The first ever self-driving taxis available to the public have started picking up passengers in Singapore. The pilot scheme is a milestone in the development of self-driving cars, but relatively limited in scope. Only six autonomous vehicles — Renault Zoes and Mitsubishi i-MiEVs modified by MIT-spinoff NuTonomy — will be offering rides, and only then from predetermined pick-up and drop-off points within a 2.5-square-mile radius.

This trial means that NuTonomy has beaten Uber to be the first firm to publicly test autonomous taxis. Uber announced last week that it would be putting its self-driving cars to work in Pittsburgh sometime this month. Uber's taxis will be assigned to passengers at random, while NuTonomy asked local residents to apply to join its pilot scheme before they can request a car. In both cases the rides are free, and the trial vehicles come with an engineer sitting behind the wheel, ready to take over, and a researcher in the back taking notes.

Recode's Johana Bhuiyan tried out NuTonomy's self-driving taxis earlier this year in the same district of Singapore, called North 1. Bhuiyan noted that the car made a number of "abrupt stops" and demonstrated "some clumsy maneuvering," but still managed to safely navigate complicated streets, and that any questionable driving was due to an overabundance of caution:

At one point during the test drive, the car passed another car that was stopped on the left side of the road. To do that, it veered all the way to the right, then abruptly turned left to overtake the stopped car. Had it been a human driver taking a road test, the maneuver would have resulted in an automatic failure.

Presumably nuTonomy's driving software has improved since then, and the company says it plans to have a dozen cars on the roads by the end of the year. CEO and co-founder Karl Iagnemma told the Associated Press that the time frame for the trial was open-ended, and that the company wants to have a full self-driving fleet in operation in Singapore by 2018.

NuTonomy isn't the only firm interested in Singapore either, with automaker Delphi conducting similar trials. Iganemma told the AP that Singapore has proven to be an ideal testing ground for such technology, providing good weather, solid infrastructure, and safe drivers. Singapore's government has also been supportive of self-driving technology, with officials saying they need it to compensate for the nation's limited size and population.

As well as testing the technical competency of self-driving cars, trials like NuTonomy's — and Uber's — will also help answer an important questions: will the public be happy with autonomous taxis? "When people get into the car, some will love it, some will be indifferent and some won’t like it," Iagnemma told The Guardian. "But how many won’t like it – 3 percent of the ridership, or 30 percent? We want to know that number. And Uber wants to know that number, too."

The world’s first self-driving big rig