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

[biotect]

Hi dwh,

If you look at the flimsy "concept designs" like the "Troy" and "Nimbus" by Galvani referenced earlier, or the OEX-B by Bekradi that we now all know well, they posit one electric hub motor per wheel. More generally, in transportation design these days almost everyone who is interested in hybrid and electric vehicles seems obsessed with hub motors. So perhaps it was my fault. I sort of "picked up" the enthusiasm, and simply assumed that an overlanding expedition vehicle that was a serial hybrid would have hub motors, too.

But it was a stupid assumption, for the reasons made very clear by Haf-E. In an overlanding expedition vehicle, one does not want the electric motors near the wheels. And one wants them well-protected from shock. Wheels have one role to play, motors another, and the idea of fusing the two functions in a single location only makes sense on excellent, paved roads, of the kind used by hybrid European city buses, electric sports cars, and electric race cars.

So blame me; it's my fault for stipulating hub motors prematurely......:drool:

One drive e-motor per axle now seems agreed upon by all, with the three e-motors up and away, well protected from submersion in water and muck. Remember, the TerraLiner is also supposed to have excellent, MAN-KAT level fording abilities (up to 1.5 m), and that only becomes genuinely possible if the electrics are well-protected from water -- see posts #511 and #512 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page52 :





For the record, the idea of hybrid technology used in a "watery" context is not impossible, and in fact has already been implemented. Here the earlier research regarding the amphibious hybrid bus made by DATV proves valuable. Even though the "Floating Dutchman" can swim like a boat, it's a hybrid vehicle -- see http://www.datbv.com/en/ and http://www.floatingdutchman.nl/en/about-the-bus/ :

Explore the Floating Dutchman

The Floating Dutchman amphibious bus is the only hybrid amphibious touring car the world that complies with all European road and water regulations. The bus has been built by Dutch Amphibious Transport Vehicles (DATV) in Nijmegen. Three years ago DATV started the development of two prototype vehicles:
- The ‘010' has been specifically designed for the rough waters in the Port of Rotterdam and seats 43 people.
- The ‘020' has been specifically designed for the canals of Amsterdam. The ‘020' bus is a hybrid vehicle as it cruises down Amsterdam's canals using battery power. It seats 48 people and is low enough to clear the bridges of Amsterdam's canals.
The ‘010' has been bought by our partner in Rotterdam, Splashtours, and is operational since March10. For more information on Splashtours please visit their website.

TechnicalSpecificaties Floating Dutchman

Technical Specifications
Comfort: Kiel seating Water drive Electrical driven Water safety Watertight compartments
Toilet Block Voith air type VIP380 50 life jackets
50kW 5 emergency exits
Capacities 50 passengers Manoeuvring Bowtruster 10kW
( including driver & deckhand) Sterntruster 7.5kW Colour RAL colours
Batteries 190 Lithium ion
Technical Specifications Volvo engine
Vehicle dimensions Length 14.02metres
Width 2.55metres
Height 3.22metres
Wheelbase 6.8metres
Empty weight 21000kg
Draft when floating 1.8 metres Certification Class3 city bus
Dutch Marine Certification
For Amsterdam canal aria

Peformance Max Roadspeed : 80km/h
Max speed at sea: 3 knots Options Airco system
Entertainment system
Panoramic roofwindows Builder Dutch Amphibious Transport Vehicles/J.de Jong Scheepsservice
Nijmegen, The Netherlands
Propulsion Rear wheel drive Options Airco
Air suspension Entertainment system
Automatic limited slip differential Road safety Electric fly drive
Body cage roll over tested, ABS

And for lots of videos and more links, see posts #629 and #630, at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page63 .

All best wishes,



Biotect

 

[optimusprime]

Hi thjakits

I cannot think of any 'modern' commercial trucks with single rear axle and twin front steer axles for everyday useage.
Specialised vehicles such as the crane industry springs to mind.



Or alternatively, we could just forget all previous discussions and fit the running gear from this ......





http://youtu.be/3mr_pCrhTkk
Just for fun!

 

[biotect]

dwh,

Now, to add more fuel to the fire of this debate REOutShootinghunter), even in the one-E-motor-per-axle configuration, would you still advocate IS? Do think that even in this three-E-motor configuration, the right kind of IS could offer:

• a better, smoother ride overall?
• higher ground clearance along the center line of the vehicle, i.e. less junk in the center? Perhaps via "wishbone" IS?

