Optimisation of stability of vehicle with ABS braking system

摘要

The invention concerns an anti-locking braking-force control circuit for vehicles in which each axle is fitted with at least one wheel-rpm sensor (1, 2, 3, 4) on both sides of the vehicle and in which only one brake-control valve (9) is fitted for control of at least one of the axles, the brake-control valve controlling the brake pressure so that it is the same in all the wheels on this axle. The rpm signals from the sensors (5, 7 and 6, 8) on the left-hand side and right-hand side, respectively, of the vehicle are summed separately in registers (14, 15) and the difference between the register counts compared with a predefined value in a comparator (17). This makes it possible to determine whether the wheels on the left-hand and right-hand side of the vehicle are experiencing significantly different surface adherence. If such a mu -split condition is detected, then the brake pressure to the axle with only one valve is increased rapidly in accordance with a linear function until the slower wheel locks up completely. The brake pressure is subsequently increased gradually in accordance with a second, more slowly increasing, function until a predetermined maximum pressure is reached. During this mu -split condition, anti-locking control is carried out solely as a function of wheel-rpm signals from that wheel which, at the beginning of the mu -split condition, was experiencing better surface adherence.