The Impact of Road Irregularities on the Motion of a Motor Vehicle during Acceleration

Abstract

In this paper the selected results concerning the analysis of the phenomena occurring between the road and the wheels of a motor vehicle have been presented. The analysis was prepared for the simulation of the acceleration maneuver with the 100% (full) throttle along the road with various conditions. The aim of this paper was to analyze whether both the full throttle and the road conditions may affect the forces occurring in the contact area between the wheels of the vehicle and the road, regarding the road conditions and the rear wheel drive of the analyzed vehicle’s model.

Exemplary Determination of the Adhesion Ellipses Based on Simulation of an Accelerating Motor Vehicle

“…deviation after loading were calculated by Adams/Car in relation to the so-called "origo" point (Figure 1), which is a point moving along with the vehicle but located on the road. The vehicle's double seater model used in [21] had the FTIRE (flexible) tires because they allowed running the simulations on the randomly uneven road. This means that a single irregularity can be shorter than the length of the contact area between the wheel and a road.…”

“…The simulations in [21] were run for various road conditions with the initial speed 20 km$h -1 and the road conditions adopted as configurations presented in Table 2, mainly regarding the road surface (dry or icy) and the maximum amplitudes of the random irregularities, which were specified by the intensity parameter. Moreover, the difference between the road profiles for the left and the right wheels was specified by the cor rl parameter, which, in this case, provided almost different profiles for both sides of the vehicle enabling greater reality.…”

“…Moreover, the difference between the road profiles for the left and the right wheels was specified by the cor rl parameter, which, in this case, provided almost different profiles for both sides of the vehicle enabling greater reality. The most difficult conditions of motion were adopted for the configurations 7 and 8 as in Table 2, which was more exactly discussed in [21].…”

“…The aim of this paper was to present the possibility of determining the ellipses of adhesion between the wheels and the road with the use of results obtained for a specific maneuver of vehicle's acceleration simulated in MSC/Adams environment. The selected results of the simulations have previously been presented in [21] by the author and were used as a basis to determine the ellipses of adhesion between the wheels and the road for various adopted conditions of motion. The paper [21] is a source for the research presented here and the main question is whether the longitudinal and the lateral forces, occurring between the wheels and the road, can combine to produce such ellipses and whether the…”

“…The selected results of the simulations have previously been presented in [21] by the author and were used as a basis to determine the ellipses of adhesion between the wheels and the road for various adopted conditions of motion. The paper [21] is a source for the research presented here and the main question is whether the longitudinal and the lateral forces, occurring between the wheels and the road, can combine to produce such ellipses and whether the…”