Fatigue Monitoring Technology

Much attention has been focused this past year on the issue of driver fatigue. One important aspect of this subject is the task of detecting it. Technologies for accomplishing this feat have exploded in the past decade – particularly since the mid-90’s. These technologies have taken a variety of forms, centering on the driver, the vehicle, the physical environment, and the driving environment.

The Technology Frontier

Fatigue measurement technologies may be conveniently categorized in four groups:

  • Operator-based technologies focus on measuring either heightened risk or outright impairment through the observance and/or measurement of various barometers of driver performance. Such performance includes operator vigilance or inattention, alertness versus drowsiness, microsleeps, hypovigilance, performance variability, deterioration of driving skills, and vulnerability to error. The media employed include urine screens, ocular or pupilometric analysis (measuring behavior such as blink rates and eyelid separation intervals), wrist actigraphy (measuring pulse and other sensations), facial analysis (monitoring changes in papillary activity, facial tone, direction of gaze, and head movement and orientation), and EEGs (which measure electrical activity of the brain and heart), among the most commonly discussed. Mechanisms have included wrist monitors, video cameras, EEG and ECG lines (such as scalp electrodes), and electroocculographic (EOG) sensors (e.g., eyelid monitors). Many of these systems couple the data recorded with baseline data about the driver, and complex algorithms which describe and forecast appropriate and inappropriate responses to driving stimuli.
  • Vehicle-based technologies largely build upon sensor-based mechanisms which currently monitor reactions of the throttle, brakes and steering, and input information to devices such as ABS, adaptive damping, engine controls and lane deviation devices used for accident avoidance (e.g., VORAD, Delco Forewarn). These technologies require the vehicle to be “instrumented.”
  • System-based approaches and technologiesare designed to improve driver performance before exposure to the problematic stimuli, or designed to help the driver avoid encountering them. Such technologies include bio-sensitive scheduling and driver assignment, nutrition and exercise programs, napping programs and facilities, and a broad range of health, medical and education programs for drivers, management and healthcare professionals. They also include performance enhancement and comfort improvements such as ergonomic driver’s compartments, improved suspension systems, improved mirror and lighting systems, and other high- and low-tech devices designed to simultaneously optimize comfort and alertness (such as lumbar vibrators).
  • Finally, a number of environmentally-based technologies increase the and recognizability and drivability of the operating environment. Such technologies include lighting, caution bumps, rumble strips, reflectors, signage and other high- and low-technology, physical enhancements of the roadway – particularly where transitions to different roadway surfaces and roadway configurations occur.

Theory and Practice

Some of these technologies have already been demonstrated to be effective. Two examples which illustrate both the ease and sophistication of such technology are wrist monitors and lane deviation detectors. Wrist monitors can alert a complete spectrum of drivers, management and enforcement officials. And detection devises mounted, for example, to the differential might also power down the vehicle. The potential of such technology is so powerful that many advocates and visionaries are already divided into “operator-based” and “vehicle-based” camps. Genuine advocates of motorcoach safety have good reason to be excited.

Unfortunately, the major problems with the evolution of many of these technologies lies not in the realm of mathematics, science and engineering, but rather, in a spectrum of practical problems from the development of acceptable standards and criteria for definitions and measurement, to the ramifications of their application to real-life driving scenarios. As an illustration, one can only imagine what would likely unfold when a fatigue alarm sounds on an activity trip on a coach filled with hyperactive schoolchildren – and the driver announcing not only that a mechanism has detected an unacceptable level of fatigue, and that regulations require him or her to pull over and snooze – but further, that the passengers must all cooperate by maintaining relative silence while he does so. Proponents of such an approach are likely to have better dreams than any such drivers.

In contrast, the practical application of such technology might be crafted to permit drivers to address the problems in a more creative fashion, while providing them with far more sound and urgent information and motivation. As an example, seasoned drivers currently operating on overnight runs who sense the onset of drowsiness in the early morning hours might – with all or most passengers asleep – pull over, take a short nap, or even take a brisk stroll outside the vehicle. If and when noticed and confronted, such clever drivers might misinform inquisitive passengers that the engine was overheating – and needs to cool down. Such an excuse – even though usually malarkey – would likely be far more palatable, and far less frightening, and could buy the driver the time and freedom to obtain some needed rest (even if an actual nap is out of reach). The appropriate physical response – not operating the coach for a reasonable time period thereafter – could easily be monitored in either “real time” (via radio-controlled or GPS equipment) or after-the-fact (via trip records generated by the technologies themselves).

Analog and Digital Marriage

A critical and growing problem with digitalia is its replacement of knowledge and judgment with information. One transportation-related indicator of this enigma can be found in the increase of rape and molestation on paratransit and special education pupil transportation services which has accompanied the transition from manual to computerized scheduling. As many transportation experts know intuitively, but few admit, technology makes for a swell honeymoon. But it also makes for a rocky marriage.

Filtering the technology and its information through a prism of knowledge, judgment and common sense will likely comprise an important part of the overall solution – and hopefully some creative alternatives to outright lying-to-the-passengers can be devised. Finding the optimum solutions here will likely take a lot of effort and ingenuity, and a lot of responsible information-sharing. But creativity and improvisation are the motorcoach industry’s strong suit. This author would pit our best and brightest against any operating problem.

The next installment on this issue – “Fatigue Monitoring Reality” – will explore the labyrinth of technical and non-technical issues such approaches and technologies are likely to confront if and when they actually work. Stay on board for this one: It is likely to be a long and interesting journey.

Because driver fatigue may be the industry’s greatest genuine safety issue, its solutions are likely to deliver substantial payoffs in a range of areas from reduced insurance premiums to marketing opportunities. As a recently-completed National Academy of Science study focusing on home-to-school travel just concluded, bus transportation is the safest form of public transportation. If we can enhance motorcoach safety even further, perhaps we may even discover some new justification for raising fares.

Publications: National Bus Trader.