"We think that having that capability when the steering wheel and the pedals are still in the vehicle is a very good way to demonstrate and prove the safety,” Barra told reporters before the company's annual meeting at its Detroit headquarters.
Alphabet Inc's Google has proposed doing away with the steering wheels in autonomous vehicles because once developed, they may not need them.
IHS Automotive on Tuesday issued a report that estimates that by 2035, there will be 21 million autonomous vehicles in the world.
Barra also praised GM's record profit in 2015 and reiterated that the company would be at the forefront in the evolution of the auto industry towards autonomous vehicles and ride-sharing. GM said its 2016 profit will be improved from last year's record.
During the meeting, Barra defended GM's emphasis on retail auto sales in the US market, which are direct sales to consumers, and its de-emphasis on low-profit sales to rental agencies. The practice has led to fewer overall sales.
GM's market share has slipped to 16.6 percent in the first five months of this year compared with 17.7 percent for the same period in 2015. "All share is not created equal," Barra said.
She also noted the company's purchase of San Francisco- based Cruise Automation, for a reported US$500 million, as proof of its progress toward autonomous vehicles. Cruise, she said, has "deep software talent and rapid development capability."
Shareholders on Tuesday approved a slate of a dozen for the No. 1 US automaker's board of directors, including Barra, who also chairs that board.
One new member, Jane Mendillo, 57, former president and chief executive officer of Harvard Management Company, which manages the endowment of Harvard University, was voted to the board. She replaces outgoing board member Steve Girsky, who joined the board in 2009 and did not seek re-election.
