Showing posts with label optimised. Show all posts
Showing posts with label optimised. Show all posts

The new Mercedes-Benz Citaro in detail: Practical and inviting interior


OFFICIAL PRESS RELEASE

Stuttgart/Mannheim, Germany, May 20, 2011

The Citaro already set new standards when it was first launched in 1997, with a passenger compartment that was as cheerful as it was practical. The new Citaro follows in this tradition by setting another milestone in the development of regular-service buses with a multitude of innovations.



New doors save weight and increase strength

The new inward-swinging doors, manufactured in-house, have a lightweight, low-maintenance design, and feature an optimised rubber seal at the bottom for a snug fit when closed. The new sealing concept produces a virtually air-tight seal around the doors, largely eliminating wind noise in the vehicle interior in the process. The new doors stand out for their low weight, sturdy frames and highly accurate fit. The door leaves are individually controllable and are operated separately. Alternatively, the Citaro can be equipped with a new pivot-and-slide door at the front entrance too, which is available exclusively for the Citaro. This door is inclined slightly outwards as it slides forwards, allowing it to pass the nearside exterior mirror without touching it. The characteristics of the new pivot-and-slide door likewise include low weight and high stability.

Lower, well-illuminated entrances

The passenger compartment of the new Citaro has a particularly inviting feel to it. The pleasant experience for passengers begins at the bus stop thanks to the use of broad LED light strips to light up the entrance and exit areas brightly at all doors, both inside and outside the bus. A large plaque bearing the brand logo and lettering, which is integrated into the new door leading to the driver's cab, lets all passengers know as soon as they step on board the new Citaro that they are taking a seat in a Mercedes-Benz.

Sophisticated lighting technology for increased comfort and safety

The new Citaro’s passenger compartment stands out for its bright and cheerful design. This applies to both the colour scheme and the interior lighting concept. The ceiling lamps have multidimensional lenses, meaning their light doesn't just shine down directly, but also reflects off the roof hatches to produce an indirect lighting effect. LED bulbs can be fitted in place of the standard fluorescent tubes as an option. In future, it will be possible to have extra light fittings installed around the edge of the ceiling. This lighting technology can be used to create quiet zones and reading corners within the seating area. The good lighting levels will have the additional effect of reducing the risk of vandalism at the rear of the bus.

Lighting units that can be integrated into the new grab rails on the Citaro are likewise available. The upright grab rails basically feature the same outward-curving shape taken from the predecessor, which served as a model solution for the entire industry. The new uniform distribution achieved by attaching the grab rails to a continuous overhead section to form just two lines gives the interior a more orderly appearance. Straight grab rails are fitted at the front. They are positioned further apart here, giving passengers boarding the bus the impression of more space. The horizontal grab rails are now mounted in front of the vertical rails, which also has the effect of giving the passenger compartment a more tranquil appearance and creates a line for the eye to follow when looking around the interior.

Innovative grab rails with advertising and lighting

The horizontal grab rails are made from extruded aluminium sections and are oval in section. This, together with their larger diameter, makes them particularly easy to grip. The new shape furthermore allows lighting elements as well as exchangeable advertising inserts with clip fasteners to be integrated into the grab rails, paving the way for a brand new form of advertising. The new, wraparound stop-request buttons are easier to find, especially for passengers with impaired vision.

The partition behind the driver’s cab as well as the outer ceiling flaps can now be used as advertising space too. There is also the option of route displays which can be integrated into the outer ceiling sections. Pre-fittings for monitors with a 48.26 cm or 55.88 cm screen diagonal are furthermore provided behind the cross-duct and in the rear section of the bus for information and advertising purposes.

Smaller cross duct, new stowage facilities

The cross duct between the front entrance and the main passenger compartment is much flatter on the new Citaro. This has the advantage of increasing headroom, enhancing the sense of spaciousness and optimising the driver's view of the passenger compartment through the interior mirror. Also new to the passenger compartment are the stowage shelves with closed bases instead of the grilles that were previously used around the grab rails. The stowage shelves and frame can now be painted in different colours.

The modified wheelchair bay that is optionally available offers added protection for passengers with reduced mobility thanks to a raised bulge on the grab rail and a glass retaining wall. Its design blends in harmoniously with the rest of the new Citaro interior. The new and distinctively styled glass partitions are screen-printed to make them easier to see. The shape of the glass panels increases the distance between them and the grab rail, making it easier for passengers to hold on.

A new inner ceiling facilitates ventilation

The new centre section of the ceiling running the length of the passenger compartment has a composed, uniform design with an even perforation pattern that extends into the ceiling segments underneath the roof hatches too. This perforated ceiling allows the passenger compartment to be ventilated evenly over a large area. Fresh air enters through the ceiling segments underneath the open roof hatches. These can be raised open electrically and close automatically whenever the windscreen wipers are operated or the engine is switched off. Like the outgoing model, the new Citaro also offers the option of a highly effective ventilation system with overhead ducting and built-in heater – an unusually elaborate concept in the urban regular-service bus segment. The interior is heated as standard by new sidewall heaters, with the option of convector heating.

