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

[biotect]

View attachment 262383

Typical Rock slider on a Defender.

Hi optimusprime and thjakits,

When I tried to google what thjakits meant by "rock slider", I came across such images as well. thjakits, I thought that these might be what you were talking about, but could only find images of rock-sliders attached to SUV's. Because you were talking about them in a trucking context, it then seemed that I was on the wrong track. And that perhaps you meant something more like protection rails for trucks instead.

So it would be really helpful if either of you (or anyone else reading this) might be able to provide links or images for what a "rock slider" would look like on a much larger expedition truck, or construction truck, or other kind of large vehicle that has to deal with rocks.

The basic idea, I take it, is mainly to protect the side of the vehicle from rock walls, or individual big rocks that the vehicle is passing? These will scrape along the slider, but will not damage the body work, or the tires? But in this image, I can't see how the slider would protect the underside of the vehicle from rocks. But that's not what it is meant to do, right?

Might you have any videos of a rock-slider in action, especially on a vehicle bigger than an SUV?

All best wishes,



Biot

 

[optimusprime]

Just a couple of pics showing you how they basically work,the first one is probably the one that would concern us the most,as the last two pics show terrain that we wouldn't be travelling down.
As you can see,the sliders protect the lower bodywork from damage,enable the car to 'slide' over the obstruction without getting caught up and ripping bit of bodywork off. Also if the vehicle is 'sat' on say,a rock,there is a chance the bodywork may deform,as its not designed to take the weight of the vehicle on the sills.
I would suggest that the design and materials just get scaled up to suit the size of vehicle.

 

[dwh]

You won't see rock sliders per se on big heavy rigs. The pipework would have to be rather massive to support the weight of the truck. Another problem is that for rock sliders to be effective, they would have to be below the storage boxes. That presents an engineering geometry problem as regards how to transfer the entire weight of the truck up from the rock slider, around the storage boxes and eventually to the frame.


Most of the bigger trucks I've seen don't have anything to truly protect the storage boxes, though a few do have skid plates. But while skid plates will provide protection, they won't really service as rock sliders because the weight of the truck would probably crush them. The Orange truck has tons of pipework. If ever there was a truck that *could* have had rock sliders, that truck is it. But it doesn't - it has skid plates (click and click again to zoom):

 

[dwh]

Looking up close and personal at the full size image of the Orange truck - I see it has the same problem I mentioned about the other one - the pipework is not tied into a unified structure. So again, an example of fancy branch risers, but not rollover protection.

For example, the protection bar around the windshield. The downtubes just sort of stop and hang there. For structural rigidity, it would have been a simple matter to extend them down a bit more and tie them into the bull bar.

Also the side tubes on the living cabin - just like the other truck, the bottoms of the tubes just end and hang there. Not boxed in to create a unified structure.



As for the wire lifter. I think what he was referring to was a simple telescoping pole (made of fiberglass - not aluminum!) with something at the end to lift and support the overhead wire. I believe Stephen Stewart mentions having something like that in his kit.

As an old electrician, I can tell you that in the business, that tool is known as a "gopher pole":

http://www2.newtechindustries.com/newtech/catalog/telepole_twist_locking_push_pull.htm

 

[thjakits]

.....and another little bit:


OUTRIGGERS:

FCS! Bio, HOW tall do you want to go?? I totally agree to leveling jacks (and one on each corner should do the trick, thank you!), but outriggers??
Hopefully you design Terraliner so that most/all heavy gear is located as low as possible - [...do NOT put the smwimming pool on the roof!! ...though I would provide a hotwater tank on the roof to be able to use thermosyphon to solar-heat water - a fairly flat tank will work, drainable for driving and/or freezing temps....].
You are right about storage space limitations with many axles, but the location of these is NOT a problem. An axle needs a certain amount of space, wether it is in the front or the rear or the middle. Just use all the space in between, even if it is broken up.
Going the Serial Hybrid route - this is the only case where I could see an advantage with Independent Suspension - depending how short/long your suspension links are - you can have some long, uninterrupted space in the center of the truck. The shorter the links though, the worse the functioning of the suspension....see:

....more to this one later...

