- BMW, Nissan vehicles showed negligible effect of driver assistance
- Crash-prevention features such as automatic emergency braking still lead the safety way
- Newer versions of driver assistance haven’t changed the rules
Driver-assistance systems may not do much—if anything at all—to improve the crash safety of vehicles on which they’re fitted, according to a new study published by the Insurance Institute for Highway Safety (IIHS) and the Highway Loss Data Institute (HLDI).
The insurance industry-funded group looked at insurance data and crash records to determine the net effect of using such systems, which can use cameras, radar, and lidar sensors to automate some driving systems such as acceleration, braking, and steering.
“Everything we’re seeing tells us that partial automation is a convenience feature like power windows or heated seats rather than a safety technology,” IIHS President David Harkey said.
The agencies looked at older 2013-2017 BMW and 2017-2019 Nissan Rogue vehicles to determine how the systems were being used, and how that impacted crash data. The net finding: None of the systems offered much of a benefit in crash avoidance beyond the integral subsystem of automatic emergency braking.
Driver-assist systems now come standard or can be ordered on more than half of the new vehicles sold in the U.S., under brand names ranging from Nissan’s ProPilot to BMW’s Driving Assistant Plus—to, most notoriously, Tesla’s Autopilot and its so-called “Full Self-Driving” add-on. As the IIHS points out—and as The Car Connection has long concurred—”vehicles equipped with these systems are far from self-driving.” They are unable to adequately monitor and respond to traffic and changes in road conditions.
Even more damning, the IIHS calls these features distractions. “The technology can encourage a false sense of security and induce boredom, causing drivers to tune out,” the agency said in a release.
2018 Nissan Leaf ProPilot Assist
Crash prevention and driving assistance: Two different ideas, technologies
Crash prevention has made major leaps in the past decade with the near-universal implementation of features such as automatic emergency braking, blind-spot monitors, and active lane control. Using sensors and cameras, these systems can detect imminent danger from obstacles ahead, obstacles closing from the rear quarters, or the lack of lane discipline on the part of the driver. Most of these systems, the IIHS reports, are left active all the time.
Driver assistance must be turned on, usually through cruise control. It must be monitored by an attentive driver. To date, no company has delivered a system that exceeds Level 2 automated driving for use on public roads across the country—meaning automated systems can take over some aspects of driving but the driver must remain attentive and focused. Mercedes-Benz has promoted its more advanced Level 3-capable system, which can only be used on certain roads in California and Nevada. (BMW has a similar system in Germany.)
While the crash-prevention features are proven to cut insurance claims, the IIHS reports, driver assistance has only been borne out in theory. In the BMW and Nissan vehicles studied, the IIHS and HLDI study’s data found no reduction in claim rates for vehicles equipped with driver assistance—while claims were 8-25% lower in vehicles with crash-prevention systems.
The caveat: The studies could not assert if driver assistance had been active in vehicles subject to insurance claims. The study also underscores that most driver assistance isn’t used at low speeds, where the preponderance of crashes happen—and that even with driver assistance, crashes that might in theory be mitigated by adaptive cruise control or blind-spot monitors show no lower incidence at higher speeds where the systems might be deployed.
As the IIHS/HDLI study points out, newer technology has emerged since these vehicles were built and sold. That doesn’t seem to change their conclusions much, if at all: Driver assistance is a convenience and not a safety feature, at least in its current state.