Traction and Stability of Front-, Rear-, and Four-Wheel-Drive Trucks 520213
THIS report describes the behavior of vehicles on tangents or curves with brakes or excess torque applied to the front, rear, and each of the four wheels. Each condition is analyzed on the basis of the external forces acting on the vehicle.
The analyses are compared with the actual behavior of each vehicle on the ice, inasmuch, as ice is not only a convenient surface, but also represents one of the most hazardous driving conditions. Moreover, any reaction that is obtained on ice will be obtained on any other surface if a given set of wheels is caused to break traction by the application of brakes or excess torque.
Following the analyses of each type of drive, data are presented on the drawbar pull of front-, rear-, and four-wheel-drive vehicles on ice with various loads under static, spinning, and dynamic conditions. From these data the coefficients of traction are computed, which are applied to the design of a vehicle for maximum drawbar pull.