The most remarkable thing about a ride in a robot car is how unremarkable it is.

It is definitely eerie to see the steering wheel turn by itself, the car brake and change lanes without human intervention. But just as with cruise control, it soon feels commonplace.

I've been covering autonomous driving for several years so I've taken lots of these rides - often carefully choreographed to show the cars to best advantage.

Five years ago, I perched nervously in the driver's seat of a self-driving Uber Ford Fusion in Pittsburgh, ready to take the wheel as it criss-crossed the city's notorious bridges. I chugged around the campus of Santa Clara University in a converted golf cart from Auro Robotics, and barrelled down 1-280 in a self-driving big-rig truck from Otto.

Alongside Zoox co-founder Jesse Levinson, who narrated the trip like a proud parent, I wound through narrow San Francisco streets in 2018. Scientists at Stanford, UC Berkeley and Nissan Research Centre told me how they are facilitating communication between robot cars and humans.

Wednesday's jaunt in Waymo's self-driving Jaguar I-Pace had no surprises. The car smoothly glided to a stop at intersections and signalled before turns. The closest thing to a hiccup was a slight jerkiness when it pulled over to drop off us faux ride-hailing passengers. The company confined our 20-minute test drive to the wide, relatively empty streets of the Sunset district, avoiding the hills and traffic elsewhere in the city, so the car didn't face any challenges. Ever Guardado, our safety driver, never needed to assume control, but did so once at my request just to demonstrate the tones the car sounds when a driver takes over.

Four years ago when I rode in an earlier-generation Waymo robot car at its testing site on a former military base in Merced County, Waymo staged several complex situations: a bicyclist pedalling alongside, a pedestrian wandering into the crosswalk, a car abruptly cutting off the robot car and boxes sprawling into the road. That robot car, which did not have a person behind the wheel, adapted quickly to all the tests thrown at it.

Waymo, an arm of Google parent Alphabet, now has the distinction of running San Francisco's first robot taxi service for the public, albeit with backup drivers behind the wheel and limits on how many folks it will accept into its testing program.

Fleets of robot taxis are how Waymo, Cruise, Zoox and other main contenders in the self-driving race hope to eventually recoup their investors' multibillion-dollar investments.

Why test robot taxis in San Francisco? "It's a major ride-hailing market with a lot of demand from residents," said spokeswoman Julianne McGoldrick. "And it's one of the toughest environments for driving - weather, traffic, road grade, cyclists."

In other words, if a robot car can make it here, it can make it anywhere. That's also the philosophy of several of Waymo's competitors, notably GM spinoff Cruise, whose white Chevy Bolts are a common sight on city streets.

Waymo is far along on robot taxis in Phoenix, a much easier city to navigate. It's given rides to selected testers since 2017, jettisoned the backup drivers since 2019 and now, for almost a year, has been giving hundreds of fully autonomous paid rides - sans backup driver - every week to any member of the public who summons one via the Waymo One app, which works pretty much like any other ride-hailing app.

Even when there's no driver in the car, Waymo has operations specialists who monitor the rides via cameras on the dashboard and the back seat. At a ride's onset, they check that passengers are buckled up and haven't brought more than three people along. Riders can talk to them by pressing a button on the app or on a console in the back seat.

For now San Francisco rides are free - Waymo doesn't yet have permission to charge a fee. And although it's had permission since 2018 to ditch backup drivers in California, it has not yet done so. Rival Cruise has been testing some cars without backup drivers in San Francisco for nine months.

But McGoldrick said its trajectory here to fully autonomous paid rides will be quicker than that in Phoenix.

Back in 2016, lots of smart people said fully autonomous cars would be ubiquitous by 2020. AI researchers told me that their then-toddler-aged kids would never get drivers' licenses.

But the prospect of robot cars - and the promise that they'll improve transportation, end traffic fatalities and reduce congestion - has stayed tantalisingly out of reach.

The technology got very far along - but not all the way. The public got disenchanted, especially after an Uber self-driving car struck and killed a pedestrian in 2018. Companies like Uber and Lyft sold off their self-driving units as the industry consolidated.

"The low-hanging fruit in this field is some combination of slow speeds, simple environments and semi-supervised operations," said Bryant Walker Smith, a long-time industry observer and affiliate scholar at the Stanford Law School Centre for Internet and Society, in an email. "Waymo and Cruise have long been more interested in moon shots."

Those companies need to find "sweet spots that are both technically and financially feasible," he said, noting that while Phoenix is technically much easier than the Bay Area, it's also much less lucrative.

Current ride-hailing has low expenses, he said "an Uber trip is basically just a poorly paid driver in a midtier car."

But the robot cars fleets, even though they eliminated the labour expenses, have to cover costs for cars that mount up to several hundred thousand dollars each, "as well as a vast infrastructure for remote human monitoring and support."

TV and movies are replete with far-out images of the future. But I was most struck by a low-tech image in the comedy-drama series Casual. The final season, which aired in 2018, purportedly took place a couple of years in the future. How the show signalled that: Lead actress Michaela Watkins arrived at her home in a ride-hailing vehicle. The camera briefly panned to show that no one was in the driver's seat.

That's the kind of naturally interwoven use of robot cars that futurists - and Waymo, Cruise, etc. - are betting on. 

 - TNS