## 4 Conclusions  
In this paper, we proposed a smart lifejacket for navigating passengers to mustering points or embarkation decks during vessel evacuations. A combination of haptic navigation, UWB localization technology, wireless connectivity and local processing capability is applied to a lifejacket, turning it into a lifesaving appliance capable of addressing some of the more challenging aspects of a vessel's emergency evacuation procedure. Each passenger can receive a personalized evacuation route, one that takes into account both the status of the ship and the state of the individual, be guided through it in conditions of low visibility and have their position being made known to the ship's personnel. The latter makes feasible the rescue of trapped or disabled passengers.  
There are a number of limitations in the study. Due to practical considerations, it was not feasible to test the system on a broader scale or for an extended period of time. For similar reasons, it was not possible to test the devices with a sizable number of participants.  
A detailed description of the smart lifejacket and its implementation was given, along with a presentation of the haptic navigation system and its operation. Section 3 details the results of testing the navigation functionality and the successful guidance of the user to the intended location, as well as the key outcomes based on the evaluation process that was followed. Because of these encouraging results, it is our belief that the smart lifejacket we developed within the SafePass project has real potential to improve the evacuation procedure and preserve human lives, and its location-support technologies are viewed as being broadly acceptable and usable by both crew and passengers [4]. In the future, we plan to focus on improving the navigation algorithm and user experience and, additionally, reduce the production cost, something which will hopefully facilitate the adoption by the maritime industry.  
Conceptualization, A.S. and L.K.; methodology, A.S. and M.K.; software, A.S. and M.A.; hardware, P.K. and A.D.; validation, M.K.; writing---original draft preparation, A.S., A.D. and L.K.; writing---review and editing, A.S.; supervision, L.K. and A.A.; project administration, L.K.; funding acquisition, A.A. All authors have read and agreed to the published version of the manuscript.  
\begin{table}
\begin{tabular}{c c c c} \hline  & **Minimum** & **Maximum** & **Average** \\ \hline \multicolumn{4}{c}{**Usability**} \\ \hline The smart lifejacket was easy to put on & 3 & 5 & 4.54 \\ \hline The smart lifejacket was comfortable to wear & 1 & 5 & 4.23 \\ \hline It was easy to connect the smart lifejacket with the smart wristband & 4 & 5 & 4.15 \\ \hline It was easy to activate the navigation button on the smart lifejacket & 4 & 5 & 4.85 \\ \hline \multicolumn{4}{c}{**Helpfulness**} \\ \hline The haptic navigation on the smart lifejacket was helpful in the scenario performed & 7 & 10 & 9.38 \\ \hline The haptic navigation would be helpful in a real-life evacuation of a large passenger vessel & 5 & 10 & 8.77 \\ \hline The haptic navigation would be helpful in a real-life evacuation of a large passenger vessel, & 5 & 10 & 9.08 \\ \hline \end{tabular}
\end{table}
Table 2: Evaluation results.  
**Funding:** This work is part of the SafePass project. SafePass has received funding from the European Union's H2020 research and innovation programme under grant agreement No. 815146. Content reflects only the authors' view.  
**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.  
**Data Availability Statement:** Not applicable.  
**Conflicts of Interest:** The authors declare no conflict of interest.