Automated driving technology such as Tesla's Autopilot and Cadillac's Super Cruise should be designed to have the driver actively engaged at all times, the Insurance Institute for Highway Safety said Thursday.
IIHS, a nonprofit group funded by auto insurers, issued a set of safety recommendations for the design of such systems. The guidelines address ways to minimize driver disengagement and system misuse.
Several Level 2 systems — the highest level currently available for vehicles in production — control acceleration, braking and steering to keep the vehicle traveling at a set speed and centered in the lane, while maintaining a selected following distance from the vehicle ahead. The systems require the driver to remain attentive and ready to intervene, but IIHS said some designs make it too easy for the driver to disengage and heavily rely on the system.
"Unfortunately, the more sophisticated and reliable automation becomes, the more difficult it is for drivers to stay focused on what the vehicle is doing," David Harkey, president of IIHS, said in a statement. "That's why systems should be designed to keep drivers actively engaged."
The group's recommendations include direct and indirect methods of monitoring and detecting driver disengagement, such as eye and head orientation, steering wheel input and lane-departure frequency.
"Designs should also be based on a principle of shared control, and they should have built-in limits that prevent them from being used on roads and under conditions where it isn't safe to do so," according to researchers at IIHS.
Research has shown that when it takes less physical effort to drive — as supported by automated driving technology — drivers are more likely to disengage in the driving task and be tempted to do other things such as text or check email, IIHS said.
The group pointed to the "false sense of security" of these systems and how driver distraction or disengagement can lead to injury or death, as determined by the National Transportation Safety Board last month during a public hearing on the fatal crash of a Tesla Model X in Mountain View, Calif.
The NTSB determined limitations of the Tesla Autopilot system, the driver's overreliance on Autopilot and his distraction — "likely from a cellphone game application," the board said — caused the crash.
IIHS also highlighted systems offered by BMW and Mercedes-Benz that can automatically change lanes when the driver triggers the function with the turn signal. In premapped areas, Tesla's Autopilot can change lanes and exit the freeway without any trigger from the driver, IIHS said. After an update next year, Cadillac's Super Cruise system also will automatically change lanes without requiring the driver's hands to be on the wheel.
"These systems are amazing feats of engineering," said Alexandra Mueller, an IIHS research scientist and lead author of the recommendations. "But they all suffer the same problem: They don't account enough for the behavior of the human being behind the wheel."