## 4 Conclusions  
In this study, a swivel mechanism for paraplegic patients made with stainless steel 316L was examined to compare its properties with suggested alternatives. AA 6061 and Ti6 Al4V were chosen as alternatives regarding their strength-to-weight ratio and cost. A 3D model of the swivel plate was developed with SolidWorks software 2023, and the three materials were simulated to investigate their performance when in operation. The investigation was conducted when the swivel was in its collapsed state and when it was fully extended. The two alternatives had higher yield strength and factor of safety, which puts them in the position of substitutes for the SS 316L. From this analysis and known knowledge of the cost of these materials, the optimal replacement considering cost is AA 6061. Although SS 316L has better surface aesthetics, further treatment may be needed to achieve better surface aesthetics for AA 6061 by anodizing [29; 30] and laser treatment for Ti6 Al4V [30]. The machining operations suitable for these materials are CNC milling, 3D printing, and laser cutting operations. These methods will ensure accuracy and proper heat distribution within the grains of the structure.  
Conceptualization, O.K.A., B.O.M., H.A.O. and O.A.O.; Methodology, O.K.A., B.O.M., S.D. and H.A.O.; Software, O.K.A. and O.A.O.; Formal analysis, O.K.A.; Investigation, O.K.A. and B.O.M.; Writing--original draft, O.K.A.; Writing--review & editing, O.K.A.; Supervision, S.D.; Project administration, O.K.A., B.O.M., S.D., H.A.O. and O.A.O. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
Data Availability Statement: Data is contained within the article.  
**Acknowledgments:** The authors wish to appreciate the haptic feedback research group for the enabling environment that aided the success of this work. In addition, the contribution of MEE 508 Group 6 is highly appreciated in assisting with the implementation of this work.  
**Conflicts of Interest:** The authors have no conflict of interests.  
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