TerraLiner:12 m Globally Mobile Beach House/Class-A Crossover w 6x6 Hybrid Drivetrain

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7. Electric versus Hydro-Drive Hub Motors?


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Also already posted - google up on MAN-hydro drive, RENAULT-optidrive, POCLAIN hydro-drive [the inventor and patent holder of this], MERCEDES is catching up too and VOLVO has something coming too [being the de-facto step-mother of Renault these days....] for every driven conventional axle replaced by non-driven axle with hydro-drive hubs you save roughly 400kg - maybe not for EVERY axle, I don't know if this number already includes the transfercase/drive.

You still can use the AWD-drive without a time limit, but when it is off you save weight/energy.

Moving along in your post: very interesting contrast between electric motors and hydro-drive hub motors. I have to confess that I don't know that much about hydro-drive motors, and will need to research these further. So many thanks for this heads-up. The costs/benefits of each type of motor are very much worth discussing further in this thread. Same with all of your thoughts about battery size, focusing on energy recovery through regenerative braking, additional solar panel coverage when the vehicle is stopped via expansive awnings, and so on. Lots of interesting stuff worth discussing further, at great length.

Here are some preliminary follow-through links for the names that you gave for hydraulic motors, along with some videos: http://www.truck.man.eu/global/en/f...technology/man-hydrodrive/MAN-HydroDrive.html , http://www.truck.man.eu/man/media/e...ess_website_truck_master_1/MAN_HydroDrive.pdf , http://www.garage-barras.ch/Image/man_hydrodrive_.pdf , http://www.poclain-hydraulics.com/en , http://www.poclain-hydraulics.com/en/systems/trucks , http://www.poclain-hydraulics.com/en/systems/trucks/enhanced-mobility-trailer-wheel-assistance-ref27 , http://en.wikipedia.org/wiki/Hydraulic_drive_system , and http://en.wikipedia.org/wiki/Hydraulic_motor :


[video=youtube;Vib4f79v4kQ]http://www.youtube.com/watch?v=Vib4f79v4kQ [/video] [video=youtube;5eu5QhBZFJo]http://www.youtube.com/watch?v=5eu5QhBZFJo&index=7&list=PLfp_nxCjWatfxyRC CKsct4-eUa1eCBUp_[/video]


Also see the YouTube playlists about Hydro-drives in general (not just the MAN product), at http://www.youtube.com/playlist?list=PLfp_nxCjWatfxyRCCKsct4-eUa1eCBUp_ and http://www.youtube.com/playlist?list=PLq5iMr_Q7XgufhzgOwQnzq2rnpBenTHbA .

In the MAN schematic, it looks like the pump for the hydraulic motor is directly driven by the main diesel engine:





So you seem to be arguing for a fairly conventional drive train, in which a diesel engine drives one axle for highway driving, and the vehicle still has a large transmission. But hydraulic motors kick in to provide added torque and all-wheel drive for off-road or bad-road travel. Is this your position? If I am mistaken, please correct me.

This idea generates some questions. First, which axle should the diesel engine drive in the course of normal highway travel? Presumably the rear, as per this MAN schematic? Second, as such, the vehicle would still need a rear differential. But are other options possible? The hydraulic motors seem to mount individually as hub motors. So in theory at least, they could mount on the rear wheels, with the diesel only directly driving the front wheels? However, although any number of cars exist that are front-wheel drive, very few trucks are -- see http://en.wikipedia.org/wiki/Front-wheel_drive and http://en.wikipedia.org/wiki/Automobile_layout#Rear-wheel-drive_layouts .

If you have any blueprints, schematics, or images of what a typical 4x4 and/or 6x6 set-up would look like, with hydro-drive motors installed instead of all-wheel drive, please post!!

Next, I get the impression that you are generally disposed against a serial hybrid solution and electric motors. It would be great if you might be willing to provide an itemized list as to why.

One of the main reasons I am in favor of a serial hybrid solution, in the case of an expedition motorhome in particular, is because the motorhome must already have a massive battery bank. And so too maximal solar, as well as a diesel generator. Like egn, I disagree with Earthroamer's position that a supplementary diesel generator is unnecessary. Yes, even if one does have maximal solar and high-output dual alternators.

So it seems that a natural "next step" would be to combine the supplementary diesel generator with the main diesel engine, as a single large 120 KW generator (as per the Jepotnik), producing power that drives electric hub motors. Ergo, a serial hybrid. Furthermore, electric motors are a kind of natural application for regenerative braking, because when put into reverse, they function like alternators and generate electricity -- see http://auto.howstuffworks.com/auto-parts/brakes/brake-types/regenerative-braking1.htm . Of course as the short web-page just referenced suggests, in actual practice it's more complicated than that. But that's the general idea. And so too, electric motors might eliminate any need for a low-hanging differential, as one participant suggested earlier in the thread (I can't remember who....?). And finally, electrical motors build in redundancy, especially if there are two or more of them. Perhaps one driving each axle (in a 4x4 or 6x6 arrangement), as recommended by egn and Haf-E. Or perhaps one driving each wheel, thereby eliminating any need for a low-hanging differential? As suggested further along, design for redundancy seems the future, not design for self-repairability.

I am still trying to get up to speed as regards all the more "exotic" power train possibilities. But it would be very interesting to hear more from you about these questions in particular (as opposed issues like window size, curvilinear aesthetics, or motorhome height.... i.e. issues where we will have to agree to disagree.) And it would be interesting to know why you want to advocate a much more conventional sort of solution, in which the diesel engine still directly drives an axle, and is otherwise supplemented only by hydraulic hub motors.

By the way, "Renault optidrive" proved less promising as a reference, and only produced webpages for some of Renault's bigger trucks. Do you have a good link for Renault? And any weblinks for possible Mercedes and Volvo hydraulic motor solutions?


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8. Multi-Fuel? ICE versus Microturbine?


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You will have to balance the battery size, between storage capacity for at least 18 hrs to operate the camped vehicle and charging technology so that you can take advantage of the most efficient output range of the diesel generator. Optimize for MAX DIESEL storage capacity (no matter if you use a diesel engine or turbine, a ROAD-destined turbine will hardly ever be Jet-fuel powered....).

..................

Multifuel-capability? FORGET IT! I don't know of ANY Multifuel-motor out there that keeps its efficiency compared to any dedicated-fuel engine.

Whatever you think you might gain by being able to buy cheaper alternate fuels you WILL loose on efficiency, complexity and reliability elsewhere!

