Outer Limits 4x4 Board

Did anyone happen to see the new inventors tonight?
They have invented a suspension system with only one differential, that has practically unlimited travel and always maintains equal ground pressure under each wheel. So as your front right wheel gets lifted (on a ramp for instance) this in turn put extra down pressure on your back right wheel, your front left wheel and your back left wheel. all four wheels maintain equal weights as if the vehicle was sitting flat.
check it out here. http://www.abc.net.au/newinventors/txt/s1181148.htm

Cool, i wonder if they want to trial it on a zook? Come to think of it a backhoe could be handy whilst wheeling.

Looks like it has a chain drive system to each wheel from the central axle. It would be handy only having to buy one diff lock to lock all four wheels.

Looks like an interesting system but I would like to see how the central axle connects to the rest of the tractor, and what they use to keep it level.

They say there next application is for quads, but I doubt it have doubts about how comfortable it would be at high speed over roght terrain like you get on a quad.

Theres nothing new here. Many 4x4, 6x6 and 8x8 military armoured cars have only one differential. Its known as a ''H'' drive transmission. these vehicles suffer terribly from transmission windup on hard surfaces.
Also, some European all wheel drive trucks (Swiss Saurer circa 1950's} had bellcrank interconnected front/rear suspensions to maintain all wheels in contact with the ground within the range of available travel.
Bill.

daddylonglegs wrote:these vehicles suffer terribly from transmission windup on hard surfaces.

I thought about that Bill, but the prototype in the vid has four wheel steering (counter steer, not crab steer) - so at least in this case both wheels on one side should describe the same arc around a corner - so there shouldn't really be any transmission windup???

Ben. there is always some transmission windup on bitumen, due to minor differences in tyre diameters even between the 2 diffs on a tandem rear bogie unless there is an interaxle differential. with only one diff the windup would occur more quickly. but for offroad tractors in difficult dangerous conditions, anything that can make there operation safer is commendable even if the design principals aren't really new.
Bill.

Bill have you seen the chainlink from the US (see below). Posibly a better application of similar technology. Each wheel can apparently be driven independently.

http://www.pirate4x4.com/forum/showthre ... nk+cameron

Yes Ben, its an amazing creation. I bet the drivers brain would be working overtime working all the different controls.
Bill.

Yes, I know what you mean - sometimes it is hard enough working the gears, steering and diff lock, let alone all the other controls that thing must have. There is definitely something said for simplicity of design.

ISUZUROVER wrote:..., and what they use to keep it level...

Ben,

As I understand it, there are some other linkages at one end - a transverse beam pivoting on centreline of the chassis with hydraulic links connecting the ends of this transverse beam to the ends of the walking beams, which has a similar effect as Bill's forced articulation.