survey and effects of manufacture and assembly errors on the output error of globoidal cam mechanisms

the output error of the globoidal cam mechanism can be considered as a relevant indicator ofmechanism performance, because it determines kinematic and dynamical behavior of mechanicaltransmission. based on the differential geometry and the rigid body transformations, themathematical model of surface geometry of the globoidal cam is established. then we present theanalytical expression of the output error (including the transmission error and the displacementerror along the output axis) by considering different manufacture and assembly errors. the effectsof the center distance error, the perpendicular error between input and output axes and the rotationalangle error of the globoidal cam on the output error are systematically analyzed. a globoidal cammechanism which is widely used in automatic tool changer of cnc machines is applied forillustration. our results show that the perpendicular error and the rotational angle error have littleeffects on the transmission error but have great effects on the displacement error along the outputaxis. this study plays an important role in the design, manufacture and assembly of the globoidalcam mechanism.