Hi Bio, Campo!!
Well - Bio - no worries - "The Devil's Advocate" will not go away!!
I feel, I did step on a few nerve-ends though - GOOD!! Makes you think, doesn't it.....
Also, no worries about detailed answers - answer what you NEED to answer, DON'T repeat (just point me where you answered before....)
I know you will be busy, again - no worries!!
Bio - you do whatever you HAVE to do and I wish you all the best with it - hopefully you prove me wrong and Terraliner will actually be built!
One or two or thousands!!
The more "heated" arguments become, the more energy you will put into proving that your's is right!
You are a young design student and a strong head is good - I am a 50 year old (nearly....) hands-on guy with plenty of "less than desirable infrastructure" experience...
Ethical Engineering or Engineering ethics - no idea what ethics in engineering in the context of this discussion and/or vehicle/transport design means.
I just googled Engineering Ethics and what appears is more like a list of the 10 commandments (mostly common sense human nature rules) - obviously you can design against all this, but I doubt you have much success with it. To me it seems ethics in engineering are more about safety, design rights, etc....
No hurry, but maybe you could sum up what engineering ethics refer to in regards to your Terraliner project.
BTW: Take your time to read it all - a week or two if you need!!
Windows eeh!! Look , I understand your desire for big windows and YOU understand my arguments against them - good! At the end it is YOUR design, you do what you find you must do!
Hopefully an constructive argument:
[Maybe this HAS to do with ethics!??] Imagine your elderly couple is somewhere NE in deep Siberia in the middle of the winter (...as this seems the easier and preferred method to roam about there...) - a truck in front of them lifts a rock off the road and smashes the big windshield.
Next you know they a frozen to death, because while trying anything and all, they where not able to close the big hole in front.
Take ENGs KAT - about any squarish piece of plywood or table-top or anything in the truck can be cut to size and "fixed" in place - maybe not perfect, but it works!
Mostly NEVER happening, but remember - Devil's Advocate !! :campfire:
Now to the suggestion - Have another look at Rob Gray's Wothahellizat: HUGE windows and open space - WHEN PARKED!
ALL closed up when driving!! Small frontal area windows!!
'nough said! DA
No worries - I don't like this either on any the regular derivatives - I LOVED to drive the Renault Mangum!!! Absolutely fantastic to drive ABOVE the traffic - I was FLOATING really, loads of power - 480hp, 16 gears, nothing stops you - but a ridiculous huge windshield. Never broke one, though.
Wouldn't have mattered too much as I was the King of the Highway throughout Europe (call your preferred road-service or insurance), ......not in the most remote corner of the globe, where humans built a road ages ago and now live 500km away.....
I suggest, that you at least think about some kind of protective cover for all of the top-part of the window you really don't need during driving - carbon-fibre shield to pull down on the outside while driving, might also work as a thermoshield for the night.....
WHY ARE the front-window screens so popular in Oz?!!!!
Self-repair-ability (just too make sure we talk the same terms: This means, that
I as the owner/driver am able to fix basic things, like changing an injector on my diesel, fix ruptured hoses - fuel, hydraulics, air - etc....) - if you don't want me to touch anything, maybe better I don't go where I could run into trouble and not get proper service - .....soo, WHY would I need the Terraliner then?? DA!
I suggest you include certain spares in the "Remote Travel Action"-Kit!
Redundancy: Always good, but if we talk driveline, it will get complex and heavy quickly - AND: If you think because you use a separate motor (electric) for each drivewheel you are redundant - think again! As soon as you go places where you NEED AWD your highway redundancy is gone! If you NEED all wheels driven - redundancy is NOT! Spare wheel/tire/hub (if it includes the e-motor or hydraulic motor) will save the day, IF you are able to change the unit (Self-repairability!!)
I know, if you drive - you should be able to get your spare on/off - well, cars is one thing, Expedition-Gear and Terraliners are different one!
Drivetrain:
I never argued AGAINST a Serial-hybrid, contrary!! I argued against thinking "Electro Truck with a pusher diesel-gen set".
With today's (...and the next 4 years) battery and solar tech, and charging station infrastructure - you won't get very far on a battery-charge.
THe argument is that your e-motor energy will mostly NOT come from the battery pack but from a DIESEL-GENERATOR UNIT.
My argument was (sorry if I did not properly express this...) - to concentrate on the energy-recovery aspect of a hybrid drive - ...and
yes, DEFINITELY series hybrid!! Do away with all transmissions/transfers and drive by e-motor! If you still want/need to use a conventional rear axle and a single big motor driving that (more likely a single motor in line where rear-axle would be with separate driveshafts to the wheels - still would need a differential and locker there) or if you want to use separate e-motors on the chassis with shaft-drives or if you can use a separate hub-motor, NO IDEA!! You need to talk to your engineering friends! From looking at hub-motors as recently as a year ago for a van-conversion (Toyota Hi-Ace like...) - they where not very appealing for their un-sprung weight - I'd rather would go for chassis-mounted motors + drive shafts for each wheel.
