Frequency analysis of the system of stabilization of vertical reactions on the wheels

Abstract

Increasing importance is given to the issues of road safety. Perfection of modern designs allows automobiles to move at a high enough speed. Taking into account the considerable size of the territory of the state and the variety of roads on which motor transport is operated, there may be areas with a pronounced periodic profile close to a sinusoid with different wavelengths from 0.5 to 1.5 m. On a road with a wave length of a periodic profile of 1 m at a vehicle speed of 36 km / h, the suspension system receives kinematic excitation at a frequency of 10 Hz. This value of the exciting frequency is in the range of real values of the natural frequencies of the wheels in the suspension systems of vehicles (5 ... 12 Hz). The resulting fluctuations in the vertical reactions of the road to the wheels lead to a decrease in the stability of the vehicle's movement. To solve the task of combating this phenomenon, a new method of increasing the stability of the vehicle's motion is designed - the method of controlling the vertical reactions of the road to the wheels when the car moves along periodic irregularities. The paper offers a frequency analysis of the properties of the stabilization system of vertical road reactions to wheels. Various variants of the control organization, algorithms formation using different types of regulators are considered. In particular, control options are considered with the use of proportional and proportional-differential regulators. The issue of the power consumed to control the system for stabilizing vertical reactions of the road to the automobile's wheels is considered, depending on the frequency of excitation by the periodic profile. The performed analysis shows that correctly selected regulators reduce the control forces in the control drive, the power required for control, while the result of control, stabilization of the vertical reaction of the road to the wheel, becomes more significant.