ОЦІНКА СТІЙКОСТІ ПРОТИ ПЕРЕКИДАННЯ БАГАТОВІСНИХ АВТОМОБІЛІВ ІЗ ДВОМА ДВОВІСНИМИ ПОВОРОТНИМИ ПЛАТФОРМАМИ

Abstract

The emergence of four-axle cars with two rotating platforms revealed a problem related to the evaluation of the static stability of such cars against lateral overturning. The problem is caused by the fact that traction and braking forces have a point of application not in the point of contact of the wheels with the road on the axle. This means that in the process of turning the platform around its axis, the shoulder of the overturning (upsetting) moment will decrease for a car standing on a side slope. The article presents an improved method for evaluating the static lateral stability against overturning of four-axle cars with two rotating platforms in the transverse plane. The overturning (upsetting) and stabilizing moments are determined separately on the rotary platforms and on the car as a whole. The use of the stability coefficient as an indicator and criterion of static stability made it possible to obtain a mathematical apparatus for evaluating the stability of four-axle cars with two rotating two-axle platforms. The calculation and analysis of the results on the example of a four-axle car with two rotating two-axle platforms, which is on asphalt, a dirt road and off-road, made it possible to state that such a car has high static stability under the condition of overturning. The stability coefficient under the overturning condition is significantly higher than unity, which indicates a large margin of stabilizing moment. The coefficient of stability acquires the smallest value when the angles of rotation of the platforms are close to zero, while when the angles of rotation tend to 900, the value tends to infinity. When the rolling resistance coefficient increases, the value of the stability coefficient decreases for all values of the angles of rotation of the platforms and the side slope of the road. The direction of further research is the improvement of the designs of machines with rotary bridges and platforms and the study of their dynamic properties.