Thousands of drivers are involved in fatal auto accidents every year in California. Any new technology that can help people drive more safely is welcome. Technology has its limits though, and is no substitute for human judgment. Safety on the road ultimately depends more on the care taken by drivers than on any high-tech gadgets they may use.

One new technology is a system meant to keep cars from drifting out of their lanes. Toyota, Lexus and Mercedes already offer these systems on some models. They will soon be joined by Ford, which will call its device the "Lane Keeping System."

A camera, mounted over the rearview mirror, is supposed to detect lane markings in the road and be able to gauge when the car is getting too close to the markings. It warns the driver by vibrating the steering wheel. If the driver does not make a steering correction, then the system takes over the power steering and makes the correction itself.

To the extent this all works the way it is supposed to, it can increase safety. In certain conditions, though, the cameras have difficulty detecting lane markings, for example, when the car is driving into direct sunlight, in heavy rain or on curves.

Even when the technology works as intended, the care taken by human drivers remains crucial to safety on the road. ""As vehicles are made safer, drivers may compensate by engaging in riskier behavior," the director of the Center for Automotive Research at Stanford told the New York Times.

Source: The New York Times, "Trying to Nudge Drowsy Drivers," Randall Stross, Jan. 21, 2012