On an unassuming Sunday in September 2013, the European Commission launched one of the most comprehensive commercial vehicle research projects in recent history.
The tellingly named ‘Transformers’ initiative saw 13 businesses from across Europe – among them illustrious names such as Volvo Trucks, DAF, Schmitz Cargobull, Van Eck and Bosch – tasked with the challenge of developing no less than the truck/trailer combination of the future.
Hoping to enable an unprecedented level of collaboration among some of Europe’s most forward-thinking engineering and services businesses, the brief not only included the use of on-demand hybrid technology, but also the optimisation of airflow and loading efficiency by testing the very limits of heavy vehicle design and material sciences.
Half a decade on, and the results are finally in – summarised in a comprehensive, 93-page mission report that is widely considered the first step into a new era of commercial road transport, and immortalised in a set of high-tech concept vehicles that were recently presented at Volvo Truck’s global headquarters in Gothenburg, Sweden.
The report concludes that by looking at a truck/trailer combination “holistically”, there is a realistic chance to reduce the industry’s energy consumption per tonne-kilometre by up to 25 per cent – without changes to the current European regulatory framework or affecting existing road infrastructure.
Even more importantly, it says that all three areas of focus – load optimisation, aerodynamic improvement and hybrid-on-demand technology – showed sufficient potential for a “viable business case” in the future.
The future is electric
According to German OEM Schmitz Cargobull – which contributed one of two concept trailers, focusing predominantly on energy efficiency – integrated hybrid technology will be key to the trailer design of the future.
Using a standard curtain-sider as a base vehicle, the trailer specialist therefore developed a new kind of Trailer Driveline Management System capable of dynamically distributing energy from a power-recuperating axle to the gearbox, on to a prop shaft and down to the truck’s drive axle. The required 22kWh battery is hidden in between the concept trailer’s l-beams for protection from impact.
The 1,140kg system on Schmitz Cargobull’s energy efficiency trailer can reportedly provide the truck with a 80kW power boost and 200Nm of additional torque, enabling a six per cent decrease in carbon dioxide output.
And, there’s still potential for more, the OEM says. Given the Transformers project still used a traditional diesel truck as a base vehicle, the advent of hybrid engines in heavy-duty trucking could multiply the system’s potential – especially in combination with next-generation EBS systems that are optimised for energy recuperation during downhill driving and braking.
Aerodynamics are key
According to Schmitz Cargobull, aerodynamic optimisation is the second key variable determining the truck and trailer design of the future. If a trailer is equipped with a full aerodynamics kit – including side skirts, under-body deflectors, closed wheel housings, a rear diffuser and a boat tail – and if the corresponding truck has a front spoiler fitted that is as wide as the side spoilers on the cab and chassis, the OEM says significant fuel savings are possible.
The extra weight of the aerodynamics kit, however, does make for a “small penalty” at low velocities, according to the mission report, as the share of the aerodynamic drag in the overall road load is reduced and replaced with inertial and rolling resistance forces that need to be overcome.
Schmitz Cargobull’s energy efficiency concept vehicle also features a movable roof that can be lowered to reduce the front surface of the combination and reduce drag at the rear – in turn also reducing internal space where it is not required.
While this may seem contradictory to the need for load optimisation – in the lowest setting, Schmitz’ prototype has a front end height of 3.5m and a rear low of 3.1m – the OEM points out that it merely meant to give operators the option to change the roof height when the trailer is not loaded all the way to the top, admitting potential savings would be hard to quantify.
Smart loading
As part of the Transformers initiative, Dutch OEM, Van Eck, designed a second concept vehicle focusing mostly on load efficiency – showcasing that additional flexibility may be gained by optimising the internal length of the trailer using smart engineering and new materials.
While detailed information on the second unit is not included in the official mission report, it seems as if the OEM maximised the trailer’s internal capacity by designing a bulkhead with flexible corners – in turn achieving a one-pallet or three per cent plus in load volume over a comparable standard unit.
Just like Schmitz Cargobull, the Dutch company also opted for a configurable roof that can be moved seamlessly into a number of pre-programmed positions using a battery-powered spindle system. Additional details have not been published, however, and Van Eck chose not to share any further information with Global Trailer.
The end of one-size-fits-all
According to the now available mission report, the Transformers initiative proved that the trailers of the future will not only be “vastly more flexible” than current designs – both from an energy-generation and load optimisation perspective – but also capable of interacting closely with the truck up front. The result is a vehicle that is perfectly fine-tuned to the transport task at hand.
“Current semi-trailer combinations are very much a one-size-fits-all solution, being optimised for a limited variation of use cases and for maximum payload,” it says. “At the same time, there is an ever increasing need for optimised transport efficiency for each transport mission. The Transformers project successfully combines a range of innovations in a scenario where future semi-trailer combinations are easily adaptable so that they can be optimised for every transport mission.”
Fast Fact
The development of an industrial standard for the hybridisation of trailers has emerged as a key action item from the Transformers project, especially under consideration of quick commercialisation. That’s why many systems developed under the initiative – including Schmitz Cargobull’s innovate hybrid drive – were designed to ‘open pre standards’, meaning they are expected to form the basis for a subsequent standardisation process.
Fast Fact
Upon conclusion, the European Commission’s Transformers initiative almost instantly inspired a follow-up project. Dubbed Aeroflex, it will be focusing on “aerodynamic and flexible trucks for next generation long distance road transport” and conclude in 2025.