The US National Transportation Safety Board (NTSB) has published its recommendations following last year’s fatal crash involving a Tesla driver using their car’s Autopilot feature.
The NTSB determined that the probable cause of the Florida crash was a truck driver’s failure to yield the right of way and the Tesla driver’s ‘inattention due to overreliance on vehicle automation’.
The NTSB also noted that the operational design of the Tesla’s Autopilot system permitted the driver to become too reliant on the automation, allowing ‘prolonged disengagement from the driving task’ and enabling the driver to use it in ways ‘inconsistent with manufacturer guidance and warnings’.
“While automation in highway transportation has the potential to save tens of thousands of lives, until that potential is fully realized, people still need to safely drive their vehicles,” said NTSB Chairman Robert Sumwalt.
“Smart people around the world are hard at work to automate driving, but systems available to consumers today, like Tesla’s ‘Autopilot’ system, are designed to assist drivers with specific tasks in limited environments.”
Such systems require the driver to pay attention at all times and to be prepared to take control immediately if something goes wrong, noted Sumwalt.
“System safeguards, that should have prevented the Tesla’s driver from using the car’s automation system on certain roadways, were lacking and the combined effects of human error and the lack of sufficient system safeguards resulted in a fatal collision that should not have happened,” said Sumwalt.
Among its findings, the NTSB’s report said that the Tesla’s automated vehicle control system was not designed to, and could not, identify the truck crossing the car’s path or recognise the impending crash. As a result, it did not slow the car, provide a collision warning alert or activate the automatic emergency braking.
The Tesla driver’s pattern of use of the Autopilot system indicated an over-reliance on the automation and a lack of understanding of the system’s limitations, said the report.
The NTSB warned that the risk of driver misuse remains if automated vehicle control systems do not automatically restrict their own operations to appropriate conditions.
The way in which the Tesla Autopilot system monitored and responded to the driver’s interaction with the steering wheel was not an effective method of ensuring driver engagement, found the NTSB, noting that Tesla had since made design changes to the system.
The NTSB also found that fatigue, highway design and mechanical system failures were not to blame for the crash, and that there was no evidence the truck driver was distracted by the use of a mobile phone.
The NTSB issued seven safety recommendations based on its findings, addressing the need for:
- event data to be captured and available in standard formats on new vehicles equipped with automated vehicle control systems;
- manufacturers to incorporate system safeguards to limit the use of automated control systems to conditions for which they are designed and for there to be a method to verify those safeguards;
- the development of applications to more effectively sense a driver’s level of engagement and provide an alert when engagement is lacking; and
- manufacturers to report incidents, crashes, and exposure numbers involving vehicles equipped with automated vehicle control systems.
The abstract of the NTSB’s final report is available here.