At the end it depends all on the weight and efficiency of the whole package. Electric Motors are great - and HEAVY!!
So - if you go that route (I am all for it, but you will have to calculate VERY careful if full-time diesel electric is more efficient than a conventional drivetrain - I certainly hope it is!)
To help you out to talk to the engineering guys and for what I think Terraliner needs for a drive-line:
[I know you like the MAN/KAT/TATRA chassis or even just parts of them, but for the Hybrid drive concept they are no good and frankly WAY more than you need! If you insist in any of these chassis/drivelines, then you are better off going the convetional Diesel/Trans/Transfer-route. Try to incorporate a electric energy recovery system to get better overall fuel economy - parallel hybrid]
A] Conventional Rear-drive only Turbo-Diesel/Ecosplit-16 to normal rear-drive axle with a lockable diff.
If possible incorporate parallel hybrid for energy recovery.
Use hydraulic hub motors for all other wheel positions - as you probably already figured out, these are on demand only.
Hydraulic pump is driven of the transmission on there MAN and Renault, Mercedes drives the pump of the engine.
[
Hydro-drives: ALL the Truck-hydro-drives we are talking here are just about the SAME!! ALL use the POCLAIN patent and most-likely even poclain-units!
BTW: Poclain has also a energy recovery system based on the same system, using the motors as pumps and putting pressure in a tank, which then is used later to drive the motors again....no idea up to what speed this works, but the MAN drive switches off AWD at 30km/h+, Renault dares to push it to 40 km/h.
Bio, you seem to be WAY better finding references online - if you cannot find more on Optidrive, I certainly can't either! BUT, no worries - it is absolutely the same as MAN - I guarantee you the hub-motors are one and the same!! Pumps and electronics may differ, but I would suggest they are the same too, but adjusted for their respective clients!
If you do end up incorporating hydro-drive - contact POCLAIN - they should be jumping on the opportunity to help you out and get their system into the mouths/minds of the TRAVEL-crowd!!]
B1] BIG single or dual e-motors for rear drive. Hydraulic hub motors all other wheels - possible argument see B2
B2] E-hub motors on all wheels! This will very much depend on how much performance you get from available units - I kind of doubt you will get anywher near enough power for the WEIGHT you will hang on the wheels. On extreme offroad you might have an advantage with a heavy wheel, but on anything with a little speed it becomes hard on everything. Besides if imagine my e-hub-motor going down a washboard - that is really not "ethical" towards my e-hub-motor!! DA! Compared to a hydraulic motor an e-motor will always be WAY more sensible to road-impacts! (Again, I just don't think you will have powerful enough and at the same time light-weight enough units available anyway...)
B3] Chassis-mounted e-motors on all wheels! This would be the very preferred solution!! Here it will depend on on:
b3a] Are available units available that are not too heavy, are able to be used for energy recovery (not all e-motors are useful for that - risking to be supersmart: There is a millionand3 different e-motor designs out there!!] ....and are too bulky (taking away lots of storage space)
b3b] Considering the average need for AWD, do you really need permanent AWD? Running 6 motors vs 2 bigger units (or even 1 big unit only) on main drive-axle, is most certainly less efficient! Smaller units are always less efficient than bigger ones and if you multiply the losses it gets worse.
So - do you expect to NEED AWD permanently or rather only occasionally?!
If only driving the main drive axle by 1 or 2 bigger e-motors, it would most likely be more efficient to STILL use hydraulic hub motors on all other wheels.
I really have no idea about it, but considering Poclains research into this - hydraulic motors must have a WAY better power to weight ration than e-motors for this application! Not even to talk about impact sturdiness!
[Besides, with a good tool-set ("OFF-ROAD Action Rescue"-Kit option, DA!) you can take a hub-motor apart and fix it - all you should need is a seal pack..... Fixing a e-hub-motor out there, ....going to be tough even if you have a professional shop available]
Even with e-motors on the rear-axle only you still can recover energy via these e-drive motors. As we are talking full serial-hybrid drive train (albeit your main power source are not batteries, but a optimized diesel-generator], your hydraulic pump (for the hydro-drives) should be powered by an e-motor - [BETTER yet you should run TWO hydro-pumps of the TWO rear-axle e-motors!! The beauty of this hydro-drive system is, that if it is disengaged it is "transparent" - it does not eat-up any energy!
Damn - I should patent this concept!!] , this way you can use the hydro-motors to recover energy too by driving the system as a hydraulic generator unit. Obviously you will do this only if road-conditions require AWD for braking purposes - most likely you will be below the 40km/h limit by then....
Frankly you will actually have to consult with a hybrid-drive wizard to get the final configuration if you want the most efficient (most miles for the least fuel) drive-train!!
You will have to define the parameters very carefully - you mentioned a few posts back "mostly paved highway" - that already rules out any of the MAN/KAT/TATRA chassis if efficiency is the goal....
