Waist rotation angle as indicator of probable human collision-avoidance direction for autonomous mobile robots

Tatsuto Yamauchi; Hideki Tamura; Tetsuto Minami; Shigeki Nakauchi

doi:10.1371/journal.pone.0323632

Peer Review History

Original SubmissionSeptember 20, 2024
20 Sep 2024 Author Response Attachments Attachment Submitted filename: Yamauchi_mobility_response_R2_20240918.docx https://doi.org/10.1371/journal.pone.0323632.r001
29 Jan 2025 Decision Letter - silas onyango awuor, Editor PONE-D-24-41357Waist rotation angle as an indicator of probable human collision avoidance direction for autonomous mobile robotsPLOS ONE Dear Dr. Tamura, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Mar 15 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. 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The PLOS ONE style templates can be found at https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf . 2. Thank you for stating in your Funding Statement: “This paper is based on the results from project JPNP20004, subsidized by the New Energy and Industrial Technology Development Organization (NEDO). This work was supported by the CASIO SCIENCE PROMOTION FOUNDATION (39-55) funds, the Foundation of Public Interest of Tatematsu, and the 2021 Toyohashi University of Technology President Funding (Young Researchers).” Please provide an amended statement that declares all the funding or sources of support (whether external or internal to your organization) received during this study, as detailed online in our guide for authors at http://journals.plos.org/plosone/s/submit-now. 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We will only publish funding information present in the Funding Statement section of the online submission form. Please remove any funding-related text from the manuscript and let us know how you would like to update your Funding Statement. Currently, your Funding Statement reads as follows: “This paper is based on the results from project JPNP20004, subsidized by the New Energy and Industrial Technology Development Organization (NEDO). This work was supported by the CASIO SCIENCE PROMOTION FOUNDATION (39-55) funds, the Foundation of Public Interest of Tatematsu, and the 2021 Toyohashi University of Technology President Funding (Young Researchers).” Please include your amended statements within your cover letter; we will change the online submission form on your behalf. 4. Please remove your figures from within your manuscript file, leaving only the individual TIFF/EPS image files, uploaded separately. These will be automatically included in the reviewers’ PDF 5. Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. Additional Editor Comments (if provided): Kindly act on the raised comments [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes ****** 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes ****** 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: This paper presents a series of experiments to study the interaction between AMR and human participants. The authors conducted three experiments to develop a method for collision avoidance that would be well perceived by human participants. In the first experiment human participants had to walk against AMR coming from different angles to study which behavior of human participants can hint for future actions. In particular, the authors intended to study whether it is possible to predict the direction in which people would move to avoid the AMR. Results showed that waist rotation occurs slightly before the actual steering maneuver and can therefore be used as a predictor for avoidance direction. Based on these results the authors implemented a collision avoidance algorithm in the robot and tested it in experiments. In the first experiment data from motion tracker on human were used to guide the robot. However, since this would not possible in reality the authors later also tested another method using information gained from a sensor on the robot. Results show that participants prefer an early steering maneuver from the robot and judge it more “comfortable.” The paper is interesting and well presented. All details needed for reproducing the findings are provided and literature review is generally complete and satisfactory. The structure follows a logical structure in which exploratory experiments are presented first and implementation based on the results follow to show how the authors intend to make their solution usable in reality. However, I must admit I found the paper quite verbose. I understand that providing all details is important, but sometimes I found the amount of information overwhelming. For example (but it is not the only one), Fig. 6 contains all the value for the scale which is also reported in the text. I believe something like “from very fast to very slow” or “from very uncomfortable to very comfortable” would be enough. Also, much of the text in the discussion can be found in the presentation of the results. The fact that waist rotation can predict avoidance direction is repeated a large number of times in the manuscript and I am not sure whether it is really important to stress on something that is already clear when results are presented. Since this already the second review of this manuscript and I do not see the verbosity as an obstacle for publication (the paper is good, so for me can be published with minimal modification), I do not want to force the authors into an extensive round of review. Nonetheless, I