DARPA Grand Challenge

The DARPA Grand Challenge is a prize competition for driverless cars, sponsored by the Defense Advanced Research Projects Agency (DARPA), the most prominent research organization of the United States Department of Defense. Congress has authorized DARPA to award cash prizes to further DARPA’s mission to sponsor revolutionary, high-payoff research that bridges the gap between fundamental discoveries and their use for national security. DARPA has technologies needed to create the first fully autonomous ground vehicles capable of completing a substantial off-road course within a limited time. The third event, The DARPA Urban Challenge, which took place on November 3, 2007 and was broadcast via webcast, further advanced vehicle requirements to include autonomous operation in a mock urban environment.

History and Background

Fully autonomous vehicles have been an international pursuit for many years, from endeavors in Japan (starting in 1977), Germany (Ernst Dickmanns and VaMP), Italy (the ARGO Project), the European Union (EUREKA Prometheus Project), the United States of America, and other countries.

The Grand Challenge was the first long distance competition for driverless cars in the world; other research efforts in the field of Driverless cars take a more traditional commercial or academic approach. The U.S. Congress authorized DARPA to offer prize money ($1 million) for the first Grand Challenge to facilitate robotic development, with the ultimate goal of making one-third of ground military forces autonomous by 2015. Following the 2004 event, Dr. Tony Tether, the director of DARPA, announced that the prize money had been increased to $2 million for the next event, which was claimed on October 9, 2005. The first, second and third places in the 2007 Urban Challenge received $2 million, $1 million, and $500,000, respectively.

The competition was open to teams and organizations from around the world, as long as there were at least one U.S. citizen on the roster. Teams have participated from high schools, universities, businesses and other organizations. More than 100 teams registered in the first year, bringing a wide variety of technological skills to the race. In the second year, 195 teams from 36 US states and 4 foreign countries entered the race.

2004 Grand Challenge

The first competition of the DARPA Grand Challenge was held in 2004 in the Mojave Desert region of the United States, along a route that follows along the path of Interstate 15 from just before Barstow, California to just past the California-Nevada border in Primm. None of the robot vehicles finished the route. Carnegie Mellon University's Red Team traveled the farthest distance, completing 11.78 km (7.36 miles) of the course.

2005 Grand Challenge

The second competition of the DARPA Grand Challenge began at 6:40am on October 8, 2005. All but one of the 23 finalists in the 2005 race surpassed the 11.78 km (7.36 mile) distance completed by the best vehicle in the 2004 race. Five vehicles successfully completed the race:

Vehicle	Team Name	Team Home	Time Taken (h:m)	Result
Stanley	Stanford Racing Team	Stanford University, Palo Alto, California	6:54	First place
Sandstorm	Red Team	Carnegie Mellon University, Pittsburgh, Pennsylvania	7:05	Second place
H1ghlander	Red Team Too		7:14	Third place
Kat-5	Team Gray	The Gray Insurance Company, Metairie, Louisiana	7:30	Fourth place
TerraMax	Team TerraMax	Oshkosh Truck Corporation, Oshkosh, Wisconsin	12:51	Over 10 hour limit, fifth place

Vehicles in the 2005 race passed through three narrow tunnels and negotiated more than 100 sharp left and right turns. The race concluded through Beer Bottle Pass, a winding mountain pass with sheer drop-offs on both sides. Although the 2004 course required more elevation gain and some very sharp switchbacks (Daggett Ridge) were required near the beginning of the route, the course had far fewer curves and generally wider roads than the 2004 course.

The natural rivalry between the teams from Stanford and Carnegie Mellon (Sebastian Thrun, head of the Stanford team was previously a faculty member at Carnegie Mellon and colleague of Red Whittaker, head of the CMU team) was played out during the race. Mechanical problems plagued H1ghlander before it was passed by Stanley. Gray Team’s entry was a miracle in itself, as the team from the suburbs of New Orleans was caught in Hurricane Katrina a few short weeks before the race. The fourth finisher, Terramax, a 30,000 pound entry from Oshkosh Truck, finished on the second day. The huge truck spent the night idling on the course, and was particularly nimble in carefully picking its way down the narrow roads of Beer Bottle Pass.

