectional heat loss can be rapidly and accurately measured. The VOLTMAN system is based on a digital process-control computer capable of monitoring all relevant physical quantities in the vehicle as well as controlling the manikin. It can be rapidly installed in a standard vehicle, using the existing 12-volt power supply. Extensive field trials in the Arctic areas of Sweden and in Death Valley, California, have already demonstrated its utility and reliability under extremes of cold and heat. As the manikin is maintained at constant temperature it can achieve a new heat-flow equilibrium within a few minutes of a change in the microclimate, permitting a rapid rate of data aquisition.