"Over the course of this trial, we'll be accepting hundreds of people with diverse backgrounds and transportation needs who want to ride in and give feedback about Waymo's self-driving cars," said John Krafcik, Waymo CEO. "Rather than offering people one or two rides, the goal of this program is to give participants access to our fleet every day, at any time, to go anywhere within an area that's about twice the size of San Francisco."

To cater for this drastic increase in passengers, Waymo is increasing the size of its fleet. Right now, the company has 100 autonomous Chrysler Pacifica Hybrid minivans, but that number will rise to 600 in the coming months. The idea is to see where people want to go, but also monitor how families interact with the cars and assess what features they'd like to see inside them.

Waymo needs just one person from each household to apply, and if they're accepted, all members of their family will become part of the early rider program. Waymo has been careful not to put limits on the service either, adding that it encourages riders to use its vehicles "as frequently as possible." To that end, the company won't ask for any money, all rides will be free.