I've tried a few different times to build my own version of this but can never seem to make it work usually becuase of the wheels pulling inwards when it moves forward. does anyone have know site with instructions for building one? already searched mocpages and brickshelf and I've seen a few examples but can see enough of the steering assembly to recreate it myself.

how big do you want to build?

Mahjqa (a.k.a. Mahj) posted a Flickr photostream of his impressive Batman "Tumbler" made from Lego Technic elements. The car was featured on the "Batman Begins" movie. There are 7 additional photos of the MOC on his Brickshelf gallery. The Tumbler's front steering yoke is certainly distinctive, and it is very quick and nimble. Mahjqa wrote, "To those unaware; this is something I built myself. It's not available in stores, and there's no instructions available. Due to technical difficulties I'm going to have to rebuild this thing." If you view the end of the YouTube video, you'll know why:

"The Tumbler, with functional steering, driven with Power Functions. It's not entirely done yet, as I'm not really absolutely happy with some of the details. The panels in front of the windscreen are just weird, but they're weird in the original too. If you've got a better idea, let me know."

"Plenty of mechanics. From left to right: differential, two-speed gearbox, HUGE BATTERYBOX, steering system....I believe these tires match the look of the original quite well (they're from the 5571 Black Cat)":

"What I'm proudest of is the steering system; there's very few Lego tumblers with steering....It's not 100% movie accurate; detail had to be sacrificed to make the electronics fit inside":

how big do you want to build?

probably about the same size as the one DLuders probably a bit bigger cos I have lots large wheels. looks easy enough to recreate only thing I cant workout is what those grey pieces are right next to the wheels held in by light grey half pegs with sticks coming out either end. doesn't look like a pice I have anyway

On this Minipix blog, Matthew Dawkins ("MatthewMiniPix") explains in detail his Lego "Tumbler" car inspired by the "Batman Begins" movie. He wrote,

"Each front wheel has its own steering mechanism, comprised of a transverse rack-and-pinion system linked up to a custom wheel bearing joint. You can see a little of the mechanism in the photo below. Not only do you have hardly any room in which to put all that mechanism, but it also has to be solid enough to support the weight of the rest of the vehicle. With the offset of the wheel and the looseness in the bearing I actually had a problem with the camber of the wheels. To resolve that I had to put some spacing at the top, effectively angling the whole wheel downwards to counteract the camber.

"Alongside the complications of steering, the suspension system used in the Tumbler is quite unusual. The wheel sits at the end of an arm, which pivots at its connection with the rest of the subframe, and it held in place by two small springs for extra rigidity. The placement of those springs actually means a lot of spring force is needed, hence two springs on each arm rather than two; it’s all to do with turning forces and suchlike – the springs would have been more effective at a different angle, but then they wouldn’t look right. Thankfully they just about do the job ok."

The first YouTube video shows the "Working chassis for a Lego Technic model of the 'Tumbler' from the movie 'Batman Begins'. Work in progress, but this video shows the suspension working on all four wheels, and real working steering on the front! I had to invent my own mechanism for that, using transverse rack-and-pinion systems on each arm to steer each wheel. It's all linked together and you steer from the back using what will eventually be the rocket booster!

"Still got lots to do, so might post a follow-up later. The next technical challenge will be the canopy opening, which again I'm going to try to make as accurate as possible, technically-speaking. Then it's just a case of dressing it up appropriately and using up all my black pieces..."

http://www.youtube.com/watch?v=4WWpRUPfXxg

The

shows the completed "Tumbler model based on the batmobile from 'Batman Begins', made entirely from Lego. Has working steering and suspension. See http://www.minipix.co.uk for more details."

probably about the same size as the one DLuders probably a bit bigger cos I have lots large wheels. looks easy enough to recreate only thing I cant workout is what those grey pieces are right next to the wheels held in by light grey half pegs with sticks coming out either end. doesn't look like a pice I have anyway

that is a cross with a crossaxle hole in the middle. the cross is fixed in the chassis with two 1/2 pins.

I don't how I can help you with words but I figured I would post a picture of a MOC I have not yet released.

Each steering arm has independent suspension. The only problem with my setup is that the entire vehicle weighs so much that, occasionally, the front wheels (being plastic instead of rubber) will slip and the car will not turn as much..

Is it possible to stick something onto the wheels? Some thin layer of rubber or other anti-skid substance?