A comparison of three different techniques for optimal allocation of tolerances and clearances in four-bar function generators

Abstract

The paper presenb a comparative study of the technology of containing dynamic programming (CDP), discrete dynamic programming (DI) and parametric programming (PI') as applied to the solution of the problem of optimal allocation of tolerances and clearances in four-bar function-generator linkages. For this purpose three different mechanisms generating the functions y.-sinx, y= logwx and y= x have been considered. The allocation problem has been solved using the and pp techniques for both ± 1° and ±O.So limits on mechanical error considering both normal and uniform distributions for the location of pin centres in the respective clearance circles. The results show that the parametric programming technique yields strictest tolerance and clearance values but lakes minimum computation while discrete dynamic programming technique yields comparatively liberal tolerance and clearance values and takes moderate computation time.