Auto safety and human adaptation

Issues in Science and Technology, Winter 2000/2001 by Smiley, Alison

Policy implications

Where public funds are spent on high-technology development, it is incumbent on governments to ensure that adaptive effects are considered. This means observing whether and how driving strategy changes as a result of using a new device before making unfounded predictions on likely improvements in safety. Better predictions require a variety of evaluations. Initially, simple mockups can be used to evaluate driver understanding of how to operate the interface and driver expectations of how such a device would function (for example, the expectation that adaptive cruise control will detect stopped cars ahead). This will give insight into likely driver errors or misunderstandings when using the device. At the next stage, the device can be studied in a driving simulator. Behavior-such as speed, following distances, length of glances required to operate the device, removal of the foot in response to the vibration associated with antilock brakes-can be compared with and without the device being used, and devices with different functionality can be compared, such as adaptive cruise control that merely reduces acceleration versus adaptive cruise control that applies some braking. These results can be used to optimize the functional design.

The final stage involves testing the device on the road to observe how drivers use it in real traffic initially and over time as they adapt to it. For example, do drivers equipped with adaptive cruise control turn more and more of their attention to nondriving tasks such as using a cell phone? Over time, do elderly drivers with vision enhancement systems drive more at night than those not so equipped? In other words, what tradeoffs are made and is the net result likely to improve safety?

Responsible vehicle manufacturers must concern themselves with optimizing these devices to achieve the greatest safety possible. It may not matter if a high-tech VCR or microwave oven confuses its owner. But injury and death can result from a driver who does not understand the functioning of his or her brakes, vision enhancement system, adaptive cruise control, and so on.

It is also becoming clear that some form of education is needed for drivers using vehicles with sophisticated systems. A recent study in Quebec showed widespread misunderstanding by drivers of whether their own vehicles were equipped with antilock brakes (27 percent did not realize they had them) and how braking was affected (47 percent thought anti-lock brakes improved braking on dry surfaces). Anti-lock brakes are just the beginning. Much more complex devices are coming soon. Drivers with adaptive cruise control and vision enhancement systems will have to understand their specific limitations. Manufacturers can and should provide well-designed manuals and educational videotapes. This is already being done for adaptive cruise control systems. However, manufacturers are not in a position to verify through testing that drivers have understood the new technology. It is up to departments of motor vehicles to consider modifications to licensing tests to assess driver understanding of these new technologies. There may even need to be retesting requirements for drivers who buy vehicles equipped with several devices.