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Let's spec out a 4WD EV


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"EVs will never make it to the farm." "EVs can't hack it in the Bush."

 

There's certain EV devotees who contribute here to the EV discussion who have got me thinking, "Why not?" All that is needed is a decent specification that is based on the realistic use of 4WD on farms and in rural areas. Let's restrict this 4WD to the farm workhorse. In fact, let's name it "Dobbin". We'll ignore the needs of recreational or the itinerant users of 4WDs.

 

1. RANGE

The majority of rural properties are located within 100 kms of a centre that can provide the things that a rural business and rural family need to operate. Therefore, Dobbin only needs an operating range of about 250 kms, or about 160 miles (for our American friends). This minimal range would allow for a smaller battery pack, releasing carrying capacity for a useful payload.

 

2. 4WD CAPABILITY

More often than not, the 4WD capability of the average farm vehicle is not required. What farmer goes out into the paddock if the ground is soft after rain? (Black soil plains excepted) Therefore Dobbin could be designed as a front-wheel drive vehicle with a smaller auxiliary motor for the rear axle that could be engaged as required. 

 

3. CARRYING CAPACITY

This factor affects the design of the chassis, suspension and brakes, and cargo area. Clearly, Dobbin needs to be able to carry as much as the ICE he is to replace. Sone Dobbin is a working horse, he doesn't need the polished harness brasses and plaited mane of a show pony. The greater use of "plastics" in the bodywork would be both functional and weight-saving. Mudguards that flexed instead of bending would be a welcome thing.

 

4. PASSIVE OCCUPANT SAFETY

Obviously Dobbin would meet the Passive Occupant Safety level required for registration and use on public roads. 

 

5. MAXIMUM SPEED

Dobbin would only need to be able to go fast when going to town. Since the maximum rural speed limit is 110 kph, a maximum speed of 120 kph would meet the need for speed, with a little left for when Dobbin was under the whip to pass an Itinerant.  Speed and range are linked to battery capacity, but determining the resultant bulk of the battery would take that into account.

 

6. RECHARGING

Like EVs used for personal use by urban dwellers, Dobbin could be given a feed of electrons whilst stabled up for the night at the homestead. It may even be possible to take a nosebag out to the paddock for him to top up while the occupants are attending to tasks at the yards or along the fence lines.

 

7. THE SHOW PONY

Every rural property has the "good car" for family transport and long distance travel. For quite a while yet, known to all the country as the Old Mass Shandrydan, the ICE will play its transport role.

 

 

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Many farms are irrigated and have uneven surfaces so you need 4 wd and a fair bit of ground clearance and you have to consider soil compaction effects with choice of tyres.  You also often tow a flat trailer  to put work tools or produce on..  Nev

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1 hour ago, facthunter said:

Many farms are irrigated and have uneven surfaces so you need 4 wd and a fair bit of ground clearance and you have to consider soil compaction effects with choice of tyres.  You also often tow a flat trailer  to put work tools or produce on..  Nev

Two good points added to the design spec.

 

8. GROUND CLEARANCE

Dobbin must be designed so that his belly doesn't scrape on the ground and his hooves don't sink in the mud.

 

9. TOWING CAPACITY

Dobbin must have the torque to begin a tow. This is a factor in the selection of the motor. The amount of torque required is related to the legal amount of weight a vehicle can tow. Towing capacities are calculated by a number of maximum weight limits. The three most important numbers are Gross Vehicle Mass (GVM), Gross Trailer Mass (GTM), and Gross Combined Mass (GCM). In short, the GCM must be less than the sum of the GVM and the GTM combined.

GCM < GVM + GTM

These numbers apply to any vehicle towing a trailer on a public road.

 

Any more suggestions?

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Large tyre contact area for low pressure  more grip and less soil compaction. You also need a fair bit of suspension travel for uneven areas at row ends etc or just only the front wheels if it has no suspension as tractors do..   Nev

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Most of the work has already been done with ICE vehicles with strong chassis and suspension, wheels and tyres and good ones are not cheap.

 

The advantage of the EV is no requirement for fancy transmissions. 2 speed electric would work easily and you could have one for each wheel but front and rear should suffice. and they do not require any mechanical linking.

