Improvement of the method of assessing the smoothness of the ride for a vehicle with increased traffic

Abstract

The article analyzes the existing methods of assessing the impact of vibrational loads that occur when cars move on various support surfaces and have an impact on their operational characteristics. The specified methods allow making certain adjustments to the design of the car to increase the smoothness of its movement already at the stage of design work, when creating new cars or improving existing ones. According to the results of the conducted research, it was established that most of the existing methods allow to evaluate the smoothness of the cars’ movement with solid support surfaces. The situation is more complicated in the production of four-wheel drive vehicles, which are absolutely necessary for off-road operation, especially when they are used in combat operations.

On the basis of the conducted research on the determination of smoothness assessment methods, an improved Simulink model of the movement of a four-wheel drive car on the road with a defined micro profile is proposed to obtain the values of the vibration indicators of its suspension.

According to the results of the simulation of the movement of a four-wheel drive car, the efficiency and adequacy of the improved methodology for evaluating the smoothness of the four-wheel drive car for the specified driving conditions have been established. In particular, the adequacy of the Simulink model is confirmed by the comparability of the simulation results on the highway of the same category with the results of other studies. Practical significance when evaluating the effectiveness of the vibration-absorbing characteristics of the seats - the vibration acceleration of the sprung driver's seat compared to the vibration acceleration of the body floor is 2-2.5 times lower, and the vertical acceleration of the hard seats of the crew members is practically 1.5-2 times lower compared to the car body. This allows to select the characteristics and evaluate the efficiency, in addition to the suspension, also the car seats.

Key words: four-wheel drive car, increased cross-country ability, suspension, off-road, smoothness of movement, modeling, suspension system