2007 Urban Challenge

The third competition of the DARPA Grand Challenge, known as the "Urban Challenge", took place on November 3, 2007 at the site of the now-closed George Air Force Base (currently used as Southern California Logistics Airport), in Victorville, California (Google map). The course involved a 96 km (60-mile) urban area course, to be completed in less than 6 hours. Rules included obeying all traffic regulations while negotiating with other traffic and obstacles and merging into traffic.

The $2 million winner was Tartan Racing, a collaborative effort by Carnegie Mellon University and General Motors Corporation, with their vehicle "Boss", a Chevy Tahoe. The second place finisher earning the $1 million prize was the Stanford Racing Team with their entry "Junior", a 2006 Volkswagen Passat. Coming in third place was team Victor Tango from Virginia Tech winning the $500,000 prize with their 2005 Ford Escape hybrid, "Odin". MIT placed 4th, with Cornell University and University of Pennsylvania/Lehigh University also completing the course.

The six teams that successfully finished the entire course:

Team Name	ID#	Vehicle	Type	Location	Time Taken (h:m:s)	Result
Tartan Racing	19	Boss	2007 Chevy Tahoe	Carnegie Mellon University, Pittsburgh, Pennsylvania	4:10:20	1st Place; averaged approximately 14 mph (22.53 km/h) throughout the course
Stanford Racing	03	Junior	2006 Volkswagen Passat Wagon	Stanford University, Palo Alto, California	4:29:28	2nd Place; averaged about 13.7 mph (22.05 km/h) throughout the course
VictorTango	32	Odin	2005 Ford Hybrid Escape	Virginia Tech, Blacksburg, Virginia	4:36:38	3rd Place; averaged slightly less than 13 mph (20.92 km/h) throughout the course
MIT	79	Talos	Land Rover LR3	MIT, Cambridge, Massachusetts	Approx. 6 hours	4th Place.
The Ben Franklin Racing Team	74	Little Ben	2006 Toyota Prius	University of Pennsylvania, Lehigh University, Philadelphia, Pennsylvania	No official time.	One of 6 teams to finish course
Cornell	26	Skynet	2007 Chevy Tahoe	Cornell University, Ithaca, New York	No official time.	One of 6 teams to finish course

While the 2004 and 2005 events were more physically challenging for the vehicles, the robots operated in isolation and only encountered other vehicles on the course when attempting to pass. The Urban Challenge required designers to build vehicles able to obey all traffic laws while they detect and avoid other robots on the course. This is a particular challenge for vehicle software, as vehicles must make "intelligent" decisions in real time based on the actions of other vehicles. Other than previous autonomous vehicle efforts that focused on structured situations such as highway driving with little interaction between the vehicles, this competition operated in a more cluttered urban environment and required the cars to perform sophisticated interactions with each other, such as maintaining precedence at a 4-way stop intersection.

Technology

For reference, see DARPA Urban Challenge, a C++ based platform for testing Path Planning Algorithms: An application of Game Theory and Neural Networks.

2007 Urban Challenge teams employed a variety of different software and hardware combinations for interpreting sensor data, planning, and execution. Some examples:

• Cornell's code is written in C++ and C# and runs on 17 dual core servers. Planning involves Bayesian mathematics.
• Insight Racing is using Mac Minis running Linux because they can run on DC power at relatively low wattage and produce less heat.
• Team Case is using Mac Minis running Windows.
• Team LUX is running an embedded version of Windows XP.
• Team Jefferson's software runs on Perrone Robotics' MAX robotics platform running atop Sun Microsystems' Java RTS on Solaris, Java SE on Linux, Java ME running on micro-controllers and SunSpots.
• Sting Racing's software is written in Java running on Linux.
• VictorTango's software is written in LabVIEW and is split between Windows and Linux servers.
• Team Gator Nation's architecture consisted of C, C++, and C# running on a variety of windows and fedora systems communication with the JAUS protocol.
• MIT's software is written in C, running on a Linux cluster with 40 cores.
• Austin Robot Technology's software software was written and developed by undergraduates from a UT-Austin course The code was in C++, using the Player Project as an infrastructure.

