Citation

Banks J, Powell P. Transp. Res. Rec. 1997; 1603: 27-33.

Copyright

(Copyright © 1997, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

10.3141/1603-04

PMID

unavailable

Abstract

Smart call boxes are devices similar to those used as emergency call boxes in California. The basic call box consists of a microprocessor, a cellular transceiver, and a solar power source. The smart call box system also includes data-collection devices, call-box maintenance computers, and data recording systems at a central location. The goal of the smart call box field operational test (FOT) was to demonstrate that smart call boxes are feasible and cost-effective means of processing and transmitting data for tasks such as traffic census, incident detection, hazardous weather reporting, changeable message sign control, and video surveillance. The objective of the FOT evaluation was to determine the cost-effectiveness of smart call boxes, but because of schedule slippage the evaluation focused on only functional adequacy and capital costs. The concept for the smart call box system was found to be feasible but not necessarily optimal for the tasks involved. System integration was a major problem. Also, the number of external devices that can be attached to a single call box while maintaining the economic advantages of the system is restricted by wiring costs and limitations of the solar power supply. Test system performance was mixed. One subtest was canceled before the installation of equipment, functional systems were produced for only three of the four remaining subtests, and reliable operation was observed in only one case. In most cases, system costs will be dominated by the expense of installing wiring. Consequently, smart call boxes will be cost-effective compared with hardwire systems at many sites but may not be cost-effective compared with alternative wireless systems.

Language: en