Abstract:
METHODS OF MEASURING THE SPEED OF AN OBSERVED VEHICLE DEPEND UPON FUNDAMENTAL TIME-MEASURING INSTRUMENTS WHICH CONSIST OF DETECTING, TIMING, AND RECORDING UNITS. SEVERAL OF THE EXISTING METHODS ARE DISCUSSED WITH BRIEF COMMENT ABOUT CERTAIN CHARACTERISTICS THAT RESTRICT THEIR GENERAL ADAPTABILITY. THE NEW "AUTOMATIC SPEED RECORDER" (PHOTO- VELAXOMETER) IS DESCRIBED AS AN INSTRUMENT DESIGNATED TO MEASURE AND RECORD ACCURATELY SMALL TIME INTERVALS, OR A SEQUENCE OF SMALL TIME INTERVALS. THE STANDARDIZABLE SPEED RECORDER OPERATES ON THE PRINCIPLE OF PHOTOGRAPHING THE MOVING HANDS OF A SYNCHRONOUSLY-DRIVEN PRECISION CLOCK. THE PERFORMANCE CHARACTERISTICS AND RECOMMENDED STANDARD OPERATING PROCEDURES ARE DISCUSSED. CERTAIN ALTERNATIVE CONTROL AND CALIBRATION METHODS ARE PRESENTED. THE PHOTO- VELAXOMETER IS ADAPTABLE FOR RECORDING "SUCCESSIVE SPOT SPEEDS," AS WELL AS "SPOT SPEEDS." /AUTHOR/
Supplemental Notes:
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