Fully agreed that I will want the vehicle configured for "MAX DIESEL": a 1500 liter tank, if possible. And I can really see your point about the efficiency problems that multi-fuel capability generates, as well as your excellent and well-argued points about the power-cut-off point where diesels become more efficient than turbines.

As for engine weight, given the existence of the Jepotnik gen-set that produces 120 KW, and that weighs just 350 kg, I find myself swinging strongly in the direction of a rod-and-piston diesel generator solution, and not a microturbine generator solution.


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9. Top Speed?


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Bio! If you are out travelling - you will HARDLY EVER want to go 140 - especially with a BIG RIG! I did 130km/h once with a 18m tractor trailer in old East Germany (don't tell anyone!) with brand-new Scania 143 - 400hp - just short of red line rpm - fantastic, I think this was 1989!! But this was a HIGHWAY-rig!!

I wonder what the average Touring/Travel speed of the Big-Rig-Owners here is?

I suppose if you plan for a max of 120 it will be hardly ever used - going electric of course has a lot of flexibility here.

Using the above mentioned Tires - I doubt these will like your speed proposal either!
Look up what a common tire/wheel-size is for the purpose - considering you WANT some serious ground clearance - probably some R22.5 - I assume....

Considering, that you already specify "additional mobility" - I suggest to stick to common and efficient tires, like High-Grip Road tires (Gravel pit trucks, etc...) though I would go for the tallest ones available.

Save the Michelin-Super-X for the trailered "additional mobility"!

.........

What I say - forget the 140km/h!!!

It's very interesting that you say "forget the 140 kmh". This maximum speed was campo's proposal, so I just repeated it. Mañana, for instance, only has a top speed of 110 kmh.

campo: if you are reading this, why did you propose 140 kmh?

And egn, likewise, if you are reading this, do you think 140 kmh is at all necessary for a large motorhome? Should 120 kmh suffice, as suggested by thjakits?


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10. Windows and Walls


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You want to re-think those very big windows - see previous post!

.....and those 6m thick walls!! You probably meant 6 cm???

As for window sizes, here seems another place where we will simply have to agree to disagree. I know how you feel about large windows, and I understand your position. But I still disagree with you. The Kimberley T3 Caravan is an off-road camper, and yet it has enormous windows. See below. Mañana also has large windows, as large as those found in more regular, mainstream motorhomes. And yet Mañana traveled all over Australia, and down most of Australia's more famous dirt tracks, with the major exception of the Canning Stock Route.

So probably best to give windows a rest, don't you think?

It's worth remembering that this project is supposed to be innovative, not merely based on "technology available right now, and previously used in a motorhome application". So although I still have to do the research, I see no reason why large triple-pane windows could not be specified, for all windows except the front windshield. Furthermore, as I have already indicated, I need to contact Bürstner to find out the R-value for the windshield on their new "Panorama" motorhome.

campo is the thermal engineering expert, and he seems to see no problem, in principle, with large windows -- at least from a thermal perspective. I will be gradually working out the thermal consequences of large windows and skylights in concert with campo, over in the "Camper Thermal Engineering Thread". But needless to say, I will be inclined to go with the biggest windows I can get away with reasonably, from a thermal perspective.

Sorry about the typo regarding wall thickness: clearly I meant 6 cm, instead of 6 m. I've gone back and corrected it. Many thanks for noticing this typo!


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11. Absolutely not Air-Transportable


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Mate!! NO worries - if you really want [air-transportability] - I have the connections to get you air-transport for anything you can fit on a road (2.5 m wide and less than a 100 tons total)!! If you want to get brought in on the spot you can go bigger but need to stay below 20 tons.

Question is if you have the dough to pay the service and will survive seeing the invoice!

Interesting that you claim that almost anything is air-transporatable, as long at it is 20 tons.

But again, for me personally, air-tranportabiliy has never been a consideration. Air-transportabiilty is absolutely not a design objective for me. I have no interest whatsoever in air-tranportability.

I cannot be any more clear than that......


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12. Slide-Outs and Pop-Ups. Swing-Outs?


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Pop-up will probably not help with the weight - but I do agree this is a great idea to make it roomy for longer stays.

But then get on it and do slide-outs too - properly designed they ARE reliable and not that heavy.

Here you remarked that properly designed slide-outs can be very reliable, and not that heavy. Care to elaborate? I actually do have some slide-outs in mind, but would first like to hear what you have to say about how these might be best designed for an expedition motorhome. For instance, would you go with hydraulic slide-outs, or electric winch-driven slide-outs?

And what do you think about the "swing outs" on the Maxi-Mog trailer and the Kiravan?










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Do these swing-outs seem like more "bad-road-capable" ways to expand camper space horizontally, than the more standard kinds of slide-outs?

Note that I am already fairly familiar with most of the manufacturers of slide-outs, eg. Lippert Componennts, HWH, Valid, Powergear, etc. So please begin from the assumption that I am up to speed regarding basic distinctions; you don't have to educate me about them. Rather, I am really curious to know what you might think would be a particularly good slide-out system for an expedition-grade, "bad-road" motorhome. And why.

For instance, I was reading on Newell's website that its slide-outs, made by Valid, have automatic pneumatic seals. A thin "bladder" inflated by air runs around the entire slide-out, sealing it off once extended. This seems very important vis-a-vis keeping out dust in the Sahara, or cold in Siberia.


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As for the weight of the Unicat-style pop-up, I am imagining the whole thing made of carbon fiber, much like the recently released GCT CR-1 all-carbon-fiber motorhome -- see http://www.gctrv.com/CR-1-Carbon-Fiber-RV.php , http://www.autoblog.com/2014/04/04/carbon-fiber-rv-caravan-worlds-first-video/ , and http://www.wired.com/2014/04/gct-cr-1/ .


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13. Biomorphic, Curvilinear, and Art-Deco-inspired Design.


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Well "Mr. Colani #2" - I am afraid you will have to do a LOT off soul-searching - if you REALLY want to design something according to the discussed list - not exactly highly compatible wishes here!

The old VW bus might have been quite a ride and I had the pleasure to go places with one myself (not mine, but I drove it!), not exactly scale-able though.

Now take the newer Synchros - scale them up and you got - a very straight 'n square box again!!

As for the "square and boxy" versus "biomorphic and curvilinear" issue, here again I think that you and I will simply have to agree to disagree.

Agreed?

