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Darpa Literally Reinvented the Wheel for Army Combat Vehicles

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Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#41

Post by detaro »

mrfusion wrote: post #38
cocktailpeanuts wrote: post #6

Earlier quoted context omitted.

read the article. it's the first sentence.

I mean what’s the benefit of this design for rough Terrian. Obviously I read the article.

As with any tracked vehicle: Larger, flat surface area touching the ground results in better grip on soft ground and is less prone to sinking in. Small track-sections like here obviously aren't as good at that as full, tank-style treads, but easier to add to a wheeled vehicle and allow normal steering.

There's all kinds of companies making conversion kits to such (non-shape-shifting) small tracks for trucks and SUVs, not sure if there's a military example of that exact style.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#42

Post by bengrunfeld »

As a previous soldier (commander of a hummer unit), there are serious challenges that the terrain offers. Bits of sand and rock get into EVERYTHING when you're driving over them. All those small complex moving parts could easily become a nightmare if they got stuck full of grit. Hopefully their engineering takes this into account.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#43

Post by gpm »

qaq wrote: post #35
Swizec wrote: post #20

Earlier quoted context omitted.

Humvees get stuck a lot! The US donated (I’m sure with wink wink strings attached) to us, Slovenia, some years ago and it was quickly found that they are too large and cumbersome for our foresty mountanous terrain. They’d get stuck all the time on tiny roads or between trees. I think these days they’re used for paraded to show we have them but day to day the military keeps using their trusti Puchs from who knows when…

US is not fighting in areas where getting stuck between trees is a big issue.

Given how much money the US spends on its military I'd expect them to be prepared to fight just about anywhere.

Certainly in "foresty mountanous terrain" since that isn't particularly rare. Exists inside of the US. Exists on both borders of the US. Etc.

Producing a military optimized for "blowing up unsophisticated enemies in desserts" seems like a very shorted sighted way to spend the military budget.

(None of the above should be taken as me defending spending so much on the military as a whole, just on the allocation of the budget within the military to all sorts of terrain when taking the size of the current budget as a given).

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#45

Post by Swizec »

qaq wrote: post #35
Swizec wrote: post #20

Earlier quoted context omitted.

Humvees get stuck a lot! The US donated (I’m sure with wink wink strings attached) to us, Slovenia, some years ago and it was quickly found that they are too large and cumbersome for our foresty mountanous terrain. They’d get stuck all the time on tiny roads or between trees. I think these days they’re used for paraded to show we have them but day to day the military keeps using their trusti Puchs from who knows when…

US is not fighting in areas where getting stuck between trees is a big issue.

They did in the mid 90’s when they participated in the balkan wars.

A lot of jungle wars before that.

I think the general desertiness of war theatres only applies in the last 30 years or so and is not likely to persist forever.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#46

Post by stefco_ »

namirez wrote: post #44

I don't understand the benefit of turning the whole wheel into a triangular track; would it not be sufficient to make only the bottom third flat?

Note that the whole assembly rotates when in wheel mode. Making it radially symmetric (i.e. a triangle) in track mode means that it can switch modes with at most a 120 degree rotation rather than having to rotate through up to 360 degrees to get the flat bottom into position.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#47

Post by mirimir »

rootusrootus wrote: post #36
mc32 wrote: post #31

Other than military applications. Looks like this could have potential for snow-bound vehicles. Ski areas and backcountry in the winter.

Definitely. The concept was commercialized years ago. E.g. http://www.zonepowertrack.com/en

Yes, but static.

And actually, it's an old thing, in that Model T conversion kits came out in 1922.[0] Also, later, for mud and sand.

0) http://www.modeltfordsnowmobile.com/lcmainbriefhistory.htm

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#48

Post by stefco_ »

solarkraft wrote: post #39
Avshalom wrote: post #30

Earlier quoted context omitted.

Still if that 3-4ft^2 is in the air it's useless. This doesn't stop high centering or driving into a ditch.

It does help with traction, though. That's an improvement over tires. However I wonder why they accept the complexity/reliability problems I assume come with this solution instead of going with added (engageable on demand) tracks.

Since it's DARPA it's pretty far from being fielded, so I should think they're only worried about proof of concept at this point. But if you could modularize and ruggedize the wheels and make them easily replaceable and compatible with existing vehicles, then I could certainly imagine this being quite practical in certain situations.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#49

Post by namirez »

stefco_ wrote: post #46
namirez wrote: post #44

I don't understand the benefit of turning the whole wheel into a triangular track; would it not be sufficient to make only the bottom third flat?

Note that the whole assembly rotates when in wheel mode. Making it radially symmetric (i.e. a triangle) in track mode means that it can switch modes with at most a 120 degree rotation rather than having to rotate through up to 360 degrees to get the flat bottom into position.

I didn't say anything about the design of it, which is by the way, very cool. I don't understand the point of the triangle. The same mechanism could be used to change the geometry of the wheel only at the bottom.

Re: Darpa Literally Reinvented the Wheel for Army Combat Vehicles

#50

Post by [deleted] »

namirez wrote: post #49
stefco_ wrote: post #46

Earlier quoted context omitted.

Note that the whole assembly rotates when in wheel mode. Making it radially symmetric (i.e. a triangle) in track mode means that it can switch modes with at most a 120 degree rotation rather than having to rotate through up to 360 degrees to get the flat bottom into position.

I didn't say anything about the design of it, which is by the way, very cool. I don't understand the point of the triangle. The same mechanism could be used to change the geometry of the wheel only at the bottom.

[deleted]
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