A Nutonomy self-driving car has already been publicly tested in Singapore. (Nutonomy)

Silicon Valley's steady march toward self-driving cars took another step forward Friday as the ride-hailing company Lyft said its customers will be able to summon a driverless vehicle on some roads by the end of the year.

The autonomy program, which is expected to launch in Boston before eventually spreading to other cities, could ultimately involve hundreds of thousands of vehicles, said company officials. Depending on the precise conditions of a trip — including the route, traffic, weather and time of day — riders who opt into the trial may be automatically picked up in a self-driving car built by one of a number of manufacturers working with Lyft, rather than a human driver.

“You're going to see it. You're going to see these vehicles on the street,” said Taggart Matthiesen, Lyft's senior director of product.

As with other companies that have been publicly testing self-driving cars, Lyft riders who participate in the program will be accompanied by test drivers sitting in the front seats of the vehicles.

The moves reflect Lyft's most visible push yet into the world of autonomy, which has so far been dominated by traditional automakers, such as Ford and General Motors, as well as tech giants such as Waymo and Uber, Lyft's biggest rival in the ride-hailing space.

Rather than trying to catch up to those firms by building vehicles of its own, Lyft's focus is on designing a common software interface that automakers can use to put their cars on the road and interact with the public. The effort is part of a larger self-driving car division that Lyft is launching in order to capitalize on an increasingly competitive technology market.

“We're building a way for third parties to plug their self-driving cars into our network,” said Luc Vincent, vice president of engineering at Lyft.

In Boston, that will mean riders could be ferried about in vehicles built by Cambridge-based Nutonomy. The so-called Open Platform, which Lyft announced in June, could feature vehicles from other partners as well, such as GM and Jaguar Land Rover, which entered into a deal with Lyft last month. The result may be a mishmash of autonomous vehicles serving Lyft riders in various markets across the country — an outcome, the company said, that will accelerate the development of self-driving technology.

As Lyft's partners begin picking up passengers and accounting for a portion of the 100 million miles covered monthly by human Lyft drivers, the cars' sensors will be collecting information on their surroundings that will gradually contribute to a centralized repository of data controlled by Lyft, Vincent said. Insights derived from studying that data can then be shared with the partner automakers. Individual manufacturers may retain the data collected by their own vehicles, but Lyft declined to say whether, for example, Waymo will be able to study data collected by Nutonomy's vehicles and vice versa. It is also unclear how much, if any, revenue the autonomous carmakers will receive from Lyft when their vehicles successfully complete a ride.

Although Lyft has left much of the vehicle development to its partners, it will still build sensor packages and other hardware on a limited basis. To facilitate those efforts, Lyft said it will open a research facility in Palo Alto, Calif., later this year and hire hundreds of employees to work with other automakers there.

The company insisted that its human drivers will continue to play a role as Lyft ramps up its commitment to self-driving vehicles. Officials said that in the future, drivers may turn into assistants for elderly passengers, or become in-car baristas and concierges.

Rising competition in the self-driving car industry could prompt traditional automakers to establish their own roving fleets of autonomous vehicles. But Lyft is betting that by being one of the first, it can gain an early foothold and become so dominant that car companies will continue to work with it, or seek to buy it out.

"Ultimately, that's the long-term play for Lyft," said Karl Brauer, an analyst at Kelley Blue Book. "They'll still want [Lyft] to jumpstart their network of users that'll be using the self-driving cars."

Self-driving cars are expected to play a key role in the future of transportation, according to tech and automotive executives. The technology may not only prevent the 95 percent of traffic accidents that are caused by human error, analysts say, but could also make commuters more productive and turn stagnant parking lots into more useful types of development. And as more Americans grow accustomed to ride-hailing and car sharing, even private vehicle ownership could see a decline in favor of intelligent public transit.

But autonomous cars also face conceptual and regulatory obstacles. A patchwork of state regulations currently governs how companies may test the technology. Some industry officials fear that a lack of uniform rules and expectations could hinder the development of self-driving cars by effectively preventing vehicles from crossing state lines.

On Wednesday, members of a key House subcommittee unanimously approved a bill that could establish the first federal laws governing self-driving cars. The full committee could hear the bill in time for Congress's August recess.

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