There is really no point in belaboring the point further, don't you think? In this thread I will continue posting examples of biomorphic and Art Deco designs that I love, and perhaps you will continue to write that only square and boxy shapes as per the VW Synchro are practical. But in future, I will probably no longer have time to respond to your rejoinders along these lines........ In future, please consider biomoprhic, curvilinear, rotund, and Art-Deco exterior styling as a "basic datum" of this thread, just like "torsion-free frame" and "fully integrated".

Sure, maybe more curvilinear design seems terribly impractical from your perspective. And no doubt you think you are dead right on this score, and that I should change my mind immediately, converting to your point of view. But it just ain't gonna happen. A more curvilinear design is something that I am fundamentally committed to. And I signaled as much at the very beginning of the thread; just reread the first few pages.

But don't worry, I do not have anything really extreme in mind. And personally speaking, I do not like Mr. Colani's trucks. If you look through the thread, you will see that I myself have not posted anything by Colani. Colani is the extreme case of curvilinear. And so it's a "straw man" argument to use Colani as a paradigmatic instance of what curvilinear design means. There exists a vast spectrum of design possibilities between a boxy Unicat or Actionmobil at one end, and Colani at the other.

I am merely imagining "curvilinear" to the extent that more mainstream motorhomes are somewhat curvilinear. Or, just a bit more curvilinear than mainstream motorhomes, but not much more. And certainly not extreme-curvilinear as per Mr. Colani's trucks. But yes, much more curvilinear than a boxy UniCat or ActionMobil. After all, that is partially the point of this exercise in aesthetic design, as opposed to mere engineering: to get away from the "Kombat-Kamping", militareseque, butch-macho, boxy-rectilinear appearance of many Unicats and Actionmobils. If you read through the thread, you will see that this has been a running concern or "leitmotif" from the very beginning.

Now if you actually like the "Kombat Kamping" aesthetic of Unicats and Actionmobils, more power to you. You are entitled to your aesthetic taste. But it is not my taste, and it is not the taste of most people, who tend to think that Unicat and Actionmobil vehicles are ugly. For most people, these look like garbage trucks at best; militaresque troop transports at worst. You may disagree, and again, you are entitled to your taste. But I am simply not willing to accept an argument that tries to elevate a personal aesthetic preference, to the level of a practical necessity. Lots of beautifully shaped, more curvilinear caravans and truck-campers have weathered off-road and Third-World travel just fine.

As for the VW Kombi Microbus, here too, you and I will simply have to agree to disagree. I think the VW Kombi can be "scaled up". And if you look at the Kombi closely, it's really just a box, too. But a very nicely curved, beautifully shaped box.....:sombrero:

Think of it this way. In the "Camper Thermal Engineering" thread I posted abundant images of the Kimberley T3 off-road Caravan -- see posts #92 to #95 at http://www.expeditionportal.com/for...-High-Altitude-Arctic-Antarctica-Tibet/page10 . This is a genuine off-road product, and yet it has an exterior that is certainly curvilinear. Much more curvilinear than the standard box at the back of a Unicat or Actionmobil:






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If these beautiful curves were not "practical", then why did Kimberley design the T3 this way? There is certainly this to be said: because of those curves, the T3 is very aerodynamic and easy to tow.

Or consider the truck-campers just recently posted above. No doubt the management at ORC will say that they had no choice but to create a boxy, rectilinear design composed out of flat panels. No doubt they will protest very loudly that only their design is truly "practical."

But this cannot be true, because clearly there is a choice to be made here: the videos of Azalai campers posted just above prove that there is a choice. The Azalai campers are far more curvilinear and rounded at the corners, and it's clear that Azalai uses molds to make them. Azalai is a successful French company that has sold lots of campers, campers that have traveled all over the world. So if a representative from ORC were to tell me that more curvilinear design is simply not possible, and that it is "impractical", I would thank him for his time, and would buy an Azalai instead.

Personally, I think this issue is more a matter of taste and pocketbook, than it is a matter of "practicality". The Azalai probably costs more than the ORC, because all those lovely rounded corners require molds. But if the Azalai is one-piece construction without seams, then even from a "practical" point of view, it would probably prove better in the long run than the rectilinear ORC. So sorry to disappoint you, but I simply do not agree with your perspective. Yes, once again, I fully understand your perspective. But I still do not agree with it. I can think of too many examples of better-designed, more curvilinear products intended for off-road use, to be able to accept the line from Actionmobil or Unicat that their boxy-rectlinear designs are an absolute practical necessity for expedition motorhomes.

Again, I would be wiling to agree that rectilinear construction is a cost necessity, if one wants a bespoke motorhome built-to-order by hand, from scratch, by Actionmobil or Unicat. But if there were a limited production run of fully integrated motorhomes, molds could be made. And so the end product could look much more like a Kimberley T3 Caravan or an Azalai.

The proof is there: these products exist, and they sell.


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14. Roll-Over Protection


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Have a look at US-SCHOOLBUS tech (very old and simple) for a combined frame/monocoque/space-frame structure!!

Prevost is probably the most expensive COACH design in the US - NO frame at all! Don't like it, because a semi-serious accident will most likely compromise the whole structural integrity. US-SCHOOLBUSES are built as they are, because the HAVE to survive multiple flips/roll-overs and stay together - if you have a serious accident with a US-SCHOOLBUS you most likely won't be pretty anymore, but rolling under your own power!

As for roll-over protection, please take a look at the images of the MAN Neoplan space-frames posted earlier in the thread: post #274, at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page73 , and also see the Neoplan website that discusses "safety" at http://www.neoplan-bus.com/cms/en/skyliner/sicherheit/skyliner_sicherheit.html . The red bits are rollover protection:





But thanks for the reference to old school-bus designs. Agreed, it would be good to look further into Bluebird, one of the companies that continues to make the classic school-bus -- see http://en.wikipedia.org/wiki/Blue_Bird_Corporation , http://en.wikipedia.org/wiki/Blue_Bird_Wanderlodge , http://www.blue-bird.com/all-american-fe-diesel.aspx , http://www.blue-bird.com/all-american-product-literature.aspx , http://www.blue-bird.com/sigma-transit-bus.aspx , http://www.blue-bird.com/global-bus-market.aspx , http://www.blue-bird.com/specialty-buses.aspx , http://www.blue-bird.com/product-literature.aspx#.U_xVdHmSf6k , and http://www.blue-bird.com/global-product-literature.aspx .

