# UX in AR-Supported Industrial Human-Robot Collaborative Tasks: A Systematic Review
## 2 Methodology
### Search and Selection Process  
The search was conducted on the Scopus database, since it encompasses different digital libraries, such as IEEE or ACM, and provides high quality, indexed papers. The inclusion criteria are:  
* Typology: the study considers articles on international journals and papers on conference proceedings, or books;
* Topics: the study contains the keywords \"_augmented reality_\" + \"_human robot interaction_\" or \"_human robot collaboration_\" + \"_user experience_\" or \"_user interface_\". The search has been applied to \"Title\", \"Abstract\", and \"Keywords\" (TAK) fields. No reference to the \"Mixed Reality\" term was included since it subsumes both AR and VR;
* Year: the study has not been limited in terms of the publication year.  
According to [18], the following exclusion criteria have been defined:  
* Language: the paper is not written in English;
* Scope: the paper is out of scope and focuses on different research domain;
* Accessibility: the paper is not available.  
Seeing the high specificity of the \"_user experience_\" and \"_user interface_\" keywords, the initial search returned 27 papers. No secondary documents nor patents were found. No further papers' selections in terms of field of application of AR-supported collaborative tasks were provided, since the main interest is analyzing the current general sensibility towards the UX approaches.  
After the above-mentioned selection process, only 21 papers were admitted. The results from inclusion and exclusion criteria, and the number of papers found at each step, are shown in Table 1.  
Afterwards, the selected papers have been evaluated by a structured quality assessment procedure using three quality criteria (QC) similarly to [18]:  
* QC1: It reflects the quality of the journal on which the paper is published, where Qi refers to the quartile score, according to Scimago Journal Ranking [32]. A score of 1 was assigned to Q1 journals, 0.5 to Q2, and 0.25 to Q3. If the journal belongs to Q4, or if it does not belong to a specific quartile yet or it is part of a conference proceeding, a \"/\" is assigned counting as 0;  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Search String** & **Database** & **Date** & **Found** \\ \hline TITLE-ABS-KEY (augmented AND reality) AND & & & \\ (human AND robot AND interaction OR human & Scopus & 30/04/2021 & 27 \\ AND robot AND collaboration) AND (user AND & & & \\ experience OR user AND interface)) & & & \\ \hline \hline
**Exclusion Criteria** & & & \\ \hline Language & & & \\ Scope & & & 23 \\ Accessibility & & & 21 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Search and selection results.  
* QC2: It reflects the relevance of the specific paper. A value of 1 is assigned if the paper specifically has \"User Experience\", \"User Interface\", or \"Human-centered Design\" as one or more paper keywords. This choice was made to further understand if the paper was intended to be searchable for UX, HCD, or UI-related topics;
* QC3: It reflects the citation impact. It considers the number of total citations of the paper (_c_) compared to the maximum number of citations of the most cited paper (_mc_) among those included in the review. Certainly, this criterion will not be quantitatively relevant for the most recent works, but it helps to understand the most significant works as recognized from the scientific community. As a consequence, a final score ranging from 0 to 1 has been determined for each paper (_i_) included in the review: \[\text{QC3}(i)=c(i)/mc\]  
The final aim is to focus the review attention on papers which match at their best the intentions of the authors and to allow the reader to select the best referenced articles according to such criteria.