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Slip Ratio and Tration Force
Greetings,
Searching for a slip ratio equation and its relation to the traction force, I found two seemingly different formulas: slip_ratio = (angular_velocity * object_radius - longtitudinal_velocity) / longtitudinal_velocity F = slip_ratio * traction_coefficient And, slip_ratio = (angular_velocity * object_radius - longtitudinal_velocity) / (angular_velocity * object_radius) F = engine_torque * wheel_radius * slip_ratio First question that comes to mind is which one is right? Second, I've used the first equation, however I didn't know what would the slip ratio be if the velocity is 0.0 (Starting up). If it would be zero then the car would never start in the first place. Also what value does the traction coefficient usually have? Now, if the second formula was the right one then the wheel would never stop spinning, because when there's no engine torque it would mean that the traction force would be zero, so the acceleration would never go negative (When going forward). So how can I solve this problem? As a side question, is there any other torque (that I need to worry about) exerted on the wheel besides traction, engine and brakes? Thanks, Abdo Haji-Ali Programmer In|Framez |
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