As near as I can tell, that's how Oshkosh does it in the L-ATV. It uses TAK-4 Independent Suspension on all wheels, but they are driven by one E-motor per pair of wheels. But I could be wrong about this. I only have exterior pictures, and very poor schematics in the Oshkosh PDFs about "Propulse". What I really need (again), is a good schematic showing how Propulse works in concert with TAK-4. Again, see posts #671 and #672 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page68 :





The center-line ground clearance in these images seems very substantial, and it seems pretty obvious that this vehicle is using TAK-4 Independent Suspension.

All best wishes,


Biotect

 

[optimusprime]

Bio

Its not to much of an issue getting electric motors themselves wet.
Its not the water itself that does the damage,its all the stuff thats left when the water dries out thats the issue.
( although controllers and so on are a different matter)

I like driving through water,muddy water.
I always make a point of hosing the engine alternator through to wash out any mud left in there, as that is what kills it.

There is nothing to say that an electric motor fitted to a solid axle had to be fitted horizontally like a differencial would need to.
You can always have vertically,ie pointing upwards in the axle ( if that is the preferred drive solution) , keeping most of the motor out of harms way.

 

[optimusprime]

dwh,

Now, to add more fuel to the fire of this debate REOutShootinghunter), even in the one-E-motor-per-axle configuration, would you still advocate IS? Do think that even in this three-E-motor configuration, the right kind of IS could offer:

• a better, smoother ride overall?
• higher ground clearance along the center line of the vehicle, i.e. less junk in the center? Perhaps via "wishbone" IS?

As near as I can tell, that's how Oshkosh does it in the L-ATV. It uses TAK-4 Independent Suspension on all wheels, but they are driven by one E-motor per pair of wheels. But I could be wrong about this. I only have exterior pictures, and very poor schematics in the Oshkosh PDFs about "Propulse". What I really need (again), is a good schematic showing how Propulse works in concert with TAK-4. Again, see posts #671 and #672 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page68 :


View attachment 262792 View attachment 262793 View attachment 262794


The center-line ground clearance in these images seems very substantial, and it seems pretty obvious that this vehicle is using TAK-4 Independent Suspension.

All best wishes,


Biotect

You asked about a smoother ride.

That depends on a couple of things.
First springing method.
Are we talking leaf,coil,air or hydro whatever .... That makes a huge difference,no matter how they are fitted to the truck.
Then you need to take account of the weight of the vehicle, i drive an 18 ton truck,with leaf springs all round,beam axle up front,solid drive axle to rear.
The weight i'm carrying makes a huge difference to ride quality.
The heavier the load,the smoother the ride.

The type of suspension used makes no diffence ( on its own) to ride quality.
Spring rate is far more important.
Suspension That is designed to be able to handle a fully laden truck, is going less flexible and give a stiffer ride when the truck is unladen.

 

[biotect]

Bio

Its not to much of an issue getting electric motors themselves wet.
Its not the water itself that does the damage,its all the stuff thats left when the water dries out thats the issue.
( although controllers and so on are a different matter)

I like driving through water,muddy water.
I always make a point of hosing the engine alternator through to wash out any mud left in there, as that is what kills it.

There is nothing to say that an electric motor fitted to a solid axle had to be fitted horizontally like a differencial would need to.
You can always have vertically,ie pointing upwards in the axle ( if that is the preferred drive solution) , keeping most of the motor out of harms way.

Hi optimusprime,

Yes, I know. But when fording 1.5 m, we are talking about fully submersing electric hub motors. And in addition, there is the issue of corrugated roads. The Tanami Track breaks axles, so what do you think it might do to electric hub motors, mounted directly inside the wheels?




And see post #214 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page22 , for lots of videos of what bad-roads might be like, at least in Australia. The Tanami Track is not "off-road" driving, merely "bad road" driving, but I think it would wreck hub motors. I could be wrong about this. But it's interesting that Oshkosh does not use hub-motors in its hybrid diesel-electric L-ATV.

All best wishes,




Biotect

 

[optimusprime]

Hi optimusprime,

Yes, I know. But when fording 1.5 m, we are talking about fully submersing electric hub motors. And in addition, there is the issue of corrugated roads. The Tanami Track breaks axles, so what do you think it might do to electric hub motors, mounted directly inside the wheels?




