SAN FRANCISCO — In August, Tesla electric cars will offer "full self-driving features," CEO Elon Musk tweeted over the weekend.
But aside from that brief description, written in response to an owner's comments about Tesla's Autopilot suite of driver-assist features, Musk didn't give any more details about just how autonomous his cars would be.
In the tweet, which addressed a concern about Autopilot wavering in high-traffic lane-merging situations, Musk said "that issue is better in latest Autopilot software rolling out now & fully fixed in August update as part of our long-awaited Tesla Version 9."
He added that "to date, Autopilot resources have rightly focused entirely on safety (and) with V9 (version 9), we will begin to enable full self-driving features."
Just what "full self-driving" means to Musk remains in question. Tesla would not comment beyond the CEO's tweets.
The Society of American Engineers has a ranking system for self-driving cars, with SAE Level 1 referring to systems such as basic cruise control, while Levels 4 and 5 refer to vehicles that need little to no human oversight.
Tesla's Autopilot is considered an SAE Level 2 system, which combines adaptive cruise control and lane keeping assist technology. Tesla repeatedly has asserted that its system needs driver monitoring and is not meant to replicate self-driving tech.
Fully and semi-self-driving auto tech has been under a microscope lately as federal investigators continue to investigate crashes of vehicles that were using such systems.
In March, an Uber self-driving car killed a pedestrian in Arizona when its sensors and on-board safety driver failed to notice the woman crossing in the middle of the road in the dark.
And two recent Tesla crashes involved Autopilot, one in which a California driver was killed when his car veered into a highway barrier and another when a distracted Utah driver hit a parked fire truck at 60 mph. Neither had their hands on the wheels for some time before the crash.
Tesla electric cars such as the Model S and Model X are known for their sleek looks, hefty price tags and rapid acceleration. The company is rushing to ramp up production of its entry-level Model 3 sedan.
And there's a chance Tesla could soon be rocket-ship fast. Musk also tweeted that the new version of his Roadster two-door sports coupe will feature a SpaceX option, a nod to his rocket company.
"SpaceX option package for new Tesla Roadster will include ~10 small rocket thrusters arranged seamlessly around car," Musk tweeted. "These rocket engines dramatically improve acceleration, top speed, braking & cornering. Maybe they will even allow a Tesla to fly …"
It's tempting to see this as a joke. But with Musk, you never know. After all, most people thought he was joking about selling flame throwers, and now they're in customer hands.
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