# Towards a Cyber-Physical Range for the Integrated Navigation System (INS) System (INS)
## 2 Related Work
### Testbeds  
In order to identify relevant publications, a Systematic Literature Review (SLR) was conducted, following the methodology in [22]. The objective of this literature review was to study modern bridge testbed environments with an explicit focus on surface vessels, so as to identify and classify existing architectural models, hardware and software tools that are utilized within contemporary bridge testbed environments; and to identify and classify the capabilities and functionalities deployed within such environments. The literature review was carried out in the ACM Digital Library, the IEEE Xplore, ScienceDirect, Springer Link, and Wiley Online Library. The search string (_(\"maritime\") OR (\"marine\")) AND ((\"ship\") OR (\"essel\")) AND ((\"testbed\") OR (\"testbed\")) OR (\"test bed\")) was used. Only technical reports and scientific articles published in conferences, workshops, and journals written in English, between January 2010-December 2020 were considered. The initial search resulted in a total of 9437 potentially relevant articles. Next, articles with contributions that are directly focused on surface vessels' bridge testbeds, their capabilities, the services that they provide, or their usage were sought. This was done in three stages: The titles and metadata of the results were perused in the first stage, and the number of results decreased to 74. In the second stage, the abstracts and conclusions of the rest of the articles were assessed to eliminate irrelevant articles. Next, the references of the articles were reviewed, for back tracing. By means of this process potential articles which may contribute to the goal of the study were identified. The result was that 16 articles were eliminated and nine articles were added to the list, so that the third stage began with 67 articles. The full texts of these were assessed and finally 16 articles were found to be relevant; these are shown in Table 1. In the column titled \"Type\", C denotes a conference paper, and J denotes a journal article. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**No** & **Title** & **Ref.** & **Year** & **Type** \\ \hline
1 & A generic testbed for simulation and physical based & & & \\  & testing of maritime cyber-physical system of systems & [23] & 2019 & C \\ \hline
2 & A study on the verification of collision avoidance support system in real voyages & [24] & 2015 & C \\ \hline
3 & Comparing simulation with physical verification and validation in a maritime test field & [25] & 2020 & J \\ \hline
4 & eMaritime integrated reference platform & [26] & 2016 & C \\ \hline
5 & HAGGIS: A modelling and simulation platform for e-maritime technology assessment & [27] & 2014 & C \\ \hline
6 & LABSKAUS—A physical platform for e-maritime technology assessment & [28] & 2014 & C \\ \hline
7 & Learning from automotive: Testing maritime & & & \\  & assistance systems up to autonomous vessels & [29] & 2017 & C \\ \hline
8 & Mobile Bridge—A portable design simulator for ship bridge interfaces & [8] & 2018 & J \\ \hline
9 & Physical testbed for highly automated and autonomous vessels & [30] & 2017 & C \\ \hline
10 & Save maritime systems testbed & [31] & 2014 & J \\ \hline
11 & Simulation environment for risk assessment of e-navigation systems & [32] & 2015 & C \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The final result of the SLR. The SLR identified two bridge testbeds: the eMaritime Integrated Reference (eMIR) platform [38], developed by academia, and the Hyundai intelligent Collision Avoidance Support System (HiCASS) testbed [24], developed by industry. Of the two, the eMIR platform is among those recognized by the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA), whereas the HiCASS testbed is not1. No testbeds targeting explicitly the INS were found. Limited information is available on the HiCASS testbed; its block diagram can be found in [24].