NOT enough reason for me to consider IS....

Anyway, if you are parking in a area with winds that high that you run the risk to be blown over, then align the truck with the wind!! And leave the roof down ANYWAY!!
With 3 axles you certainly have less storage space available - now DON'T waste it with OUTRIGGERS!!
For the one occasion you might want them, weather it out roof down, neck tucked in and pray! You WON'T ever see a 2nd occasion - you WILL do anything to avoid that!! If you cannot align the truck into the wind - you are in deep ******* - constantly turning winds with a strenght to blow over your truck without outriggers are called TORNADO/HURRICANE/TAIFUN and generally outriggers will make squat difference before you go flying.....

Leveling Jacks:

Absolutely! However you need to keep in mind truck access after leveling. At 10m+, unless you are on somewhat level terrain to start with (levelling...), you might get your acccess-door WAY off the ground! Be prepared to have some kind of foldable stairway:

AGAIN - keep it simple! Outriggers are WAY over the top!! ...don't believe me! Ask the Owners/Operators on here!!

This guy has different reasons for his system - AND it is leveling jacks, NOT outriggers. All the structure he needed to put these on, you can incorporate into the structure of Terraliner.

IF you are still intend to provide 4 hoisting points (to lift the rig onto a ship) you might just use the same structure points and calculations to mount jacks underneath. Depending on how sophisticated you decide to make the suspension, you might easily get away with non-powered jacks only, using the suspension to level the rig, then lowering the jacks and retracting the wheels enough to have the jacks take 90% of the load and you will have a rock-solid stay! This would certainly eliminate another hydraulic system with all its weight and possible leaks....
Though you could use electric jack-screws - easily backed up with a ratchet wrench.....

2 axles vs. 3 axles:

IF you stay intent to build ALL the stuff you mentioned in the last few pages (huge windows, that are strong, exceptional climate control abilities, adjustable transparency, lifting roof, hopefully slide-outs, window covers that might double as veranda shadows, etc....) you won't have to worry about your 16-ton limit. You won't make it. So 3 axles are just fine.

Yes you could make ALL axles steer, but again - for what purpose? Obviously you will be able to do limited OFF-ROAD after all, but the intention is to stay ON roads....All-Wheel-Steering is more interesting for rock crawlers and special work machinery....

The Solid Axle versus Independent Suspension debate, and the Problem with Portals

Only you and egn have explicitly advocated solid axles; everyone else seems to favor Independent Suspension, including experienced "real" explorers and overlanders like campo and NeverEnough. I have been deliberately sitting on the fence, because I personally lack the experience and knowledge necessary to decide one way or another, with regard to overlanding in an apartment.

I don't want to be patronizing over Campo or NeverEnough or anyone else really - THEY got rigs and use them!
HOWEVER, (unless locked away in a personal file....) I didn't see ANY indication that either Campo or NeverEnough or anyone else for that matter REALLY used the abilities of their rig anywhere close to their limit - ....and I doubt I would!! As Rob said -you don't want to risk ALL you GOT!
I believe to remember a pic of Campo's rig stuck in the sand - I can guarantee you that a Solid Axles is loads better in Sand than a IS - at least at the speeds you will reach with an Overlander....

You need to get more details on WHY they would prefer a IS, based on WHAT experience (...essentially what is their springing and damping systems)

Comparing a leaf sprung truck to a coil-sprung truck is NOT fair - now comparing it to a Air-suspension or Kinetic style one is outright insulting!!

So - you need to compare apples with apples: Coil-sprung SA vs. Coil-sprung IS (still might go for the IS)
Once you go Air-Suspension - no more reason for IS....

I think dwh is right, that Independent Suspension does not necessarily mean that the vehicle will have a lower centerline. The one image that dwh posted illustrates this perfectly

YOu are right - it IS possible!