believe that making the paper more “compact” can help them making it readable to a larger audience. For this reason I want to give a chance to the authors to review their paper, but I also want to make it clear it is not a condition for acceptance. As a personal suggestion I would propose to only keep the aspects related to the experiment in the main text and move all minor technical details to an appendix. For example, average age of the participants, date of the experiment, ethical approval, OS and model of the robot, CV tool used, etc. can be moved to an appendix. I think they are not really relevant to understand the experiments and are only needed in case someone want to reproduce it (so they must be kept, but probably not in the main text). Some additional comments are given as follows: 1. Abstract: Readers cannot know that is your Experiment 2 and 3 so I suggest removing them. Also, since only experiments 2 and 3 are mentioned, one would wonder where it Experiment 1. Of course, that is clear in the manuscript, but abstract is read before the main text. 2. Fig. 5: I found if difficult to understand and generally not standalone. Maybe you can consider providing a number of snapshots, like in the old animation movies. Or use colors to show the change in time. For example, as robot and person move toward each other the color gets brighter (black, dark gray, light gray, etc.). b is also not that clear. The angle of the arrow changes a little, making it difficult to understand. What about using a top view where a person is moving the waist? In c I found “slower” and “more comfortable” redundant and creating more confusion. 3. Fig. 6: As already said, I found the reporting of the scale here redundant. 4. Fig. 7: I believe you are using MATLAB. If so, why don’t you use unwrap to “join” the angles and avoid the jump from 0 to 360? You can have negative values and the graphs looks clearer. The jump you see looks like there is some data loss or something strange happened, while in reality is simply related to the definition of the angle. 5. As already mentioned I do not want to force you into an additional work. I genuinely believe that the two papers below are related to your work, so maybe you can find them useful for this paper or in a follow-up study. Jia, Xiaolu, et al. "Experimental study on the evading behavior of individual pedestrians when confronting with an obstacle in a corridor." Physica A: Statistical Mechanics and its Applications 531 (2019): 121735. Murakami, Hisashi, et al. "Spontaneous behavioral coordination between avoiding pedestrians requires mutual anticipation rather than mutual gaze." Iscience 25.11 (2022). ****** 6. PLOS authors have the option to publish the peer review history of their article (what does this mean? ). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy . Reviewer #1: Yes: Claudio Feliciani ******** [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/ . PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org . Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0323632.r002
Revision 1
8 Feb 2025 Author Response Response Letter We thank the editor and reviewers for their time and effort in reviewing our manuscript. The changes we have implemented based on their insightful comments, suggestions, and feedback have significantly improved our work. We have made revisions to strengthen the manuscript. Additionally, we utilized a professional English language editing service to improve the language quality of the manuscript. Detailed responses to the reviewers’ comments are provided below. Reviewer #1: This paper presents a series of experiments to study the interaction between AMR and human participants. The authors conducted three experiments to develop a method for collision avoidance that would be well perceived by human participants. In the first experiment human participants had to walk against AMR coming from different angles to study which behavior of human participants can hint for future actions. In particular, the authors intended to study whether it is possible to predict the direction in which people would move to avoid the AMR. Results showed that waist rotation occurs slightly before the actual steering maneuver and can therefore be used as a predictor for avoidance direction. Based on these results the authors implemented a collision avoidance algorithm in the robot and tested it in experiments. In the first experiment data from motion tracker on human were used to guide the robot. However, since this would not possible in reality the authors later also tested another method using information gained from a sensor on the robot. Results show that participants prefer an early steering maneuver from the robot and judge it more “comfortable.” Thank you for summarizing our manuscript. The paper is interesting and well presented. All details needed for reproducing the findings are provided and literature review is generally complete and satisfactory. The structure follows a logical structure in which exploratory experiments are presented first and implementation based on the results follow to show how the authors intend to make their solution usable in reality. Thank you very much for your positive feedback. However, I must admit I found the paper quite verbose. I understand that providing all details is important, but sometimes I found the amount of information overwhelming. For example (but it is not the only one), Fig. 6 contains all the value for the scale which