Oscillatory processes in bus suspension that occur during movement, affect not only on smoothness of motion but also on road safety, especially in relation to the front steering wheels. Based on the computer program AVTO4 which allows us to evaluate the smoothness of the car, we developed a new methods, with the help of which it is possible to calculate the number of detachments of the front controlled wheels of the bus from the road surface, and, in accordance with the results obtained, to select the optimum oscillatory suspension parameters for these driving conditions. In addition, this method also makes it possible to evaluate how the wheel rolls on the road surface varies depending on its vertical oscillations when the bus parameters (the degree of loading) change, as well as the parameters of its unsprung suspension masses (tire damping coefficient, unsprung weight, stiffness tires). Studies were carried out by simulating the movement of a bus along a cobblestone road as the speed of its movement changes. The results obtained are presented in the form of tables and graphs.
The results of the research showed that the optimal oscillating parameters of the suspension of the front controlled wheels of the bus, which satisfy the conditions of smoothness motion, do not always positively affect the number of wheel detachments from the road, and hence the road safety. Therefore, when we choose these parameters, it is necessary to take into account this discrepancy.
The presented method makes it possible to select these parameters at the design stage of any types of vehicles, as well as to change the type of pavement, that is, there is no need to conduct full-scale tests, which saves time and money when creating new vehicle designs.
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