BV 11:3 FRICTION MEASURING TRAILER. DESCRIPTION AND OPERATING INSTRUCTIONS

THE VTI BV 11:3 MEASURING TRAILER IS TO BE TOWED BY A CAR AND IS DESIGNED FOR RECORDING THE COEFFICIENT OF FRICTION OF RUNWAY SURFACES. APPROXIMATELY 80% OF THE BRAKING TORSION IS FED BACK TO TWO SUPPORTING WHEELS AS DRIVING TORSION, THUS REDUCING THE REQUIREMENTS ON THE CAPACITY OF THE TOWING CAR. IT IS EASY TO MAINTAIN A CONSTANT SPEED, EVEN ON SURFACES WITH HIGH FRICTION COEFFICIENTS. THE TORSION APPLIED TO THE TEST WHEEL DUE TO THE FRICTION FORCE IS MEASURED BY MEANS OF A SPECIAL TORSION TRANSDUCER. THE SPEED OF THE TRAILER IS MEASURED BY MEANS OF A TACHOGRAPH TRANSDUCER, DRIVEN BY A ROLLER CHAIN. A CABLE PLACED BETWEEN THE TRAILER AND THE TOWING CAR CONNECTS THESE ELECTRIC SIGNALS TO A STRIP CHART RECORDER PLACED BESIDE THE DRIVER, WHERE THE MOMENTARY VALUE OF FRICTION COEFFICIENT AS A FUNCTION OF SURFACE LENGTH CAN BE RECORDED. THE MEASURING SYSTEM IS POWERED FROM A BATTERY OF THE TOWING CAR (12 V D.C.), AND THE DURATION OF MEASUREMENT IS CONTROLLED BY A TOGGLE SWITCH. /TRRL/

Language

  • English

Media Info

  • Features: Figures; Tables;
  • Pagination: 10 p.
  • Serial:
    • Issue Number: 44a

Subject/Index Terms

Filing Info

  • Accession Number: 00207681
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: R&d Rpt
  • Files: TRIS
  • Created Date: Jun 11 1974 12:00AM