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Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations

This report is an archived publication and may contain dated technical, contact, and link information
Publication Number: FHWA-RD-95-197
Date: December 1996

Development of Human Factors Guidelines for Advanced Traveler Information Systems and Commercial Vehicle Operations: Comparable Systems Analysis


In-Vehicle Safety Advisory and Warning Systems (IVSAWS)


IVSAWS provides warnings on immediate hazard and road conditions/situations affecting the roadway ahead of the driver. It provides sufficient advanced warning to permit the driver to take remedial action (e.g., to slow down). This system does not encompass in-vehicle safety warning devices that provide warning of imminent danger requiring immediate action (e.g., lane change/blind spot warning devices, imminent collision warning devices, etc.). In addition, it provides for the capability of both automatic and manual aid requests.

Immediate Hazard Warning

IVSAWS may provide hazard proximity information to the driver by indicating the relative location of a hazard, the type of hazard, and the status of emergency vehicles in the area. Specifically, this might include notifying the driver of an approaching emergency vehicle or warning the driver of an accident immediately ahead.

Road Condition Information

This function provides information on road conditions, such as traction, congestion, or construction, within some predefined proximity to the vehicle or the driver's route.

Automatic Aid Request

The automatic aid request function provides a "mayday" signal in circumstances requiring emergency response where a manual aid request is not feasible and where immediate response is essential (e.g., severe accidents). The signal will provide location information and potential severity information to the emergency response personnel.

Manual Aid Request

The manual aid request function encompasses those services that are needed in an emergency (police, ambulance, towing, and fire department). It will allow the driver to have access from the vehicle without the need to locate a phone, know the appropriate phone number, or even know the current location. This function also may include feedback to notify the driver of the status of the response, such as the expected arrival time of service.

Vehicle Condition Monitoring

This function provides the driver with the capability to track the overall condition of the vehicle and notifies the driver of current problems, as well as potential problems. This function may be interactive, providing the driver with the capability of interrogating the system about problems and obtaining more details about the situation.

Cargo and Vehicle Monitoring (CVO-Specific)

This function is similar to vehicle condition monitoring, but more information may be conveyed to the driver (e.g., more precise indication of engine performance). Cargo-related conditions also can be monitored, providing the driver with information such as cargo temperature, humidity, and vibration. This function also may distribute this information to dispatch and company managers.





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