NOw let's get into detail: The upper pic actually shows, that can do about the same ground clearance like a Solid Axle just fine with a IS - so WHY bother with the added complexity of a IS?? You could of course do an even more extreme IS - I counter with a Portal Axle or DeDion version of a Portal if you use hub-motors.

In the 2nd pick dwh shows a typical 80/90 US pickup truck front IS - the shown one has a typical IS-lift kit mounted. The factory IS is nearly level for the lower arms. AWD for these pickups is intended to get through winter, get through dirt roads and little muddy stuff on the farm or construction site.
They are NOT intended for OFF-roading or rock crawling!
Most people that wanted to do that anyway, would get a very expensive IS-lift kit, that many times just got enough space for the big tires, but actually LOWERED the differential to cope with the achilles heel of high articulation IS suspensions: driveshaft-angles! Be it a U-joint (cardan joint) or a CV-joint, they are severely limited by angles.
MOST people that wanted to do more extreme off-roading would do a Solid Axle swap!

The truck shown is probably a 150/250 series of any of the 3 truck US-truck providers - the same size but heavier 350 series would normally come with a Solid Front Axle.....[apparently the heavier use would take too much strain/reliability out of the IS]

With a steep IS suspension angle you also inherit another high wear item - lateral displacement of the wheel as the suspension cycles through its range, which becomes a VERY high wear issue not only on the tires but also the Suspension links once you really work the suspension going slow....
A solid Axle will only PIVOT around the tire contact patches....no laterally forcing the tire....
As mentioned before - IS becomes a serious factor when you need to control your truck at high speeds and when you start to need a pilot license (like in huge jumps at Rallies) - not with an Overlander. Even if you get yourself into a Life or Death situation and have to jump your Solid Axle Rig, with a well executed Air-suspension (or Kintec style one), you still will be okay, just not as fast and as to the edge as you could with a IS.
...by then you are breaking furniture and houshold gear left and right - Solid Axle OR IS.....

Further back in the thread there are a few pics of IS-trucks. They are most likely fast military or Rally machines - NOT regular transport and certainly not rolling apartments!
AND their lower arms are basically STRAIGHT out - mainly to avoid the pronounced lateral movement of the tires at the range where they will work 90% of the time....

No doubt you can build a proper IS for Terraliner, but WHY?? You can have a simpler, sturdier way with NO deficits for the intended purpose, WHY complicate things?

I don't know if this means that each wheel can be retracted individually; perhaps egn might know?

Just depends if the truck is plumbed/wired for that. Also depends if the air-bags are designed for "negative pressure" (vacuum) to suck the axle up. IF so, there will be some kind of locking device to keep the axle locked in the upper position. Also possible that there is separate set of air-bags that lift the axle via some linkage with positve pressure.... Google up on "Fullsize Truck and Trailer air-suspension" and knock yourself out!!

Portals:

As dwh stated, the trouble specifically with the Unimog axles is, that they are designed to go slow (relatively). Whenever "Unimog" comes to mind, one pictures SLOW to VERY slow, but incredible steep/broken/rough terrain. Some Unimogs have over 20 gears, depending what you ordered:

BTW: The speeds shown below are at max continuous motor rpm and the max speed in that gear....

Unimogs are made to do about ANYTHING you can imagine (...and then some you can't!), BUT travel long distances at high speeds (which in Mog-speak means 85-90 km/h - we are screaming at that speed!)
A Mog (modded 404 or 406) would be an excellent "Come-along" on the trailer behind the Terraliner. Perfect machine to go where you should NOT take the T-Liner!!

dwh is spot on, once you go past design rpms on gears (ANY gears, not just MOG portal-hubs) you are on borrowed time.
[MOST truck axles will have a planetary gear reduction at the hub and get seriously hot in the process - however they are designed for that...)

That said, Unimogs are not the only Portal axles out there.
For a truck the size of the Terraliner, Portals really become less and less necessary. Break-over angle becomes more important.
At the size of a 10-ton+ truck, your tire size will normally provide enough ground clearance below the axles - for most ROADS you will want to travel.

