Buses equally need a special set of protective systems in order to face up to the high safety requirements of this type of vehicle – after all, they are used to transport people rather than pallets.
The safety concept of Daimler Buses is a collection of various modules: at their heart are vehicle-specific and operationally oriented items of safety equipment which serve to increase active and passive safety of the buses. Almost all of the assistance and safety systems for buses were premiered on the market in a bus from Mercedes-Benz or Setra.
Specialists for the city: Preventive Brake Assist, Articulation Turntable Controller (ATC), Sideguard Assist
We have developed numerous assistance systems which are tailored to the requirements of urban driving.
An example of this is Preventive Brake Assist – the first Active Brake Assist for urban buses: it can warn of a risk of a collision with moving pedestrians as well as ahead of accidents involving stationary or driving objects. If there is a risk of a collision, the system can automatically apply the brakes within the system limits. The warning cascade and braking intervention are designed for use in urban traffic. Preventive Brake Assist deliberately does not carry out automatic emergency braking. This reduces the risk of injury to passengers standing in the vehicle and for those who are seated but not wearing seatbelts. However, the driver always has the option of applying the brakes fully himself if this is required. Preventive Brake Assist is optional for the entire Mercedes-Benz Citaro and eCitaro family, as well as for the Conecto.
A further specialist system for urban buses is the patented Articulation Turntable Controller (ATC) anti-jackknifing system for articulated buses. These buses are very demanding in terms of driving stability, because the drive system in the rear vehicle section pushes the front vehicle section. Dynamic ATC regulates the hydraulic dampening of the articulation joint quickly when and where it is needed. It takes a number of different parameters into account. If the vehicle reaches a critical condition, such as on slippery or wet roads, ATC initiates the necessary damping of the articulation joint in a split second. The two damper cylinders are activated independently of each other. The articulated bus is then very quickly stabilised within the limits of physics, preventing the vehicle from rocking or even the rear vehicle section swinging out. The result is a level of driving stability which comes close to that of ESP. Whether for the Citaro G, eCitaro G or the CapaCity high-capacity bus, all articulated buses from Mercedes-Benz are equipped with the ATC anti-jackknifing system as standard.
Even when turning off in cities, danger looms. In line with this, Mercedes-Benz and Setra were the world's first bus brands to offer Sideguard Assist with person recognition. The assistance system can inform the driver if an object is located in the warning zone which is monitored on the side of the vehicle – this might be a person or a stationary obstacle such as a bollard. If there is a risk of collision, the driver is warned visually and haptically. Sideguard Assist is available as an option for all buses of the Citaro family, as well as for the Intouro and the high-deck Tourismo coach, not to mention the Setra coaches of the ComfortClass 500 and TopClass 500 series.
Specialist for intercity buses and coaches: Active Brake Assist emergency braking assistant
Mercedes-Benz and Setra can also optionally equip almost all intercity and coaches with Sideguard Assist. A specialist system for coaches and intercity buses with their high speeds is Active Brake Assist (ABA 4). ABA 4 is based on a radar system and can automatically carry out an emergency braking manoeuvre, within the system's limits, to bring the vehicle to a standstill and thus avoid a stationary or moving obstacle. As the first system of its kind worldwide, it also warns the driver of imminent collisions with moving pedestrians and simultaneously initiates automatic partial braking. All coaches from Mercedes-Benz and Setra come as standard with ABA 4.
And now, ABA 5 is in the starting blocks. In its fifth generation, Active Brake Assist reaches another peak of performance. For the first time, ABA 5 works using a combined radar and camera system. The optionally available assistance system can, in addition to the previously known functions, even automatically execute a full-stop braking manoeuvre to avoid a moving person. ABA 5 can identify moving pedestrians as well as people who suddenly stop and stand still. In practice the process is as follows: if there is a risk of a collision with a pedestrian, Active Brake Assist 5 provides the driver with visual and acoustic warnings and simultaneously initiates a partial application of the brakes. If the driver fails to respond, an emergency braking manoeuvre follows automatically, bringing the vehicle to a standstill. On the new Mercedes-Benz Intouro intercity bus, Active Brake Assist 5 has been available as part of the optional equipment since the beginning of 2021. In the future, this emergency braking assistant will also be installed in coaches.
The best possible view for all bus drivers: 360-degree camera system
Sight is safety. On Mercedes-Benz solo buses, the new 360-degree camera system uses four cameras to provide the driver with an all-round view of the entire vehicle surroundings. The camera system is automatically activated when the vehicle pulls away and remains on up to a speed of 35 km/h. It is also active at higher speeds when the turn signal indicator is actuated. A split-screen monitor enables the driver to see the bus from a bird's eye perspective. A second image on the monitor is dependent on the driving situation: depending on which turn signal indicator is activated or if reverse gear is engaged, it switches automatically to the appropriate view. A total of five views are available. Also drivers can switch the images manually when required. The 360-degree camera system is optionally available for urban, intercity and coaches from Mercedes-Benz. Meanwhile, a 270-degree camera system is available for articulated buses. This features three cameras and provides an overview of the left and right-hand sides of the rear section of the bus as well as a view to the rear.
COVID-19: protection for driver and passengers
The extensive protection measures for drivers and passengers against infection in the face of the COVID-19 pandemic provide a very special kind of security. Mercedes-Benz and Setra buses can optionally be equipped with driver protection doors, high partition walls behind the driver and in the entrance areas, as well as contactless disinfectant dispensers. Buses with air conditioning boast active, high-performance particulate filters with an anti-viral functional layer. These active filters are also installed in the air conditioner box as standard. Existing vehicles can be retrofitted with many of these measures. Irrespective of whether on regular service, intercity or coaches, even during the pandemic Daimler Buses offer the greatest possible safety levels.