In short, very much agreed, roll-over protection is critically important.


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15. Designed for Redundancy, not Self-Repair-ability.


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Design for utmost practicality/survivability/self-repair-ability first!

You mentioned road-service/aid - you are building the rig to go places. Mostly no road-service available there!

Self-repair-ability is not only good for the owner/driver, but any help they might encounter out there, will appreciate also, if they don't need a specialist education to ....help out!

Regarding self-repair-ability, I have already stated my point of view, as inspired by egn's thoughts about how the days of self-repairability are probably over. You can keep repeating that the vehicle should be self-repairable, and I will keep repeating that it probably will not be, especially if it has a serial hybrid drive-train. So probably best to call this issue closed, and here too, we should agree to disagree?

Following egn's as well as Haf-E's suggestions, I will be designing for redundancy, not self-repairablity. If that does not interest you, or if you think it's a wrong-headed or misguided design objective, no worries. But I will still be going in that direction all the same......

Here is the exchange with egn, much earlier in the thread, that set the groundwork for this overall design direction:

Glad you brought up hybrid and electric, egn.

In previous posts you've been dead-set against electrics for the chassis and engine. Your central concern has been ease of repair/maintenance in remote corners of the globe, where suitable mechanics or diagnostic equipment will not be available. So why would you propose hybrid or electric for such a vehicle? Even militaries that are well-funded and have internal, "in house" mechanics, are now deliberately buying mechanically and electrically simplified vehicles so that they don't have headaches in the field. I remember reading somewhere that military-spec G-wagens don't have electric windows, for exactly this reason. So why would you propose that an expedition vehicle like this should have an electric engine (or engines, plural...)?

So why would you propose that an expedition vehicle like this should have an electric engine (or engines, plural...)?

The answer is pretty easy:

With a hybrid/electric propulsion you can build in redundancy easily. i.e. you can spend every axle an extra motor, have multiple smaller engine/generator units, multiple battery modules, ... So the availability of such a drive-train could be much higher than with only one large engine and transmission.

Implementation can be a serial hybrid, but may be also be other types of hybrids like direct propulsion of one or more axles mechanical and the other axles electrical. The engines/generator modules may be replaced by fuel-cell modules later to push fuel-efficiency further.

Full electric trucks have been already build like E-Force.

Siemens even build hybrid vehicles for the eHighway.

Of course, this all is currently to expensive for general commercial use, but private expedition truck owners may not look at how economic such a solution is, but more if it is something exclusive with special capabilities. The most expensive part will currently be the battery modules. But the price may come down considerably in the future.

The advantage of an integrated solutions also that it can be optimized aero-dynamically very well, without to many compromises on aesthetics. Our integrated Concorde camper had a fuel consumption of about 14 l/100km, the same sized bed over cab camper version used 16+ l/100km.

Full electric buses used for regular line service use less than 1 kWh/km. . At highway speed such a vehicle will use about 1-2 kWh/km.

1 kWh storage currently costs about 500 US$/400 €. So to have a range of 100 km electric, you need 100-200 kWh of battery storage with prices ranging from about 50.000 US$/40.000€ to 100.000 US$/80.000€. I think an hybrid-electric propulsion should be possible for material costs of about 200.000 - 300.000 US$. You can save much with a lower range, but then you have to look whether the battery can support the necessary discharge rate.

As was already written, such a concept is also ideal to have an all-electric household and use only one fuel type in the vehicle. Solar power all over the vehicle with a few kWp can fuel the household and in emergency the car itself at least for a few km a day.

So if I would win a lottery and have then the money to spend, I would certainly look into such a concept. :wings:

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Or perhaps the TOAD should be a G-wagen configured with a much lower pop-up camper, like the XP Camper -- see post #152 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page16 ?

Or perhaps the TOAD should be a G-wagen equipped with ORC's Camper Pro: see http://www.orc.de , http://www.orc.de/inhalt.php?bereich=Reisemobile&subnav=50&sprache=2 , http://www.orc.de/produkte/download/Catalogue_GCampPro201108.pdf , http://www.orc.de/inhalt.php?bereich=Reisemobile&subnav=50&sprache=1 , http://www.orc.de/produkte/download/Katalog_GCampPro_201108.pdf , http://www.orc.de/inhalt.php?bereich=Zubeh%F6r&subnav=13&sprache=2 , http://www.orc.de/produkte/download/Catalogue_MercedesGPur_de_eng_201403.pdf , http://www.orc.de/inhalt.php?bereich=Zubeh%F6r&subnav=13&sprache=1 , http://www.orc.de/produkte/download/Katalog_MercedesGPur_de_eng_201403.pdf , http://www.orc.de/produkte/download/catalogue_gpur_201104.pdf , http://www.mercedes-fans.de/inside/inside_artikel/id=3451 , http://www.mercedes-fans.de/galerie/id=1547 , http://www.mercedes-fans.de/picture/picture=48078 , http://www.adventuremedia4u.de/4x4fahrzeuge/fernreisemobile/orc-mercedes-g-camppro.html , and http://www.fourbyfourclub.com (I gave the links in both English and German, and direct links to the PDFs, because the ORC website is very badly organized, and the English PDF links sometimes do not work....)

Here are some videos:


[video=youtube;_snqzACvkIY]https://www.youtube.com/watch?v=_snqzACvkIY [/video]

Or perhaps the TOAD should be a G-wagen very well-equipped for expedition travel, but only with a Pop-Up tent, as per the G-wagen "Entdecker" put together by UniCat. See http://www.mercedes-g-entdecker.com , http://www.mercedes-g-entdecker.com/images_shen/pdf/ENTDECKER_en.pdf , , http://www.mercedes-g-entdecker.com/photo.html , http://expeditionportal.com/gelaendewagen-entdecker/ :


[video=youtube;gQfFO51TJh4]https://www.youtube.com/watch?v=gQfFO51TJh4* [/video]

What do you think? My own inclination is to go with a TOAD that has a hard-shell camper, or almost completely hard shell, like the Azalai, as opposed to just an RTT, as per the Entdecker. Because this TOAD should have the same climate capabilities as the main vehicle., and an RTT will simply not work in Siberia. Whereas the Azalai has long since been Sahara-tested, Tibet- and Himalaya-tested, and Siberia-tested.

I wonder what the maximum allowable size is for a TOAD, in various countries?

egn, if you are reading this, do you know what the maximum allowable size would be in Germany, for a vehicle towed by a motorhome?

