THE YAW STABILITY OF TRACTOR-SEMITRAILERS DURING CORNERING: SUMMARY

The yaw stability of tractor-semitrailers in steering-only maneuvers is examined by means of computer simulation and full-scale tests. The tests included as-designed vehicles as well as vehicles modified with frame and front suspension stiffening elements installed. Results show that while tractor yaw instability can occur well below the rollover threshold for certain vehicles, modified stiffness parameters can eliminate such premature yaw instability. Simulation study of the influence of design and operating variables on tractor yaw stability served to classify the relative importance of different suspension stiffness options, as well as tire mix, fifth wheel placement, and trailer loading practices. Results show that remarkably low levels of tractor yaw stability are possible with certain combinations of design and in-use variables. A set of measurements of tractor-semitrailer ride vibrations is also reported as an add-on task to this study.

  • Supplemental Notes:
    • See also report dated June 79, PB80-116775.
  • Corporate Authors:

    Highway Safety Research Institute

    Huron Parkway and Baxter Road
    Ann Arbor, MI  USA  48109

    National Highway Traffic Safety Administration

    1200 New Jersey Avenue, SE
    Washington, DC  USA  20590
  • Authors:
    • Ervin, R D
    • NISONGER, R L
    • MALLIKARJUNARAO, C
    • Gillespie, T D
  • Publication Date: 1979-6

Media Info

  • Pagination: 24 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00305741
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: UM-HSR-79-21-1 Final Rpt., DOT-HS-805-140
  • Contract Numbers: DOT-HS-7-01602
  • Files: NTIS, TRIS, USDOT
  • Created Date: Feb 27 1980 12:00AM