[OT] Mecha - coming to a forest near you!

[quoted original message omitted]

A subsidiary of John Deere is developing a hexapod machine for logging. Check
out the videos of it walking in the
woods - very impressive.  If you squint a little you can
see it armed and chasing infantry...

http://www.plustech.fi/Walking1.html

That wants rocket pods and miniguns and it wants them right now.

It's a Finnish domain, maybe you could paint it white and add skis...

But it's a John Deere company so olive drab is probably right.

> Ted Arlauskas wrote:

> A subsidiary of John Deere is developing a hexapod machine

Ted Arlauskas schrieb:
> A subsidiary of John Deere is developing a hexapod

Cool...
When do we get the Ds2 and SG minis?

Greetings

> At 11:12 PM -0700 6/19/02, Ted Arlauskas wrote:

It'll have to get a lot faster than that before it's chasing infantry....

Everybody has to sleep sometime... Bwahahahaha!

> On Thursday, June 20, 2002, at 06:09 AM, Ryan Gill wrote:

I believe a Swedish company has had something similar for several years now.
But very cool.

3B^2

> From: "Ted Arlauskas" <ted@naxera.com>

Well, from the video, it seems it could go after quadriplegic infantry with no
problems:) So what exactly could this thing do that a vehicle with catepillar
tracks couldn't?

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I think the key selling point is reducing damage to the forest... Presumably
it would be a little better on extremely bumpy ground, but a 60-ton tank
on treads does pretty good, too. Not too healthy for the ground, however.

It should be able to handle steeper grades and higher embankments than treaded
vehicles, although that isn't very clear from the pics.

I'd bet maintenance is worse than treads, and will probably remain worse no
matter how much they improve the design.

A walker with 5 legs could probably get around better than a tank with one
tread.

on 02.6.21 10:44 AM, Control Robot at cqin@ee.ualberta.ca scribbleth:
> So what exactly could this thing do that a vehicle with catepillar

> At 7:44 PM -0600 6/20/02, Control Robot wrote:

Well, from a forestry standpoint it can get over some pretty unusual terrain
that you'd need a very large front approach angle on the front of the vehicle.

IT can also move sideways and in odd directions that tracked vehicles can't do
even if they neutral stear.

> At 10:54 AM +0900 6/21/02, Edward Lipsett wrote:
Presumably
> it would be a little better on extremely bumpy ground, but a 60-ton

Ground pressure is going to be far higher than a tracked vehicle. However,
being able to place individual legs over a large log and ignore said log would
be a great benefit to mobitily.

> I'd bet maintenance is worse than treads, and will probably remain

Well it's going to be all hydraulically controlled and nicely sealed. Seal the
leg joints with heavy rubber boots and unless one is cut and breached your
seals will be pretty safe and dry.

on 02.6.21 0:56 PM, Ryan Gill at rmgill@mindspring.com scribbleth:
> Ground pressure is going to be far higher than a tracked vehicle.

Ground pressure is a key point. Probably require stompin' boots.

> I'd bet maintenance is worse than treads, and will probably remain

Even with full seals, the design either (1) has a large number of joints, one
for each degree of freedom on each leg or (2) has a complex joint with
multiple degrees of freedom. Treads are essentially glorified rollers, and
while you can drop a track, the tread mechanism itself is relatively tough
and adjustment-free, because it is constrained in a very
narrowly-defined
motion path, with only two directions of travel both on the same axis. A leg
mechanism, no matter how they design it, is going to be a nightmare of
components with enormous fluctuations in loading. I'd love to be on the design
team, but I'd really, really hate to have to deliver one on a schedule.

> At 1:04 PM +0900 6/21/02, Edward Lipsett wrote:

Rollers with lots of moving parts regardless.

> and adjustment-free, because it is constrained in a very
A leg
> mechanism, no matter how they design it, is going to be a nightmare of

Well, the difference is that the treads are very good at getting their parts
all gummed up with muck, dirt, and other things that aren't friendly to
bearings. Each track has road wheels, springs and other items that all have
bearings and seals to pay attention to. The tracks themselves are also an
issue unless you have rubber band tracks. Lots of things to maintain. Lots of
grease nipples. I can see building a very well protected housing around each
leg of a walker and making it all a sealed system that is much harder to get
crud into that will cause problems with the bearings in the first place. 3
layers of seals would be much better.

We sound like two blink men discussing an elephant <g>. I think we're pretty
much saying the same thing, actually: MTTF sucks regardless.

I hope someone builds one anyway, so there!

on 02.6.21 1:54 PM, Ryan Gill at rmgill@mindspring.com scribbleth:
> Well, the difference is that the treads are very good at getting

Not to mention push the envelope of articulated movement technology, possibly
leading to really nifty, practical applications of said technology.

--Flak

> On Thu, 2002-06-20 at 01:21, K.H.Ranitzsch wrote: