Over the last year, the DARPA Grand Challenge has been one of the most widely discussed and speculated about of all of the robotics competitions. As engineering professionals and competitors in other autonomous robotics competitions, we decided to go to L.A. to watch the event.
The first five days of the competition consist of qualification rounds on a man-made obstacle course. Each team gets at least two chances to attempt the course. On Saturday, the qualified teams will go to Barstow for the actual off-road race.
California Motor Speedway - Fontana, CA. An ideal location for the qualifying rounds of the competition. The weather was sunny, hot, and dry. The facility is surrounded by breathtaking vistas of snow-topped peaks.
The entrance tunnel leads to the Interior Road Course where the vehicles are serviced and tested.
This vehicle has an imposing look to it. Solid metal panels cover the vehicle where you would expect to see glass windows and windshield. I saw this one driving around and I can easily envision this thing patrolling deserts on overseas deployment.
If I were to design a vehicle for the Grand Challenge, it would probably look similar to this one. I like the idea of starting with a mid-sized truck or SUV with four-wheel drive. Then the vehicle is fitted with actuators that enable the vehicle to be driven under computer control. Add a robust sensor suite and computers that run the mission control software and you're basically ready to start road tests. If needed, upgrade with an off-road suspension kit and an extra fuel tank so the truck can go the distance: 200 miles through the Mojave desert. It looks like about half of the teams at the competition have taken this sort of approach in designing the mechanical platform of their robots.
In contrast to the approach of modifying a stock SUV preferred by several of the teams, Terrahawk has a custom build mechanical frame and drivetrain. The chassis is composed of three articulated sections, each with two wheels. The suspension on each wheel is independently adjustable to help navigate the rough desert terrain. Terrahawk probably has the highest ground clearance of all the entries. I think the strategy is to not spend too much effort detecting and avoiding smaller obstacles because the robot can simply crawl over them. I can't wait to see this monster navigating the demonstration course.
High School??!! What's going on here? To build such a sophisticated Grand Challenge robot, these guys got 1337 5killz.
The Doom Buggy is a modified Acura MDX SUV. The design looks solid and very competitive. A pair of video cameras are mounted on each side of the winshield and there are ruggedized racks of computers in the stripped passenger/cargo area.
The Dexterit - Ghost Rider is the smallest vehicle at the Grand Challenge. It is also the only vehicle with just two wheels. All other vehicles have either four or six wheels. It is interesting that all of the entries competing in the grand challenge are wheeled vehicles. Tank treads have several advantages over wheels for a robotic vehicle: superior traction on many terrain types, no failures because of flat tires, and the ability to turn in place.
The Dexterit - Ghost Rider was built by modifying a dirt bike. It drives on only two wheels, no training wheels, and keeps itself balanced by steering the front wheel as it drives forward. It is questionable whether the possible improved terrain handling abilities a two-wheeler has over a four-wheeler could possibly justify the amount of effort it takes to build a self-balancing vehicle. This design also sacrifices the ability to stop and back up in order to avoid an obstacle. At the Grand Challenge the Dexterit - Ghost Rider has demonstrated the ability to drive upright for short distances.
Just look at this one. Weighing in at 23,000 pounds, this behemoth dwarfs all of the other vehicles, and just about anything else! The Terramax is a six-wheel drive truck with power to spare making it a real crowd-pleaser. It has made several runs on the Grand Challenge QID (Qualification, Inspection, and Demonstration) course. It navigates the course briskly and accurately, and has completed the first third of the course before stopping on all of its runs. It generally avoids obstacles well, with the exception with its latest run. One of the obstacles is a minivan parked along the designated path, which the Terramax slammed into sending a shower of broken window glass from the minivan. The Terramax proceeded to push the van with ease for about ten feet before it decided to stop. The collision caused no apparent damage to the Terramax.
Sandstorm has an impressive suite of sensors with mounted on its top. Several of the instruments use spinning disks and twitching mirrors. Just two weeks ago, Sandstorm rolled over during an off-road test destroying a quarter of a million dollars of sensors. Since then, the team has been franticly working to repair the vehicle and replace the broken equipment.
The budget for the Red Team must be large: Boeing hired skywriters to cheer the team on during the qualifying runs. On the second day of the competition, Sandstorm completed the qualification course becoming the only team as of yet to qualify to attempt the Grand Challenge off-road racecourse through the Mojave Desert.
In the Caltech team's garage port they were busy preparing the vehicle. BOB has the second best qualification run so far, making it about 75% of the way around the obstacle course.