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Old 09-02-2017, 11:06 AM   #11 (permalink)
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Growing up it was always 18 wheeler around here. Side note, do you know what makes a real tractor a tractor? The engine/transmission is the majority of the frame. So for me it's not just tractor-semi trailer, but semi tractor, semi trailer. Some semis pull a real trailer although usually in combination with a semi trailer, then what?

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Old 09-02-2017, 11:50 AM   #12 (permalink)
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Quote:
Originally Posted by redpoint5 View Post
The aerodynamic problem with tractors isn't in the front, but in the abrupt end of the trailer. The closer to a sideways teardrop you get, the more efficient the design.

I see a lack of side mirrors, which is excellent, but most state laws don't permit a vehicle without mirrors regardless of video cameras. These laws need to be revised.

The shape won't matter too much once automation allows trucks to draft each other in teams.
I just passed state inspection with cameras instead of mirrors. Can't speak for if they were actually supposed to pass me.
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Old 09-02-2017, 03:48 PM   #13 (permalink)
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hood and front end

*It's all in a favorable pressure regime,so there's a lot of creative license available to a designer.
*Everything is softened enough,it looks like,to prevent any local leading edge separation.I don't know about when it's yawed in a crosswind.
*Behind the fenders looks 'draggy.'
*The void area around where the saddle tanks/footsteps would have gone looks draggy as well.
*The driver will probably feel like they're going faster at any given speed,as it seems like the droop-snoot will allow a road view closer to the eye,and more dynamic visually.
*As an EV there won't be the major cooling system drag penalty.
*It's definitely got a 'look.'
*If early-adopters jump on it,it will,over time,come to look more 'normal',the longer all the rest of drivers are exposed to it.A good thing!
*Nice if they'd hook it up to a typical trailer and tunnel test it as a combination.
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Old 09-02-2017, 07:01 PM   #14 (permalink)
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Quote:
Originally Posted by Hersbird View Post
Growing up it was always 18 wheeler around here. Side note, do you know what makes a real tractor a tractor? The engine/transmission is the majority of the frame. So for me it's not just tractor-semi trailer, but semi tractor, semi trailer. Some semis pull a real trailer although usually in combination with a semi trailer, then what?
So many different names for the same kind of vehicle, that it turns out quite confusing for a non-native English speaker.
https://en.wikipedia.org/wiki/Semi-trailer_truck
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Old 09-03-2017, 10:33 AM   #15 (permalink)
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The front fenders need a wider space all the way through; or don't have the slot at all.

I am wondering why the wheels have so much concavity. The rears are singles, by the way.
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I have already seen semi-trailers with single wheels, but it was about time for them to be featured in a tractor unit.
That front fender area is the first thing I noticed. The area where the front fenders squeeze air through that small canyon seems like an aerodynamic bottleneck to me.

And the area on the side of the hood is concave. When I designed my new rig, I made an extra effort not to have any concave radii, only convex radii.

But mayhaps that's just me.

I don't see what you guys are referring to as the wheel concavity. ???

I was one of the first truckers in the world to run those "super-single" or wide base tires on my first truck, way back in 1983, as shown below. We have 8 of them on the new truck, of course. No boat-tails at all, back in the early 80's.

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Old 09-03-2017, 10:58 AM   #16 (permalink)
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Quote:
Originally Posted by aerohead View Post
I don't know about when it's yawed in a crosswind.
I would think it is a cluster-truck in a crosswind.

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Originally Posted by aerohead View Post
*Behind the fenders looks 'draggy.'
Agreed.

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*The void area around where the saddle tanks/footsteps would have gone looks draggy as well.
Yes sir.
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Old 09-03-2017, 11:05 AM   #17 (permalink)
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Here is the rear of the Cummins tractor. The back end of this vehicle looks really cool.

But notice how the side skirts roll around to the rear fascia with those large radii. This is obviously an aero benefit on a non-combination vehicle to fill in the rear vacuum. I would not want to do this on a combination vehicle as I would not want that air on the side of the tractor skirts diverted to underneath of the trailer.

My new truck has 90 degree angles at the trailing edge of the tractor skirts to the rear fascia area to maintain the side air flow of the tractor skirts, all the way down the trailer skirts and the boat-tail. Here is a teaser image.



By the way, we should have some "teaser" images of the new truck that I can post this month. And we have a totally, way cool, Augmented Reality (AR) program that we are working on for the new truck. That AR technology is so amazing. No headset/visor is required, as it is view able on a tablet. I have seen the first version and it is amazing, but we gotta tweak it a little more. I'm hoping to post the AR video sometime later this year.
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Old 09-03-2017, 07:10 PM   #18 (permalink)
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Okay, I have to be the nay-sayer, perhaps a city truck needs to be a cab-over-engine for visiblity and shorter wheelbase, more manuverable in tight quarters.

Perhaps aerodynamics are not a priority in a mostly 35 mph environment.

Just putting it out there.

I would like to see the short box trailer on this, or will it be full length?

Most city trucks have an attached box and no fifth wheel, right?

Example, comparable
Cabovers Gain Popularity in Medium-Duty Truck Fleets - Articles - Vehicle Research - Articles - Work Truck

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Although ubiquitous across the globe, the cabover engine (COE) truck — so named because the passenger cabin literally sits on top of the engine compartment — is a relative niche player in the U.S., where conventional cabs own the lion’s share of the Class 4 to 7 medium-duty truck market.

Yet the COE (also called cabover) has become increasingly popular in recent years for a growing number of fleet applications, including urban delivery, lawn maintenance, pest control, and other jobs. In these applications, the cabover’s signature “flat nose” and wide windshield make it easier — and often safer — for drivers to maneuver in tight city and residential areas.

How do cabovers and conventional cabs compare? When choosing between the two types of trucks for specific applications, what should fleet managers consider?

Review these six comparison points:
I am confused about the description of a Class-7 city truck.

Is there such an animal?
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Old 09-04-2017, 12:29 AM   #19 (permalink)
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Quote:
Originally Posted by kach22i View Post
Okay, I have to be the nay-sayer, perhaps a city truck needs to be a cab-over-engine for visiblity and shorter wheelbase, more manuverable in tight quarters.
Another advantage of the COE layout is the access to the drivetrain components, and it's also the point for big rigs. Not to mention the possibility of keeping it more compact overall while retaining the same load capacities.


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Perhaps aerodynamics are not a priority in a mostly 35 mph environment.
It is possible to enhance the aerodynamics even in a COE rig.
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Old 09-04-2017, 11:39 AM   #20 (permalink)
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Royal Mail testing nice-looking EV vans

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