An Analysis of Clutch Judder

Clutch judder is generally assumed to be generated by two possible causes: a particular type of the friction-sliding speed variation; misalignment in the driveline. This paper presents a simulation method by which effect of these two causes on judder phenomena can be evaluated separately. In this method, coefficients representing variations in the axial load on the clutch with misalignments are introduced. Calculated results can satisfactorily explain experimental results such as beat phenomena and variation in torque-time traces. It is also noted that clutch judder is affected considerably by the buildup time of the axial load and the friction-sliding speed variation of the facing.