Like eager youngsters awaiting their first bus ride, a growing number of fleet managers and drivers around the country are anticipating the impending arrival of a new generation of vehicles with electronic stability control technology, or ESC.
Several fleet managers reached by School Transportation News said their districts would be receiving new ESC-equipped buses for the coming academic year, but they weren’t prepared to comment on the record until they had an opportunity to see how the vehicles performed.
Two people who are in a position to comment are Fred Andersky, director of customer solutions for the controls group at Bendix Commercial Vehicle Systems, and Scott Smay, director of engineering and product development for IC Bus. They both agreed that ESC technology is certain to help make a safe mode of transportation safer and destined to dramatically advance the development of collision mitigation technology in short order.
“ESC technology doesn’t replace the need for a safe driver practicing safe driving habits and getting good driver training. We can’t make a bad driver a good driver, but we can help a good driver avoid a really bad, bad day,” Andersky explained.
ESC’s critical interaction is with the brake system—the pads, calipers, drums and air pressure that do the work of stopping a vehicle. The system’s yaw rate and lateral acceleration sensors, steering angle and wheel speed sensors instantly know critical information regarding vehicle speed, direction and driver intent. It responds within fractions of a second to help the driver prevent a vehicle from spinning out or rolling over by slowing the bus through throttle reduction and, if needed, selective applying the brakes.
“Stability gives the driver options. Let’s say we’re fishtailing to the left, we may just want to apply brakes on left steer axle to help the driver out,” Andersky said. “What we want to be able to do is apply brakes when and where necessary to help the driver regain control. It has the ability to read what’s going on with the vehicle, typically, sooner than the driver.”
The National Transportation Safety Board first recommended ESC technology in tractor-trailer rigs five years ago. The National Highway Traffic Safety Administration finalized rules in 2015 to require ESC in trucks and motorcoaches over 26,000 pounds beginning in August 2017. NHTSA projects the requirement will prevent more than 1,700 crashes a year and reduce large-vehicle rollovers by 56 percent.
Thomas Built Buses has partnered with Meritor WABCO to provide factory-installed SmartTrac Electronic Stability Control on its Saf-T-Liner C2 school buses since last September.
Noting the High Point, North Carolina, company’s commitment to “building and designing buses that are safe, efficient and provide customers with the lowest total cost of ownership possible,” Thomas Built Buses President and CEO Caley Edgerly said. “Our ESC technology helps us do just that. Yes, school buses are the safest form of transportation on the road. However, the beauty of ESC is that it can sense bus instability before the driver can, so it actually can help eliminate accidents before they occur. No matter how safe a school bus is, it is even safer if an accident is avoided.”
Cars, trucks…and then buses
Smay and Andersky said the move to install the technology in school buses within the past 18 months is a natural progression. New technology often begins with cars before migrating to tractor-trailers, then single-unit trucks and school buses.
“We have truck customers who say they will not buy trucks unless they have safety systems on them, so the market has pulled technology into the truck side,” Smay said. “I haven’t seen buses ask for it as much so there’s a different dynamic, a different demand.”
He added, “Some of it is awareness and as more people become more aware of the technology, demand will increase. The other factor is when you think of school buses, you think about them starting and stopping at slower speeds. The stability issue comes into the conversation when higher speeds are involved and there are more chances for an accident.”
Andersky noted that school buses already are one of the safest modes of transportation, which cash-strapped school boards will no doubt take into consideration as they weigh the added costs and benefits of ESC technology.
“There is an aspect of, ‘Do we need all this technology? We’re still relatively safe.’ Those are the cost-benefits the NHTSA has to weigh out. But, school buses are used for a lot more than driving kids around neighborhoods.
“You have teams crossing state lines, marching bands going on long trips, buses getting a lot more highway use and more use in more difficult weather conditions,” Andersky said. “This is where the interest in stability comes into play. This is where the ability to be able to help the driver mitigate a potential loss of control that would lead to a rollover in bad weather or unfamiliar highways comes into play.”