Still, having a truck axle built up with portal-hubs is not a big deal. Just needs to be calculated for the desired speeds and power levels.

Going Serial hybrid it will really depend on if you use a central motor per axle or hub motors on each wheel.

With hub-motors you really wouldn't need a Solid Axle anymore, but I would "copy" a Single Axle layout - that's what a DeDion axle is:
Keep the Straight Axle properties, but reduce unsprung weight by mounting the Diff on the chassis and drive the wheels with CV-jointed drive shafts.

Depending on the final layout I would make it a DeDion (with hub motors built in) or a Portal DeDion with the hub motors below the portal tube....


Look - IS is great if you need to negotiate fairly rough terrain or small obstacles at high speed - no doubt.
In an Explorer/Overlander you will NEVER negotiate ANYTHING at high speed! Any obstacle you need to pass you will do according to one of the basic rules of OFF-ROADING:

"Go as slow as possible and as fast as necessary!" - Sometimes you will need some inertia, so need to get some speed....but it will NEVER be that much that you need to consider a IS.

If you look at it carefully - you NEVER see a Rally-Truck doing big obstacles. ALWAYS rough roads and when they get air-borne it is NOT because of an obstacle, but because inertia doesn't let them follow the road (that is dropping away...)

Now let's look at negotiating rough/big/tall obstacles - have a look at Rock Crawling - 85% of all rigs will have Solid Axles - ...the other 15% will have Portals!!
[Ask them why they don't use IS - except for one or the other rig, which runs IS for a while and after a season you see most people back with SA...)
Same in Truck-Trials - except for the Tatra's ALL Solid Axle.
The reason for the Tatra suspension is NOT that swing axles are better, but that it keeps the drivetrain FAR away from any obstacle below!
However it now has to deal with the forced sideways movement of the tires as the swing-axles cycles!!
And frankly, I'd rather NOT have to worry about the Tatra drivetrain [...or the Pinzgauer drivetrain for that matter, ....rather take a Volvo C303 or C304 or C306 over any of the Pinzgauer versions, that do about the very same thing as the Volvos. AAMOF a modded Volvo C303 would be the perfect "Trailer-along" for my Skoolie project - if I ever get it off the ground!]

....everyone else seems to favor Independent Suspension, including experienced "real" explorers and overlanders like campo and NeverEnough.

...see above - ...somewhere

Don't know about NeverEnough, but I am pretty sure that Campo only knows his rig, which if I am not mistaken has leaf springs. I wish Campo could get a ride in a properly set up Air-Suspension truck with a Solid Axle - NE, what is your experience concerning Solid Axles on Air?


Bio - to me Solid Axles are not just simpler and sturdier than IS, they are hands down BETTER in SLOW OFFROAD conditions - whatever speed you might get to do with Terraliner - concerning this discussion it will always be SLOW!
And SLOW OFFROAD conditions is ALL what Terraliners AWD/ground clearance/break-over-angle(Turtleing)/2-3axle discussion is all about!!

If you need AWD just to get through the winter on general roads you don't need to build Terraliner, just take a bus chassis add e-drive to all wheels and you are done. But then forget NE-Siberia in Winter....or the OZ outback, ....or Africa...or Bolivia! You want as much ground clearance as possible, as simple as possible!


...to becontinued

 

[thjakits]

On the subject of mirrors, you want as many as you can practically have.
When driving a 'large' vehicle,they are your eyes,if you lose the use of your passenger side ones,you are BLIND down the entire length of thst side of the vehicle! ( in fact it is illegal to drive a large vehicle in the uk if the passenger side mirrors are missing or broken!

View attachment 262386
View attachment 262387

THANX OPTIMUSP!!

That's EXACTLY the pics to show the facts!!

Normally these mirrors are excellent and once you are used to a truck driver position and the visibility it provides AND the visibility you get from the mirrors - you will hate to have to get back into a mere car!!

thjakits

 

[thjakits]

Hi optimusprime and thjakits,

When I tried to google what thjakits meant by "rock slider", I came across such images as well. thjakits, I thought that these might be what you were talking about, but could only find images of rock-sliders attached to SUV's. Because you were talking about them in a trucking context, it then seemed that I was on the wrong track. And that perhaps you meant something more like protection rails for trucks instead.

