VEHICLE LOADING AND HEADLAMP AIM

HEADLAMP AIM IS AFFECTED BY CHANGES IN THE BODY ATTITUDE OF THE VEHICLE CAUSED BY CHANGES IN THE LOAD CARRIED. TO DISCOVER HOW MUCH MISAIM ARISES FROM THIS CAUSE 392 VEHICLES (CARS, LIGHT VANS AND ESTATE CARS) WERE WEIGHED WITH THE PASSENGERS AND LUGGAGE ABOARD. WHEEL LOADS WERE MEASURED ON A SMALL PORTABLE WEIGHBRIDGE AND THE CHANGE IN BODY ATTITUDE DUE TO THE LOADS CARRIED WAS DEDUCED FROM CALIBRATION LOAD/DEFLECTION CHARACTERISTICS, DETERMINED UNDER LABORATORY CONDITIONS, FOR THE 58 DIFFERENT MODELS STUDIED. THIS INDIRECT METHOD OF MEASUREMENT WAS USED IN ORDER TO DISTINGUISH BETWEEN DEFLECTIONS DUE TO LOADS CARRIED AND DEFLECTIONS DUE TO SETTING OF SPRINGS, AS THE LATTER CAN BE ALLOWED FOR BY ROUTINE HEADLAMP AIMING WHEREAS THE FORMER CANNOT. IT WAS FOUND THAT OVER 30 PER CENT OF THE VEHICLES EXAMINED WOULD HAVE HAD AN UPWARDS BODY TILT DUE TO LOADING OF MORE THAN 1/2 DEGREE AND OVER SEVEN PER CENT MORE THAN 1 DEGREE. ALMOST ALL THE TYPES OF VEHICLE IN THIS SURVEY CAN EXHIBIT EXCESSIVE TILT WITHIN NORMAL LOADING LIMITS. THE RESULTS CONFIRM THE NEED FOR SOME FORM OF HEADLAMP OR VEHICLE BODY SELF LEVELLING SYSTEM TO PREVENT EXCESSIVE GLARE FROM HEADLAMPS DUE TO NORMAL VEHICLE LOADS. /RRL(A)/

  • Supplemental Notes:
    • Report No LR 329, 20 PP, 11 FIG, 1 PHOT
  • Corporate Authors:

    Road Research Laboratory /UK

    ,    
  • Authors:
    • Hignett, H J
  • Publication Date: 1970

Subject/Index Terms

Filing Info

  • Accession Number: 00220182
  • Record Type: Publication
  • Source Agency: Road Research Laboratory /UK
  • Files: TRIS, ATRI
  • Created Date: Jun 11 1971 12:00AM