So if the main "base camp" vehicle is really not intended for expeditions up creek beds, then I see no reason why it could not be proportioned more like a Newell or Concorde motorhome, approaching 3.95 m in height. But of course, this main vehicle still needs to be "bad-road" capable. It still needs to be able to drive Australia's corrugated tracks, like Mañana, or the G219 highway in Tibet. Which, I think we can agree, a Newell or a Concorde would not be able to do, without busting an axle or two.


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Definately illegal in the UK.
Not sure on the rest of the EU,but i'd imagine you'd be pushing your luck, you are definately getting into requiring a commercial truck licence territory.


Top Speed.
Bear in mind the legal speed limit for the EU for commercial heavy goods trucks is 90kph/ 56mph,and they HAVE to be speed limited to this.
Now 'camper' and ' motorhome' are not commercial vehicles, and have been exempt from this,but, ( you knew there had to be a 'but' coming) .... There is talk of this changing to any vehicle with a gross weight over 7.5t.
The optimum fuel economy on my 18t works truck is at 50mph on cruise control, on a dual carriageway.

Height.
My personal view is that you need to bear in mind actually driving a tall vehicle,especially in blustery conditions, if you've ever been in a 'high sider' in strong cross winds, it can be, how shall i put it, interesting! ( even fully loaded wagons get blown across motorway lanes....)
Again driving into a headwind will have a massive influence on your fuel economy.


Length of the vehicle is not so much an issue,once you are used to driving it.
But you need to watch the rear overhang on the vehicle,thats the length of the body from the rear wheels to the rearmost of the vehicle.
You really dont want a big overhang. Tight turns can be a nightmare,even with rear wheeel steer.

 

[biotect]

,,
CONTINUED FROM PREVIOUS POST #755

*********************************************


16. This is an Exercise in Transportation Design, not Automotive Engineering


*********************************************


Last but not least, thjakits, I feel the need to respond with some degree of argumentative force, to your closing thoughts about design methodology:

YES - go for it!! BUT you WILL HAVE TO get involved in the technical design part too - just concentrating on the living quarters, visual art and trying to integrate social ideas about 2nd/3rd/4th world compatibility will never lead to anything near what you list above!

Your list still describes a fairly capable, serious machine - some of your artistic/social desires though will not fit into it.

If you are serious about the Terraliner, you will have to design on the very edge of everything!!

You want a vehicle that is built by the hundreds or even thousands - it HAS to appeal to a rather wide audience!

**************************************

Go step by step:

a) What is the most extreme (driving, remote areas, stay on site) group you want to address - serial production already eliminates most of the unique-expedition-ride folks

b) Design for utmost practicality/survivability/self-repair-ability first! Aesthetics ("Art/Beauty") is the VERY last you should be concerned with!

Please remember, I am a transportation designer, not an automotive engineer.

You could try next arguing that I am in the wrong profession. But clearly, that's not going to change, either.....:sombrero:

Although most participants on ExPo seem to have technical backgrounds, or backgrounds in science and engineering, and although they seem to prefer technical discussions to the exclusion of aesthetic, social, or ethical ones, modern transportation design studies is not like this at all. This may be hard for some ExPo participants to hear, or accept. But it's a simple fact. A consideration of economic, political, environmental, and ethical questions is now absolutely central to the Transportation Design profession. And it is centrally important to Transportation Design studies, especially at the MFA level. Why else do you think I developed and posted all that material about the emerging Asian Highway Network, or about the Williamson article, and the Ethics of expedition motorhome design? I am hoping to rework this material into an essay that I will be expected to write shortly, to meet an academic requirement, as part of an MFA program.

The following is the description of the MFA program at the Art Center College of Design in Pasadena, California, universally acknowledged as the foremost institution for Transportation Design studies in the United States:

Transportation Systems and Design

Our Transportation Systems and Design students are developing compelling, sustainable and viable transportation and mobility solutions for an inspired future.

For people passionate about the automotive industry and the expansive field of transportation and personal mobility, our Master of Science program encourages creativity and strategic thinking beyond the sketchpad to impact the vehicle manufacturing industry, and to create better, compelling transportation solutions at a systems level, rather than a product level.

Because design brings value well beyond the areas of product and service development, our curriculum encompasses a combination of design methodology, strategic innovation, systems thinking, customer-driven research, political insight plus entrepreneurial and communication skills. The program’s community of students—with prior degrees in subjects such as design, architecture, urban planning, business, engineering, anthropology and economics—brings diverse perspectives and stimulates the transdisciplinary culture that is essential to advance transportation design throughout the coming decades. Degree candidates participate in international conferences and conduct rigorous research; in collaborative teams they explore how to create the ideal user journey while preserving precious environmental resources. The College’s strong ties to government and industry provide direct access to organizations pushing the emerging fields of new mobility and alternative energies.

This course of study encourages graduates to become agents of change prepared to reinvigorate industry across a broad landscape, from design studios and manufacturers to organizations responsible for transportation systems solutions at the national, state and local levels.

See http://www.artcenter.edu/accd/programs/graduate/transportation_design.jsp .

I am not attending Art Center, I am attending an MFA program at an institution that is roughly equivalent in Britain. But the description could be the same.

So even if the typical ExPo participant is not interested in such questions, that does not mean that they are not worth asking, or that they should not be central to this thread. This thread, after all, is a "transportation design thread". Yes, it covers questions in expedition vehicle engineering, up to a point. But the concerns of this thread are not exhausted by expedition vehicle engineering.

Furthermore, as I already indicated to campo, in transportation design ethical concerns come first, not last. Perhaps ethical concerns come last (or not at all) from an engineering point of view, in which only instrumental rationality matters. But from my conversations with young engineers I've gathered that the engineering profession has changed greatly, too, over the last 50 years. For instance, courses in "ethics and engineering" are now mandatory at most topnotch Universities.

