According to numbers submitted by Apple to California's Department of Motor Vehicles, 23 of the company's 69 registered self-driving testbeds were active between December 2018 and November 2019. Collectively, the fleet of modified Lexus RX450h SUVs logged 7,544 miles during the reporting period, down from 79,754 miles in 2018.
Apple reported 64 disengagements across the 7,544 miles driven, which equates to 8.48 disengagements per 1,000 miles. This compares to a whopping 69,510 disengagements, or 871.65 disengagements per 1,000 miles, recorded in 2018. At the time, Apple's system was reported, on a disengagements-by-mile basis, as the worst-performing test platform in California. By contrast, then-front runner Waymo managed 0.09 disengagements per 1,000 miles over the same evaluation period.
While the improvement seems impressive, it should be noted that disengagement reporting is not a hard science. Typically, disengagements are defined as instances in which a self-driving vehicle's autonomous systems are unable to process current conditions, forcing it to pass control back to the human driver. Human interventions also count as disengagements.
As explained by Apple in a letter to California's DMV last year, the company in 2018 took a "conservative" approach to disengagements that required "drivers to proactively take manual control of the vehicle any time the system encounters a scenario beyond our currently proven abilities." Further, the company said its "software self-monitors and returns control back to the driver when it encounters any errors or issues during operation."
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