This paper presents an optimize method of the well known Redundancy Optimization Problem (ROP) using a combined ANT Colony System (ACS) and Universal Moment Generating Function (UMGF). The ACS searches for the minimum cost solution by selecting the appropriate components for a series-parallel system, given a minimum system reliability constraint. The UMGF is used to estimate the system reliability value during search. This approach is an example of a computationally efficient method to apply ACS optimization to problems for which repeated calculation of the objective function is impractica