To make the issue here really simple: if something is unethical, then it is not worth designing or engineering in the first place. If it really is unethical, then it is positively unethical to design it. So that's why I had no choice but to really think through the Wiliamson article at great length, before proceeding much further.

campo seems to have recognized the importance of my having done so, which is why he revised his understanding of the design methodology for the TerraLiner as follows:

Hi Biotect and the others,

Thank you for your amazingly detailed remarks.
I did not think that you where that far in your concept evolution.
.
You're right and even if it is not a linear process I would keep in mind following and adapted maybe theoretical development structure:
.
Design planning:

1. Ethical, environmental and budgetary study
2. Overall idea and definition of main parameters (length, # persons, destinations)
3. Choice for today's most innovative techniques or futuristic and only designer solutions
4. Weight repartition and axle position
5. Hybrid propulsion and drive line components position
6. Monocoque design or traditional chassis and suspension choice
7. Garage or storage position for bikes, spare wheels and doors
8. Position of tanks, batteries and techniques
9. Interior layout
10. Exterior design
11. Building timeframe

Regards Campo

On my own view campo got the sequence right. Ethics, along with social, political, and environmental issues, should come first, not last.

So perhaps here too, thjakits, you and I will simply have to agree to disagree?

However with all that said, yes, I will need to spend considerable time working through the fundamental engineering of the chassis, before I revisit the aesthetic questions that are dearest to my heart. But I have already stated as much, very clearly and explicitly, in my reply to campo in posts #746, on the previous page at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page75 . I can state only two or three times times in this thread that I will be looking further into a tubular space-frame solution for the chassis, and that I will consult with friends who have strong backgrounds in automotive engineering. After that, further repetition becomes a bit ridiculous, don't you think?....

And finally, with all that said, I really do appreciate your feedback, thjakits. It is, quite literally, priceless. Inspired "devil's advocacy" should always be an important component of any design process. I created this thread, and I have encouraged such critical feedback, for a reason: because the design will prove all the stronger for it.

Before your posts, for instance, I had honestly not heard of hydro-drives as an alternative to all-wheel drive for large trucks, and I have been all over the MAN website. Sure, I knew about hydraulic motors, at a vague level. But I didn't know that since roughly 2005 MAN has been selling hydro-drives as a fuel-efficient alternative to all-wheel drive, for its large trucks. Remember, my prior background is really interior design and architecture, not automotive design. So just like a few other participants on this thread, I am facing a pretty steep learning curve, too.

So once again, many thanks.

All best wishes,



Biotect

 

[biotect]

..,

Definately illegal in the UK.
Not sure on the rest of the EU,but i'd imagine you'd be pushing your luck, you are definately getting into requiring a commercial truck licence territory.


Top Speed.
Bear in mind the legal speed limit for the EU for commercial heavy goods trucks is 90kph/ 56mph,and they HAVE to be speed limited to this.
Now 'camper' and ' motorhome' are not commercial vehicles, and have been exempt from this,but, ( you knew there had to be a 'but' coming) .... There is talk of this changing to any vehicle with a gross weight over 7.5t.
The optimum fuel economy on my 18t works truck is at 50mph on cruise control, on a dual carriageway.

Height.
My personal view is that you need to bear in mind actually driving a tall vehicle,especially in blustery conditions, if you've ever been in a 'high sider' in strong cross winds, it can be, how shall i put it, interesting! ( even fully loaded wagons get blown across motorway lanes....)
Again driving into a headwind will have a massive influence on your fuel economy.


Length of the vehicle is not so much an issue,once you are used to driving it.
But you need to watch the rear overhang on the vehicle,thats the length of the body from the rear wheels to the rearmost of the vehicle.
You really dont want a big overhang. Tight turns can be a nightmare,even with rear wheeel steer.

Hi optimusprime,

Sorry, I had to go around your post a bit. I needed to fit in pictures of the Kimberley T3 Caravan, in order to cement my point to thjakits that more curvilinear design is eminently possible in off-road products. That curvilinear design is both practical and desirable, and that off-road caravans and expedition motorhomes do not have to look like rectilinear boxes.

In response to your comments:

I more or less begin from the assumption that anyone driving the TerraLiner will want to have a commercial truck license under their belt. But are you saying that even with a commercial truck license, the owners of large motorhomes are not able to tow an additional trailer, or a car?

I am pretty certain that this is legal in Germany, otherwise Ketterer would not be making horse-trailer motorhomes that can tow an additional trailers:






See http://www.ketterer-trucks.de/en.html , http://www.ketterer-trucks.de/en/models/category/c/equestrian.html , and http://www.ketterer-trucks.de/en/models/category/c/equestrian/model/professional-trailer-2.html .

Thanks for the heads up about the speed limit in the UK for medium and heavy trucks. I would still like to hear from campo about why he proposed 140 kmh. On the continent drivers are a bit crazier. There are speed limits in Italy, for instance, but it seems that nobody respects them. The last time I drove on the autobahns in Germany, there were no speed limits for cars. I am not sure what the speed limit is for trucks or motorhomes on the autobahns in Germany.

As for height and side-winds, motorhome supply companies now make air-suspension systems that automatically compensate. See for instance "Active Air", made by HWH -- http://www.hwhcorp.com/activeaircontrol3.html , http://www.hwhcorp.com/ml35458.pdf , http://www.hwhcorp.com/ml45343.pdf , and http://www.hwhcorp.com/ml45344.pdf :







As for rear overhang, I have been designing the TerraLiner to have 45-degree approach and departure angles, front and back. In other words, virtually no overhang.

All best wishes,


Biotect

 

[optimusprime]

Hi optimusprime,

Sorry, I had to go around your post a bit. I needed to fit in pictures of the Kimberley T3 Caravan, in order to cement my point to thjakits that more curvilinear design is eminently possible in off-road products. That curvilinear design is both practical and desirable, and that off-road caravans and expedition motorhomes do not have to look like rectilinear boxes.

In response to your comment: I more or less begin from the assumption that anyone driving the TerraLiner will want to have a commercial truck license under their belt. But thanks for the heads up about the speed limit in the UK for medium and heavy trucks. I would still like to hear from campo about why he proposed 140 kmh. On the continent drivers are a bit crazier. There are speed limits in Italy, for instance, but it seems that nobody respects them. The last time I drove on the autobahns in Germany, there were no speed limits for cars. I am not sure what the speed limit is for trucks or motorhomes on the autobahns in Germany.

As for height and side-winds, motorhome supply companies now make air-suspension systems that automatically compensate. See for instance "Active Air", made by HWH -- http://www.hwhcorp.com/activeaircontrol3.html , http://www.hwhcorp.com/ml35458.pdf , http://www.hwhcorp.com/ml45343.pdf , and http://www.hwhcorp.com/ml45344.pdf :


View attachment 248867




As for rear overhang, I have been designing the TerraLiner to have 45-degree approach and departure angles, front and back. In other words, virtually no overhang.