So it would be really helpful if either of you (or anyone else reading this) might be able to provide links or images for what a "rock slider" would look like on a much larger expedition truck, or construction truck, or other kind of large vehicle that has to deal with rocks.

The basic idea, I take it, is mainly to protect the side of the vehicle from rock walls, or individual big rocks that the vehicle is passing? These will scrape along the slider, but will not damage the body work, or the tires? But in this image, I can't see how the slider would protect the underside of the vehicle from rocks. But that's not what it is meant to do, right?

Might you have any videos of a rock-slider in action, especially on a vehicle bigger than an SUV?

All best wishes,



Biot

Hey Bio,

"rock slider" - same thing and purpose.

I did not see any yet on a big rig (...possibly in Truck Trial) - the one shown for the Land Rover is not really ideal (unless it is extended all the way to the frame under the body. The trick with the Sliders is, that they MUST have a slopeing connection to the center/chassis - OR you might actually slide ON/OVER the rock instead of OFF the rock!! Getting high-centered on a rock ANYWHERE on the truck is mostly a royal pain in the bu**!!
Normally this entails lots of jacking work and then - HOW do you get the truck off the rock?
[Imagine you just jacked it up to get it off the rock, but HOW do move it away from the rock - being all up high on jacks?? ..sometimes you have no choice than trying to move the rock or even tackle to split it - major body workout!!]

Best yet is to have a complete plate from the chassis to below the body sill - though I never saw this yet on any Explorer/Overlander....

Google "Rock Sliders in Action" and "Rock Slider Build"

Here you have some plates extending to the chassis:

These ones are sturdy, but could actually trap you ON a rock if they slide the wrong way.....
Covering up the connecting tubes with a solid plate would solve this potential problem.

Just a UTV, but you get the idea!

Another fairly good one:

...check out the details:
http://white-knuckleoffroad.com/toyotafzj80.htm

True - nothing for big rigs yet, but I certainly would try to get SOMETHING in that direction.... and remember to make this a "replaceable wear part"


thjakits

 

[thjakits]

As for the wire lifter. I think what he was referring to was a simple telescoping pole (made of fiberglass - not aluminum!) with something at the end to lift and support the overhead wire. I believe Stephen Stewart mentions having something like that in his kit.

As an old electrician, I can tell you that in the business, that tool is known as a "gopher pole":

...absolutely right!! And even with the fibreglass one you will want to watch out if it is raining!!

Also you are right about Rock Sliders on big rigs - will/would be a major structural item - probably hard to implement in a existing chassis (....and most likely a reason why we don't see these) - as the Terraliner is a white sheet design - a good chance to incorporate something though!!

Maybe not even seperate slider tubes but just "wear plates" along the appropriately shaped underbody - replaceable if worn through!

Then I think OPTIMUSP is also right - Terralainer should not really need sliders - skidplates should be enough!


IF you leave SOME lift in the system when doing rough terrain you could just lift the suspension to the max ad get off any sticky situation....

thjakits

 

[dwh]

Trailing link:

Double wishbone:

 

[dwh]

Not actually sure what this is called:

 

[thjakits]

....last one for today:

Bio you mentioned steering-lock IS vs. SA:

NOT a IS vs. SA factor at all - If at all SA has the advantage as the U-joint/CV-joint only has to deal with 1 axis (vertical).
On the IS these also have to simultaniously deal with the 2. (horizontal) axis (from the up/down movement of the IS).

Really just depends how much of a joint angle you design into the system. The more angle you provide, the higher the risk that the joint might break sometime....

WITH hub motors mounted DIRECTLY on the hub - you would have none of these problems anyway - ....the sky is the limit - ...nearly:

Special Drift Set-up!!