 

Torque is a huge advantage as it is there from almost zero rpm & not reliant on an engine to wind up. Even in my 2wd EV the instant torque is something you have to experience to know how amazing it is.

 

Smallish swappable batteries would seem like a good idea as one could be on charge using solar panels while the other is in use. In China there are a number of EVs with swappable batteries that take less than 5 minutes to swap out. Then again if the battery was a decent size, say 300-400 km range, overnight charging would be easier.

 

Towing capacity would not be a problem either with power available. Look at diesel electric trains. The power train is electric. Direct diesel does not cut the mustard. But the battery needs to be a decent size.

 

Ground clearance would seem relatively easy. 4WDs are tall anyway and the battery could be right under the tray. The battery in my EV is as wide as the car & from firewall to in front of the motor at the rear but only 115mm high. A 4WD could be half that length but twice as high or more.

 

Wading depth and waterproofing are easier as well. A converted land cruiser to electric spent several hours driving under Darwin Harbour last year.

 

Weight is the only real issue and this is dependent on the size of the battery. My EV weighs 1670kg but feels as light as a feather & far easier to drive than an ICE car. It is the silent application of power and instant torque that provides this IMO.

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Surprisingly most 4X4 vehicle's have their ' air intake ' . In the most ridiculous places .

That's why most add the " snorkel " . Just to get clean air , as well as getting that same ' air-inlet above water .

( my. 4X4 was under the mudguard , in the dust of every convoy .only hours for a filter change)

spacesailor

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Driving these vehicles in salt water won't help them last. Just about every advertisement shows them doing it.. I worked on army ducks based on the GMC 6x6's in the 50's and undoing every nut and bolt was a challenge and keeping the brakes working  a full time job.   Nev

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I suppose my ideas on what a farm 4WD has to do is biased by where I live. Hard soil surfaces and no creeks to cross.

 

I was looking at an ICE 4WD today and realised that the weight of the engine and gearbox would most likely be close to the weight of the electric motor and a battery that would give 200 km highway range.

 

I also came to the thing that would kill the development of such a vehicle for Australia - the market might just be too small.

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Just as an aside to this, there are many companies overseas (and a few here" that specialise in converting classic cars to electric. Classic old Land Rovers seem to be a popular conversion.

 

 

 

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All of this is quite possible and viable given the huge expense of a new 4wd and the massive expense of current ev utes.

 

The fast take up of conversion kits and reuse of crashed ev's makes reuse of existing ice models a easy job and could be a lot cheaper than buying a good ic ute new.

 

A $20,000 budget plus donor ute could easily produce a electric ute that would do anything the ice version did but better. Electric is ideal on farm with a proper charging system for isolated power.

 

A dead Tesla ie crashed can produce a full setup with a huge 100kwhr battery and ridiculous power and unheard of torque with full 4wd ability.  If you don't need huge range, remember at farm speeds and regeneration you are efficient, then make smaller battery packs.

 

One 50kwhr pack in the truck and one 50kwhr pack to fast charge from and as a huge solar storage bank for the farm.

No power costs for the farm, anything run previously on diesel can be cheaply electrified ,eg stationary pumps, generators become obselete.

 

A 50kwhr pack is at the huge Tesla voltage of 300v minimum, so at 240v you have approx 62.5kwhr at 240v as a farm source. That compared to a normal house with solar and a telsa Powerwall or equivalent of 5-10kwhr is huge and at a similar cost.

 

A 10-20 kw solar array would be more than sufficient and economic to do as the prices keep falling. 

Use the array as a roof for shelter of animals etc for duel use. You can get new cells under $500 kw and the bulging second hand market at less than a $100kw for cells that a still good. 

 

So a budget of minimum $2000 for old and $10,000 for new plus controllers and structures would be a 20 kw system.

 

Add $2k -$10k for system management/ switchboard/ inverters etc and a potential huge system can be really cheap .

 

So let's work through it cost wise,

 

 

Original donor 4wd ute say perfect for use but engine/box fucked, $1000- $20,000 for a great late model.

 

Cost of a "crashed Tesla or equivalent" with approx 100kwhr at 300v is $20,000 just for full drive train and all electrics.

 

The solar array  and conversion of half the Tesla pack to a 62.5kwhr charging station/farm electrical power including all electric management is $4,000-$20,000. This is dependant on used or new items been used.