And see post #214 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page22 , for lots of videos of what bad-roads might be like, at least in Australia. The Tanami Track is not "off-road" driving, merely "bad road" driving, but I think it would wreck hub motors. I could be wrong about this. But it's interesting that Oshkosh does not use hub-motors in its hybrid diesel-electric L-ATV.

All best wishes,




Biotect

I'm not advocating hub motors for the very reasons you've just said.
You notice i said electric motor fitted to an axle. That would eliminate the vibration that would happen with a direct wheel mount.

 

[biotect]

The difference regarding inter-axle distances between these commercial overlanding 4x4 trucks (Acacia Africa, Oasis, Odyssey), and the 6x6s posted above, is really quite striking.

This then makes me wonder:

(a) Do 4x4 commercial overlanding vehicles often turtle? Or are their breakover angles reasonably sufficient for the routes they run?

(b) If 4x4s do have a problem with turtling, then why do overlanding companies not use more 6x6's? Oasis and Dragoman both seem to have some 6x6's, but otherwise the 4x4 format seems far more common.


All best wishes,



Biotect

I doubt that it's a common problem.

That's a problem that you encounter off-road, but almost never on a road - even a bad road. When Stephen Stewart and Co. were doing road work in Tibet, they were breaking down the high center of the road to fill in the ruts so the other vehicles could make it through. The Mog had no problem. The ruts were created by bigger heavier (and almost certainly 2WD) trucks.

"When driving on roads like the N317 (as opposed to real off-road driving) the important thing is to have the same (or better) ground clearance as the most common vehicle (MCV) on the road (in this case the Dong Feng 7 Tonne truck). This is because any road hazard involving obstructions too big for the MCV will quickly get cleared by the MCV drivers."

http://www.xor.org.uk/travel/china2002/20021012.htm







Personally, I'd be more worried about A) sliding sideways off the trail or road, or B) getting stuck high-centered.

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1. Deep Ruts on Bad Roads


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Hi dwh,
Your post struck a chord very close to my heart, because it was about driving bad roads in Tibet.....:sunny: .... Where did you get these terrific images? The weblink doesn't provide them -- see http://www.xor.org.uk/travel/china2002/20021012.htm . I found one of them at http://www.xor.org.uk/silkroute/equipment/choosevan.htm , but the other?

And agreed, being able to clear the central mound of muck between the two ruts created by trucks is perhaps the most critical issue in bad-road travel:







Or being able to get past a bad patch when the bad-road becomes no road, and seems to literarily disappear, as happened to this couple traveling the G219 in Tibet; skip ahead to about 6:00 minutes into the video:




And see post #891 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page90 .


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[biotect]

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2. No longer worried about a 6x6 turtling


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However, with that said, I still suspect that "turtling" is a fairly common problem as well. Quoting NeverEnough from quite a while back:

All,

Here is a really great video of a wide range of trucks having fun: Magirus, MAN, Tatra, Unimog, IFA, etc.

Campo, about 2:35 into the video is a perfect example of what appears to be a Magirus truck "turtling". It has gotten stuck on the peak of a hill because its breakover angle was insufficient, i.e. because its inter-axle distance was too great:




Again, for breakover angle, see http://en.wikipedia.org/wiki/Breakover_angle . Has this ever happened to you in your 4x4? Do you know of anyone to whom it has happened? For me, this seems to be one of the strongest arguments in favor of a 6x6, because with three axles instead of two, the inter-axle distance could be minimized for a vehicle 9.5 or 10 m long.

All best wishes,


Biotect

Yes, [I have turtled] in a jeep, truck, atv and even motorcycle, but not in my RV. There's something "impractical" about putting several hundred K at risk trying to get to a campsite! So I'm just not too concerned with center lift or a lot of other stuff, because I just want my slide-outs (not mention doors and windows) to work after bouncing down rough roads for hundreds of miles- which is much more difficult than it might sound.

