LAS VEGAS — For the $20 million it spent on the Freightliner Cascadia SuperTruck II program, Daimler Truck North America expects a number of the superior know-how to search out its means into manufacturing.
That’s what occurred after SuperTruck I, an $80 million break up between DTNA and the Division of Vitality that ran between 2010 and 2015. The DOE matched DTNA’s $20 million for SuperTruck II.
The funding from the primary SuperTruck program paid off. Present technology Freightliner Cascadias have a windshield that debuted on SuperTruck I. Gasoline-saving aerodynamic options from the venture confirmed up as choices on the New Cascadia that debuted as a 2020 mannequin.
“We need to give attention to these issues that stand the most effective likelihood for manufacturing,” stated Derek Rotz, DTNA superior engineering director who labored on SuperTruck I and led the SuperTruck II program. “With SuperTruck II, we’ve constructed on these learnings. We didn’t want to start out off with a clear sheet and examine each final nook of the automobile.”
Even because the outcomes of SuperTruck II had been unveiled on the Manifest provide chain convention, DTNA is already engaged on a SuperTruck III program to develop a hydrogen-powered gasoline cell electrical tractor for long-haul trucking that retains most cargo capability.
SuperTruck III outcomes are deliberate for reveal in 2027, across the time Daimler Truck and Volvo Group count on to introduce manufacturing gasoline cell vehicles from their cellcentric three way partnership.
4 focus areas in SuperTruck II
For SuperTruck II, designers and engineers tried to remain near the structure of the present-day Cascadia in selecting what to go away in and what to go away out. 4 areas obtained consideration: enhanced tractor aerodynamics, powertrain enhancements, vitality administration and low-rolling resistance tires.
Every set benchmarks for freight effectivity and a diminished carbon footprint, total targets of the SuperTruck program.
“All these applied sciences collectively drove us to greater than double our freight effectivity on a tractor that doesn’t look radically totally different however performs higher,” stated Derek Villeneuve, supervisor of superior automobile methods.
It’s not a drag
The aerodynamic drag — a measure of the way it slips by way of air currents — got here in 12% higher than SuperTruck I. Engineers didn’t calculate the quantity in opposition to the present manufacturing truck as a result of it could not be an apples-to-apples comparability, Rotz stated.
The redesigned hood, bumper and chassis fairing all complement the present cab construction pushing undisturbed airflow across the truck. The grille, air intakes and doorways had been redesigned to be as seamless and clear as potential.
At freeway speeds, the tractor and trailer routinely decrease a few inches. When the rig slows, the tractor raises again up.
DTNA-developed facet extenders and a roof spoiler additionally activate routinely at freeway speeds to shut the hole between the tractor and trailer to inside 4 inches. They resemble aftermarket extenders from Truck Labs, however Villeneue stated DTNA had been working by itself model.
Cumbersome facet mirrors had been changed by the Stoneridge mirror digicam system. Federal rules prohibit manufacturing facility set up of the system at the moment, however they’re getting nearer. DTNA already pre-wires manufacturing Cascadias to ease their addition within the aftermarket, which regulators permit.
Engine effectivity
DTNA claims SuperTruck II options probably the most environment friendly powertrain Freightliner has built-in right into a truck. SuperTruck II consumes 5.7% much less gasoline than SuperTruck I. A prototype Detroit 13-liter engine options two-stage turbo and interstage cooling paired with a 13-speed overdrive transmission.
SuperTruck II incorporates a break up cooling system that consists of high-temperature and low-temperature cooling circuits working in tandem with two-stage turbocharging and exhaust fuel recirculation cooling on the engine. Navistar launched an identical system on the built-in S13 powertrain provided within the Worldwide LT beginning manufacturing later this yr.
A key profit is decrease engine revving.
“Typical freeway speeds are round 1,100 rpm. We’re discovering SuperTruck II is about 950,” Villeneuve stated. “As a result of the rpm is decrease, it’s quieter contained in the cab.”
48-volt electrical system
Excessive-power 48-volt electrical methods are too costly for many manufacturing vehicles at the moment. They present up in autonomous vehicles the place compute methods require huge quantities of electrical energy. A 48-volt system powered by lithium-ion batteries affords vital advantages in a analysis automobile like SuperTruck II.
Take energy steering for example.
“A typical energy steering system is de facto designed for low pace while you’re parking the truck,” Villeneuve stated. “You want to have a big pump to present you a number of enhance with the intention to steer the automobile.”
However energy steering methods sometimes are overdesigned and inefficient for freeway driving the place little steering effort is required.
“With this technique, we’re in a position to management it such that we will run excessive rpm pump pace to unbelievably straightforward steering at low pace, after which on the freeway you don’t want a number of enhance. We drive all that energy again [into the battery] so that you’re not consuming further vitality.”
The 48-volt battery powers the steering always, even when the truck is driving with the engine off. (Sure, you learn that appropriately.)
DTNA’s EcoSail function can flip the engine off when drive energy isn’t wanted, akin to on an extended downhill descent. The driving force doesn’t must do something. The 48-volt system retains options like air con working. As quickly as energy is required, the engine routinely restarts.
However there’s extra.
The 48-volt starter activates the engine with extra energy and pace. It operates hoteling options in a sleeper cab like microwave opens and leisure methods with out the engine working whereas delivering 12-volt energy for cab lighting and the instrument cluster.
When the rubber meets the street
Because it did on SuperTruck I, DTNA partnered with Michelin to develop tires for adaptive tandem axles that cut back vitality consumption and upkeep downtime on account of much less put on and tear on the tires.
By reducing the friction on the street, much less gasoline is required to keep up the truck pace. Engineers diminished tractor rolling resistance by 12% in comparison with SuperTruck I. Michelin designed tires particularly for the steer, drive and tag axles of SuperTruck II.
Dynamic load shift, which strikes a number of the load routinely from the drive axle to the tag axle, additional will increase effectivity and gasoline financial savings, benefiting from the rear tires’ low rolling resistance. New treads and compounds resulted in 20% much less drive tire put on and tear and considerably improved rolling resistance.
Effectivity as an artwork type
Jeff Cotner, supervisor of design improvement and chief designer, and his crew, sought to inject artwork into the truck as they labored with the engineers.
“We had been impressed by the way in which wind can sort of blow by way of surfaces like snow and sand to create the proper form,” Cotner stated. “The wind will let you know the form it desires the shape to be and we thought that was a superb approach to make the SuperTruck occur. You possibly can really see the effectivity within the shapes that you simply’re .”
And what about that colourful wrap?
“The truck beneath is silver and we would have liked one thing to make it stand out,” Cotner stated.
Mission achieved.
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