 

I know these are spitball prices but not far from what's possible as long as you do a fair bit yourself. Sure you might need a kitty of $10k above to cover extras and any engineered parts for the conversion but mainly it's within the realm of your average smart cookie farmer.

 

So using the high price for all new when possible and a real nice modern ute for approx $70,000 as the high spec late model version.

 

Voila, you get a great electric ute with huge power and quiet as a pussycat. You also never pay a fuel or electrical bill again. 

 

You are independent and a huge cost yearly has disappeared.

 

Sounds like a good idea.

 

 

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6 minutes ago, onetrack said:

I just hope and pray that Lucas has nothing to do with the electric Landrover installation, or you'd spend a lot of time pushing it, or getting it towed.

Lord Lucas, the Prince of Darkness.

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2 hours ago, old man emu said:

I suppose my ideas on what a farm 4WD has to do is biased by where I live. Hard soil surfaces and no creeks to cross.

 

I was looking at an ICE 4WD today and realised that the weight of the engine and gearbox would most likely be close to the weight of the electric motor and a battery that would give 200 km highway range.

 

I also came to the thing that would kill the development of such a vehicle for Australia - the market might just be too small.

I would not be too concerned about 4wd and water if designed for purpose.  They have developed and now selling inwheel motors that are fully sealed and weigh less than 30kg, the controller is also in the wheel motor.

 

It means bar simple suspension, wheel motors and battery pack you have what's needed plus a chassis. No trad engine,gearboxes, diffs,shafts and all the huge associated weights. No need to design along old school visions, but purely form equals function. Want the wheels at the end with huge angles of clearance? No problem

 

Plastic recycled panels that are tough and a huge tray that's at hip height no higher. Could be lower as a skateboard electric design.  Adjustable air suspension would be nice to suit any situation .

 

Onboard 240v power for tools is essential as is but directional charging. This expands it to the real tradie market not the pretend highlux boys.

 

Must have a bed 2.5 metres long by 1.8wide minimum, if it can't take a motorbike or full ply  sheet and spare, then it's just more of the same crap. Lots of utes can't even take a bloody push bike without the rear down.  As it's a skateboard design it's easy to lengthen the chassis at that just needs longer beams. A 4m tray would be possible. The inwheel motors allow custom architecture at low cost and small numbers not traditional car scale. Modular systems is the key to reduce cost and maximize production ability at scales the market can take with low capital requirements.

 

It should be two door and three across the front if wished or just two seat with huge centre storage. It must have good safety, be quiet, comfy and ergonomic design at heart. A twin cab just tends to be wasted space and a huge load reduction, the back row is crap for comfort and safety and at the same times is shit to store stuff. A below tray storage area could be huge and keep stuff safe and low. Think the storage under a old VW Kombi single cab and that huge long tray but the storage is back loaded as well where the engine used to be. No drivetrain obstructions just a 8'by 5' by 2'high storage, all safe below the tray. 

 

I need to get out my crayons

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Sadly, the Australian  startup that was claiming to have developed a car hub motor seems to have been very  quiet  about it since their announcement  ten years  ago.

 

If/when a viable hub motor comes into production,  that will be a great game changer indeed.

 

It would be great to ditch all those heavy diffs and gearboxes.

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There are many issues with in wheel motors and its all around vibration and damping due to the wheel taking all the shock load. There is a lot of research and work going in to how to make these  reliable.

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Whoa there. buckaroos!

 

I should have specified the principle governing the design of Dobbin. That principle is KISS.

 

What if we accept that the things that make an ICE farm 4WD have already been sorted out? What we want to do is exchange one source of torque with another and get a better means of transmitting that torque to where it can do work. One thing that seems to be reducing the efficiency (ie how long it is before the battery is discharged) is that an electric motor gives close to 100% of its torque immediately. Maybe it would be sensible to link the motor to a gearbox so that the application of the torque is more controlled.

 

Like an aeroplane, weight is the enemy.  When you consider that a farm ute is simply a flat cargo bed on four wheels with a seat for the operator/offsider, then there are many assemblies on a modern ute that could be replicated in lighter materials. 

