Bendix Offers Winter Info on Advanced Driver Assistance Systems – TheTrucker.com

AVON, Ohio – Daylight hours are shorter and temperatures are dropping across the United States and Canada, signaling the season when commercial vehicle drivers are increasingly likely to encounter muddy, snowy and icy road conditions.

Bendix Commercial Vehicle Systems offers tips to help drivers better understand how technology can help them be safer on the roads in difficult conditions.

“During our demonstrations of ride-and-drive safety technology, two questions come up frequently,” said Fred Andersky, director of demos, sales and service training at Bendix. “The first is, ‘What can I expect from collision mitigation on a slippery road?’ and the second is, “Could automatic brake application cause me to lose control?” Ideally, the answers lie in the inclusion of full stability technology as a core element of collision mitigation.

Understanding Collision Mitigation Technologies

The systems are built on Total Stability Control, which has been required on most new Class 7 and 8 air brake tractors in the United States since 2017. Total Stability technologies – generally known in the industry as electronic stability control – are designed to help drivers mitigate rollovers. They are also designed to potentially assist a driver in certain conditions of loss of control or loss of vehicle traction, which can occur in winter weather.

“Like all safety technology, Total Stability is there to assist the driver – the driver is always in control of the vehicle at all times,” Andersky said. “And it’s important to remember that the system has limits: you can drive too fast and negate its benefits. But by building crash mitigation technology on top of stability control – which itself is built on top of the anti-lock braking system – we help drivers and the crash mitigation system stay in control when the brakes are applied.

Collision mitigation systems can help drivers avoid forward collisions by reducing the throttle and/or applying the brakes when the system detects a potentially threatening forward collision. The difference is that instead of a driver physically pressing and lowering the pedals to engage and disengage the brakes and accelerator, a collision mitigation system can perform the interventions using the system’s electronics. braking.

Using information gathered from the system’s radar, camera and sensors, the electronic control unit of a collision mitigation system continuously assesses the vehicle situation. If the system determines that a forward collision is imminent, it sends signals to the brake controller, which may reduce acceleration and/or apply the brakes.

Before cutting the throttle and braking, collision mitigation technology can provide in-cab alerts when the gap between the truck and a vehicle ahead narrows. It can also provide an alert before intervening.

Like a driver, the collision mitigation system may need to brake whether the road is slippery or not.

It’s important to keep this point in mind: safety technologies complement safe driving practices. No commercial vehicle safety technology replaces a competent, alert driver practicing safe driving techniques and proactive, comprehensive driver training.

In terms of road conditions, collision mitigation systems are subject to the same laws of physics as a driver: what happens with brake applications on a slippery surface – a surface with potential loss of vehicle traction? The vehicle slows down and eventually comes to a stop. If a skid begins to occur, the ABS and stability control systems can intervene to help the driver maintain control in certain situations.

The same goes for a collision mitigation system. The obvious difference is that when the driver or the collision mitigation technology brakes on a slippery surface instead of a dry surface, the vehicle needs more time and distance to stop.

Concrete examples

The Bendix team spends part of each winter at the Keweenaw Research Center in Michigan’s Upper Peninsula, where there is no shortage of brutal winter conditions to test vehicles and safety systems.

Joining engineers and other staff on site, Andersky – who holds a Class A CDL and drives regularly at Bendix demonstrations – had the opportunity to get behind the wheel to put a truck through normal demo maneuvers , but on a slippery, packed snow surface. . He drove a 6×4 tractor with a loaded trailer, air disc brakes, and a combined gross weight of 65,000 pounds, and performed tests involving both a stationary vehicle and a slow-moving vehicle.

“The first thing to understand is that the collision mitigation system must sense the situation ahead and then perform calculations to determine if or when alerts or automatic braking are needed,” said Andy Pilkington, Group Director of Bendix ADAS/HAD products. “The faster the truck approaches the vehicle in front (whether stationary or moving), the harder it is to detect and the less time the system has to react. For demonstration purposes, Fred ran two common traffic scenarios to better illustrate the reaction of the system. »

First, when approaching a stationary car at moderate speed, the vehicle’s collision mitigation system detected the situation and intervened as intended: alerting the driver, shutting off the accelerator and applying the brakes to help. However, due to the approach speed and the slippery surface, the vehicle slid, as if the driver had applied the brakes.

“Sometimes there isn’t enough weather or friction with the road surface to provide enough alertness or braking force to soften the impact with the vehicle ahead,” Pilkington said. “In other situations, the truck may decelerate partially and may still hit the front vehicle at a lower speed. And in another set of circumstances, there is enough friction with the road surface and time to sense the situation to avoid impact altogether.

Andersky said the driver must remain alert and deal with potentially threatening situations on their own and that collision mitigation systems are driver assistance, not driver replacement.

The following maneuver, at a higher speed, simulates the common situation of a slow vehicle in a driver’s lane, with the semi-trailer coming quickly onto a slower vehicle. As before, after the system detected the situation, it alerted and applied the brakes – and in both cases, as the vehicle slowed down, the gear reduction alone did not avoid the vehicle ahead. : Andersky had to swerve to avoid the collision.

“The same possibilities detailed in the first maneuver also exist here,” Pilkington said. “Sometimes only an alert is given or limited braking is applied, or in other situations maximum braking occurs; the answer depends on the exact situation, the closing rate with the vehicle ahead and the time the system has to detect the situation and react.

“In other words, the system reacted as it was designed and gave me the ability to act,” Andersky said. “Not so surprising. Whether the vehicle in front is moving or stationary, stopping a loaded tractor-trailer requires more time and distance on a slippery surface.

Science and reality of the road

The coefficient of friction represents the amount of friction between two surfaces – the lower it is, the easier the two surfaces will slide. Compared to a dry asphalt or concrete surface, the coefficient of friction of truck tires on compacted snow or ice is up to 87% lower. Combine this situation with the mass and speed of a vehicle combined – 80,000 lbs. and 55 miles per hour, for example – and that roughly compares to stopping distance on various surfaces, bringing science into the real world.

Bendix’s tests show that the truck that takes 335 feet to stop on dry pavement, for example, will likely take 466 feet to stop on wet road, 965 feet to stop on packed snow, and 1 625 feet – over a quarter mile – to stop on the ice. Almost triple the stopping distance between snow and dry road, and almost five times longer to stop on ice than on a dry surface. This means that the driver and the system must be aware of what is happening on the road in order to react in time.

“It’s the perfect illustration of why driver alerts are so important,” Pilkington said. “Giving drivers time to react before a system intervenes helps capitalize on their abilities to see ahead and also steer, which most of today’s collision mitigation technologies don’t.” .

Pilkington said it also shows the value of the collision mitigation system on a slippery surface: beyond interventions, depending on the situation, the alerts can help re-engage the driver to brake or take other action to avoid a danger. And if the driver steps in to get around the situation, full stability may help them maintain control of the vehicle.

As for any potential loss of control caused by the collision mitigation braking generated by the system, that’s no more of an issue than a driver applying the brakes on the same surface, especially since the stability system complete is already integrated to help keep control.

“Ultimately, safe and alert drivers are the single most important factor in helping to mitigate collisions on slippery roads,” Andersky said. “They have advantages over technology – sight and direction – and they are trained to recognize the crucial factors in increasing tracking distance to create reaction time when the weather turns bad.”