On The Optimization Of Spatial Cam Mechanisms Considering Mechanical Errors

Abstract

In this paper, an optimal spatial cam mechanism design is modelled and studied considering the influences of two mainly mechanical error sources, manufacturing and assembly, on output functions and contact conditions in three-dimensional space. A cylindrical roller follower with a crowned surface is investigated using surface contact analysis (SCA). Optimization design is conducted by using an interface coupler to integrate and automate interactive processing of the commercial software Mathematica, and multifunctional optimization system tool, MOST, on a personal computer. The optimization problem for the spatial cam mechanism is formulated to include constraints on pressure angle, displacement error, and contact path bias, all of which should fall within the desirable bounds. The objective function is the maximum absolute value of the displacement error that is to be minimized. Results show that the process reported in this paper can make spatial cam mechanism motion more accurate without increasing manufacturing cost. A sensitivity analysis is also conducted to show how design variables affect the performance of a spatial cam mechanism.