The winning entry, Tartan Racing employed a hierarchical control system, with layered mission planning, motion planning, behavior generation, perception, world modelling, and mechatronics.

VaMP (1995) compared to vehicles in the DARPA Grand Challenge (2005)

Five cars finished the course of the 2005 DARPA Grand Challenge: Stanley, Sandstorm, H1ghlander, TerraMax, and Kat-5. It is interesting to compare them to the earlier VaMP robot car of Mercedes-Benz and Ernst Dickmanns. The VaMP was built in the 1990s as a continuation of Dickmanns' earlier work at the Universität der Bundeswehr München in Munich; the project was funded in part by the $1 billion dollar EUREKA Prometheus Project. The VaMP was able to drive in traffic among moving obstacles, automatically passing slower vehicles; the DARPA cars were not (H1ghlander was standing still when Stanley passed it in the 2005 DARPA Grand Challenge) . The VaMP reached speeds up to 180 km/h (111 mph); the DARPA cars were limited to top speeds of 80 km/h (50 mph). In 1995, the VaMP drove up to 158 km without human intervention on a Danish highway where most drivers adhere to the 110km/h general speed limit and passing is rarely necessary; decisions made by the VaMP were checked for validity by a human safety pilot (the 158km represent the longest stretch of thousands of km of test runs, and the terrain was self-selected by the VaMP team). In 2005, the DARPA cars drove 212 km (132 miles) without human intervention on the Grand Challenge course selected by the race organizers. VaMP drove on the mostly straight Autobahn; the DARPA cars drove on a variety of graded dirt roads, including narrow and steep mountain passes. The VaMP drove mostly by vision with some input provided by radar but without GPS navigation; the DARPA cars heavily used GPS, always driving from one waypoint to the next (the DARPA course was unrehearsed by the teams but precisely given by almost 3000 waypoints, with several waypoints per curve). The DARPA cars combined other sensor data such as LIDAR, video cameras, and inertial guidance systems for better navigation in between waypoints, where road boundary identification was sometimes harder than on the Autobahn because of the unstructured terrain (Autobahn road boundaries are engineered to be easily visually observable but often partially hidden by trucks etc). The top speed of the VaMP's computer processors was 1000 times slower per dollar than those used in the DARPA vehicles.

External links

• The home page of the DARPA Grand Challenge
• Announcement of the 2007 Grand Challenge (PDF)

Press coverage

• NOVA: The Great Robot Race
• The Register: Final robot grunts picked for $1million DARPA race
• The Register: DARPA's Grand Challenge proves to be too grand
• CNN.com: Robots fail to complete Grand Challenge
• SFGate.com: Robot race suffers quick, ignoble end
• 2004 DARPA Grand Challenge Image Gallery
• Journal of Field Robotics, Special Issue on DARPA Grand Challenge, Part 1
• Journal of Field Robotics, Special Issue on DARPA Grand Challenge, Part 2
• Wired Magazine article on the DARPA Grand Challenge and Stanley
• Popular Mechanics article on the DARPA Grand Challenge
• Popular Science article on the DARPA Grand Challenge
• Scientific American article on the DARPA Grand Challenge

Some additional prizes sites

• International Mars Society's University Rover Challenge
• Virginia's V Prize for spaceflight breakthroughs
• Innocentive's technical challenges page
• X Prize Foundation
• America's Rocketry Challenge (for students)

References