AMPLITUDE CONTROL AND DETECTION IN AN ELECTROHYDRAULIC DYNAMIC LOADING SYSTEM
AN AMPLITUDE CONTROL UNIT IS DESCRIBED WHICH HAS BEEN DEVELOPED TO IMPROVE THE PERFORMANCE OF A SERVO- CONTROLLED ELECTROHYDRAULIC SYSTEM BEING USED FOR FATIGUE TESTING OF ROAD MATERIALS. THE AMPLITUDE CONTROL UNIT ALLOWS THE LOAD AMPLITUDE TO BE KEPT WITHIN PLUS MINUS 1 PER CENT OF THE FULL-SCALE LOAD AMPLITUDE WHEN THE STIFFNESS OF THE TEST SPECIMEN CHANGES MONOTONICALLY THROUGHOUT THE TEST. THE UNIT IS ALSO SUITABLE FOR AMPLITUDE CONTROL DURING CONSTANT DEFLECTION AMPLITUDE TESTS. A SIMPLIFIED VERSION OF THE AMPLITUDE CONTROL UNIT CAN BE USED AS AN AMPLITUDE DETECTOR UNIT WHICH WILL DETECT ANY FALL, DURING A FIXED SAMPLING PERIOD, OF A SIGNAL PEAK VOLTAGE TO BELOW A PRESELECTED VALUE. THIS FEATURE CAN BE USED, FOR EXAMPLE, TO TERMINATE A FATIGUE TEST ONCE THE STIFFNESS HAS DROPPED BY A GIVEN AMOUNT. /AUTHOR/
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Supplemental Notes:
- No Lr 415, 8 PP, 11 FIG
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Authors:
- STILL, P B
- Publication Date: 1971
Media Info
Subject/Index Terms
- TRT Terms: Amplitude; Amplitude modulation; Detectors; Dynamic loads; Electrohydraulic mechanisms
- Old TRIS Terms: Electrohydraulic systems
- Subject Areas: Highways; Pavements;
Filing Info
- Accession Number: 00207387
- Record Type: Publication
- Files: TRIS, ATRI
- Created Date: Mar 7 1972 12:00AM