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Rolling resistance, sometimes called rolling friction or rolling drag, is the force resisting the motion when a body (such as a ball, tire, or wheel) rolls on a surface. It is mainly caused by non-elastic effects; that is, not all the energy needed for deformation (or movement) of the wheel, roadbed, etc., is recovered when the pressure is removed.
SAE J1269 and SAE J2452 performed on new tires. SAE J2452 is a standard defined by the Society of Automotive Engineers [1] to measure the rolling resistance of tires. [2] Where the older standard, SAE J1269, produces measurements of rolling resistance under steady-state (i.e. thermally equilibrated) operating conditions, SAE J2452 produces measurements during a transient history of speed that ...
The rolling resistance coefficient (RRC) indicates the amount of force required to overcome the hysteresis of the material as the tire rolls. Tire pressure, vehicle weight and velocity all play a role in how much force is lost to rolling resistance. The basic model equation for SAE J2452 is: Rolling Resistance (N / lbs) = (+ +) where: is the ...
Hertz solved the contact problem in the absence of friction, for a simple geometry (curved surfaces with constant radii of curvature). Carter considered the rolling contact between a cylinder and a plane, as described above. A complete analytical solution is provided for the tangential traction.
SAE J1269 is a standard test defined by the Society of Automotive Engineers [1] to measure the rolling resistance of tires under conditions of thermal equilibrium. [2] [3] SAE J2452 is an alternative procedure for measuring rolling resistance under conditions similar to a vehicle coastdown event, where the tire is in a roughly isothermal condition (but not thermal equilibrium).
Rolling resistance is the force that resists the rolling of a wheel or other circular object along a surface caused by deformations in the object or surface. Generally the force of rolling resistance is less than that associated with kinetic friction. [74] Typical values for the coefficient of rolling resistance are 0.001. [75]
Solving a model based on the Magic curve with high frequency can also be a problem, determined by how the input of the Pacejka curve is computed. The slipping velocity (difference between the velocity of the car and the velocity of the tire in the contact point) will change very quickly and the model becomes a stiff system (a system whose ...
Vehicle dynamics is the study of vehicle motion, e.g., how a vehicle's forward movement changes in response to driver inputs, propulsion system outputs, ambient conditions, air/surface/water conditions, etc. Vehicle dynamics is a part of engineering primarily based on classical mechanics.