Carnegie Mellon University spinoff targets traffic flow

Surtrac, INC. CEO Greg Barlow shows off his company's inteligent and adaptive traffic signal technology Wednesday November 13, 2013 in his office at Carnegie Mellon University.
Surtrac, INC. CEO Greg Barlow shows off his company's inteligent and adaptive traffic signal technology Wednesday November 13, 2013 in his office at Carnegie Mellon University.
Photo by James Knox | Pittsburgh Tribune-Review
| Wednesday, Nov. 13, 2013, 11:42 p.m.

Traffic changes constantly in cities and only worsens, says Greg Barlow, whose company Surtrac Inc. developed a system to improve flow and reduce stops.

He claims an overall 25.8 percent travel-time improvement in tests in East Liberty, and said on Wednesday that Pittsburgh Public Works officials want to see it proved over a longer period.

“Pittsburgh is willing to try new things and be part of innovation,” said Barlow, who intends to incorporate the Carnegie Mellon University spinoff whose computer system improves not only travel times but speed and waits at lights. A bonus, he said: reduced emissions.

“There are 300,000 traffic signals in the United States, and most of them don't work very well,” said Barlow.

Surtrac was one of six startups highlighted at Launch-CMU, an event sponsored by the university's Center for Innovation and Entrepreneurship to showcase research and innovation by students, alumni, faculty and staff.

Carnegie Mellon President Subra Suresh said the Oakland-based school created 36 companies this year, the highest number in its history.

“These give you a feel for the entrepreneurial culture at this place,” he said.

Surtrac installed equipment at nine intersections around Penn Circle in June 2012, and nine along Penn Avenue near Bakery Square this year. It intends to have 49 in the city in 2015.

“Every intersection has a computer and network that optimizes the traffic flow,” said Barlow, a project scientist who earned a doctorate from Carnegie Mellon. His co-workers are Steve Smith of Carnegie Mellon's Robotics Institute and Xiao-Feng Xie.

The Surtac system can use any type of sensor to count vehicles and determine speed, including in-pavement sensors, video and increasingly, radar.

“It runs optimizations constantly, handles disruptions such as a bus pulling over or accidents, and can respond second-to-second,” Barlow said.

Yet most drivers would be unaware of it — and that's the way it should be, so they can concentrate on driving, he said.

Carnegie Mellon faculty and students have spun out more than 130 companies over the past five years and attracted $400 million of investment, the university said. Surtrac raised nearly $2 million from the Hillman Foundation, the Heinz Endowments, the R.K. Mellon Foundation and an unnamed source.

The advantage of Surtrac's technology is that it coordinates flows for many directions of travel, Barlow said. Most adaptive traffic systems on the market are designed to handle straight-line corridor traffic not in urban areas.

Surtrac's equipment costs about $20,000 per intersection and can be installed in a day, without modification to equipment or roads.

Tests in the Penn Circle area measured performance on 12 routes during four periods of the day, using GPS tracking. Travel time improved, ranging from 32.8 percent at midday to 17.5 percent in the evening. Stops were reduced by 52.6 percent at midday, 29.1 percent during morning rush, and 34.9 percent in the evening commute. Wait times dropped 47.8 percent during mornings and 35.6 percent during evenings.

The system operates independently at each intersection but is on a network that communicates with other units. If one goes down, others nearby still operate.

“In traffic, there's always sources of uncertainty,” Barlow said. “You have to be able to deal with the real world.”

PennDOT last year used similar technology at eight intersections in a $21 million project to improve a 2.3-mile stretch of Route 19 in McCandless and Pine.

John D. Oravecz is a Trib Total Media staff writer. Reach him at 412-320-7882 or

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