So what is my argument for IS? It's faster over rough roads, and time is valuable. Being able to travel just a little faster without inflicting unwanted (and expensive) wear and tear on a trick camper can add a lot of value to the journey. My rig does great on washboard at high speed because of the huge wheels. It would do even better with a mongo IS. And I'd pick up a few more miles per hour on the ruts and cobble, which is what really slows you down. Sure, there are occasional tricky spots that require good angles and strong construction, but I take it slow and I'm not afraid to back up, turn around, and find another way. As for 6x6, I like the idea for the redundancy, floatation, traction, even for the angles to get in and out of a wash or stream ford. But I'd like it a lot more if one pair could lift for the inevitable 90% of travel on paved roads (meaning a rig light enough to be well within spec on just 4 wheels).

Most overlanding companies are not very candid in their visual documentation. But West Africa Overlanding is, especially on its Facebook website, where it posts abundant images of "Aminah" (the truck's name) coming very close to turtling:






See www.overlandingwestafrica.com/thetruck/ , http://www.overlandingwestafrica.com/aminah-a-brief-history/ , http://www.overlandingwestafrica.com , http://www.overlandingwestafrica.com/videos/ , http://www.overlandingwestafrica.com/accratofreetown/ , http://www.overlandingwestafrica.com/trip-2/ , http://overlandingwestafrica.blogspot.com/2013/10/aminah-arrives-in-dakar-with-al-and-nev.html , https://www.facebook.com/pages/Overlanding-West-Africa/138402216190609?sk=wall&filter=12 , https://www.facebook.com/pages/Overlanding-West-Africa/138402216190609?sk=photos_stream , https://www.facebook.com/pages/Overlanding-West-Africa/138402216190609?sk=videos , and https://www.youtube.com/user/OverlandingWAfrica , and see posts #981, #982, and #987 to #989 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page99 .

But as I said, now that I've seen all those images of commercial 4x4 overlanding vehicles with huge inter-axle distances and terrible breakover angles, I am much less worried about turtling as a problem for a 6x6 TerraLiner.

See posts #1068 to #1080 for a "visual" account of why turtling in a 6x6 no longer worries me very much, at http://www.expeditionportal.com/for...edition-RV-w-Rigid-Torsion-Free-Frame/page107 and http://www.expeditionportal.com/for...edition-RV-w-Rigid-Torsion-Free-Frame/page108 .


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3. Center-Line Clearance, SA, IS, and TAK-4 Specifically


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So we can focus instead on the question of centerline clearance, and whether Independent Suspension as per TAK-4 really could provide better centerline clearance than Single Axle.

These images of Oshkosh's hybrid diesel-electric L-ATV tested in Baja 1000, suggest that it could (see posts #671 and #672, at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page68 ):






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Or perhaps Independent Suspension as you've suggested, dwh: a wishbone design easily accessible from the sides when the wheels are pulled off, and hence not cluttering up the center:

....in the serial hybrid scenario perhaps IS might make sense because it might allow a long, uninterrupted space in the center of the truck. But even in IS, the links in the suspension function better when long, so one probably won't gain that much uninterrupted space in the center of the vehicle in any case. Sounds like a good enough argument to me.....:ylsmoke:

But, as I was pointing out - those long links don't necessarily have to be side-to-side, they can be fore-and-aft. So you could have the IS, and the extra travel, without the stuff cluttering up the center underneath the vehicle.

That makes sense if using a one drive per hub setup. Another thing, is that - like the GMC Eleganza - the suspension (and drives) would be easily accessible from the side - just pull off the wheels and there it is.

Agreed, but interesting that this does not seem to be the TAK-4 IS design:


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I wonder why? I wonder why for its larger trucks like the HEMMT and the MTVR, or its civilian suspension for Fire-trucks, Oshkosh did not develop a "wishbone" version of TAK-4? Or perhaps the whole point of TAK-4, is that it is not a wishbone design?

Also notice that the military versus the civilian (fire-fighting) versions of TAK-4 do seem substantially different, at least as regards ground clearance. In the military pdf, there even seem to be two military versions of TAK-4, one with better center-line ground clearance that the other:





