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In contrast, little information is available in the literature about legibility of multi-robot systems or swarms, where simplicity and non-anthropomorphism of robots, along with the complexity of their interactions and aggregated behavior impose different challenges that are not encountered in single-robot scenarios. This article investigates legibility of multi-robot systems. Hence, we extend the definition of legibility, incorporating information about high-level goals in terms of the coordination objective of the group of robots, to previous results that focused solely on the legibility of spatial goals. A set of standard multi-robot algorithms corresponding to different coordination objectives are implemented and their legibility is evaluated in a user study, where participants observe the behavior of the multi-robot system in a virtual reality setup and are asked to identify the system\u2019s spatial goal and coordination objective. The results of the study confirmed that coordination objectives are discernible by the users, hence multi-robot systems can be controlled to be legible, in terms of spatial goal and coordination objective.<\/jats:p>","DOI":"10.1145\/3647984","type":"journal-article","created":{"date-parts":[[2024,2,19]],"date-time":"2024-02-19T12:22:53Z","timestamp":1708345373000},"page":"1-32","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["Towards the Legibility of Multi-robot Systems"],"prefix":"10.1145","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2768-7557","authenticated-orcid":false,"given":"Beatrice","family":"Capelli","sequence":"first","affiliation":[{"name":"Department of Sciences and Methods for Engineering, University of Modena and Reggio Emilia, Reggio Emilia, Italy and System Logistics, Fiorano Modenese, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0897-9404","authenticated-orcid":false,"given":"Mar\u00eda","family":"Santos","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2734-5549","authenticated-orcid":false,"given":"Lorenzo","family":"Sabattini","sequence":"additional","affiliation":[{"name":"Department of Sciences and Methods for Engineering, University of Modena and Reggio Emilia, Reggio Emilia, Italy"}]}],"member":"320","published-online":{"date-parts":[[2024,6,14]]},"reference":[{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1109\/70.795787"},{"key":"e_1_3_4_3_2","doi-asserted-by":"publisher","DOI":"10.1109\/ROMAN.2016.7745188"},{"key":"e_1_3_4_4_2","doi-asserted-by":"publisher","DOI":"10.1007\/s11721-012-0075-2"},{"key":"e_1_3_4_5_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0921-8890(02)00373-1"},{"key":"e_1_3_4_6_2","first-page":"15","volume-title":"Proceedings of the International Workshop on Human-Friendly Robotics (HFR\u201919)","author":"Capelli Beatrice","year":"2019","unstructured":"Beatrice Capelli and Lorenzo Sabattini. 2019. 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