A giant robotic hand holds up the remains of a vehicle crushed by a lucky member of the Robodock 2007 audience. View Slideshow AMSTERDAM – A giant mechanical hand sits amid a litter of destroyed automobiles in an abandoned shipyard here.

At last month's Robodock festival, untrained volunteers used the complex technological work of art to pick up and crush shopping carts, cars and even a small van. Soon, the huge robotic hand might be sold for scrap metal, a perfectly normal death for a piece brought to life at the annual Amsterdam art fest.

The hand in question is 25 feet long, weighs 5,000 pounds and was built in just 12 days entirely out of scrap and recycled parts by the international team of Doyle Shuge, Justin Gray, Conrad Karlson and Jens Schendel, under the direction of veteran "machine performance" artist Christian Ristow of Robochrist Industries.

The fingers are segments of old I beams, the forearm is the modified truss of an ancient digging machine, and the entire hydraulic system was assembled from junkyard salvage. Plumbing and cables were ripped from the walls of the old shipbuilding warehouse where the hand was constructed. (Disclosure: I helped with some of the wiring on the project for an afternoon.)

Anybody can crush big things with the giant hand.

"When I first came to Robodock last year," says Ristow, "I decided that what was missing was audience interactivity, and violence."

During Robodock, Ristow waves to a young man standing in line. The lucky festivalgoer climbs the chain ladder to the operator's tower, inserts his hand into a custom control armature, and proceeds to pick up and crush an old Renault van.

The hand moves slowly, grindingly, making ominous groaning noises and dripping hydraulic fluid as its closing fist mangles the vehicle. The operator lifts the remains of the van 20 feet off the ground, gives it a final crunching squeeze as huge, rusty fingernails shatter the windshield, then drops it to the concrete. The crowd cheers wildly.

"That was awesome," says the man as he walks away from the robot and the carcass of the van. "Such a feeling of power!" He's got a weird grin on his face, but then it's not every day you can crush a car with your hand.

Meanwhile, Gray selects the next operator.

"OK, kids only tonight," he announces, and a great shout of glee goes up from the under-12 set.

See the giant hand in action about 30 seconds into this video clip from Robodock 2007.

The scene is pure Robodock. A group of squatters living at the abandoned ADeM docks in northern Amsterdam started the festival in 1998. Since then it has evolved into one of the premiere international exhibitions of underground machine, tech and performance art.

For its 10th anniversary this year, the festival featured everything from giant metal fire sculpture by the San Francisco-based Flaming Lotus Girls to Ben Blakebrough's homemade Hiller flying machine to the collaborative human-robotic symphony of France's La Machine.

The festival's squatter roots favor a scrap-metal aesthetic and the use of recycled, salvaged or otherwise "found" materials.

"This is low-tech art produced by high-tech minds," says Ristow.

Now that the festival is over, Ristow would prefer to take his robotic hand back to the United States for further shows, but it's expensive to move and store such a large and heavy object. Instead, if no buyer is found, the piece will be scrapped, cut apart and sold back to the junkyard.

It would be a sad fate, but Ristow says he would feel fine about it. After all, that would be in keeping with the Robodock tradition.

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