Same for e-motor configuration. Wether you do a single motor in the chassis and drive a whole axle or a hub-motor on each wheel - NOTHING to do wether you use SA or IS configuration - you can do either on either!

Talking about hub-motors though, I suggest you get in touch with these guys:

Check it out: Motor Assembly starts at 01:06



Contact burried somewhere in there:

http://www.gizmag.com/electric-car-world-record-acceleration-eth/34563/

http://www.amzracing.ch/en/cars

The motors in this car are 37KW each.
On their website they mention a 40 KW version - (Check the "umbrail" car specs)

However I believe to have read (...somewhere!) that they have 70KW units up and running!
[Seems they are still developing and building them themselves!!]

If the 70KW units are not available yet - these guys certainly could build them! The 37kw units are only 3.4 kgs EACH!!!
At the tire-size and usual rim weights of the Terraliner-size truck - the motor weights just about disappear!!

With 70KW on each wheel you should have more than enough power for the Terraliner and basically ( at some level - at least on a dry highway - 6x redundancy!!) - even with a few units out - normally a e-motor has a time frame (before melting!!) to get you extra power (...up to double the rated power) - should the need arise!

A word to your power requirements:

I know Camo wants 500hp for his rig!! I tell you that is WAY TOO much for a 2-axle rig!
You really will never NEED that power! Camo might feel the need, because of his auto/semi-auto set-up. That's one item I certainly DON'T like on a Explorer Rig. Perfect for Long Distance Road Transport, but in a OFFroad/DIRTroad situation I'd rather have personal control over ALL my power and ALL my gears!!
If you have 500hp available it is just too easy to guzzle fuel (no matter if your final drive is electric - if you use 450kw you need to provide it - be it directly form the Diesel engine or via a generator...) - also it is very easy to break something if you don't use the power properly!

Figure it out: WHAT is your possible longest, steepest, straight (or max speed - take 85-90 km/h) climb you imagine (something like the Brenner Pass between Austria/Italy or similar stuff in the Rockies or the Himalayas) - WHAT power do you need to accelerate to and maintain that speed at MVGW with an additional 30 kt headwind/rain and pulling your trailer with your favorite toys anywhere on that slope? THAT's the max CONTINOUS power you need.....

A 42-ton 18-wheeler will not need the 500-600 hp they got today to maintain that - why would you at 1/2 the weight??

A 300KW power unit with a serious battery bank and 420KW capability on the wheels should make you a POWER-house/macho Truck amongst all of them out there!! ...and this unit should be efficient enough down at the max level you can pump into the battery bank when charging only....


Then some say: "You can have enough power, but never too much!!" :rally_guys:


'nough said! eepwall:

thjakits

 

[Haf-E]

I agree that there is a big difference between a solid axle suspension with coil/air suspension then one with leaf springs. Coil/air suspension allows a much better ride and articulation that can't be matched with leaf springs. Keep in mind that the Mercedes G-wagen still uses solid axles with coil springs - as do the MAN trucks and Unimogs. The Tatra's are available with a variety of options - from rear boogie leaf spring (also used on the rear of Pinzgauer 6x6s) to coil springs to air bags:

I think solid axles with coil or air suspension would be the most compact and yet highest clearance system possible.

On the topic of electric drive - I still believe that using one electric motor for each axle with a conventional driveshaft from the e-motor to the axle is the best solution - it allows the most redundancy and simplest yet most rugged design. With locking differentials in the axles the entire motor torque would be available on a single wheel - something not possible with individual hub motors. Using independent suspension would be challenging with the amount of torque available from a e-motor as the axle CVs would need to handle that torque.

Using conventional solid axles connected to the e-motors with standard drive shafts/u-joints also allows the motors to be tucked up high into the chassis - up out of the dirt, dust, water etc. If a motor fails the driveshaft could be pulled from it until it could be repaired / replaced.

 

[thjakits]

Not actually sure what this is called:

Don't know - ......"Bloody Nightmare" ??



...LOTS of wear on the rear wheels from getting dragged around corners.....