All the other configurations mentioned above are possible, just depends on AWD need priorities (how much time of the driving time do you expect to NEED AWD?!) and then on the different efficiency calculations between motor-typs, hydro-drive combo, etc... - weight of course also enters here.
Design-aesthetics: I DO like the MAN/KAT style, but I certainly do like a more elegant style just as well!
The oz trailer-camper you listed again on your answer post-series is a beautiful sample - and if I am not totally wrong (..studying the images) - there is hardly ANY compound curve on it!! Nice rounded corners and some elegant angles! From looking at it I probably could fix any hole or crack by epoxying even a piece of cardboard or any other "sheet" on it! The Bit** of repairs are compound curves - as long as you can do by just bending a flat piece in ONE dimension you win!
[Take a rectangular piece of cardboard or even a piece of paper and twist/bend it - whatever shape you can produce like this is okay - not flat, but any "flat piece" of something and it can be fixed - try to bend/form your piece of cardboard/paper over a ball - .....you get the idea...
Spare-Generator: Obviously this makes all the sense if you run a conventional rig/drive-line - Awfully inefficient to idle the drive-motor to get a few watts or even KW out of it for camping out.
HOWEVER if we are talking SERIAL-HYBRID drive, you do NOT HAVE a DRIVE-motor! You have a Highpower Diesel-GENERATOR SET!!
WHY would you need a small camping-genset??
IF you go SERIAL-HYBRID with a DIESEL-ELECTRIC drive system, OF COURSE you would design your battery pack so it can run everything on the travel rig as well, NOT just the drive!! After all, you will spend extend times NOT driving, so might as well appreciate the battery part of the hybrid system.
The idea is: even though the battery pack is mainly for energy recovery/efficiency purposes and your main drive fuel is still diesel (to power the generator set), with a rig this size you still will need a SUBSTANTIAL battery pack to accommodate the recovered energy from long downhill parts and continued braking. More likely than not that battery will maintain you up and running for a good while camping.
All you really need is that you can charge the pack with a sufficiently high charging rate, that you get at the minimum EFFICIENT running level of the DRIVE-GENERATOR system. Then automatic control will start up the big diesel, run it to efficient-speed-low-power-charge-level and your pack is up and running again in 45 min max.
No need for a small standby! That one would be no where near big enough to drive the rig anyway, just another heavy piece that can break.
If your SERIAL-HYBRID-DIESEL-ELECTRIC system is not reliable enough to stand alone - I wouldn't want it as a dual system either!
It get's way complex once you start with dual-systems (I fly helicopters for a living - I KNOW about dual-system complexity!!)
Show me ONE truck, Expedition vehicle, motor-home, offroad-camper that has a 2nd drive-motor and/or transmission!!
I certainly understand the idea about a camping generator unit - if it is a big one probably 10kw turbo-diesel? !!
For what you want you need a generally reliable unit - like millions of truck diesels out there - if you can't get that, you loose.
[For the sake of your design exercise, I suggest you assume similar reliability - no matter what power system you end up with]
If you replace old with new tech, there MUST be some benefit - in this case weight/efficiency/etc. - however if you cannot match the RELIABILITY of the old tech at the same time - you are going backwards.
I do, understand your notion of redundancy, but it does not reach efficiently to road vehicles yet! Even in helicopters TWIN engines reach redundancy only recently - in earlier days TWIN-ENGINE was more a liability, you NEEDED two engines to get the power to fly!!
What you want to do though is, design into your Terraliner "manufacture-flaw-survivability" - if you extend this latest helicopter manufacturing procedure to your design, you virtually guarantee, that even a undetected manufacturing flaw will not compromise safety and/functionality in any way!
In your last series-post you mentioned "turtleing" - would that be the break-over angle?
Concerning your
vehicle dimensions: By definition of your Terraliner (the list) you will never get to a point where this is of any concern, as long as you maintain a decent general ground clearance you are not going such extreme roads.
Be aware, that there a various legal limitations out there - with an axle load of 11-something tons like the Australian special built - you are off limits anywhere in Europe. Max 10 tons!!
Max single vehicle length is 12m and max combined tractor-trailer is 18m [General rules - exceptions exist for specific areas - Netherlands and Sweden and possibly in Finland - things start to go a little more Road-Train direction!
]
TOAD: DON'T!! Just look at the pictures of the Oz-fellow with the special build - what for Christ-Sakes did the poor Wrangler do, to deserve such a flogging!! And then all the extra gear to try to avoid damage to it! Just get it on an enclosed trailer and keep the bike there too - ...and fix it up so you cna use it as a workshop too, should you need to fix something! Saves a lot on those special OFF-road tires, that you use to go places you do not want to risk with the Terraliner! DA!
Also is more aerodynamic and probably saves fuel in the process!
Well, let me know if I didn't answer anything you specifically requested - sorry for all the grammar and orthographic errors - too late and too tired for proofreading!
Cheers,
thjakits
"DA!"
......let me know when you feel the need for more d-advocating!
