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the future?


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Watching the local news this morning I came across a short report about a vehicle built by Portsmouth university. It is a new -stye mini with electric power, one motor per wheel built into the hubs, 900 mile range courtesy of an in car charging set (using a 20cc 2 stroke)and a top speed of 150 mph.

So, one motor per wheel, maximum torque from rest, no gearbox, driveshafts or props to snag....The possibilities for off road use abound once the issue of dirt ingress and waterproofing is addressed. It may be all pie in the sky now but I wager it shall not be long before those clever orientals put something in this vein onto the concept stand at a motor show soon. British innovation usually ends up in th products of others before us.

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Guest diesel_jim
Just can't see myself getting that tingly loins feeling from the high freq. whirr of leccy motors :lol:

unless it's an 8274! :D

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IMO for the concept to be successfull for an offroad vehicle there would need to be some mechanical interconnection between all 4 wheel motors. I can envisage a scenario when the vehicle is climbing a steep offcambered hill when most of the weight and traction is transferred to a single rear wheel, the electric motor in that wheel wouldn't have sufficient torque to keep the vehicle moving, whilst the other three lightly laden wheels with less traction would spin uselessly and the torque from their wheel motors would not assist the single wheel with traction. I believe a similar thing happens with twin engined Citroen 2CV Saharas when climbing steep hills. the rear engine unit stalls whilst the front engine over revs and spins the wheels.

Bill.

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Well clever electronics would stop the 3 wheels spinning but you'd have to over-spec the motors so that any one could propel the vehicle on it's own, which would add weight quite considerably. Water and dirt ingress shouldn't be difficult to overcome.

One major benefit I can see is there would be no axles or indeed other drivetrain to worry about, you could build a Frog-like vehicle but a lot less complex and more capable. Things like portals of any length you want, all-wheel-steer at any angle and no need for hi/lo/diff lock would all be plus points.

However, it would cost rather a lot as that stuff still does. You have a load of batteries to tuck away and unless you're spending NASA money there is no compact solution to holding lots of electrons. Control gear would be beefy, and would need to be reasonably intelligent for any level of off-road performance - read muchos development time.

As for eco-friendliness, emissions during running would be lower but you've gotta charge it from somewhere. Also batteries and electronics contain some really nasty stuff so emissions/waste during production and at end-of-life would be considerably higher.

I wonder how such a vehicle would stack up against a hydrostatic version of the same thing?

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Many, many years ago, when I worked in the mines, they had several different types of battery powered vehicles (BTW 4wd and 4w steer).

I remember an occasion when a fully loaded semi-trailer blew a diff pulling away from the truck loading bin. One of these battery vehicles with 20hp easily pulled the semi up hill off the road.

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DARPA have a fleet of 6 wheeled UAV for frontline battlefield use that seem to deal with pretty much anything put in front of them, diesel donkey motor driving a genny and battery pack with 6 in-wheel motors, theres a vid of it somewhere on youtube IMS

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Electric is definatley a way foreward.

Or perhaps a small nuclear reactor in each car?

Now we're talking! You get the plutonium, I'll do the rest.

There's a guy on Pirate looking at a hydro drive vehicle. So far I'm unconvinced. Mainly weight and speed limitations.

For the one-loaded wheel case using motors, I guess its straightforward-ish to stop the others spinning. As for providing extra torque to the loaded motor, how about running it at more volts? Maybe we could add a second motor? :ph34r::ph34r:

Hmm, I might look again at the hydro idea. :ph34r:

Al :D

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The problem is always going to be carrying enough electricity to do it. So you will need to make it as you need it.

This vehicle was claiming to do 900 miles between 'fill ups' (assuming I heard the BBC news correctly this morning :huh: ) ... I don't know enough to comment on the off-roading side of the technology, but as FF pointed out, I am very dubious about what's going to happen to all these batteries in 10 years time. I can't help but think the short term view of the politicans is creating a very real issue in the medium term :(

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But from the initial description, there are not vast numbers of batteries?

It appears to be a generator based system, so does this not make it more efficient, ie lighter, no lead acid batteries, no nasties to dispose of,.... etc?