is also reported in the text. I believe something like “from very fast to very slow” or “from very uncomfortable to very comfortable” would be enough. Thank you for your specific feedback. We have simplified the y-axis label and caption in Figs. 6 and 8. Also, much of the text in the discussion can be found in the presentation of the results. The fact that waist rotation can predict avoidance direction is repeated a large number of times in the manuscript and I am not sure whether it is really important to stress on something that is already clear when results are presented. Thank you for your feedback. We have revised the discussion to eliminate redundancy with the results section. Since this already the second review of this manuscript and I do not see the verbosity as an obstacle for publication (the paper is good, so for me can be published with minimal modification), I do not want to force the authors into an extensive round of review. Nonetheless, I believe that making the paper more “compact” can help them making it readable to a larger audience. For this reason I want to give a chance to the authors to review their paper, but I also want to make it clear it is not a condition for acceptance. Thank you for your comments. As you suggested, we have eliminated redundant sentences. Additionally, we used an English proofreading service to ensure the coherence and flow of the text remain intact. As a personal suggestion I would propose to only keep the aspects related to the experiment in the main text and move all minor technical details to an appendix. For example, average age of the participants, date of the experiment, ethical approval, OS and model of the robot, CV tool used, etc. can be moved to an appendix. I think they are not really relevant to understand the experiments and are only needed in case someone want to reproduce it (so they must be kept, but probably not in the main text). Thank you for your suggestion. As you mentioned, we have reduced the main text in the Methods section and moved minor technical details to the Appendix to make the paper more concise. Specifically, parts of the Participants and Apparatus sections have been relocated. However, for Figs. 5 and 7, which illustrate the methodology, we retained the relevant descriptions in the main text to maintain consistency with the figure explanations, minimizing the information moved to the Appendix. Some additional comments are given as follows: 1. Abstract: Readers cannot know that is your Experiment 2 and 3 so I suggest removing them. Also, since only experiments 2 and 3 are mentioned, one would wonder where it Experiment 1. Of course, that is clear in the manuscript, but abstract is read before the main text. Thank you for your feedback. As you suggested, we have removed explicit references to Experiment 2 and Experiment 3 from the abstract to improve readability. 2. Fig. 5: I found if difficult to understand and generally not standalone. Maybe you can consider providing a number of snapshots, like in the old animation movies. Or use colors to show the change in time. For example, as robot and person move toward each other the color gets brighter (black, dark gray, light gray, etc.). b is also not that clear. The angle of the arrow changes a little, making it difficult to understand. What about using a top view where a person is moving the waist? In c I found “slower” and “more comfortable” redundant and creating more confusion. Thank you for your suggestion. We have revised Fig. 5 as follows: Fig. 5a: As you suggested, we illustrated the progression from the beginning to the end of a trial using snapshots from a video. Fig. 5b: We clarified the movement of the participants’ waist by using a schematic top-down view, showing the changes in the waist angle (θ) for each condition (Beginning, Early, Same, Late). Fig. 5c: We simplified the labels to improve readability. 3. Fig. 6: As already said, I found the reporting of the scale here redundant. As mentioned above, we have revised the y-axis label and caption in Figs. 6 and 8. 4. Fig. 7: I believe you are using MATLAB. If so, why don’t you use unwrap to “join” the angles and avoid the jump from 0 to 360? You can have negative values and the graphs looks clearer. The jump you see looks like there is some data loss or something strange happened, while in reality is simply related to the definition of the angle. Thank you for your suggestion. We applied the unwrap function in MATLAB to ensure a continuous representation of the angle without jumps. This adjustment makes Fig. 7 clearer and prevents any misinterpretation related to data loss or anomalies. 5. As already mentioned I do not want to force you into an additional work. I genuinely believe that the two papers below are related to your work, so maybe you can find them useful for this paper or in a follow-up study. Jia, Xiaolu, et al. "Experimental study on the evading behavior of individual pedestrians when confronting with an obstacle in a corridor." Physica A: Statistical Mechanics and its Applications 531 (2019): 121735. Murakami, Hisashi, et al. "Spontaneous behavioral coordination between avoiding pedestrians requires mutual anticipation rather than mutual gaze." Iscience 25.11 (2022). Thank you for your suggestion. As you mentioned, the recommended papers are highly relevant to our manuscript, so we cited them in the main text (Murakami et al., 2022 in Literature review; Jia et al., 2019 in Discussion). We appreciate your insightful feedback. Once again, we appreciate the opportunity to revise our manuscript based on the reviewers’ valuable input. We look forward to hearing from you regarding our submission and will be happy to respond should you have any further questions or comments. Sincerely, Tatsuto Yamauchi, Hideki Tamura, Tetsuto Minami, and Shigeki Nakauchi Attachments Attachment Submitted filename: Yamauchi_mobility_response_R3_20250209.docx https://doi.org/10.1371/journal.pone.0323632.r003
