Shared rides — such as are offered by Lyft’s Lyft Line and Uber’s Uber Pool — are likely the first step to getting riders to accept future automated vehicles, representatives of those on-demand services said at the second day of the Automated Vehicles Symposium in San Francisco.

Joseph Okpaku, vice president of government operations for Lyft, said Lyft Line is available in 60 cities worldwide. In those cities, 20 percent of Lyft rides are shared rides, and some places, such as San Francisco, are much higher, verging on 50 to 60 percent.

Describing the company as “bullish” on automated vehicles, Okpaku said in five years, most of the company’s rides will be in automated vehicles, at least in urban core areas.

Adam Gromis, global lead on sustainability and environmental impact at Uber, agreed that the road to automated vehicles is paved with ride sharing, and said there are one billion vehicles on the planet, which are in use for only 5 percent of their lives — “that’s a lot of empty seats driving around.”

He said Uber is tapping into its data to help design future self-driving technology.

“We’re mapping cities … learning how people take trips,” which will help get them ready for automated vehicles, he said.

Uber and Lyft appeared on a panel along with Jeff Hobson, deputy director for planning for the San Francisco County Transportation Authority. He said the city plans to use development on Treasure Island, home to a former military facility, as a proving ground for a ride-sharing system.

The island, home now to just a few thousand residents, will grow to tens of thousands of residents in coming years, who would overwhelm the Bay Bridge if they all drove. The city will instead use some grant money as part of the Smart Cities initiative to install an automated shuttle.

Even before automated vehicles become widespread, trucks that are automated to some degree will likely be on the roads, according to speakers on another panel. Volvo has done demonstrations for truck platooning, where a lead truck can partially control another, or even several others, and the California startup Peloton Technologies is devoted entirely to the concept.

Josh Switkes, founder and CEO of Peloton Technologies, was asked if platooning will be commonplace by 2030, and instead predicted it will be prevalent long before that.

Alden Woodrow, product lead for self-driving trucks for Uber Advanced Technologies Group, agreed, and said, “we are hiring. The more talented people we can hire, the sooner we will get there.”