Evaluation of the vibration exposed by the driver and passengers in terms of comfort during the transition from the speed breakers by passenger car

The design of speed bumps, speed humps and raised pedestrian crossings used on the roads should be designed in a way that both reduces vehicle speed and doesn't adversely affect driver/passenger comfort. Contrary to this situation, it has been observed that some of the speed breakers, which are not made in accordance with the standards, don't provide the desired speed reduction, and some adversely affect the driver/passenger comfort. This study explains the design standards accepted in our country and the USA for selected different types of speed breakers and how to make a 3-axis comfort evaluation on the seat surface according to the ISO 2631-1 standard. The study consists of three parts. In the first part, the compliance of 10 speed breakers with design standards was investigated. In the second part, the relationship between vehicle speed, vehicle weight, and the entrance ramp slopes of the speed breakers and comfort were analyzed. In the third part, comfort evaluation was made according to the vertical acceleration values on the seat surface of each driver/passenger first and then the ovtv values. At the end of the study, a comparison of the evaluations made according to the vertical acceleration and ovtv values is given. As a result, it was seen that only speed bump-2 among the speed breakers met the design standards. It was determined that the discomfort on the driver/passengers increased as the vehicle speed and ramp entry slope increased, and the discomfort decreased as the vehicle weight increased. While the comfort level of 87.67% of the speed breakers according to the vertical acceleration values was "uncomfortable", 4% of them were "uncomfortable" according to the ovtv value. These results showed that using the vertical acceleration value alone wouldn't be sufficient for a real comfort evaluation.