Smay noted that ESC can pay for itself in the blink of an eye.
“If you avoid sliding off the road and hitting a tree, you’ve saved the cost. Even if you avoid just sliding into the ditch, you’ve saved the few hundred dollars to tow it out and any damage to the bus,” Smay said.
While the technology comes with more upfront costs, it doesn’t place any special demands on maintenance staffs. Keeping the tires and brakes in good condition maintains stability, which keeps the ESC system in good stead because its components typically don’t wear out.
“There are two areas that have to be considered. If the fleet does have a front-end alignment or front-end work, the steering angle sensor needs to be recalibrated,” Andersky said. “Second, the lateral acceleration and yaw rate sensor is typically on the frame rail. Maintenance is simple: Don’t touch it. Don’t move it. Don’t do anything to it. Leave it alone. If you do move it, which would be a very rare circumstance, it has to be recalibrated.”
Picking Up Momentum
Andersky noted that it took nearly seven years for Bendix to sell its first 100,000 stability systems. It has sold an additional 350,000 in the past four-and-a-half years.
“We see collision mitigation technology moving even faster. Part of the reason is that there are two to three times as many rear-end collisions as rollovers in commercial vehicles,” he said, predicting that technology will be on buses within five years.
“We have it on commercial vehicles today. The evolutionary path will be getting to school buses,” Andersky said. “(Pupil transportation professionals) don’t live in silos; they talk to each other. If someone says, ‘I saw this collision mitigation technology on a bus, you should check it out’…people are going to say, ‘We should look at it.’”
Smay, who said future generations of sensors are sure to be smaller, faster and smarter, emphasized the development of a new technology is a team effort between the bus manufacturer and its suppliers that can often require a seven-figure capital investment and 12 to 18 months of effort. “A lot of testing goes into it so it does what we expect it to do when we expect it,” he said.
But that won’t slow the march of new technology. New safety technology includes adaptive cruise control, which can apply the brakes and warn the driver when following another vehicle too closely.
Bendix, which is a supplier for IC Bus and Blue Bird Corporation, is developing Smart Park technology that will lock the brakes if the driver is not in the seat to help prevent tragedies such as a February 2016 incident in which an unattended bus killed an Indiana principal who pushed a child to safety.
“That’s probably going to be available in the next year to 18 months. It’s going to be one of those technologies that can be a real game changer for the additional safety it can provide in such situations,” Andersky said.
Smay also foresees 360 vision technology that will protect children getting on and off the bus. “You see stories where the driver may lose track of a child who maybe has dropped their pack in front of the bus (and is run over). The system will warn the driver and keep the bus in park or keep its brakes on until the area is clear,” Smay said. “These additional systems are going to be far more important than stability control, but stability control comes first.”
Edgerly agrees. Thomas Built Buses currently offers a suite of technologies on its new BusWise technology platform, including a warning system from Mobileye N.V. that prevents forward and pedestrian collision and lane departure as well as the PV360 multi-camera, which provides a 360-degree view of the bus exterior.
He cited NHTSA statistics that 93 percent of crashes are due to human error, which has prompted the agency to recommend that all vehicles be equipped with a forward collision avoidance system. “The effectiveness of these innovations make them a must for all fleets. But for those fleet managers who are still not convinced, they should review the history of student-transportation related crashes in their district, driver behavior, repair costs, and even weather and road conditions in their area to determine the cost/benefit of opting for collision mitigation and ESC technologies,” he added.
Andersky would like to see ESC become standard equipment on all buses and believes it will eventually happen through regulatory action. More likely, he predicted, districts will simply begin to acquire ESC-equipped buses over time.
“Then they automatically start to order it when they renew because they may find they’re having fewer fender benders or sliding into something on snow less often,” he said. “Districts will want to make sure they have the safest buses they can have. When they see how it works, they’ll ‘get it’ and they’ll want it.”
“Technology is going to continue to evolve. It’s going to get better and it’s going to get cheaper,” Andersky said. “The next 10 to 15 years are going to be really exciting around safety and it will find its way to school buses.”
