# Dimensional Tolerances in Mechanical Assemblies: A Cost-Based Optimization Approach
## 3 A Proposal for Tolerance Synthesis
Therefore, the advantages of applying the proposed method can be summarized as follows:

* the consideration and prioritization of non-quality costs through the determination of functional constraints;
* the ability to individually consider the feasibility of each manufacturing process;
* optimization of manufacturing costs related to dimensional tolerances using a low-complexity and time-efficient processing algorithm, which can be implemented using commercially available computer software. The proposed method has certain limitations and cannot be directly applied to 3D tolerances. ## 6 Conclusions and Future Work

A method is proposed to optimize manufacturing costs by considering the concepts of quality loss in the design of dimensional tolerances. The methodology is detailed in the algorithms provided and has been shown to be highly effective compared to conventional tolerance allocation methods found in the literature. The proposed method offers distinct advantages over similar existing methods, particularly in its simultaneous optimization of manufacturing costs and costs associated with quality loss. This includes a simplified manufacturing cost calculation function and precise control over non-quality costs. The calculation function utilizes discrete intervals connected by linear functions, resulting in efficient processing times. Control over the non-quality cost is achieved by specifying an economic safety factor. Implementation of the proposed method has shown significant cost savings compared to conventional approaches, which can be particularly impactful in mass production volumes prevalent in today's globalized market. The authors acknowledge that the current proposal only addresses the synthesis of unidimensional tolerances and are actively working on extending the methodology to include three-dimensional approachesin future work. In addition, the application of stochastic simulation using the Monte Carlo method is being considered. Conceptualization, E.U., A.B. and M.S.G.T. ; methodology, E.U. and M.S.G.T. ; software, E.U. and M.S.G.T. ; validation, E.U., A.B. and M.S.G.T. ; formal analysis, E.U. and M.S.G.T. ; investigation, E.U. and M.S.G.T. ; resources, A.B. ; data curation, A.B. ; writing--original draft preparation, E.U. and O.H. ; visualization, E.U. and M.S.G.T. ; supervision, M.S.G.T. ; project administration, O.H. ; funding acquisition, M.S.G.T. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable. The authors declare no conflict of interest. ## References

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