AN OPTICAL CORRELATION METHOD FOR THE DIRECT MEASUREMENT OF TRANSIENT SIDESLIP AND SLIP ANGLES OF MOTOR VEHICLES

EIN KARRELATIONSOPTISCHES VERFAHRENZUR DIREKTER MESSUNG VON INSTATIONAREN SCHWIMM-UND SCHRAGLAUFWINKELN AN KRAFTFAHRZEUGEN

This paper presents a method which enables the direct measurement of sideslip and slip angles, also for transient driving conditions. The method is based on the principle of the non-contact velocity measurement at the vehicle in two coordinates. From the two measured velocity vectors, the instantaneous guide motion and thus the sideslip angles, respectively the slip angles can be determined. The sensors for the measurement of the longitudinal and lateral velocity have been developed by the Leitz Company Wetzlar. They are working according to an optical correlation method with spatial-frequency filtering in which the surface structure of the road is reproduced on a grating, and the passing light is collected by a photographical recorder. The frequency of the receive signal is proportional to the velocity with which the picture field is moved, normal to the grid lines. A low-frequency constantlight component is formed in the signal by object structures which are greater than half of the grating constant of the detector grating, and it is suppressed by means of a prism grating by push-pull arrangement of two photo recorder signals. For the sign determination, the cross sensor has been set for carrier frequency, using a radial prism grating, applicated on a rotating circular disk. The principle of the non-contact velocity measurement has been realized for the first time in an equipment, practicable for vehicle measurements. Measurements at various driving conditions, f.e., at a circular path, and also at transient conditions, as change of direction, driving in a sine curve and frequency response confirm that the measuring equipment meets well the requirements of accuracy, handiness, and universal application at the vehicle, and it is superior to the former methods of measuring slip angles. With this method, an open gap in the vehicle measuring technique has been closed. It can be assumed today, that the optical correlation method will be of great importance, also in other fields of application for motor vehicle engineering. /Author/

  • Corporate Authors:

    Franckhlsche Verlagshandlung

    Pfizerstrasse 5, Postfach 640
    7000 Stuttgart 1,   Germany 
  • Authors:
    • Zamotor, A
  • Publication Date: 1975

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Filing Info

  • Accession Number: 00132064
  • Record Type: Publication
  • Source Agency: Highway Safety Research Institute
  • Files: TRIS
  • Created Date: Oct 29 1977 12:00AM