SERVO-SEISMIC METHOD OF MEASURING ROAD PROFILE

THE METHOD USED TO MEASURE ROAD PROFILE AND TECHNIQUES USED TO ESTABLISH THE ACCURACY OF THESE MEASUREMENTS ARE DESCRIBED. ATTEMPTS TO CORRELATE THE FREQUENCY CHARACTERISTICS OF THE ROAD PROFILE SIGNAL WITH ROAD ROUGHNESS IS DESCRIBED AS EXPERIENCED THROUGH A CAR SUSPENSION. A STATIONARY INERTIAL REFERENCE PLATFORM WITH AN ACCELEROMETER WAS USED TO MEASURE THE VERTICAL DISPLACEMENT OF THE ROAD FOLLOWING WHEEL WITH RESPECT TO THE PLATFORM. AN ACCELERATION SIGNAL FROM THE ACCELEROMETER INDICATES THAT THE PLATFORM HAS MOVED AND THE DOUBLE INTEGRATION OF THE ACCELEROMETER SIGNAL SHOWS HOW MUCH. THE PLATFORM POSITIONING WAS OBTAINED BY USE OF AN ELECTROHYDRAULIC VALVE AND HYDRAULIC ACTUATOR WHICH PRODUCE A MOVEMENT OF THE ACTUATOR RAM THAT IS PROPORTIONAL TO THE ELECTRIC VOLTAGE SUPPLIED TO THE VALVE. THE ACTUATOR RAM WITH THE ACCELEROMETER MOUNTED ON THE END IS THE INERTIAL REFERENCE PLATFORM. THE ANALOG COMPUTER INTEGRATES THE ACCELEROMETER SIGNAL AND FEEDS A SIGNAL PROPORTIONAL TO THE PLATFORM DISPLACEMENT TO THE ELECTROHYDRAULIC VALVE. THE VALVE THEN CAUSES AN OIL FLOW TO THE APPROPRIATE CHAMBER IN THE ACTUATOR. THIS SERVO-SEISMIC SYSTEM OFFERS A QUICK, REASONABLY ACCURATE METHOD OF OBTAINING ROAD PROFILE DATA IN A FORM CONVENIENT TO RAPID COMPUTER ANALYSIS.

Media Info

  • Media Type: Print
  • Features: Figures;
  • Pagination: pp 33-51
  • Monograph Title: Pavement roughness: measuring technique and changes
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00206761
  • Record Type: Publication
  • Files: TRIS, TRB, ATRI
  • Created Date: Aug 5 1994 12:00AM