The principle: by constantly comparing data, the micro-computer immediately detects if the speed with which the brake pedal is actuated suddenly exceeds the usual level and concludes that an emergency braking situation exists. The control unit also takes into account the speed and the load status of the bus. In addition, the BAS microcomputer is connected via data bus to the control units of the Electronic Stability Program (ESP®) and other related systems such as the engine and transmission electronics. The BAS electronics "constantly learn while driving" so as to ensure optimum adaptation of the brake pressure in any situation.
It can happen at the critical moment: instead of braking to a standstill and keeping the foot on the pedal, the driver might brake fast, but not fast enough. In an emergency situation like this, the electronic brake assist system (BAS) is immediately activated. It interprets the braking behaviour and in the case of an attempted full brake application, it boosts the braking power to maximum in a split second.
Thanks to BAS the braking distance is considerably reduced. With an average gain in reaction time of 0.4 seconds, the reduction in the braking distance of a coach, assuming a speed of 100 km/h, can be up to 10 metres – which is a huge safety plus in emergencies.