Safety Systems Start With Anti-lock Brakes
This story appears in the June 13 print edition of Equipment & Maintenance Update, a supplement to Transport Topics.
Sales of active safety systems are rising and, as of next summer, the first versions will become mandatory on new U.S. heavy-duty tractors. Two of the largest suppliers to truck makers keep making the systems more capable, but no matter how sophisticated they get, they all start with anti-lock brakes.
Being able to monitor the instantaneous need for braking and apply it precisely to specific wheel-ends is ground level for a structure that could become an active safety system or an autonomous or platoon truck. So, foundation brakes are the foundation of autonomous driver assistance.
Electronic stability control is what will become standard on new Class 7 and 8 tractors as of Aug. 1, 2017, according to last year’s rule from the National Highway Traffic Safety Administration. ESC, available since 2005, provides help in avoiding rollover accidents and minimizes loss of control during swerving.
BEST OF JUNE E&MU: More stories, columns
For Tier 1 suppliers Bendix Commercial Vehicle Systems and Meritor Wabco, the two major producers of active safety equipment, current product development focuses on collision avoidance or mitigation: recognizing and classifying dangerous situations through cameras and radar, and then bringing the truck to a complete stop or close to it if a driver is unable to take control of the vehicle.
“From Navistar’s perspective, safety systems are a very broad topic,” said Steve Gilligan, the truck maker’s vice president of product marketing, but noting that anti-lock brakes “are the foundation.”
“ESC is standard on our vehicles today, and then there are tire-pressure monitoring systems as an option and up to adaptive cruise control,” Gilligan said, referring to cruise control that automatically reduces speed when radar finds a truck is following another vehicle too closely.
Gilligan says Navistar buys from Bendix and Meritor Wabco and lets truck operators specify the system they want.
“It’s difficult to switch on the systems, so fleets tend to stay with a brand,” he said, adding that the two companies compete fiercely on technology advancements. “They’re leap-frogging each other on collision mitigation.”
In addition, software and sensors control not only record what the truck does on the road, but what happens inside of the cab. In April, Navistar began offering the RollTek seat from Indiana Mills & Manufacturing Inc. as an option in its International Pro Star tractors.
The RollTek seat combines seat-belt tensioning with a side airbag and a drop in height to protect a driver in case of a rollover. “It drops the seat to the ground,” Gilligan said of the RollTek option.
Meanwhile, the two big manufacturers, Bendix and Meritor Wabco, are parts of large, international corporations. Bendix is the Elyria, Ohio-based subsidiary of Knorr-Bremse Group of Munich. Meritor Wabco is a joint venture between Meritor Inc. of Troy, Michigan, and Brussels-based Wabco Holdings. NHTSA rulings in the recent past have tended to give the companies’ sales a boost — the reduced stopping distance rule has made air disc brakes more popular, for instance — but executives at both companies said separately that active safety systems have been sold for more than 10 years as technology that makes sense standing alone.
“There’s a lot of competition for capital spending by fleets,” said Jon Morrison, Wabco president for the Americas, at a trucking event this spring. The company gives “everyone a good reason” to use Meritor Wabco’s OnGuard system, he added.
“We’ve sold more OnGuards in the last 20 months than during the first seven years of production,” Morrison said. “We don’t want to just rely on a mandate,” he said after addressing the ACT Research Co. seminar in Columbus, Indiana.
In May, Bendix said it’s had a similar sales pattern, selling 100,000 of its Electronic Stability Program systems from 2005 to 2011, and then 350,000 more systems in the five years after that. ESP is basic electronic stability control, and Bendix calls its newer collision-mitigation systems Wingman, or Wingman Fusion, in the most recent iteration.
From a maintenance point of view, the active safety systems are usually very reliable, said Jim Boyd, manager of fleet technical services at Southeastern Freight Lines, a less-than-truckload carrier based in Lexington, South Carolina.
“They’re not completely trouble-free, but close to it,” said Boyd, who also is chairman of the Chassis and Brake Systems Study Group, or S6, of the Technology & Maintenance Council. Southeastern Freight ranks No. 28 on the Transport Topics Top 100 list of the largest for-hire carriers in the United States and Canada.
In addition to his experience with the Bendix and Meritor Wabco systems used on SEFL’s more than 3,000 tractors, Boyd said he has talked to other maintenance directors at TMC meetings and within the S6 group. He said there appears to be a consensus that the systems are reliable and do not require excessive maintenance.
Since anti-lock brakes can work with either drum brakes or air disc brakes, so can the safety systems. Preventive maintenance practices for brakes and tires don’t change because of the safety systems, Boyd said.
The existing ABS is augmented with additional components and the system is diagnosed and serviced with the software that most shops already have on their diagnostic laptops, he said.
TMC, a division of American Trucking Associations, will hold a collision mitigation technical session at its September meeting in Raleigh, North Carolina. There is broad acceptance of the systems in the maintenance world.
“I’d rate the [safety systems and their sensors] as very, reliable,” Boyd said. “They can fail and require diagnosis, trouble-shooting and subsequent repairs, but the systems are not generally problematic.”
In addition to the two major suppliers, Daimler Trucks North America makes an active safety system called Detroit Assurance that it installs in its Class 8 Freightliner and Western Star Trucks. Kelly Gedert, manager of powertrain and components marketing at DTNA, said the systems need attention if the truck is involved in an accident.
“The radar for the collision mitigation system is mounted in a cutout in the bumper and could be damaged if there was an impact to the middle of the bumper,” Gedert said. “Whether the radar survives this impact or not, the technicians would need to be trained to know how to calibrate the radar when it is installed back into the cutout.”
Similarly, Gedert said the windshield damage can affect the camera that feeds lane-departure warning systems with images.
Overall, “a critical component of successfully utilizing safety systems is driver training to be sure the drivers know how the systems work and utilize the systems to the fullest,” Gedert said. “It could indirectly impact maintenance costs as theory suggests there should be fewer ‘hard’ braking events.”
Southeastern’s Boyd agreed, saying that drivers may be hesitant to accept monitoring features in the systems at first, labeling them as intrusive. However, after they learned how the systems can improve safety, including saving lives, they grew to accept them, he said.
Fred Andersky is a Bendix executive who works on customer solutions and follows government affairs. Drivers should not be ambushed with the systems, he said.
“One thing a fleet should never do is not tell the driver about the safety system,” Andersky said. “The driver may discover the system inadvertently and may try to test the limits of the system.
“Finding the upper limit of a safety system is never a good thing — the laws of physics are never kind to those who attempt to disobey them,” he added.
Bendix’s Wingman and its competitors are designed to assist experienced drivers who behave rationally, Andersky said, noting that is reflected in the training.
“The key message for drivers on active safety technologies is to simply drive normally — in the safe manner he or she always drives,” he said. “If a system activates, the driver should learn from the activation to avoid doing whatever caused the activation in the future. . . . These are driver assistance systems — not driver replacement systems.”
Meanwhile, Andersky said the use of the word “autonomous” can be misleading. Understood properly, new collision mitigation systems and older, basic ESC systems offer autonomous assistance to drivers, he said.
Even DTNA’s experimental Inspiration truck needs a CDL-holding driver inside for operating it. While the autonomous systems in Inspiration can take over the vehicle for a while, truly driverless trucks are not on the horizon, Andersky said.