Compact air-conditioning system lowers procurement and running costs

Mercedes-Benz now offers the Citaro rigid bus with a new compact air-conditioning system as an additional option to bridge the gap between the familiar ventilation and air-conditioning systems. It takes the form of individual independent units, which are positioned over the roof hatches and do not require any additional cabling other than for supplying power. Thanks to its slight cooling effect combined with uniform movement of the air, the system can maintain a comfortable interior climate at average summer temperatures for Central Europe. The system is regulated according to the outside temperature. Both procurement and running costs are lower than with a conventional air-conditioning system, where the high cooling capacity is attained regardless of the exterior temperature. The refrigeration capacity is 3.8 kW per unit.

The proven seating concept has been retained

The new Citaro has adopted the previous model’s proven seating concept with cantilever mounting. The seats are manufactured in-house. The City Star Eco version is fitted as standard in urban buses, while the Citaro Ü comes equipped with the Inter Star Eco rural-service seat, in view of the longer time that tends to be spent in the vehicle. There are many different variants to choose from for both the seating design and the arrangement of the seats in the passenger compartment.
























Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.

The new Mercedes-Benz Citaro in detail: Safe, weight-optimised construction


OFFICIAL PRESS RELEASE

Stuttgart/Mannheim, Germany, May 20, 2011

A number of decisive advances have also taken place out of sight beneath the attractive exterior of the new Citaro. Although the bodyshell continues to be based on the proven technique of annular frame members – one of the innovations from the first-generation Citaro – it has been made even more rigid to afford passengers yet greater protection in a side-on collision.



Intelligent engineering lowers weight while increasing strength

A series of individual measures have been implemented to give the bodyshell superior strength despite its lower weight. One example is the newly designed pressed sheet-metal parts on the new Citaro, which combine the horizontal and vertical bodyshell elements around the window posts into a single multi-dimensional section resembling the hilt of a sword. Because they are built from a single pressed part, they are both lighter and stronger. Shifting the laser welding further out from the joints has produced a very sturdy connection. The developers have achieved similar results with the new castings for the door portals: although they have been reinforced, their walls are thinner, making them lighter than the previous design.

The expansive glazing on the new Citaro is lighter in many parts too: partially reducing the glass thickness from 4.0 to 3.15 mm compensates for the larger windows’ greater initial weight.
The roof frame is also new: it is based on two longitudinal hoops running almost the entire length, and now weighs just 110 kg on the 12 m rigid bus compared to the previous 137 kg – without sacrificing stability in any way. This new construction furthermore allows flexible positioning of any superstructures on the roof, while also reducing the number of different variants from over 50 to just 15.

New crash element to protect the driver in a collision

An outstanding safety feature that has been integrated into the extended front end of the new Citaro is a crash element to provide additional collision protection. This, together with the strengthened A-zero pillars and a frame design that has been engineered to channel impact forces directly into the substructure, means that the new Citaro already fulfils the requirements of the future pendulum impact test for coaches as laid down in the European ECE R29 standard.

The Citaro already complies with future ECE standards today

The bodyshell of the new Citaro was developed with the future ECE R 66/01 standard in mind too. This specifies a much larger survival space for the interior in the event of the vehicle tipping over than was previously the case. Although the new regulations only come into force in 2017, the new Citaro already complies with them today.

Considerable reduction of load on rear axle

The 55 mm increase in wheelbase length to 5900 mm together with the repositioning of the batteries underneath the driver’s area on rigid vehicles has produced a significant shift in weight, so reducing the load on the rear axle. The leverage effect of the batteries’ new location alone relieves the rear axle of 171 kg of weight. The resulting gain in axle load capacity at the rear is required in anticipation of future exhaust legislation and the heavier assemblies that will need to be fitted in the rear overhang as a consequence. The batteries are furthermore perfectly accessible in their side-by-side arrangement. In the articulated Citaro G, the batteries remain in their previous position on a level with the centre axle, where weight is not a critical consideration.

No heavier despite larger body

Despite the extra body length, the considerable increase in window surface area at the sides and the further major improvements to impact protection on the Euro V version, the new Mercedes-Benz Citaro is lighter overall than its predecessor. At the same time, passenger capacities are at least the same as before – a key criterion for transport operators’ profitability calculations.

Flexible and reliable electrics with PCB architecture

The central electrical compartment in the form of a cabinet behind the driver has also been redesigned. The new electrical system with PCB (printed circuit board) architecture is highly flexible and extremely reliable. It can be easily equipped for additional equipment and is very clearly arranged, resulting in good accessibility for maintenance work too. This dispenses with a great deal of complicated wiring and means there are fewer variants too.

Further improving reliability and durability was also the reason for rerouting cables from the underbody area so that they pass underneath the roof in the interior of the new Citaro, where they are safely protected from environmental influences. It was also possible to reduce the number of attachment points by half in the process, with standardised clips now being used mostly instead of bolts. Cable routing plays a particularly important role in the articulated bus. The switch from the previous S-shaped to the new C-shaped arrangement for routing electrical cables across the articulated section increases operational reliability.











Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.