See https://oshkoshdefense.com/technology-1/advanced-suspension-technology/ , http://oshkoshdefense.com/components/tak-4/ , http://oshkoshdefense.com/wp-content/uploads/2014/09/OshDef_TAK4_FamBrch_SnglPgs_LowRes.pdf , http://www.army-guide.com/eng/product3871.html , http://oshkoshdefense.com/wp-content/uploads/2013/08/HMMWV_TAK4_SS_6-13-11.pdf , http://oshkoshdefense.com/wp-content/uploads/2013/08/Technology_Bro_12-13-2010.pdf , http://www.oshkoshdefense.co.uk/wp-content/uploads/2014/01/EN-UK_Technology_Bro_6-3-2011.pdf , http://www.autofieldguide.com/blog/post/oskosh-this-is-a-truck-bgosh , http://www.defencetalk.com/oshkosh-...elligent-independent-suspension-system-37434/ , http://www.defencetalk.com/oshkosh-...ion-system-enhances-hmmwv-capabilities-29030/ , http://www.team-bhp.com/forum/4x4-t...t-front-suspension-ifs-good-offroading-9.html , http://www.casr.ca/mp-armour-tapv-interim-rg31.htm , http://www.hybrid-vehicle.org/hybrid-truck-hemtt.html , https://oshkoshdefense.com/vehicles/hemtt-a3-diesel-electric/ , and http://oshkoshdefense.com/wp-content/uploads/2013/08/HEMTT_A3_SS_6-13-11.pdf ; and see post #853 at http://www.expeditionportal.com/for...pedition-RV-w-Rigid-Torsion-Free-Frame/page86 for more videos.

Oshkosh uses the TAK-4 system across its entire product range, from the smallest 4x4s to the largest 10x10 trucks. It also uses the TAK-4 suspension system in its "Striker" ARFF (Aircraft Rescue and Fire Fighting) vehicles, and its "Pierce" line of firetrucks -- see http://www.dieselpowermag.com/featu...r_oshkosh_striker/photo_07.html#__federated=1 , http://www.oshkoshairport.com/Oshko...PDF Documents/ARFF Trucks/Striker3000_6x6.PDF , http://w ww.team-eagle.ca/wp-content/uploads/2011/06/Oshkosh_Striker3000.pdf, http://piercemfg.com/en/experience/the-difference/product-technology/tak-4.aspx , http://www.piercemfg.com/PierceMfg/...nloads/Literature/PDFs/TAK-4-IFS-Brochure.pdf , http://www.piercemfg.com/PierceMfg/...e/Product Technology/TAK-4/TAK4_final-(1).pdf , and http://piercemfg.com/PierceMfg/medi...echnology/TAK-4/Pierce_TAK-4_Lipski_story.pdf .


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4. TAK-4 Videos


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Here I have focused largely on M-ATV videos, with two L-ATV videos at the beginning, and a few HUMVEE videos as the end, because videos that show how TAK-4 works in larger trucks, like the MTVR or the HEMMT, seem very hard to find. These videos provide lots of visual information about how TAK-4 actually "looks" and operates in a variety of conditions; also see https://www.youtube.com/playlist?list=PLkTfesItveXPbJjhpUjXNrL8hgClsPZLn and https://www.youtube.com/playlist?list=PLF2TqvTLfAJhHyeevAjnG7hE1Peorn-16 :


[video=youtube;gDbJhQHfW0Q]https://www.youtube.com/watch?v=gDbJhQHfW0Q&index=36&list=PLF2TqvTLfAJhHye evAjnG7hE1Peorn-16[/video]
[video=youtube;uHl8FnKOqb0]https://www.youtube.com/watch?v=uHl8FnKOqb0 [/video]



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[video=youtube;ovHp_Xa7hdE]https://www.youtube.com/watch?v=ovHp_Xa7hdE&index=6&list=PLkTfesItveXPbJjh pUjXNrL8hgClsPZLn[/video] [video=youtube;oX5uB_jVTls]https://www.youtube.com/watch?v=oX5uB_jVTls&index=10&list=PLkTfesItveXPbJj hpUjXNrL8hgClsPZLn[/video]
[video=youtube;BBl4vEHeBm8]https://www.youtube.com/watch?v=BBl4vEHeBm8&index=13&list=PLkTfesItveXPbJj hpUjXNrL8hgClsPZLn[/video]

For the same reason, the images that immediately follow below are screen-captures taken from the above videos. They suggest what a really good, capable Independent Suspension might actually look like. "Still" photos found on-line of the M-ATV and L-ATV are usually not action-shots, and they do not really demonstrate how the suspension works (or doesn't). Whereas the following screen-captures should demonstrate this a bit more. When looking at these images, always keep in mind that the M-ATV is actually quite a large, heavy truck, roughly 25,000 pounds.

