Burian M. Ride comfort of buses in relation to the characteristics of the suspension and seats

Dissertation solves scientific and practical task of assessing and optimizing the level of vibration load acting on the bus passengers in depends of the smooth traffic conditions, class of the bus purpose, and statistical generalization of the average duration of passengers trips. In particular, based on mathematical model, which consist of nine well known from theory equations, was created Matlab Simulink simulational model which allows to detrminate level of vibrational loads that affects on bus passangers at the stage of bus designing. Such approach allows to imapct directly on the ride comfort of passanger transportation. Specific places in the bus salon - near the driver at front overhang, at the middle of the bus base and at the rear overhang was chosen to determine vibration loads. Another characteristic feature of the model consist in usage of equivalent function of statistical distribution to describe the real road profile. In such way quantitative values of vibrational loads in specific places in the bus salon for different types of rear suspension at different load levels was determined by using created simulation model. Obtained results were processed by methods of mathematical statistics and distributed by octave bands for the possibility of comparative estimation of RMS values of vibration loads. According to the modeling results were received and implemented in the project practice recommendations for the selection of the type and characteristics of the suspension and passenger seats in depens on the class of purpose of the bus (urban, local and intercity transportation). Also experimental road test were conducted for the similar buses on the appropriate types of road coverage, after comparison with the results of simulation, showed the adequacy of the model. For those test was created modern set of measuring equipment for simultaneous assessment of vibration loads on passengers from 3 characteristic areas of the bus salon as well as describbed method of measurements and statistic processing of results with delimitation of frequency ranges. The results of those research are the basis for the creating of a new state standard - "Wheeled vehicles.. Test methods and assessment of vibration loads/comfort of passenger traffic".