All best wishes,


Biotect

Hi Biotect

It is a mandatory 90kph throughout the EU for trucks.

 

[biotect]

Thanks for that, optimusprime.

Again, would be good to hear from campo why he proposed 140 kmh. What do you think of the HWH "Active Air" solution?

All best wishes,


Biotect

 

[optimusprime]

,,
CONTINUED FROM PREVIOUS POST #755

*********************************************


13. This is an Exercise in Transportation Design, not Automotive Engineering


*********************************************


Last but not least, I feel the need to respond with some degree of argumentative force, to your closing thoughts about design methodology:





Please remember, I am a transportation designer, not an automotive engineer.

You could try next arguing that I am in the wrong profession. But clearly, that's not going to change, either.....:sombrero:

Although most participants on ExPo seem to have technical backgrounds, or backgrounds in science and engineering, and although they seem to prefer technical discussions to the exclusion of aesthetic, social, or ethical ones, modern transportation design studies is not like this at all. This may be hard for some ExPo participants to hear, or accept. But it's a simple fact. A consideration of economic, political, environmental, and ethical questions is now absolutely central to the Transportation Design profession. And it is centrally important to Transportation Design studies, especially at the MFA level. Why else do you think I developed and posted all that material about the emerging Asian Highway Network, or about the Williamson article, and the Ethics of expedition motorhome design? I am hoping to rework this material into an essay that I will be expected to write shortly, to meet an academic requirement, as part of an MFA program.

The following is the description of the MFA program at the Art Center College of Design in Pasadena, California, universally acknowledged as the foremost institution for Transportation Design studies in the United States:



See http://www.artcenter.edu/accd/programs/graduate/transportation_design.jsp .

I am not attending Art Center, I am attending an MFA program at an institution that is roughly equivalent in Britain. But the description could be the same.

So even if the typical ExPo participant is not interested in such questions, that does not mean that they are not worth asking, or that they should not be central to this thread. This thread, after all, is a "transportation design thread". Yes, it covers questions in expedition vehicle engineering, up to a point. But the concerns of this thread are not exhausted by expedition vehicle engineering.

Furthermore, as I already indicated to campo, in transportation design ethical concerns come first, not last. Perhaps ethical concerns come last (or not at all) from an engineering point of view, in which only instrumental rationality matters. But from my conversations with young engineers I've gathered that the engineering profession has changed greatly, too, over the last 50 years. For instance, courses in "ethics and engineering" are now mandatory in all topnotch university programs.

To make the issue here really simple: if something is unethical, then it is not worth designing or engineering in the first place. If it really is unethical, then it is positively unethical to design it. So that's why I had no choice but to really think through the Wiliamson article at great length, before proceeding much further.

campo seems to have recognized the importance of my having done so, which is why he revised his understanding of design methodology as follows:




Sorry, but on my own view campo got the sequence right. Ethics, along with social, political, and environmental issues, should come first, not last.

So here too, perhaps you and I will simply have to agree to disagree?

However with all that said, yes, I will need to spend considerable time working through the fundamental engineering of the chassis, before I revisit the aesthetic questions that are dearest to my heart. But I have already stated as much, very clearly and explicitly, in my reply to campo in posts #746, on the previous page at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page75 . I can state only two or three times times in this thread that I will be looking further into a tubular space-frame solution for the chassis, and that I will consult with friends who have strong backgrounds in automotive engineering. After that, further repetition becomes a bit ridiculous, don't you think?....

And finally, with all that said, I really do appreciate your feedback, thjakits. It is, quite literally, priceless. Inspired "devil's advocacy" should always be an important component of any design process. I created this thread, and I have encouraged such critical feedback, for a reason: because the design will prove all the stronger for it.

So once again, many thanks.

All best wishes,



Biotect

I agree with both issues raised here.
I dont think you can have engineering without design and vice versa, both are equally important.
For instance, there is no point in designing something visually stunning, only for the engineers to say ,nope,not possible.
As much as there is no point building something,that engineering wise is presicion personified,but is so unattractive to look at,nobody would be willing to own it.

As this would be a 'lifestyle' purchase, the normal rules of a car purchase ( economy,resale,performance,servicing etc etc) although important,and needing to be thought through,it needs to appeal to both head and heart.

 

[optimusprime]

..,



Hi optimusprime,

Sorry, I had to go around your post a bit. I needed to fit in pictures of the Kimberley T3 Caravan, in order to cement my point to thjakits that more curvilinear design is eminently possible in off-road products. That curvilinear design is both practical and desirable, and that off-road caravans and expedition motorhomes do not have to look like rectilinear boxes.

In response to your comments:

I more or less begin from the assumption that anyone driving the TerraLiner will want to have a commercial truck license under their belt. But are you saying that even with a commercial truck license, the owners of large motorhomes are not able to tow an additional trailer, or a car?

I am pretty certain that this is legal in Germany, otherwise Ketterer would not be making horse-trailer motorhomes that can tow an additional trailers:


View attachment 248868 View attachment 248869 View attachment 248870
View attachment 248871 View attachment 248872 View attachment 248873


See http://www.ketterer-trucks.de/en.html , http://www.ketterer-trucks.de/en/models/category/c/equestrian.html , and http://www.ketterer-trucks.de/en/models/category/c/equestrian/model/professional-trailer-2.html .


All best wishes,


Biotect

Ahh there you have it, the wording there is important.
Trailer
In the UK towing a vehicle does not make it a trailer!
There are all sorts of rules and regulations.
I would assume the EU would have rules as well.

 

[optimusprime]

Thanks for that, optimusprime.

Again, would be good to hear from campo why he proposed 140 kmh. What do you think of the HWH "Active Air" solution?

All best wishes,


Biotect

It looks promising,esp if you can drop the ride height down when on good rds to lower the centre of gravity,but how quick could it respond to sudden situations would be the key question.
As well as being able to alter ride height for differing terrain, you could get really creative,and lift the middle axle up for travelling on paved roads,thus saving tyre wear.......

 

[biotect]

Ahh there you have it, the wording there is important.
Trailer
In the UK towing a vehicle does not make it a trailer!
There are all sorts of rules and regulations.
I would assume the EU would have rules as well.

Hi optimusprime,

I simply assumed that because "TOADS" are so common in the United States, and because Mañana pulled a TOAD in Australia, that towing a vehicle behind one's motorhome would be OK in Europe and the UK as well.

