An autonomous car heads to Beijing from Chongqing in June last year. Equipped with multiple sensors, the car fully controls its own speed, braking and steering.
Commuters may dream of autonomous vehicles that relieve the hassle of driving, but the reality of urban centers means the technology still has a way to go
Jayson Au had been cruising hassle-free in his Tesla Model S. He had turned on Autopilot, the car's driver assist feature, and was feeling relaxed as he passed through Hong Kong's Cross-Harbour Tunnel to pick up his family after a trip to Macao.
Suddenly, he was snapped awake by the din of an alarm.
He had fallen sleep, and the alarm was going off because his hands had slipped from the steering wheel. He had no idea how long he had been asleep - possibly a couple of minutes.
"I felt lucky that Autopilot really did steer for me," said the Hong Kong real estate agent, recalling the incident later. "But I also think it was Autopilot that lowered my awareness and caused me to fall asleep."
Au bought the Model S after the Hong Kong Special Administration Region approved limited use of Tesla's Autopilot system on city roads last year.
He was not alone. More than 7,000 electric cars were registered with the city's transportation authority by the end of November. Seven years ago, it was fewer than 100. The rapid rise has been fueled, in part, by large tax breaks for drivers who go green with environmentally friendly vehicles.
Tesla made billion from the Chinese market last year, about 15 percent of its global revenue, and continues to hold the No 1 spot in Hong Kong.
However, the response from drivers to the company's Autopilot function has been mixed.
Elon Musk, the CEO of Tesla, has said Autopilot is "50 percent safer than a human driver". Yet Hong Kong motorists believe it will take some time before the technology is able to handle the traffic in one of the most densely populated cities in the world, where streets are packed with other vehicles, and pedestrians can come out of nowhere.