Friday, January 25, 2008
Young Carlisle engineer drives new technology
"Pushing the envelope" barely begins to describe Tully Foote's contribution to the development of driverless cars. Driverless cars, you ask? Yes — not tomorrow, perhaps not until 2015, but definitely on the horizon, and Tully is in the forefront of the technology.
Tully, 24, a Carlisle native, has been involved in this technology for six years, starting as a freshman mechanical engineering student at Cal Tech where he earned his undergraduate degree, and continuing at the University of Pennsylvania where he has just completed his master's in mechanical engineering. He went to the Carlisle Public School through fourth grade, then to the Fenn School and Concord Academy, where he graduated in 2002.
In the November 2007 DARPA Urban Challenge, Tully's 12-member team from the University of Pennsylvania/Lehigh College converted a Toyota Prius to an autonomous vehicle. The car, called "Little Ben" after the team name "Ben Franklin Racing Team," finished fourth out of eleven starters. Only six cars finished the course. "Ben's" feat seemed even more remarkable after we spoke with Tully's parents, Lisa and George Foote, at their home on Judy Farm Road.
A two-track competition
The concept of "Ben" as underdog emerged when George Foote explained the structure of the DARPA program. "The first two challenges, in 2004 and 2005, were entirely unfunded," he said, with $1 million going to the winner in 2004, and $2 million in 2005. "There were no second or third prizes." For the 2007 competition, DARPA created two tracks — Track A awarded funding up to $1 million to eleven teams (out of 65 proposals), while "Track B teams were self-funded in the hope they might win a prize at the end of the day," George explained. The two tracks competed equally. His son's team was the only Track B team to finish the competition. The first-place winner, Carnegie Mellon's "Boss," was a Chevy Tahoe SUV developed by the university's Robotics Institute with the backing of General Motors and a number of major software developers — quite a powerful pedigree.
George described the process that led to the Urban Challenge. "Qualifiers were held to determine what vehicles were most likely to successfully complete the Challenge. The vehicles' capabilities were tested, not their speed, which is not a criterion in any part of the program." He went on to explain that the vehicle has to make decisions based on what it "sees." It is not pre-programmed nor controlled from the outside. "It's given a set of rules by which it must make decisions as events unfold," he said.
The "unfolding events" could be a boulder in the middle of the road or a car (with driver) approaching from an intersection. The vehicle must make a decision to go around or avoid the obstacle, and therein lies the heart of the competition: "the key piece is that they have to be able to make "intelligent" decisions," in real time, George emphasized.
Course simulates urban environment
While the two previous competitions were held in the Mojave Desert, DARPA created an artificial city for the 2007 Challenge at an abandoned U.S. Air Force Base in Victorville, California. The course covered 60 miles and had to be completed in less than six hours. The autonomous cars shared roads with 30 human drivers (wearing crash helmets) in conventional cars. DARPA organizers gave different routes to each vehicle so they would not just follow one another. The cars were given three different tasks, one after another.
"The course is described by a series of GPS [global positioning system] way points," said Lisa . "The only information the car has is the way point to tell it where to go."
An emergency stop button
George interjects: "The Urban Challenge included all the things you encounter when you drive to Concord or around Boston. The vehicles have to be able to come to a four-way stop and decide who's going to go in the proper order, make a left turn into traffic, pass — those are key elements." In the final event, every vehicle has a chase car behind it with a human operator. The chase car has only one control — the stop button in case of emergency.
The Footes were in Victorville for most of the qualifiers and the final. From a bleacher area they could see the cars start, and cameras and projection screens allowed spectators to view the course, "but poorly." "What was so amazing about the whole process was to watch the teams work," said Lisa. "They were constantly adjusting and trying to optimize their cars. Just watching the teamwork and the way they problem-solved was remarkable."
Why the Prius?
The Ben Franklin Racing Team chose the Prius because, as a hybrid, it has a large electrical system already built into it, George explained. "You don't have to create one to run the computers. The goal is not to build a vehicle; you get as much off-the-shelf stuff as you can." He noted that for most of the development phase, Tully's team had virtually no university support or funding. They couldn't afford a valuable car, and the Prius was parked on the street. Tully took the rotating sensor — a $75,000 device — off the roof rack at night to keep it safe.
In contrast, the Carnegie Mellon car that won was "a very hot car — very fast," custom-built by General Motors. Lisa points out that although speed was not the only objective of the Challenge — 30 miles per hour was the top speed this year, and 22 was average — in the final analysis it was speed that won for Carnegie Mellon. Her husband adds, "There were no students on their team. They have a huge Robotic Institute with a huge campus where they could test their vehicle." For "Ben" to have competed successfully against "bigger, well-funded, flashier teams is a remarkable achievement," reported Wired, the online magazine.
Another well-funded competitor was Stanford University's "Junior," a VW Passat, which was awarded $1 million for its second-place finish. Virginia Tech's Ford Escape hybrid, "Olin," took third and won $500,000. Tully's Ben Franklin Racing Team was fourth, followed by MIT and Cornell.
Contacted by e-mail, Tully wrote, "The Urban Challenge has been a great experience for me. I started out as a freshman mechanical engineer designing and building sensor mounts. Each year I learned new skills and took on new responsibilities. In the end I was the most senior mechanical member of the team, advising [on] everything mechanical on the vehicle as well as branching out into sensor data processing and overall system design." The sensor mounts he refers to consist of 64 lasers atop the Prius that sweep around in a circle to see what's there and send signals back to a computer. Five of the six finishers in the Urban Challenge used this sensor.
The Footes are justifiably proud of their son's achievements. "Tully has a very broad set of skills," said his mom. "He has his degree in mechanical engineering, but he still understands how the software works and can write it." George adds that his son is also a helicopter pilot, who started his training during his junior year in high school.
Tully continued, "With the skills that I've developed through the Grand Challenges I've just been hired by Willow Garage of Menlo Park [California] and started last week. I'm going to keep pushing the envelope there not only on autonomous cars but also boats and personal robots capable of doing household chores."
When driverless cars and personal robots begin showing up in Carlisle sometime in the next decade, you can be sure that Tully Foote's expertise helped make them possible.
© 2008 The Carlisle Mosquito