The digital display mounted over Interstate 376, four miles before the Squirrel Hill Tunnel, warns drivers in bright-orange letters how long they will wait in traffic.

On this afternoon, it takes four minutes. But if there is congestion or a crash ahead, technicians at the Western Regional Traffic Management Center in Bridgeville can instantly update the system, warning drivers if they should detour.

The center opened in 1998. Since then, the melding of transportation and technology has increased exponentially, according to experts who will gather in Pittsburgh this week for the Intelligent Transportation Society America conference for its 25th Annual Meeting.

“What we’re seeing is a converging between the interstate highway system and the information superhighway,” said Paul Feenstra, senior vice president with ITS America. “The industry and ITS America’s membership over the past five years have really evolved to reflect the critical role technology has to play in today’s transportation infrastructure.”

The organization’s membership includes traditional highway interests such as General Motors, Ford and state transportation departments, and the likes of Apple, Google and Verizon.

The four-day conference of panels and demonstrations in the David L. Lawrence Convention Center spans data analytics, driverless cars and high-tech start-ups. Chris Urmson, who heads self-driving car research at Google, will deliver the opening keynote address Monday. Corey Owens, head of global public policy at the ride-share company Uber Technologies, will give the closing address Wednesday. Attendance is expected to be about 2,000.

The field of so-called “smart transportation” has evolved beyond the kind of dynamic messaging systems PennDOT operates in Western Pennsylvania, including 41 in Allegheny County, said Mark Joseph Magalotti, the co-director of the Center for Sustainable Transportation Infrastructure at the University of Pittsburgh. Overall, the goal of intelligent transportation is to address safety and traffic issues on roads using cost-effective technology.

“At some point, somebody realized there were only so many highways we can build,” he said.

The technology, such as adaptive traffic signals, requires a brain trust of data analysts and robotics engineers, along with those who have backgrounds in transportation planning.

“As an engineer, you tend to think about a problem in a certain way,” Magalotti said, “where someone who has a programming background might think about a different approach.”

Jim Barbaresso, who directs intelligent transportation programs at engineering and consulting firm HNTB Corporation, helped debut the first adaptive traffic signals in the Detroit area in the early 1990s through a federal program. He sees the next frontier as cars that are equipped with sensors to know when they’re too close to each other and brake automatically.

At the ITS conference, a limited 40-person audience will witness a demonstration of Carnegie Mellon University’s driverless car, an autonomous 2011 Cadillac SRX.

“What we’re seeing is a transformation of our transportation system that is being driven by automation and connectivity,” Barbaresso said.