Other than that... - a nice big camper!

GMC Eleganza:

https://www.google.com/search?q=GMC...9FZOPgwS3zYKADw&ved=0CCUQsAQ&biw=1280&bih=642

https://history.gmheritagecenter.com/wiki/index.php/The_GMC_MotorHome


Rear-Suspension though quite innovative - in my book rather "on the edge" - it saves to air-bags and some air-lines, BUT there is a LOT of un-necessary forces going around in these suspension arms!

Rather have a bag on each wheel and the load transfered through the bag to the chassis.

The innovative part (one wheel rises and pushes the companion wheel down) - can be achieved by linking the individual air-bags....

ground clearance is STILL an issue or ESPECIALLY an issue:

Obviously only intended for mainly paved roads and manicured camp grounds, minimum suspension travel and it will high-center (turtle...)

Front-wheel drive only won't help much either once loaded for camping - but I am sure a soft floater when cruising the Highway!!

thjakits:bike_rider:

 

[thjakits]

I think solid axles with coil or air suspension would be the most compact and yet highest clearance system possible.

On the topic of electric drive - I still believe that using one electric motor for each axle with a conventional driveshaft from the e-motor to the axle is the best solution - it allows the most redundancy and simplest yet most rugged design. With locking differentials in the axles the entire motor torque would be available on a single wheel - something not possible with individual hub motors. Using independent suspension would be challenging with the amount of torque available from a e-motor as the axle CVs would need to handle that torque.

Using conventional solid axles connected to the e-motors with standard drive shafts/u-joints also allows the motors to be tucked up high into the chassis - up out of the dirt, dust, water etc. If a motor fails the driveshaft could be pulled from it until it could be repaired / replaced.

I think, that would the best approach!!

I belieive it would be possible to "lock" axles electrically, but it certainly would be a LOT of electronics involved - a "soft-locker" though should be possible, consdering the instant availability of max torque from the e-motors....
[The "electronic locker" on my VW Amarok works by using the ABS sensors and then applying (electronically controlled!!) the brakes accordingly - rather rough!! I got a ARB air-locker waiting to be installed in the rear-axle.....]

Also considering that Terraliner will probably NOT need any AWD for most of its live/kilometers - a single main drive-axle for most of the driving should be fine.
Make the other two with e-hub motors for stability (with a little e-trickery you can use these 4 motors perfectly for stability control and even "torque steering")
[That's were I was to use the hydro-drive hubs, ...until I saw the new hub-motors from my last post!!]

For the ultimate Serial Hybrid Ruggedness: 3x Solid Axles (portal or not) with switchable Lockers and a single big chunk e-motor/generator for each axle - and we are back at the Oshkosh power unit!!

Now we need to convince Bio, that there is really nothing to "Art Deco" under the rig!!



...next I will go back to post #853 where Bio started to aask loads of questions again - ...and see if I missed something - later.....



thjakits :coffeedrink:

 

[dwh]

Heh. I knew what the Eleganza was called.

Don't know the technical name for that sort of rear suspension setup. I'd probably call it some sort of "bogie".

The point I was making in the last couple of posts, was there is more than one way to skin a cat. I wasn't recommending a horse buggy suspension for an ExPo truck, or recommending the Eleganza setup - but simply illustrating the point that there are lots of different suspension systems.

Trailing link + semi-elliptical leafs + air bags is very common in semi-tractors. Sure, they have solid axles, but that same sort of suspension (with a few mods) would work for an electrical hub drive IS as well.

Something like this would work even with an electrical hub drive setup instead of a solid axle:

EDIT: Oops...forgot the link:

http://www.hendrickson-intl.com/Truck/Vocational/AR2



In other words - there are lots of options. Naturally, if biotect were to decide to use a trailing link on his concept truck, then it would have to something specifically engineered for that weight...the horse buggy airbag just ain't gonna cut it.

But there are ways to do an IS setup, with electrical hub drive that don't even *have* a center...so center height is irrelevant. Ground clearance is going to be whatever the frame height is.