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This research aims to develop an inverse control method capable of adaptively simulating dynamic models of car subsystems in the rig-test condition. Accurate simulation of the actual vibration conditions is one of the most crucial factors in realizing reliable rig-test platforms. However, most typical rig tests are conducted under simple random or harmonic sweep conditions. Moreover, the conventional test methods are hard to directly adapt to the actual vibration conditions when switching the dynamic characteristics of the subsystem in the rig test. In the present work, we developed an inverse controller to adaptively control the vibration exciter referring to the target vibration signal. An adaptive LMS filter, employed for the control algorithm, updated the filter weights in real time by referring to the target and the measured acceleration signals.

Recently the interior sound is actively generated by the active sound design (ASD) device in a passenger car. Therefore, the objective evaluation method for the sound quality of actively designed sounds is required. In previous research, the sound quality of interior sound has been presented with powerful and pleasant for the existing passenger car. This paper presents a novel approach method for the objective evaluation of powerfulness and pleasantness of actively designed interior sound. The powerfulness has been evaluated based on the degreed of modulation and a quantity of low frequency booming of the sound in the paper. On the other hand, the pleasantness is evaluated based on the slope ratio of harmonic orders per octave in frequency domain. These evaluation methods are successfully applied to the objective evaluation of luxury passenger car.

In this paper, the sound intensity and airborne source quantification methods were used to estimate the airborne noise radiating from a gasoline direction injection engine and the contribution of gasoline direction injection engine components to such airborne noise. In order to estimate noise contribution using airborne source quantification, the volume velocity for source should be estimated. In the previous method, the volume velocity has been estimated by using the inverse method. In this paper, the volume velocity is estimated directly. For this work, the sources of noise radiating from the engine are first identified by measuring the sound intensity of the noise sources while the car's engine is running at idle condition. The volume velocities of these sources estimated by multiplying the area of that noise source and directly measured particle velocity.

In the previous paper [1], the impact sound metric is developed for the evaluation of the impact noise in passenger cars based on the wavelet transform. In this paper, seven semantics are subjectively evaluated by 25 participants based on semantic difference method. Two major factors are selected for important factors of impact noise in passenger car. One is comfortable, the other one is impulsive. Two sound indexes for impulsive and comfort are considered for the evaluation of impact sound when a car is driven on 7 difference road surface. These indexes are developed based on new sound metric and other major sound metrics like loudness, fluctuation strength, etc. For the development of these indexes, the interior sounds of 15 passenger car are measured by using artificial head and evaluated subjectively by the participants. These two indexes are successfully applied to the improvement of the impact sound in a test vehicle.