GLOBAL ACQUISITION OF WEATHER AND ROAD CONDITIONS IN DIFFICULT SITUATIONS / SLIPPERINESS EARLY WARNING SYSTEM
International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada === The safety of winter road traffic demands efficient winter maintenance. The highway authorities should be able to salt the roads just before the formation of ice. On the other hand the use...
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| Language: | en_US |
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International Foundation for Telemetering
1986
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| Online Access: | http://hdl.handle.net/10150/615284 http://arizona.openrepository.com/arizona/handle/10150/615284 |
| Summary: | International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada === The safety of winter road traffic demands efficient winter maintenance. The highway authorities should be able to salt the roads just before the formation of ice. On the other hand the use of salt should be minimized because salt burdens the environment and the budget. A SLIPPERINESS EARLY WARNING SYSTEM for detection and prediction of ice should assist the highway authorities. The following four kinds of ice and their causes are of interest:
*black ice/glazed ice: rainfall on undercooled road surface, *frost: freezing moisture on slowly cooling down road surface *advection dew: sublimation of warm air on undercooled road surface *compact snow : pressured snow.
The system should permit two options:
- warning system for the driver, - measuring system for the general weather forecast.
The temperature, humidity and precipitation must be tested at dangerous places such as bridges, slopes and ridges. The road surface conditions such as temperature, covering, and degree of moisture and the amount of salt must be inquired about at several points at a dangerous place.
The dates of weather and road conditions are to be transmitted from the dangerous place to a switching point over a distance of 10 km by a 2-wire-line. The test equipment for up to 10 places is connected to the same line. The data are transmitted by a pulse telemetry system from the switching point to local and central authorities.
Since there is generally no power supply along the roads and highway except small power for telecommunication, the SLIPPERINESS EARLY WARNING SYSTEM has to operate with a power of 10 W/ 10 V DC for the 10 test equipments and transmitters along the 2-wire-line. This is a very hard condition in relation to using traditional sensors that need power for heating to prevent icing. Therefore some new sensors are developed and the sensors, the electronic equipment, and the transmitter are pulsed every 5 minutes.
Air temperature and humidity are tested by sensors that are used by the weather forecast services. A new COMPACT SENSOR is developed to determine the road surface data. Additionally, an INFRARED SENSOR detects the state of the road surface. The analog voltages of the sensors are transmitted by an ANALOG MULTIPLEXER to an ANALOG DIGITAL CONVERTER. The digital data of weather and road conditions are transformed to a FSK signal and transmitted.
A 8085 MICROCOMPUTER controls testing, data processing, signal transforming, transmitting, and timing at the dangerous place. The local and central authorities will have data and alarm presentation by a PC graphic display. |
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