Are you dead certain that you have your facts straight? I just looked up "towing a car with a motorhome", and immediately came across the following webpage on the "Camping and Caravanning Club of the UK" website, a reliable source of information: http://www.campingandcaravanningclu...technicalhelp/towing/towing-with-a-motorhome/ . According to this webpage, it's really no problem at all to tow a car behind a motorhome in the UK. Sure, you need the necessary license to do it. But it does not seem to be illegal, as you just claimed.

Here is an image from the webpage, which says it all:





If you read the fine print on this webpage, you will see that the law seems to be ambiguous. But ambiguous is not the same thing as illegal.

Many Brits do in fact tow their vehicles with A-frames, and the current interpretation of the law runs that a car towed with an A-frame attached is considered a trailer. Only braking and lighting requirements have to be met. Driving in Europe with such an arrangement, however, seems to be a bit more complicated. The general rule is that if driving with a certain arrangement is legal in your home country, then as a visitor you are entitled to do the same in any other EU country. But if you run into a difficult police officer, he or she may demand that you to decouple your car anyway, forcing you and your partner to drive motorhome and car separately. Apparently this has happened to a few Brits towing their cars with their motorhomes in Spain.

All best wishes,


Biotect

 

[campo]

Sorry that i did not yet answer your 140km/h question.
I was making some nice pictures for you in Hannover yesterday.

 

[optimusprime]

Hi optimusprime,

I simply assumed that because "TOADS" are so common in the United States, and because Mañana pulled a TOAD in Australia, that towing a vehicle behind one's motorhome would be OK in Europe and the UK as well.

Are you dead certain that you have your facts straight? I just looked up "towing a car with a motorhome", and immediately came across the following webpage on the "Camping and Caravanning Club of the UK" website, a reliable source of information: http://www.campingandcaravanningclu...technicalhelp/towing/towing-with-a-motorhome/ . According to this webpage, it's really no problem at all to tow a car behind a motorhome in the UK. Sure, you need the necessary license to do it. But it does not seem to be illegal, as you just claimed.

Here is an image from the webpage, which says it all:


View attachment 248898


If you read the fine print on this webpage, you will see that the law seems to be ambiguous. But ambiguous is not the same thing as illegal.

Many Brits do in fact tow their vehicles with A-frames, and the current interpretation of the law runs that a car towed with an A-frame attached is considered a trailer. Only braking and lighting requirements have to be met. Driving in Europe with such an arrangement, however, seems to be a bit more complicated. The general rule is that if driving with a certain arrangement is legal in your home country, then as a visitor you are entitled to do the same in any other EU country. But if you run into a difficult police officer, he or she may demand that you to decouple your car anyway, forcing you and your partner to drive motorhome and car separately. Apparently this has happened to a few Brits towing their cars with their motorhomes in Spain.

All best wishes,


Biotect

I should have reworded my earlier replies better.
I meant that towing a 4x4 type vehicle (as that was the subject you put forward) would be frowned upon,its all to do with gross weights,and how the various enforcing bodies interpret that.

As you righly state,it is ok to tow a small car,provided it is fitted with a braking system.
However i do agree with you it is a grey area,and is sometimes very contentious.
So err on the side of caution,and don't tow a larger vehicle!

Regards

 

[campo]

My ideas about the tires and the 140 km/h.
.
The 14R20 Michelin XZL are limited by their speed index on 90km/h.
Just forget about them for innovative projects before the start to think.
The some smaller MPT 365/80R20 XZL can do 110 km/h
This speed index is also coupled to the weight per wheel and the inflation pressure.
You will see these 14R20 max 90km/h doing 150 km/h in the Dakar race trucks but they only have 8 to 9 metric ton load (divided by 4 wheels)
.
14R20 (and 16R20) in profile type Michelin XZL are extreme high tires and that is very good for ground clearance and off road.
For the rest (that means 99% of the time) like EGN mentioned with his words, they are not funny to drive.
.
All modern traveller expedition truck tires wil have more low profile like 385/55R22,5 in the mixed on/off road profile like Michelin XZY3.
The lower the profile the more modern they are.
.
Continental will have 3 new 22,5 profiles in 2015 as just announced on the right side of this picture.
.

.

For the “terraliner” innovation concept truck would not advise old 14R20 dimensions but modern /55 or /50 tires.
When missing some tire height for your off-road travel do something with the ground clearance of the axle and suspension but keep using low profile tires.
.

I was not mentioning 140km/h for driving at that speed.
My truck has theoretical topspeed of 147 km/h and other new ones today have only 125 or 135 km/h depending of the configuration but with identical trucks.
Mine is now the most economical.
We did some fuel comparisons: 10% less than one and almost 20% less than another one driving behind each other on a long highway traject at 90km/h average.

In practice or theory you can drive up to maximum 110 km/h on some road decks.
Maximum I ever did to test was 130 km/h but impossible to keep the truck on the road at that speeds.
Normal cruise is from 89 to 96 or 104 depending from where I drive.
That is lots faster than the other trucks !

Legally is 80 km/h in Germany/Austria and many others (everybody drives 89 on the limiter
Belgium/Spain is 90 km/h (everybody drives 91 km/h)
If you get caught over speeding you can lose your driving licence !
In France classified as RV and under 12 tons (I am at 11.990 kg) is admitted 110 km/h !
But that is to fast to drive with the XZL tires and gives lots of stress to the driver.
.
Green zone driving.
I had some professional driving training to reduce fuel consumption.
Many faults are made in designing axle configuration.
We are driving with travel vehicles and not a winterdienst salt spray vehicle.
I have seen trucks where the top speed was 80km/h beginning red zone and 90km/h end red zone.
That are old fashion ex-military vehicles NOT build for today travellers.
My theoretical top speed is 147 km/h at 2500 rpm (do not compare it with a 2300 or even 2100 max rpm engine !)
I drive 90 km/h at 1500 rpm. That is where the green zone starts.
There you get the lowest fuel consumption. Proven !
With 12 gears and 290Hp you never have traction problems on the road with only 10.500kg.
.
This is a almost world record picture for the ones who do understand it.
Average speed was 89 km/h
Tires XZL at 5.5 bar
Weight 10.500 kg filled
Average fuel consumption only 19,1 l/100 km over 900 km distance
.

.
.

So Biotect for your innovative 6x6 concept please do only mention tire and speed axle reduction solutions that are as good or better than the one I already have today.

.

Regards Campo

PS We have to insert a paragraph about homologation in the work list from above.