Designing a New, Super-Efficient Semi-Truck and Trailer System
Filed Under: green automotive technology on June 26, 2009
This design incorporates a lot of the design elements that are popularly talked about amongst big truck and transportation engineers. It includes a much larger freight capacity, aerodynamic improvements, trailer skirts, etc. It also includes a few other things that are purely theoretical, but within the realm of possibility for future green tractor-trailer technology.
Designed by Arnold Kioko Muthui, a Kenyan design student with a passion for heavy commercial and transportation vehicles. He features this design, and a few other innovative concepts, at his website akmuthui.sythasite.com.
He calls this design the Highly Sophisticated Transporter, or HST for short. An apt name, I think, given the great number of practical and theoretical concepts included in the design itself. Having driven a big truck for a living before, I can attest that at least some of these are realistic while others would require a real overhaul of how over-the-road transportation takes place.
One of the largest and least theoretical of the concepts for the HAST is the multi-trailer, long vehicle, heavy cargo design. This is not a new idea in heavy transport and is a proven fuel and cost savings technique used in parts of the world now. Australia, for instance, has a long haulage trucking type called “trains” in which multiple trailers are attached to one truck for long, over-the-road movement. In the U.S., however, this would become a safety liability and presents other problems.
For instance, here in the States, our roads and Interstates are optimized (for the most part) for vehicles no longer than 50 feet or so. Most tractor-trailers are currently about 70 feet long in total. The Interstates were built to accomodate the longest military vehicles conceived in teh 1950s, which were theoretical “missile haulers” much like the Russians were using for portable ICBMs. In fact, the entire Interstate system was designed to accomodate the military, not commerce or vehicular traffic as we use it for now.
Another extremely practical design of the HST is its aerodynamics. From the way the tractor itself is designed, both tall and rounded at front, to the full-skirting from nose to tail of the rig is extremely smooth and would ad greatly to the vehicle’s “cut” through the hair. No numbers are offered, but I’d guess it has a much higher coefficient of drag than the average big rig of today.
Of course, a big truck with this number of trailers and joints (articulations) would be impossible to reverse for any length, neither are today’s two-trailer setups like you’ll see mail carriers and so forth using. Any double or triple setup is too articulated to reverse for very far before something bends where you don’t want it.
Muthui envisions this setup carrying a maximum load of about 65 tonnes and being about 29 meters long. To give you a visual on how big that is: a typical tractor-trailer today, which you’ll see on the freeway, carries about 20 tons of freight or roughly 44,000 pounds. Some go as high as 46,000 pounds, but not commonly.
29 meters is roughly 87 feet, which is only about 17 feet longer than current rigs (53-foot trailer plus cab). The trailers are more compact, howeer, in Muthui’s setup to accomodate shorter distances between axles to allow for heavier loads.
Now for the theoretics. Being a sort of alt-fuel afficionado with what I do at Zoomilife.com, I love this stuff.
It’s still diesel-fueled, like most rigs, but the engine powers an electric generator rather than the drive axles. That generator sends power to electric motors in both drive axles. This means that the diesel engine can run continuously at the most efficient speed (RPM rate) possible for maximum output efficiency.
That part isn’t all that theoretical, really, and is a concept being tested and proven right now in prototypes by several companies. The regenerative braking through the motors isn’t a new idea either. Even the solar panels on all of the roofs of the vehicle aren’t a very new concept.
An interesting detail is the battery packs. These are at the joints (called “dollies” in the biz) that separate the trailers and attach one to the other. The space in these joints house the batteries and as you can see in the photo here, the cargo containers are independent of the couplers, so the dolly is actually the rear axles of one container and the front axles of the next.
What that means is that the trailers themselves are independent cargo containers that are modular, so they can be swapped with others in the system, left at the dock, etc. Every professional truck driver knows that the #1 time waster on the road is sitting in docks waiting for load or unload. Many companies get around this by doing “drop and hooks” where the driver drops his trailer in a yard or at the customer’s dock and picks up a loaded trailer and leaves for his next run right away.
This isn’t always possible, however, and is sometimes completely impossible. What this system allows, which won’t necessarily remedy that situation, is the ability to have modularity between trailers–assuming everyone in the fleet has the same rig.
Regardless of how you look at it, Muthui is on the right track with this plan. I’d like to see something similar, but utilizing hydrogen fuel cells or a less design-specific modularity that can be shared amongst manufacturers and fleets. Something with more interchange between designs and less proprietary design.
Overall, though, I like Muthui’s work here and think this is a great concept of how the near-future of over the road transportation is going to become. The HST definitely shows off key concepts in efficiency for trucking’s future.
Related posts:
- Mercedes-Benz Delivers First Natural Gas Semi
- Balqon Not To Be Left Behind: New Highway-Ready Electric Truck
- New Vision Hydrogen Fuel-Cell Truck Video
