ANALYTICAL COMPARISON OF METHODS FOR ASSESSING THE TRANSIENT DIRECTIONAL RESPONSE OF AUTOMOBILES

This paper addresses the interpretation of data obtained from transient response tests currently used to evaluate the response to steering of highway vehicles. For the random input test, calculated results from a computerized model of a passenger car are used to demonstrate that (1) coulomb friction in the steering system tends to reduce the values of yaw rate and lateral acceleration coherence functions at frequencies less than 0.5 Hz and (2) the sideslip angle "transfer function" has interesting properties related to the amplitude of the steering input. Two phase planes, called the "angle plane" and "curvature plane," present results for step/ramp and sinusoidal input tests. The angle plan provides information concerning the slip angles occurring at the vehicle's front and rear tires. The curvature plan displays both the curvature of the path of the vehicle's center of gravity and the reciprocal of the distance from the center of gravity to the instantaneous center of rotation. Curvature plane results are used to provide a detailed summary of the response information fed back to a driver during an obstacle-avoidance maneuver.

• Supplemental Notes:
  • IAVSD Symposium, Cambridge, England, September 7-11, 1981.
• Corporate Authors:

  Highway Safety Research Institute

  Huron Parkway and Baxter Road
  Ann Arbor, MI  United States  48109
• Authors:
  • Fancher, P S
  • NISONGER, R L
  • Winkler, C B
  • Guo, Kun
• Publication Date: 1981

Media Info

• Features: Figures; References;
• Pagination: 14 p.

Subject/Index Terms

• TRT Terms: Alternatives analysis; Automobiles; Simulation; Steering; Test procedures; Testing; Transient analyzers; Vehicle dynamics
• Uncontrolled Terms: Transient response
• Old TRIS Terms: Vehicle responses
• Subject Areas: Highways; Vehicles and Equipment; I95: Vehicle Inspection;

Filing Info

• Accession Number: 00361908
• Record Type: Publication
• Source Agency: National Highway Traffic Safety Administration
• Report/Paper Numbers: HS-032 696
• Files: HSL, TRIS, USDOT
• Created Date: Jun 30 1982 12:00AM