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/

  • Supplemental Notes:
    • No Lr 415, 8 PP, 11 FIG
  • Authors:
    • STILL, P B
  • Publication Date: 1971

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Filing Info

  • Accession Number: 00207387
  • Record Type: Publication
  • Files: TRIS, ATRI
  • Created Date: Mar 7 1972 12:00AM