NON-DIMENSIONALIZING TYRE DATA FOR VEHICLE SIMULATION

Non-dimensional relationships are proposed for tire side force and self-aligning moment as functions of steer angle, camber angle, load and friction coefficient. Braking force is also non-dimensionalized and determined as a function of slip ratio, steer angle, load and friction coefficient. Following a brief review of results of earlier work by Fiala and Sakai, on which the approach is based, we show dimensionless plots for several tires including: 5.00-16 motorcycle tire (two treads and inflation pressures), P225/7OR15 radial, P185/80R13 radial and 185/70VR15 SG35. It is found that most of the side force data at different loads can be made to fall on a single dimensionless curve as a function of combined steer and camber angle ratios, provided the camber angle does not exceed 10 degrees. Non-dimensional self-aligning moment data also compress to a single curve for each tire when plotted against the non-dimensional steer angle parameter. Similarly, it is shown that dimensionless braking force at various loads becomes a single curve as a function of the slip ratio parameter for zero steer angle, and as a function of the steer angle parameter for constant values of the slip ratio parameter. Comparisons are also presented between the non-dimensional curves for specific cases of similar tires. Recommendations are made for use of the dimensionless plots for vehicle simulation, smoothing or fairing of tire data, reduction of the number of required tests and comparison of tires of varying size, pressure and construction parameters.

• Supplemental Notes:
  • Road Vehicle Handling, I Mech E Conference Publications 1983-5. Sponsored by Automobile Division of the Institution of Mechanical Engineers under patronage of Federation Internationale des Societies d'Ingenieurs des Techniques de l'Automobile (FISITA) held at the Motor Industry Research Association, Nuneaton, 24-26 May 1983.
• Corporate Authors:

  Mechanical Engineering Publications Limited

  P.O. Box 24, Northgate Avenue
  Bury St Edmunds, Suffolk IP32 6BW,   England 
• Authors:
  • Radt Jr, H S
  • Milliken Jr, W F
• Conference:
  • Road Vehicle Handling, I Mech E Conference Publications 1983-5. Sponsored by Automobile Division of the Institution of Mechanical Engineers under patronage of Federation Internationale des Societies d'Ingenieurs des Techniques de l'Automobile (FISITA) he
• Publication Date: 1983

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 229-240

Subject/Index Terms

• TRT Terms: Alternatives analysis; Braking performance; Engineering moments; Force; Radial ply tires; Simulation; Tires
• Old TRIS Terms: Braking force; Moments; Non-dimensional relationships; Radial tires; Side force
• Subject Areas: Highways; Vehicles and Equipment;

Filing Info

• Accession Number: 00387047
• Record Type: Publication
• Source Agency: National Highway Traffic Safety Administration
• Report/Paper Numbers: C133/83, HS-036 359
• Files: HSL, TRIS, USDOT
• Created Date: Jul 30 1984 12:00AM