Light, easy and flexible future for heavy commercial vehicles
Naturally light: Topologically optimised cab incl. chassis
It is a well-known fact that nature often comes up with the best inspiration for technical solutions. The EDAG lightweight specialists have based their design on the filigree and yet stable bone structure of mammals to break new ground in designing a light, yet stable cab, including a suitable chassis. Their research and development work has resulted in an optimized frame structure which, apart from integrating a large number of functions, also provides a significant weight advantage compared to conventional construction methods. A specially designed safety cell inside the cab protects the occupants from the typical injury risks in crash scenarios.
The new cab concept has been comprehensively calculated for structure validation by specialists and has been topologically optimised. Based on a steel construction, the cab has been designed to retain its rigidity and meet all crash requirements. Apart from a high level of stiffness and torsional rigidity, today the cab already fully meets the ECE R29-3 standard which will come into force in 2017. Thanks to the degrees of latitude gained in the manufacturing method, it has been possible to optimize the interface between the chassis and cab with regards to package and functions.
The EDAG subsidiary Rücker GmbH (Arbon/Switzerland) came up with the suitable chassis concept. Here as well, a topologically designed structure was consciously selected, not only to make the chassis lighter, but also in readiness for meeting the technical requirements expected in the near future. After all, add-on parts such as fuel tanks and exhaust after-treatment systems are getting heavier, making it more challenging and complex to attach them to the existing ladder frame.
The enclosed cage structure of the chassis concept demonstrated makes better use of the available space in the direction of the road surface, and because of its framework structure, results in rigidity values which are sufficient to absorb the increased load including that caused by the add-on parts.
Apart from weight advantages and improved torsional properties, the filigree cage structure also provides a more flexible connection structure than the ladder frame, for example to integrate an independent front wheel suspension or rear axle tracking.
The truck from the printer
With its additively manufactured 1:4 demonstrator of a truck cab including the suitable chassis, EDAG is presenting a revolutionary prospect for the future of commercial vehicle development and manufacturing. The potential of "3D printing" is impressively great. In particular, topologically designed, complex geometries could be manufactured from data sets in series in a wide range of models without limitations, without tools and in one production step. This paves the way to be able to technically and economically manufacture customised trucks for all operating requirements. "Complexity for free" and "Variants on demand" are attractive advantages of the rapidly advancing technology of additive manufacturing.
At the Geneva Motor Show in the Spring of this year, the EDAG Group successfully initiated discussion between experts about the practical application of 3D printing for structural parts by presenting its vehicle sculpture "EDAG GENESIS". In an analysis, the potentials of promising additive manufacturing processes were examined in greater detail and were discussed with experts from research and industry. Possible candidates for the situation analysis of additive manufacturing were technologies such as fused deposition modelling (FDM), selective laser melting (SLM), selective laser sintering (SLS), right up to stereolithography (SLA).
In the final analysis, an advanced FDM process and of course the SLM which is already established appear to be the most promising candidates for the future topic of "additive manufacturing". In the FDM process, it may be possible in future to make parts of any size, and by introducing endless carbon fibres, attain better rigidity values.
Even though industrial use of additive manufacturing processes is still in its infancy, the revolutionary advantages with regard to greater freedom in development and tool-free production make this technology a subject for the future. From today's point of view, the production of components, and in the next stage modules, is certainly feasible. As for the target of using additive manufacturing to produce complete cabs or chassis: unfortunately there is still a long way to go before this becomes an industrial application. However, it is a feasible option in industry 4.0, which EDAG in cooperation with their customers and partners will actually be able to put into practice with continued exertions in research and development.
Affordable lightweight construction for tomorrow:
With the advanced development study on a light metal design door for a truck, EDAG has proven that steel intensive lightweight construction is also economically viable.
Instead of a multi-layered door shell with numerous reinforcement plates, EDAG lightweight construction specialists are focusing on a door frame reshaped using hydroforming as a central element of door frame construction.
As an option, the door can be covered with monolithic steel plate or sandwich plate. Depending on the design, a weight reduction of up to 19% or 11 kg per cab can be attained compared to a conventional door in monocoque design. Furthermore, the structural properties of the light metal door are impressive. This means that frame rigidity and crash strength are substantially increased. Due to the significantly reduced number of parts and despite choosing a technology which at first glance appears to be costly, on balance the EDAG concept is absolutely cost effective and competitive, and in some variants even undercuts the manufacturing costs of a conventional steel monocoque design.
Man and machine: Power Entry - easy access for heavy trucksDemographic change is a mega-trend - for the commercial vehicle industry as well:
in future, manufacturers and forwarding companies will have to deal with the aging demographic of truck drivers. In particular, frequently having to jump in and out of the cab - which takes a lot of effort when the cab is 1.70 m off the ground - will become an increasing challenge for ageing drivers.
The EDAG group has embraced this aspect and has designed two concepts which will allow them to climb into and out of truck cabs easily and safely. The Power Entry concepts "Lift Plate" and "Power Grip" that they have developed in-house are devices to make it easier to get into and out of the cab with different active principles. These devices can be integrated or retrofitted in standard driver cabs with varying degrees of integration effort.
As on a stair-lift, the driver is transported safely up or down on the convenient "Lift Plate" system when getting in and out of the cab.
The second concept, the technologically less complex power grip, makes it easier to climb onto the bottom rung through an extendable folding step while providing effective weight relief through driven handles to the person climbing up the treads.
Both power entry concepts have now been patented and are readily available to be developed in readiness for start of production in cooperation with a manufacturer or an equipment supplier.