I assume that the range is based on the fact that the vehicle is powered by a conventional 'engine' but it is being used as a generator to create the electricity, and being 20cc, its not going to be that consuming of fuel, is it? I geuss if it(generator) runs on waste veg oil, its 'green' too?

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....being 20cc, its not going to be that consuming of fuel, is it? I geuss if it(generator) runs on waste veg oil, its 'green' too?

It's not going to be powerful either - a chainsaw engine won't power a car.

The principle behind this is to power the car fom batteries and use the engine to top the batteries up. The work done by the engine running at max power throughout a journey would be same as the work expended by the vehicle. The batteries would provide power for accelerating and would also be topped up by regenerative braking.

It will find its place in stop-start town driving, I don't think it would be viable on the motorway.

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From the look of the hubs the motors themselves would appear to be axial flux motors which have some interesting qualities, particularly their ability to accelerate or deccelerate very quickly. I dont know a whole lot about them as all that moving magnet trickery is a little modern for my tired old bonce. I do know however that they are easy to build, many people build them for fun projects or as wind generators. So a homebuilt motor would of course not be up to the task of running a land rover, but it might be a fun project for an R/C car for those of you with an electronic disposition.

Just do a websearch on axialflux or axial airgap motors and you should find loads of plans and designs. for both motors and generators

With our IC engines there are so many ways we waste energy,maybe another way foward would be to harness what we lose. How about these for some "pie in the sky" energy recovery systems. a high pressure, hi temp cooling system with a tiny steam turbine generator. -Of course you would have to top up with water every time you topped up with fuel and the extra weight would probably negate any benefit.

Already it is possible to convert sound to electricity, indeed, that is exactly how a microphone works, the sound energy moves a magnet through a coil generating power. Perhaps one day intelligent underbonnet soundproofing will power our car stereo? Or perhaps an ultrasonic jetwash to shake off the mud.

I for one, shall mourn the passing of internal combustion, and I still believe there is more to be gained in it's further development, most particularly in the removal of the camshaft, the biggest limiting factor for modern EFI. Much work has been done in this field also.

Our beloved internal combustion engine itself seems to function almost as a living thing. Indeed they adhere to several of the principles for life, they respire, they convert matter to energy, and they respond to stimuli. It's quite a sobering thought that one could argue we may consider ourselves God's of a kind for bringing forth such "metallurgical life" but we mere mortals have some way to go before we consider creating in our own image...

As to the ultimate off roader, well that would be a goat. Fuel efficient too, they eat anything.

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Already it is possible to convert sound to electricity, indeed, that is exactly how a microphone works, the sound energy moves a magnet through a coil generating power.

That is interesting. My Landy generates so much sound I should be able to sell the excess electricity it makes to the ''grid'' and run the truck, and the city of Melbourne for virtually no cost to the environment.

Bill.

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That is interesting. My Landy generates so much sound I should be able to sell the excess electricity it makes to the ''grid'' and run the truck, and the city of Melbourne for virtually no cost to the environment.

Bill.

How about that for some green potential! Perhaps we could turn noisy school playgrounds and areas where women gather to gossip and chatter into"Sound farms" :D

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I read an article a couple of years ago about developments that were being done for the MOD (i think by Qinetiq) for off-road miliatry vehicles. The biggest advantages here with the electric drive were the extremely low noise output, and thermal signature compared to a conventional IC engined truck. If I recall reightly it was using the same basic idea of motors at each wheel station.

As for recovering wasted energy, there are turbo alternators that can extract significant amounts of power from the engine's exhaust- simply a turbo charger that drives a high speed alternator instead of a compressor. These seem to have some limited use in Combined Heat and Power (CHP) plants, but I have yet to find one that will fit on a conventional vehicle.

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My factory briefly looked into a CHP plant but with the rise in gas cost it was not viable to do.

An idea to run the motors.

Instead of using a DC motor use a 400v induction motor at each wheel. To increase speed just change the frequency via an inverter.

This could be run direct of a generator and would not require a battery or any form of DC in it.

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