Yesterday Citroën revealed details of their next generation Progressive Hydraulic Cushion Suspension as part of an overall engineering and ergo-dynamic strategy the company has introduced as “Citroën Advanced Comfort®”. Playing up on the recognition that for almost a century, the concept of comfort has been closely linked to Citroën and has become a brand signature as had their design or innovation efforts, the acknowledge that the definition of comfort has changed significantly. Today, it encompasses a far broader range of criteria, including light, ergonomics and connectivity.
To date we’ve heard about welcoming interiors, generous equipment, and creative technology in their press releases. But yesterday they laid out their means as to how they will deliver comfort to their customers purchasing not just high-end, but also mainstream models. Here it is:
“CITROËN ADVANCED COMFORT ®”: A GLOBAL APPROACH TO COMFORT
Although it can be summed up in a simple word, comfort is a multi-faceted reality. All sorts of parameters contribute to the well-being experienced by passengers, including: damping, body stability, acoustics, seats, light, space, ergonomics and modular layout. Through the Citroën Advanced Comfort program, Citroën addresses all these aspects of comfort in the development of its models. This approach echoes the grand promise: “Be different, feel good”, which involves finding innovative solutions to enhance passenger well-being. Targeting continuous improvement, Citroën vehicles must also continue to deliver the comfort that is characteristic of the brand and that sets it apart from the rest of the market. This Citroën comfort must be found on all models, whether in the executive or affordable range.
The “Citroën Advanced Comfort” program pursues four objectives:
- filter out any exterior interference, for a cocoon-like ride, with solutions for suspension vibration and acoustics =driving comfort;
- simplify life on board, with generous, space, functional storage compartments and an ingenious layout = living comfort;
- create a smoother experience with intuitive technology, driving aids that can be used every day, and digital continuity between passengers and the car = functional comfort;
- ensure peace of mind by supporting drivers, organizing readouts to display only information that is truly useful, and creating a relaxed interior ambience = comfort of mind.
Through this program, Citroën is restating its credentials and expertise in the field of comfort, with a range of innovations contributing to passenger well-being and a brand signature that is unique on the market. The Citroën Advanced Comfort program is present at each stage of the brand vehicle design process. Guided by changing customer expectations, the program supports the design process in terms of both styling and technology. It is visible on current models and will continue to be a mainstay in the future.
1. Driving Comfort Built on the PSA group’s EMP2 platform
The new C4 Picasso delivers outstanding driving comfort based on type characteristics that are specific to the brand. With its vertical rear shock absorbers, and raised suspension arm joint, for example, it damps out imperfections in the road surface more effectively. The ergonomic design of the seats and the choice of materials also contribute to isolating passengers from road noise and vibrations. Optional heating and massage functions are available. The front passenger can stretch out in a semi-electric relaxation seat with leg support. Last, following studies into road noise, Citroën has increased acoustic comfort and vibration control by improving damping of the front subframe and fitting a dual-material acoustic shim on the rear suspension.
2. Living Comfort
With its optimized space/size ratio, the new C4 Picasso provides generous living space for all passengers. All the seats in the modular cabin are independent, so users can personalize the interior configuration to suit their needs or mood. The storage compartments positioned around the cabin are not only numerous but also welcoming and ingenious. The central storage perfectly illustrates it. With the easily accessible boot and generous capacity, luggage loading is no longer a source of stress.
3. Functional Comfort
The new C4 Picasso features the latest equipment for practical, connected use. Keyless access and start-up already made life easier for the driver. Now, opening the boot is child’s play. To open the hands-free tailgate, you simply wave a foot under the bumper. In terms of connectivity, the new C4 Picasso features a range of intuitive systems, so passengers can connect their smartphone and duplicate it on the central screen (MirrorLink, Apple CarPlay and Android Auto, available at end-2016), browse (7-inch touch tablet, voice recognition) or access the many services available from Citroën.
4. Comfort of Mind
At the wheel, drivers receive input from all directions. To provide assistance and lighten the mental load, the new C4 Picasso provides a range of driving aids for everyday use. Hill-start assist, the semi-automatic Park Assist function or the automatic high beam/low beam switch function provide valuable support. A range of electronic aids, from the lane departure warning function to blind spot monitoring, give drivers confidence in the vehicle’s capacity to alert in the event of an emergency.
The dashboard architecture is unique with its 7-inch touch tablet and 12-inch HD screen for a naturally ergonomic layout that ranks information according to type and importance. The large glazed area (5.30 m²) and spectacular panoramic windscreen also contribute to comfort: the cabin is bathed in light, avoiding any sense of confinement.
THE “CITROËN ADVANCED COMFORT ® LAB”: UNEQUALLED DAMPING QUALITY
The “Citroën Advanced Comfort Lab’” focuses on one of the many and varied aspects of comfort. Designed to filter out bumps and dips on the road, it groups Citroën innovations in this field. When a car drives over a bump or dip, the effect is passed on to the cabin and the occupants in three stages:
- the suspension takes action
- the vibrations are transferred to the body
- the vibrations are felt by the passengers through the seats.
