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EVALUATION ON AN AVM (AUTOMATIC VEHICLE-MONITORING) SYSTEM IMPLEMENTED CITY-WIDE IN ST LOUIS (MO) - A SUMMARY REPORT

NCJ Number
53103
Author(s)
G C LARSON
Date Published
1978
Length
19 pages
Annotation
THE AUTOMATIC VEHICLE MONITORING (AVM) SYSTEM IN ST. LOUIS, MO., TO TRACK THE POSITION OF VEHICLES AND TO MONITOR THEIR GENERAL STATUS AND POLICE RESPONSE TIME IS EVALUATED.
Abstract
SEVERAL TECHNOLOGIES ARE THE BASIS OF AVM SYSTEMS IN GENERAL. THESE TECHNOLOGIES ARE USUALLY BASED ON ONE OF FOLLOWING CONCEPTS: RADIO RANGING (TRILATERATION), PROXIMITY SENSING, OR DEAD RECKONING. SOME SYSTEMS, KNOWN AS HYBRID SYSTEMS, INCORPORATE TWO OR MORE OF THESE CONCEPTS ALONG WITH OTHER CONCEPTS SUCH AS COMPUTER CORRECTION OF TRACKING ERRORS. THE MONITORING ASPECT OF AN AVM SYSTEM USUALLY INCLUDES STATUS AS WELL AS LOCATION INFORMATION. IN POLICE APPLICATIONS, THE STATUS ASPECT MAY DESCRIBE WHETHER A VEHICLE IS RESPONDING TO A POLICE CALL FOR SERVICE; AT A SCENE; OR INVOLVED IN ROUTINE PREVENTIVE PATROL, CRIMINAL PURSUIT, OR IN NEED OF EMERGENCY ASSISTANCE. THE COMPUTER-ASSISTED DEAD RECKONING SYSTEM IMPLEMENTED CITYWIDE IN ST. LOUIS, MO., IS CALLED FLEET LOCATION AND INFORMATION REPORTING (FLAIR). CAR LOCATION IS DETERMINED BY DATA SUPPLIED FOR EACH CAR, INVOLVING DISTANCE TRAVELED AND DIRECTION OF TRAVEL. INCREMENTAL DATA ARE TRANSMITTED TO A BASE STATION FOR EACH UPDATE PERIOD (ABOUT 1.2-SECOND INTERVALS) TO TRACK A VEHICLE'S LOCATION CONTINUOUSLY ON A COLOR TELEVISION-TYPE MAP DISPLAY. FIVE OBJECTIVES OF FLAIR ARE TO REDUCE POLICE RESPONSE TIME, TO IMPROVE OFFICER SAFETY, TO REDUCE VOICE-BAND CONGESTION, TO ENHANCE COMMAND AND CONTROL CAPABILITIES, AND TO IMPROVE POLICE FORCE SUPERVISION. THE METHODOLOGY FOR EVALUATING FLAIR INVOLVED TECHNOLOGICAL, OPERATIONAL, ATTITUDINAL, AND COST-EFFECTIVENESS ANALYSES. EVALUATION RESULTS WERE UNFAVORABLE FOR RESPONSE TIME REDUCTION, FAVORABLE FOR IMPROVED OPERATIONS DUE TO DIGITAL COMMUNICATIONS, AND MIXED IN THE REALIZATION OF OTHER OBJECTIVES. POOR SYSTEM PERFORMANCE HAD SOME INFLUENCE ON THE RESULTS. RESEARCH APPLICATIONS OF AVM THAT ARE EXPECTED TO DEVELOP CONCERN TOTAL PATROL CAR RESPONSE TO AN ALL POINTS BROADCAST MESSAGE, DEGREE OF CONFORMITY TO ESTABLISHED PATROL ROUTINES, AND SPATIAL DEPENDENCE BETWEEN CRIME OCCURENCES AND PATROL PASSINGS. SUPPORTING DATA ARE PROVIDED. (DEP)