Game On

Axion Racing's autonomous car runs on Linux and a PlayStation 3.

by / December 28, 2007

Would you believe that by combining Linux, a Sony PlayStation 3, some servers and an industrial air conditioner, you could make a robot? Bill Kehaly did, and thrice entered such a machine into the DARPA Grand Challenge, a race where dozens of robotic cars compete to navigate a racecourse without help from a human driver.

The story of Kehaly's involvement in the Grand Challenge begins in the vast expanse of the western Pacific Ocean where hundreds of small islands - Guam, Palau, the Marshall Islands and other small bits of paradise - make up the region known as Micronesia. It was here that Kehaly launched his latest in a string of entrepreneurial ventures - a Micronesian water bottling company.

Kehaly already had owned a San Francisco consulting firm, served as an adviser to Warner Bros., managed finances and logistics for, and invented a digital, pen-based statistics charting system used by numerous Major League Baseball teams. In 2003, while in Micronesia helping get Milo Water off the ground, Kehaly read a newspaper article about something called the DARPA Grand Challenge.

DARPA, the Defense Advanced Research Projects Agency, is the real-life counterpart to the Q Branch from James Bond films. The agency builds and tests all manner of strange and amazing devices, many of which never leave DARPA labs. Some, however, make their way into the world as military hardware, and occasionally, into everyday use.

When Kehaly read a newspaper blurb about the race, something clicked.

"I had been thinking of ways to try to market [Milo Water]," he recalled. "When I read the article, I thought, 'If I found a team, I could dress up my old Jeep to look like a Milo bottle and then have this water bottle drive itself through the Mojave Desert.'"

Never afraid to take a risk, Kehaly ran with the idea and started searching for a team of engineers who could help him build a water bottle on wheels that could pilot itself. At a DARPA autonomous racing conference, a team of University of San Diego alumni that had spent years building robots was looking for a leader. It just so happened Kehaly was there looking for a team.


Gentlemen, Start Your AI
The first DARPA Grand Challenge took place in 2004 amidst the rocks and sagebrush of the Mojave Desert. As an incentive for the racers, DARPA put up a $1 million prize for the winner. The designated racecourse was to begin outside of Barstow, Calif., roughly parallel to Interstate 15, for 142 miles to Primm, Nev. For Kehaly and his team - newly dubbed Axion Racing - the race to transform the Jeep into an Autobot was on.

Right away, it became apparent that one of the original ideas, turning the Jeep into a water bottle, wouldn't be feasible. Instead, the Axion team - many members of which had backgrounds in building fighting robots for reality TV shows, such as Robot Wars - gathered a heap of the necessary equipment to give the Jeep a brain of its own.

The vehicle was outfitted with four Dell servers running Linux and numerous cameras and detection systems to help it navigate the course's terrain, including an infrared camera, a 3-D LADAR (laser detecting and ranging) system - which can see grass, water, rocks, etc. - an RGB (red, green, blue) camera, which spots obstacles in the vehicles path and a Northrop Grumman INS (inertial navigator device)/GPS.

Four Intel Xeon processors served as the vehicle's brain, running everything from "sight" to the mechanical gas and brake system. If the Jeep applies the brake, the accelerator is automatically halted, whereas when the Jeep depresses the gas pedal, the brake is automatically released.

When race day finally arrived, Axion was among 15 teams that qualified. On March 13, 2004, the Axion team steeled itself as their cobbled-together robot prepared to race nearly 150 miles to Nevada. The starter waved the flag, and the race was on.

"We actually went negative miles," Kehaly recalled good-naturedly. "We ended up behind that starting line."

The race was a disaster. No team came anywhere near the finish line. A vehicle built by a team from Carnegie Mellon University traveled the greatest distance - a paltry seven and a half miles. Many teams and observers said the course was largely to blame. The terrain was, they claim, exceedingly harsh in the first few miles. Regardless, the $1 million prize went unclaimed. But DARPA would later announce another race for 2005, this time on a new course and $2 million for the winner.


2005 and Now
The 2005 race was a huge success compared to the year before. Several teams actually finished the race - the winner was Stanley, a vehicle built by a team from Stanford University. Stanley completed the race in just less than seven hours. Axion's Jeep, named Spirit, made it 66 miles before becoming bogged down in a sandy stretch, ultimately finishing seventh. Kehaly was pleased with the performance but felt Spirit needed more intelligence.

DARPA did not schedule a race in 2006. However, the agency announced an urban race for November 2007. This time, the cars would race on the streets of Victorville, Calif., instead of in the desert surrounding the city. Axion searched for a better brain for Spirit, and, in late 2006, it arrived in an unusual place - inside Sony's new gaming console, the PlayStation 3 (PS3). The Cell Processor, an extremely powerful new microprocessor developed jointly by Sony, IBM and Toshiba, powers the PS3. At about $600 for a 60 GB model, the PS3 was a very high-end processor for not much money. Axion had found their new brain, now they needed an operating system.

"As luck would have it, I recently stumbled upon Yellow Dog Linux [YDL] and figured we could convert one of our Dell servers into a hopped-up PS3 to do some processing," Kehaly said. "I checked with the team during our weekly conference call. My team is great at [artificial intelligence] and we bought a copy of YDL and installed it on a PS3."

YDL is an open source operating system designed by Terrasoft Solutions to run on IBM Cell systems like the PlayStation 3. Axion already had success with Linux in the past, so this PS3-YDL combination was a perfect fit. They fitted the PS3 on the Dell server rack already in Spirit and started preparing for November.

"I've been thinking about replacing our Dell servers with a cluster of PS3s," Kehaly said, amused that a gaming and movie machine might be the key to winning the race.

Giving credence to Kehaly's idea of moving to a PS3 cluster, recent reports from the gaming industry have shown the PlayStation 3 has a failure rate of 0.02 percent - in other words, an astoundingly reliable machine - perfect for the cramped, hot and dirty world inherent to auto racing.

In late October, Spirit seemed to perform well in the qualification event. The driverless Jeep was busy managing left turns through oncoming traffic, safely - and eerily - making the turns at the appropriate time. Some turns were close calls, but by and large, the robot appeared to be doing well. Unfortunately for the Axion team, however, DARPA judges eliminated the team from further competition. Axion, like 24 other teams, would not race in the main event - leaving just 11 teams to compete in November.

After the qualification event, Kehaly was understandably unhappy.

"I thought we did well," he said. "The judges thought otherwise." 

For more on the DARPA Grand Challenge, watch our special report on GTtv.

Chad Vander Veen

Chad Vander Veen is the former editor of FutureStructure.


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