Are ADAS and AEB Finally Ready for Prime Time?

As regulators ramp up plans to introduce more safety regulations for trucks, a crash that took place near Mt. Pleasant, Pennsylvania, in 2020 provides some cautionary insight for drivers, fleets, and those drafting the new rules.

Presenting at Heavy Duty Trucking Exchange in Phoenix, Arizona, last September, Michael LaPonte, senior highway safety investigator with the National Transportation Safety Board, said advanced safety systems such as collision mitigation and automatic emergency braking cannot prevent all types of crashes.

Summarizing the board's findings, Laponte said drivers still have a responsibility to operate their vehicles safely and drive according to the conditions. Fleets have a maintenance obligation to ensure the systems are properly calibrated and fully functional. And regulators must establish performance standards for such systems.

“We have found collision avoidance systems to be a great tool, but they have a long way to go before they are ready for prime time,” he said at the end of his presentation. “We have reiterated some safety recommendations to the National Highway Transportation Safety Administration to ensure they include guidance and standards for manufacturers to be able to put these systems into use.”

Overturned Bus Looked Like 'A Black Wall'

To illustrate the challenge, LaPonte used a five-vehicle crash that took place at 3:30 a.m. on Jan. 5, 2020, on the westbound lanes of the Pennsylvania Turnpike (I-70/76) in Mt. Pleasant Township, between New Scranton and Denegal.

Weather and road conditions were less than ideal at the time of the crash. Light snow had been falling for several hours, and the temperature was below freezing. Road maintenance crews had reported seeing no ice on the road. Two of the truck drivers involved in the crash reported the road was wet but not icy or snow-covered.

The local speed limit was 70 mph, but an advisory sign located less than half a mile ahead of a curve (the crash site) recommended motorists reduce their speed to 55 mph before entering that section of roadway. That section of the highway was unlit.

The accident report indicates three tractor-trailers, one motorcoach, and a car were involved. Evidence collected by investigators indicates the crash sequence began when the motor coach, traveling at a recorded speed of 77 mph, departed the travel lanes, hit an embankment on the right side of the road, and overturned. It came to rest on its side, straddling both westbound lanes, with its dark underside facing oncoming traffic.

Moments later, a FedEx tractor-trailer traveling at 53 mph entered the curve ahead of the overturned motorcoach. The driver told investigators the bus looked like “a black wall.” A forward-facing camera corroborated that observation. The driver steered left and struck the motorcoach at 21 mph, coming to rest and blocking the left shoulder and the left lane.

The first tractor-trailer was struck from the rear about two seconds later by another tractor-trailer (UPS 1) which had entered the curve at 71 mph. It struck the rear of the first trailer but never struck the motorcoach. The vehicle’s speed at impact was 56 mph.

Next, a car rounded the curve. The driver recognized the crash scene ahead and steered right to avoid the first two tractor-trailers. It crossed the right shoulder and rode up onto the embankment before coming to rest alongside the second tractor-trailer.

Finally, a third tractor-trailer (UPS 2) entered the curve at 69 mph. Upon seeing the crash scene, the driver steered right, rode up onto the embankment, struck the car, and came to rest between the car and the embankment.

The motorcoach driver, two motorcoach passengers, and the driver and codriver of the first UPS truck died in the crash. About 49 motorcoach passengers were injured. The FedEx truck driver was not injured, but his co-driver suffered minor injuries. The driver of the car, the car’s two passengers, and the driver and co-driver of the second UPS rig were not injured.

Post-crash Assessment

Paraphrasing from the actual investigation report, LaPonte noted the likely cause of the crash was the motorcoach driver traveling too fast for the conditions and failing to maintain control of his vehicle while in a descending curve.

“The driver made several excessive steering inputs ... trying to regain control of the bus,” LaPonte said. “Although we couldn't determine it 100%, we're fairly certain that his engine brake was on before the crash, which also contributed to his loss of traction.”

LaPonte credited the first tractor-trailer driver (FedEx 1) with driving properly for conditions, taking appropriate evasive measures, and for slowing his truck sufficiently to reduce the severity of the impact.

