# Integrated Tolerance and Fixture Layout Design for Compliant Sheet Metal Assemblies
## 6 Conclusions  
The results of this paper evidence that the integration of production process design and fixture layout design is indispensable. An integrated design of these two factors is developed and applied to an industrial sample case. The results are compared with the results of the non-integrated strategy, in which the fixture layout is optimized first and then the production strategy. The relative production cost is obtained as 2.25 and 4 for the integrated and non-integrated strategies, respectively. The integrated strategy results in a lower production cost while it maintains a higher geometrical quality. The \(C_{pu}\) of KPCs that are achieved by the integrated strategy are 1.8, while these values are 1.4 in the non-ingratiated strategy. The dependence of fixture layout on the deviation forms and tolerances of the produced parts is the reason for the superiority of the integrated approach. Consequently, integrating the design of the fixture layout with the production strategy results in a higher quality and lower production cost than designing the fixture layout for a broader variety of forms and tolerances of the parts. Conceptualization, A.R.A., M.H., K.W., B.S., R.S. and S.W. ; methodology, A.R.A. and M.H. ; investigation, A.R.A. ; visualization, A.R.A. ; software, A.R.A. ; formal analysis, A.R.A. and M.H. ; writing--original draft, A.R.A. ; writing--review and editing, M.H., K.W., B.S., R.S. and S.W. ; supervision, K.W., B.S., R.S. and S.W. ; project administration, K.W., B.S., R.S. and S.W. ; resources, K.W. and R.S. ; funding acquisition, R.S. and S.W. All authors have read and agreed to the published version of the manuscript. This research was funded by Swedish Foundation for Strategic Research (SSF) under the grant for Smart Assembly 4.0 project and by the German Research Foundation (DFG) under the grant number WA 2913/25-1: \"Tolerance optimization of statically under- and over-constrained assemblies\". This work was carried out in collaboration within Wingquist Laboratory and the Area of Advance Production at Chalmers in the project Smart Assembly 4.0. Their support is gratefully acknowledged. The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. The following abbreviations are used in this manuscript:  
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