I decided not to edit the superfluous bits at the top and bottom, so that it remains crystal clear that all of these shots are screen-captures of moving-image videos.


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5. A Visual Analysis of TAK-4 in the M-ATV


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Does the Oshkosh M-ATV with TAK-4 have more center-line ground clearance than Straight Axle? Perhaps not. But it certainly does not seem to have any less clearance.

These first shots are frontal images of the M-ATV, which should give some idea of what the TAK-4 suspension system looks like, when installed. They are "neutral" images, images without the “bounce” that might exaggerate the suspension clearance:









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These next images show the M-ATV with quite a bit more “bounce”:





And here are some side-shots:





These are shots of the M-ATV turning:





And these are images from underneath, which show how close the ground the center-line of the vehicle drops in response to a bump, or after a “bounce”:





These last two are perhaps the most telling images of the bunch, potentially damning in both directions, depending on whether you are an IS advocate, or SA advocate. In a solid axle this would of course never happen. The center of a solid axle cannot “droop” closer to the ground than the wheel centers to absorb a bump, because it is solid and straight. Whereas Independent Suspension does precisely this, thereby giving it the capacity to better absorb bumps at high speed. With IS, the entire mass of the vehicle is not catapulted into the air by the bump hit at high speed.

But according to Haf-E, thjakits, and others, coil + air suspension will have virtually the same ability to absorb bumps, just not at high speed, off-road. And driving at high speed off-road is not a TerraLiner design requirement.

Even so, NeverEnough suggested that being able to go just a little bit faster over bad roads (not off-road) would be a good thing, and that’s why he favors IS:

So what is my argument for IS? It's faster over rough roads, and time is valuable. Being able to travel just a little faster without inflicting unwanted (and expensive) wear and tear on a trick camper can add a lot of value to the journey. My rig does great on washboard at high speed because of the huge wheels. It would do even better with a mongo IS. And I'd pick up a few more miles per hour on the ruts and cobble, which is what really slows you down. Sure, there are occasional tricky spots that require good angles and strong construction, but I take it slow and I'm not afraid to back up, turn around, and find another way. As for 6x6, I like the idea for the redundancy, floatation, traction, even for the angles to get in and out of a wash or stream ford. But I'd like it a lot more if one pair could lift for the inevitable 90% of travel on paved roads (meaning a rig light enough to be well within spec on just 4 wheels).

So the question really comes down to how much faster? And, could the little bit of extra speed that NeverEnough thinks would be desirable, on bad roads (again, not off-road), be had comfortably with single-axles and coil + air suspension? Or does the TerraLiner really need IS, to get the added bad-road speed that NeverEnough advocates so eloquently?


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Finally, here are some rear shots of the M-ATV, showing how close and how far from the ground the center-line of the vehicle can vary. In the last shot, the centerline once again definitely looks lower than the wheel centers:






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6. A Visual Analysis of TAK-4i in the L-ATV


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The L-ATV uses an updated, modified version of the TAK-4 suspension, called TAK-4i, where the "i" stands for “intelligent”.

Again, we'll start with some neutral frontal images of the vehicle without “bounce”. In these shots it seems pretty clear that the TAK-4 suspension has been modified to create center-line clearance that is actually higher than the wheel centers. In other words, TAK-4i as used in the L-ATV has a center-line clearance that is actually better than a Straight-Axle:







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Here are some side-shots, to provide an overall sense of what the L-ATV looks like:






And here is a sequence of “bounce” shots, demonstrating that even at the lowest point in the cycle, the updated TAK-4i suspension does not drop its center clearance below the wheel centers. It never becomes worse than a straight-axle suspension:





So perhaps the jury is still out; perhaps Independent Suspension might still prove desirable after all?

Sure, Independent Suspension is more complicated than Straight Axle. But if it were very robust, heavy-duty IS of the kind made by Hendrikson or Oshkosh, then perhaps it might be almost as problem-free as Straight Axle? And in the most recent TAK-4i implementation in particular, IS does seem to have the potential to raise the center-line of the vehicle higher than a straight axle could. Even in the "low point" of the cycle TAK-4i seems no worse than Straight Axle. If it could provide just that added bit of speed that NeverEnough thinks is desirable, in comfort, on bad roads. So perhaps Independent Suspension is still worth considering after all......

It sure would be good to hear from campo and NeverEnough on this issue.....

All best wishes,




Biotect