This is an idea that came to me in high school, but it took BJS' idea (below) to remind me of it.

Take any rear-drive truck or body-on-frame car that has a solid rear axle. Remove all the suspension and weld the axle directly onto the bottom of the frame, and add two idler wheels on a dead axle up front, also welded to the chassis.

Now add sets of pivoting wheels along the bottom to act as suspension, and wrap them all in rubber or steel tank treads. Then create two separate brake circuits to steer the vehicle, and you have yourself a tank! Of course, adding the armour and gun turret is up to you.

I'm sure that someone has done this, but I'm not sure how many have actually done it the way that a tank works.
-- discontinuuity, Jan 18 2007

Tank treads http://static.flick...32_417dab14ac_m.jpg
This gives a good view of a drive wheel at the back, an idler wheel at the front, and suspension wheels in pairs in the middle. [discontinuuity, Jan 18 2007]

Mattracks http://www.gizmodo....h-tracks-220648.php
Similar idea, but less perminent and with four separate treads. [discontinuuity, Jan 18 2007]

Thank you.
-- BJS, Jan 18 2007


I WANT ONE!
-- MoreCowbell, Jan 18 2007


I've wanted exactly that for twenty years, ever since waiting five minutes for a hen's tooth parking space with my turn signal on, only to have someone zip into it from the other side. The slightly lowered BMW 2002ti I was driving at the time wasn't really suited to parking on top of other cars
-- Ned_Ludd, Jan 18 2007


I can't see BJS' idea so I flagged it.
-- caspian, Jan 30 2007


I deleted it... but I can make it up again if anyone wants me to.
-- BJS, Jan 30 2007


Do tank treads grind up the road or ground when turning?

[BJS] Well not having read it I don't know why you deleted it. But if it fit the rules, yeah, repost it, otherwise maybe just briefly say here what it was.
-- caspian, Feb 02 2007


Yes, [caspian], I think they would. Unless it was only rubber that touched the ground, in which case it would just make screaching noises and wear down the rubber while turning. At least, that's what I see happen when construction equipment like Bobcats try to drive on pavement, since the wheels on each side always turn at the same speed.
-- discontinuuity, Feb 02 2007


Well, I've given it a bun even though I think the turning thing might make it a bit impractical, since it's fun, and after all, this is the halfbakery. Another question: how would it be going over potholes? Would the suspension wheels bump it like regular car wheels even through the track, or would it be much smoother?
-- caspian, Feb 03 2007


With pairs of suspension wheels rocking on a central pivot (see first link), the treads would essentially "roll" over obstacles, so going over potholes would be fairly smooth. I imagine this design would be best suited for off-roading, though.

By the way, is there a better category for this idea?
-- discontinuuity, Mar 16 2007


Remember that treads have a significantly lower ground pressure than a tire does. You have to divide vehicle weight over the entire area of the tread.
-- jhomrighaus, Mar 16 2007



random, halfbakery