There are now more than half a million Tesla electric vehicles on the road with Autopilot version 2, according to statistics put together by a MIT autonomous vehicle research scientist Lex Fridman.

To be exact, there are about 528,570 says Fridman, who released data on MIT’s Human-Centred Artificial Intelligence website on Sunday (US time).

That’s about three quarters of all Teslas delivered, a figure which Fridman considers significant, particularly in the goal to reduce traffic accidents.

The data, which was aggregated from quarterly investor reports, autopilot usage rates gathered in a separate MIT study as well as mileage data from a variety of sources including from CEO and founder Musk himself, shows the proliferation of Autopilot 2-enabled vehicles starting in Q4, 2016.

All in all, Fridman’s research estimates that over 1.5 billion miles (over 2.4 billion kilometres) have been driven on Autopilot to date, and of that about 868 million miles (almost 1.4 billion kilometres) on Autopilot 2 (AP2).

Extrapolated, the numbers suggest that by January 2020, over 2.2 billion miles (over 3.5 billion kilometres) will have been done using the autonomous software, with over 1.4 billion miles (over 2.2 billion kilometres) of that on AP2.

But why is this significant?

The safety of Tesla vehicles is something that the company is keen to impress; with 5-star ratings from both the US-based NHTSA (National Highway Safety Administration) and most recently from Euro NCAP (New Car Assessment Programme), the EV maker’s most popular vehicle, the Model 3 has passed with flying colours.

Both agencies reported on testing the Model 3 that it was the safest car each agency had ever tested, with Euro NCAP saying the Model 3’s safety assist features, which are the outcome of Autopilot 2 hardware and software, “particularly impressed“.

What is it that distinguishes Autopilot 2 from its predecessor, Autopilot 1 (AP1)?

Data gathered from millions of real world miles driven by over half a million vehicles allows the company to hone its algorithms with an accuracy far above that of computer simulations, using a suite of sensors including 8 cameras, a radar and ultrasonic sensors for poor conditions when visibility is low.

The difference between Autopilot 1 and Autopilot 2 (which includes Full Self Driving) was demonstrated recently by Youtuber KmanAuto, who took two Teslas – a Model S with AP1 and a Model X with AP2 – for an identical spin along what he refers to as a “worst case scenario road”.

During the drive, the AP1 vehicle with its very limited single front camera fails several times, requiring intervention by the driver.

The vehicle with AP2, however – Tesla’s own ground up approach, KmanAuto points out, is capable of projecting a 3D-based route that can predict road features that are not possible with AP1, such as elevation change.

The difference in the drives is almost tangible even just viewed from the desk – with extra cameras with long focal length, and wide focal length as well as side view cameras allow AP2 to follow lane lines more precisely.

Where the AP2-enabled Model X deftly takes a blind right turn for example, the Model S with AP1 would have left the lane according to KmanAuto.

In the entire drive, the Model X with AP2 requires human intervention only once (see 3:38 in the video below), on what KmanAuto terms a stretch of road with “extreme difficulty”.

“On this test, AP2.x absolutely NAILS IT! Successfully navigated the test road,” writes KmanAuto in his video description.

He also notes that AP1 has improved over time, although its accuracy can never reach that of AP2.

“As an example of [fleet] learning, with AP1, as I’ve had that vehicle since 2016 and take this road often, at time stamp in the video of 5 minutes, until summer 2018, AP1 would skim the curb.

“Over time, with driver input (correction), AP1 no longer actually hits the curb. It still [wanders] too close for comfort. AP2 has no problems visually seeing the curb and maintains it’s line properly in the same spot,” the Youtuber writes.

Fridman’s conclusion on half a million semi-autonomous cars with Autopilot 2?

Posting on social media platform Twitter, Fridman said on Sunday morning,”The possibilities for Autopilot at such a large scale are exciting, esp for driver safety.

Good luck to @ elonmusk and @ Tesla team in tackling this important engineering challenge.”

Reference: Fridman, Lex. (2019, January 3). Tesla Vehicle Deliveries and Autopilot Mileage Statistics. Zenodo. http://doi.org/10.5281/zenodo.2530449