Advantages and practical limitations of mathematical continuity in cam profile design

The basics of cam profile design are discussed with emphasis on mathematical profile types i.e., polynomial versus trigonometric. Comparisons are made and recommendations on the applicability of the various profiles with respect to their dynamic performance are extracted from existing texts. A literature search was done into specific cam system dynamic performance. The categories researched were: a) shock spectrum analysis with return profiles as a forcing function, b) cam shaft wind up, c) follower stiffness effects, d) crossover shock and jump phenomena, e) drive errors to the cam, f) manufacturing tolerance effects, g) curve types, h) return spring surge, and finally, i) the effects of friction at zero velocity. A three degree of freedom lumped parameter computer model was written for rise-return cams commonly used as the drive mechanism for the optics in a xerographic machine. The model was used to investigate the differences between seventh order polynomials and cycloidal curves as well as many of the above listed dynamic phenomena