Reflecting this process, the Citroën Advanced Comfort Lab’ prototype features three innovations, one for each form of transmission, in order to reduce the vibrations felt by the occupants and thus significantly improve driving comfort. Citroën has filed more than thirty patents for the technologies implemented by this prototype, but they were all developed to be applicable, from both a cost and production standpoint, to all the vehicles in the Citroën range.
a) Suspension systems with progressive hydraulic cushions
Citroën also has proven expertise in the field of running gear. For over 95 years, the development of comfortable suspension systems has been part of the brand DNA. Over the years, customers have become attached to the comfort delivered by Citroën, which is unlike anything else on the market. Drawing upon its experience and the know-how of its engineers, Citroën has developed a new suspension system, designed to improve damping while maintaining the key brand characteristics valued by its customers.
The operating principle is simple but the result impressive. Whereas a conventional suspension system comprises a shock absorber, a spring and a mechanical stop, Citroën’s system adds two hydraulic stops – one for rebound and one for compression – on either side. In this way, the suspension functions in two stages depending on input:
- in cases of slight compression and rebound, the spring and shock absorber work together to control vertical movement without needing the hydraulic cushions. However, these stops endow the vehicle with greater freedom of articulation to deliver a “flying carpet” effect, creating the impression that the car is flying over any bumps and dips in the road;
- in cases of more significant compression and rebound, the spring and shock absorber work together, bringing in the compression or rebound hydraulic cushions at the end of travel. These stops gradually slow the movement down more strongly to avoid quick stops at the end. Unlike a conventional mechanical stop, which absorbs the energy then partially returns it, the hydraulic cushion absorbs and dissipates the energy. As a result, there is no rebound.
With this innovative technical solution, the Citroën vehicles of the future will deliver an exceptional level of comfort specific to the brand, and always appreciated by its customers. This refinement will not be reserved solely for executive vehicles but will also be available on the city-car segment and in all markets.
b) Structural body bonding
When the suspension has completed the damping process, the energy created by the irregular road surface is transferred to the body. The use of the structural bonding technique will significantly reduce this occurrence thanks to a global stiffness input. Using an industrial process specific to Citroën, the structural parts of the vehicle are bonded together using a discontinuous line of adhesive. An electrical welding is positioned wherever the line of adhesive is interrupted. This bonding technique ensures a hard-bonding assembly without toxic smokes generated by bonding welds. This special bonding technique has a number of advantages:
The first is significantly higher global body stiffness. The improvement in stiffness is around 20% on average. This contributes to isolate it from external vibrations phenomena. A stiffer body will reduce the level of vibrations transferred by driving conditions.
Another significant benefit concerns weight. Bonding makes the body stiffer without making it heavier. The heavier the vehicle, the more complex the suspension damping process for improved comfort.
The third and final advantage of this bonding technique concerns the bead bonding process. This technique allows to reduce the electrical welding work numbers and to control costs. It will not be reserved solely for executive vehicles, but could be used on all Citroën models.
c) Seats inspired by the world of bedding.
Seats are the part of the vehicle most frequently in contact with passengers. It is the seats that provide the first impressions of comfort, when you look at them or get into the car. As well as providing support, they naturally contribute to damping out the various vibrations from the vehicle and the road surface. As part of the development process, engineers study the lines of the seat, in order to respect the curve of the back for a better driving position, and the choice of materials used in manufacture. Foam of different densities and hardness will be used depending on the role of the seat component concerned: support or cushioning.
Adding in a new factor, Citroën looked at practices in the bedding industry, a sector in which shape memory materials represent the latest in comfort. By using several layers of special materials, (polyurethane foam, viscoelastic or textured foam) Citroën has been able to develop shape memory seats that adapt perfectly to the body shape of each passenger and offer an innovative comfort experience in the automotive field. With these properties, the seats regain their original shape from one passenger to the next.
With its progressive hydraulic cushions, structural body bonding and innovative seats, Citroën Advanced Comfort combines three innovations that significantly improve the vehicle’s ability to filter out the bumps and dips of the road.
These innovations reassert all the Citroën expertise regarding comfort. Particular emphasis was placed on the need to make all these innovations gradually applicable to the entire Citroën range, whatever the price of the model. This demonstration vehicle is just one strand of the research pursued by the manufacturer to bring customers a level of comfort unmatched on the market. The new C4 Picasso recently showed that Citroën vehicle can deliver driving comfort, alongside solutions for living comfort, functional comfort and comfort of mind. The brand’s future models will go further in each of these areas, as illustrated by the “Citroën Advanced Comfort Lab” demonstration vehicle in the field of suspension comfort.