11 Feb 2025 Decision Letter - silas onyango awuor, Editor PONE-D-24-41357R1Waist rotation angle as indicator of probable human collision-avoidance direction for autonomous mobile robotsPLOS ONE Dear Dr. Tamura, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Some additional comments are given as follows: 1. Abstract: Readers cannot know that is your Experiment 2 and 3 so I suggest removing them. Also, since only experiments 2 and 3 are mentioned, one would wonder where it Experiment 1. Of course, that is clear in the manuscript, but abstract is read before the main text. 2. Fig. 5: I found if difficult to understand and generally not standalone. Maybe you can consider providing a number of snapshots, like in the old animation movies. Or use colors to show the change in time. For example, as robot and person move toward each other the color gets brighter (black, dark gray, light gray, etc.). b is also not that clear. The angle of the arrow changes a little, making it difficult to understand. What about using a top view where a person is moving the waist? In c I found “slower” and “more comfortable” redundant and creating more confusion. 3. Fig. 6: As already said, I found the reporting of the scale here redundant. 4. Fig. 7: I believe you are using MATLAB. If so, why don’t you use unwrap to “join” the angles and avoid the jump from 0 to 360? You can have negative values and the graphs looks clearer. The jump you see looks like there is some data loss or something strange happened, while in reality is simply related to the definition of the angle. 5. As already mentioned I do not want to force you into an additional work. I genuinely believe that the two papers below are related to your work, so maybe you can find them useful for this paper or in a follow-up study. Jia, Xiaolu, et al. "Experimental study on the evading behavior of individual pedestrians when confronting with an obstacle in a corridor." Physica A: Statistical Mechanics and its Applications 531 (2019): 121735. Murakami, Hisashi, et al. "Spontaneous behavioral coordination between avoiding pedestrians requires mutual anticipation rather than mutual gaze." Iscience 25.11 (2022). Please submit your revised manuscript by Mar 28 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols . We look forward to receiving your revised manuscript. Kind regards, silas onyango awuor, msc Academic Editor PLOS ONE Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. Additional Editor Comments: congratulation for the input otherwise I realized that the reviewer comments is not well answered kindly take you time and act on the below comments. Some additional comments are given as follows: 1. Abstract: Readers cannot know that is your Experiment 2 and 3 so I suggest removing them. Also, since only experiments 2 and 3 are mentioned, one would wonder where it Experiment 1. Of course, that is clear in the manuscript, but abstract is read before the main text. 2. Fig. 5: I found if difficult to understand and generally not standalone. Maybe you can consider providing a number of snapshots, like in the old animation movies. Or use colors to show the change in time. For example, as robot and person move toward each other the color gets brighter (black, dark gray, light gray, etc.). b is also not that clear. The angle of the arrow changes a little, making it difficult to understand. What about using a top view where a person is moving the waist? In c I found “slower” and “more comfortable” redundant and creating more confusion. 3. Fig. 6: As already said, I found the reporting of the scale here redundant. 4. Fig. 7: I believe you are using MATLAB. If so, why don’t you use unwrap to “join” the angles and avoid the jump from 0 to 360? You can have negative values and the graphs looks clearer. The jump you see looks like there is some data loss or something strange happened, while in reality is simply related to the definition of the angle. 5. As already mentioned I do not want to force you into an additional work. I genuinely believe that the two papers below are related to your work, so maybe you can find them useful for this paper or in a follow-up study. Jia, Xiaolu, et al. "Experimental study on the evading behavior of individual pedestrians when confronting with an obstacle in a corridor." Physica A: Statistical Mechanics and its Applications 531 (2019): 121735. Murakami, Hisashi, et al. "Spontaneous behavioral coordination between avoiding pedestrians requires mutual anticipation rather than mutual gaze." Iscience 25.11 (2022). [Note: HTML markup is below. Please do not edit.] [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/ . PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org . Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0323632.r004
Revision 2
