NVH application research using accelerometers on a chassis dynamometer

Accelerometric tests, similarly to laser tests (with regard to human health) are something of novelty. All standards related to this issue refer to sound intensity (measured using specialised microphones). The work presents results of accelerometric tests conducted during driving cycles on an inertial load chassis dynamometer Maha LPS3000. The object of the research was Mazda 3 1.6 (petrol), built in 2010, mileage 70 thousand km. The tests were related to vibration measurements on a chassis dynamometer using various, forced tractive effort (300, 500 and 700 N). No additional signal processing was used (except for operations necessary to create a spectrum) so as to present the whole vibration spectrum with special emphasis on the resonance frequency of human organs. The article presents vibration amplitude measured at the level of the headrest for three forced tractive efforts: 300, 500 and 700 N. The measurements were made at the speed of 60 km/h in the fourth gear (which corresponds to about 2000 rpm). The obtained results, indicate that the maximum value of harmonics fall in the range 85-95 Hz. Hence, they are resonance frequencies of eyeballs. In addition to this, one can state that the values of these harmonics are higher for higher values of forced tractive efforts. This would mean that seats should be additionally stabilised (dampened) to limit the influence of dangerous vibration on a human organism.