San Francisco (AFP) - The race to perfect robot cars continues despite fears kindled by the death of a woman hit by a self-driving Uber vehicle while pushing a bicycle across an Arizona street.

Uber put a temporary halt to its self-driving car program in the US after the fatal accident this month near Phoenix, where several other companies including Google-owned Waymo are testing such technology.

While the Uber accident may be used to advance arguments of those fearful of driverless cars, it does not change the fact that "transformative technology is coming whether we like it or not," according to Adie Tomer, a fellow at the Brookings Institution think tank in Washington.

"There certainly will be calls to stop all autonomous vehicle testing, not just Uber's program," Tomer said in a post on the institution's website.

"But, technological progress is hard to stop, and I don't expect it to happen in this case."