Constrained black box optimization for radioisotope thermal generator manufacturing

Access full-text files




Parga, Jose Rafael, Jr.

Journal Title

Journal ISSN

Volume Title



This thesis aims to optimize the conditions and policies used at Los Alamos National Laboratory for the manufacturing of Radioisotope Thermal Generators used for deep space exploration. This manufacturing faces unique and stringent constraints on their operations as well as extraordinarily rigorous quality control measures to ensure that products will work when deployed. Furthermore, this manufacturing process is new, and no historical data exists to prove the capability of the manufacturing system and what the expected operating costs will be. Through this analysis, a theoretical model is constructed to understand the system dynamics to arrive at a theoretical product throughput. A base case of the manufacturing system is created using values for the system as it is currently envisioned. From this case, the total cost, average total time per product, and the number of products completed are optimized. This optimization is achieved by changing the policies on how batches are formed and when operators should work to use resources most efficiently and ensure that no resource is under or over-utilized. It was discovered that the most efficient policy is to add a half working day on Saturdays which significantly reduces the cost by about $700,000 when compared to having operators work 24/7. Furthermore, this policy can produce more products in less time than the case in which people work a standard shift Monday through Friday and decreases costs by about ~$30,000 utilizing the optimized values. Finally, using cost estimation techniques, the total manufacturing cost including fringe benefits, maintenance, operating supplies, and supervisory labor is estimated to be around $6,000 per product and total cost of $3M per year. The results presented in this thesis can inform Los Alamos National Laboratory on the direction and policies that must be implemented to meet manufacturing targets. Furthermore, the methodology developed can be expanded and applied to other product lines throughout the lab to analyze throughput and stay cost efficient while meeting national security requirements.


LCSH Subject Headings