The following truck (UPS 1) had maintained an appropriate five to seven-second following distance, but still went into the curve too fast for conditions. While that may not have been a causal factor in this case, being unable to bleed off enough speed before impact certainly did add to the severity.

NTSB came to a similar conclusion for the third truck into the crash.

But one factor grabbed the investigator’s attention: The second truck, UPS 1, had a collision warning system installed but it wasn’t working at the time. It hadn’t been working for a year and a half, LaPonte noted.

Non-Functional Safety Systems

“The radar on the front of the truck was out of alignment,” LaPonte said. “Penske [the owner of the vehicle] first detected that flaw in July of 2019, but it was never repaired. It had been noted several times on maintenance records up until the time of the crash in January 2020.”

Why the systems weren't repaired is unclear, but current safety regulations and defect reporting requirements do not include advanced safety systems. Drivers are not required to report non-working ADAS systems. Nor are repairs required before operating vehicles on public roadways.

“No one ever puts together that that's a safety system, the same as your air brakes, same as your tires,” he said. “Any kind of safety system that would affect the operation of a vehicle should be noted when there's a flaw. But it's not in the regulation, so drivers never wrote it down.”

Following the investigation, NTSB followed up with Penske and UPS, convincing the two companies to pay closer attention to non-functioning ADAS systems and do the required repairs. Both companies agreed to revise their policies.

“As a result, between May of 2020 and December of 2021, Penske put 6,300 vehicles out of service nationwide because crash avoidance systems didn't work,” said LaPonte. “And UPS changed their driver training to ensure drivers recognize a problem when they see it and write it up.

“These technologies are advancing at such a rapid rate that the industry is struggling to keep up with those changes,” he added.

A Regulated Solution

The lack of performance standards for collision avoidance/mitigation systems is another wrinkle in the struggle to keep up with advancing technology.

In the course of its investigation, NTSB discovered there were no federal performance standards for collision mitigation systems.

“If you want to build a collision mitigation system, you can go out and build one, but there's no guidance on how to do it or what it should be able to do. And that's part of the problem,” LaPonte stressed.

Without such a roadmap, different OEMs have developed proprietary systems while other industry suppliers have independently developed their own systems. They perform differently, the warning thresholds may be different, and the driver interfaces may be different.

“Since there's no such roadmap, everyone's doing it a little bit differently. Nor has NHTSA published testing protocols to ensure the technology meets the performance standards,” LaPonts pointed out.

NHTSA did propose testing protocols back in 2019, but LaPonte said they had no pass/fail criteria and the maximum speed for the test was 45 mph, which doesn’t reflect typical on-highway operating conditions.

Further, LaPonte said the lack of standardization means that camera and radar systems, or fusion technologies that blend the camera’s visual output with data from the radar sensor, makes for different interpretations of what the system sees and how that may or may not trigger an alert.

“If the camera sees the back of a car, you’re likely to get an alert. But what if it sees the underside of a bus? Or a piece of farm equipment that has fallen from the back of a flatbed?” he asked.

Or a bale of hay, or a pedestrian, or an overhead sign?

Quoting figures from the Insurance Institute for Highway Safety, LaPonte told the audience forward collision warning systems are worth the effort. They could reduce crashes by 22%. Automatic emergency braking could reduce crashes by a further 12%. Combined, the two systems could reduce rear-end crashes by as much as 40%.

“NITSA in 2017 did research that suggested AEB systems could avoid 11,500 crashes, which would save 7,700 injuries and 173 fatal crashes,” he said.

In the summary of the published accident report, NTSB indicated the circumstances of the impacts for each of the three trucks were likely outside the capabilities of the collision avoidance system available on the vehicles at the time or were outside the testing performance protocols NHTSA was developing at the time.

Still, NTSB is standing by its recommendation that NHTSA complete the development and application of performance standards for forward collision avoidance systems in commercial vehicles. It is also urging the Federal Motor Carrier Safety Administration to add collision avoidance systems to the driver vehicle inspection reports (DVIRs).

Recently NHTSA proposed a new rule that would require automatic emergency braking (AEB) systems on new passenger cars and light trucks. The industry has been lobbying for a similar mandate for heavy trucks for some time.

Industry sources tell HDT we could see a Notice of Proposed Rulemaking on AEB for heavy trucks as early as July.