 

Of course, to produce a vehicle that can be used on public roads, one would have to comply with the Design Rules, and passive passenger safety is one of those. However, if one took an approved ICE body as a base, these matters should be accounted for in the design of the EV replacement.

 

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Compliance Rules.

The rear lights on Australian cars are supposed to be at a designated hight .

But , that doesn't count for some ' imports. 

Then there's the separate bumper  that has to withstand a low-speed knock .

spacesailor 

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OME, did you watch that Land Rover EV conversion kit?

 

It is really well thought out. Everything bolts right onto the existing  chassis. The biggest part of the conversion is the removal of all the ICE components.

 

If you disregard the fact that they are marketing to the top end of the food chain, with the top sports motors out of Tesla, it should be just as possible to make a lower powered version for an appordable price.

 

By the way, we once had a Land Rover Freelander that had plastic front mudguards - they were practically impossible to dent... should be a feature of all cars.

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9 hours ago, nomadpete said:

OME, did you watch that Land Rover EV conversion kit?

Forgive me, but I did not watch that particular video because from the context in which you uploaded it I got the gist of its contents.

 

While such conversions have been carried out as individual projects or for testing purposes such as the conversion of bulk cement carrier trucks from diesel to EV, I was suggesting that a vehicle manufacturer design a 4WD EV for mass production from a "blank sheet of paper". To do so, a design specification would have to be created.  Creating that's the basis of this thread.

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BUT

Hasn't that been tried & tested . Found wanting  ! .

Leyland P76.

 Boot big enough to carry a 200 ltrs drum . had to be V8 .

And other Australian  innovations. 

Worth a fortune now . An American speedboat racer , bought All the motors & spares from NZ.

spacesailor

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15 hours ago, old man emu said:

Forgive me, but I did not watch that particular video because from the context in which you uploaded it I got the gist of its contents.

 

While such conversions have been carried out as individual projects or for testing purposes such as the conversion of bulk cement carrier trucks from diesel to EV, I was suggesting that a vehicle manufacturer design a 4WD EV for mass production from a "blank sheet of paper". To do so, a design specification would have to be created.  Creating that's the basis of this thread.

Ok,

 

Let's develop a specifications list.

 

 Blank sheets really are the best start.

 

I suggest a skateboard style design with individual wheel motor modules that also do suspension and steer. These designs are already coming to market. Quadruple redundancy, simple and efficient. 

 

This frees up the design and greatly reduces cost by buying off OEMs where possible.

 

Skateboard design allows anything from a van/bus, ute, wagon or even a car.  

It also provides full independent 4wd with no power transmission systems bar the wheel motors. 

Traction control, regeneration braking.

Independent adjustable suspension in height -  this allows instantly variable suspension  and power at any wheel to suit the terrain or on road conditions. That allows a comfortable ride and sporty/safe handling. It also reduces greatly the structural requirements to put up with the normal pounding a rugged old design needs.

 

This allows for a far lighter overall structure over any current model and still meet specs. 

 

It should be no more than 1500kg as a basic affordable machine.   It is scalable by design to allow larger range and weight load options. It should not try to compete with the huge expensive high utes, it's not. But will take a far larger load in back and easy to unload. And can cover areas hard work for a trad ute.

 

Loading height is 300mm or less with suspension dropped to allow easy and safe loading of stuff/bikes/ sheep  or hay bales etc. No big ramps required,  they are simple plastic slide outs. Can be side load as well.

These features are a step change in on farm OH&S to reduce injuries. 

 

It's a new way of moving stuff easily around a farm, not breaking ya back and the family can get to town. 

 

The extremely low loading height means animal management is far easier and no supporting ramps with side cages etc are needed, assuming nice beasts. Walking a calve onboard is easy.

 

Plastic panelled and cheaply easily customisable/ reconfigurable. An alloy structure with inbuilt roll bar of high strength alloy  steel.  Normal safety features.  

 

It does not look like a ute but more a  very short bonnet vw tray back in shape, but modern and a ultra low  long tray that can still raise to normal heights. The wheels are at the ends for extreme approach and depart angles. This also maximizes load space. 

 

 

It looks pure form is function, as we expected a 2025 design would be back in the last millennium.

 

 

Sorry no etchings as done on a $100 tablet.

 

 

 

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