By space meshing theory and rotation transformation matrix method

two kinds of approximate calculation formula and a precise calculation formula of pressure angle of a cylindrical roller follower globoidal cam are derived. The changes of pressure angle of a globoidal cam mechanism during a dexing period and the changes of pressure angle with the changes of meshing depth of contact line are analyzed

to help select appropriate pressure angle calculation formula in accordance with the different circumstance in actual project calculation. The relative motion between the roller and the cam is an important factor that impact the friction between the roller follower and the cam

for analyze the relative motion of the roller and the cam

the rotation angular velocity formula of the roller and the relative velocity formula of meshing points of the roller and the cam consider the rotation of roller are derived.