Lane departure warning systems

These systems, also called lateral drift warning systems, use a forward-facing, windshield-mounted camera that tracks the position of the vehicle in the lane by watching the painted lane markers on each side of the road; the system issues an alert when the vehicle starts to drift. It uses image processing to identify lane markers by detecting the contrast between the white painted line and the darker pavement.

Most systems issue a noise similar to what a driver would hear when crossing a grooved-pavement "rumble strip" on the highway. Speakers on either side of the cab alert the driver to which way the vehicle is drifting. The systems are smart enough to know not to alert the driver when a turn signal is on, and they don't issue warnings at lower speeds, when a vehicle may be turning, according to Iteris Inc., which markets the systems.

The technology has limitations. Because it relies on machine vision technology, it won't work in foggy conditions or on roads that don't have clear lane markings. So far, the systems alert only the driver, not the carrier.

The systems cost about US$1,000 per vehicle. But on the highway, Iteris claims, trucks equipped with the technology can reduce rollover accident rates by 68 per cent.

At Schneider, driver feedback so far has been "very positive" after tests of lane departure warning systems on interstate highways, says Damman. But on secondary roads, where there are no white lines on the sides of the road, the results have been "not so good." Nonetheless, Damman says, "the technology is getting better, and we continue to look at it."

Lane change/merge warning systems

These systems use side-mounted, short-range radar or ultrasonic waves to "see" vehicles in the driver's blind spot and produce an alert if the driver attempts to merge into an occupied lane.

Together, the three collision-avoidance systems -- forward collision, lateral drift and lane departure -- could help mitigate 60 per cent of truck crashes, says James Sayer, program director in the human factors division of the University of Michigan's Transportation Research Institute. There's just one problem.

"None of these systems are talking to each other," says Palmer, noting that too many consoles and different types of alerts can confuse a driver, especially during a critical moment. "We want systems that integrate," she says. Palmer also wants the ability to receive real-time alerts when the systems are activated.

Sayer is program manager for the Integrated Vehicle-Based Safety Systems initiative, a government-funded research project that aims to address those integration issues. The goal is to integrate the three technologies to reduce false positives and provide a single, coordinated system whose warnings are easy for drivers to recognize. In the future, there might be seven different warning systems on the truck. "How do you convey the intent, the message, without confusing them?" Sayer asks.

Getting the systems to work together is also key. For example, the lane departure system could sense that the vehicle is rounding a sharp curve and convey that contextual information to the collision detection system so it knows that the object dead ahead is not actually in the vehicle's path.