11 Feb 2025 Author Response Response Letter congratulation for the input otherwise I realized that the reviewer comments is not well answered kindly take you time and act on the below comments. Thank you for reaching out to us. As outlined below, we have made the necessary revisions. We kindly ask for your review and confirmation. Some additional comments are given as follows: 1. Abstract: Readers cannot know that is your Experiment 2 and 3 so I suggest removing them. Also, since only experiments 2 and 3 are mentioned, one would wonder where it Experiment 1. Of course, that is clear in the manuscript, but abstract is read before the main text. Thank you for your feedback. As you suggested, we have removed explicit references to Experiment 2 and Experiment 3 from the abstract to improve readability. 2. Fig. 5: I found if difficult to understand and generally not standalone. Maybe you can consider providing a number of snapshots, like in the old animation movies. Or use colors to show the change in time. For example, as robot and person move toward each other the color gets brighter (black, dark gray, light gray, etc.). b is also not that clear. The angle of the arrow changes a little, making it difficult to understand. What about using a top view where a person is moving the waist? In c I found “slower” and “more comfortable” redundant and creating more confusion. Thank you for your suggestion. We have revised Fig. 5 as follows: Fig. 5a: As you suggested, we illustrated the progression from the beginning to the end of a trial using snapshots from a video. Fig. 5b: We clarified the movement of the participants’ waist by using a schematic top-down view, showing the changes in the waist angle (θ) for each condition (Beginning, Early, Same, Late). Fig. 5c: We simplified the labels to improve readability. 3. Fig. 6: As already said, I found the reporting of the scale here redundant. We have revised the y-axis label and caption in Figs. 6 and 8. 4. Fig. 7: I believe you are using MATLAB. If so, why don’t you use unwrap to “join” the angles and avoid the jump from 0 to 360? You can have negative values and the graphs looks clearer. The jump you see looks like there is some data loss or something strange happened, while in reality is simply related to the definition of the angle. Thank you for your suggestion. We applied the unwrap function in MATLAB to ensure a continuous representation of the angle without jumps. This adjustment makes Fig. 7 clearer and prevents any misinterpretation related to data loss or anomalies. 5. As already mentioned I do not want to force you into an additional work. I genuinely believe that the two papers below are related to your work, so maybe you can find them useful for this paper or in a follow-up study. Jia, Xiaolu, et al. "Experimental study on the evading behavior of individual pedestrians when confronting with an obstacle in a corridor." Physica A: Statistical Mechanics and its Applications 531 (2019): 121735. Murakami, Hisashi, et al. "Spontaneous behavioral coordination between avoiding pedestrians requires mutual anticipation rather than mutual gaze." Iscience 25.11 (2022). Thank you for your suggestion. As you mentioned, the recommended papers are highly relevant to our manuscript, so we cited them in the main text (Murakami et al., 2022 in Literature review; Jia et al., 2019 in Discussion). We appreciate your insightful feedback. Once again, we appreciate the opportunity to revise our manuscript based on the reviewers’ valuable input. We look forward to hearing from you regarding our submission and will be happy to respond should you have any further questions or comments. Sincerely, Tatsuto Yamauchi, Hideki Tamura, Tetsuto Minami, and Shigeki Nakauchi Attachments Attachment Submitted filename: Yamauchi_mobility_response_R3_20250212.docx https://doi.org/10.1371/journal.pone.0323632.r005
6 Apr 2025 Decision Letter - Dimitris Voudouris, Editor PONE-D-24-41357R2Waist rotation angle as indicator of probable human collision-avoidance direction for autonomous mobile robotsPLOS ONE Dear Dr. Tamura, Thank you for submitting your manuscript to PLOS ONE. The reviewer who evaluated your manuscript has deemed it suitable for publication but I noticed two minor issues that I would like you to consider before an Accept desicion can be made. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by May 21 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols . We look forward to receiving your revised manuscript. Kind regards, Dimitris Voudouris Academic Editor PLOS ONE Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. 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Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0323632.r006
Revision 3
8 Apr 2025 Author Response Response Letter The term PSE (e.g., line 264 and elsewhere) is not appropriate as the term "subjective equality" is not well aligned with your analysis. I recommend revising it to something else. Given that your x-axis in Figure 3B indicats the robot's starting angle, you could use this term instead. Thank you for pointing this out. We agree that the term “PSE” may not precisely reflect the nature of our analysis. In response to your suggestion, we have replaced it with either “starting angle” or “estimated starting angle,” depending on the context throughout the manuscript, including the caption of Figure 3B and the relevant sections in the main text. Lines 316–317, consider using numbers ("reached 1 and 1.5 times the average range.."). Thank you for your suggestion. We have revised the sentence to use numeric expressions for clarity. “In the Early and Late conditions, the AMR initiated deflection when the participant’s waist rotation angle reached 0.5 and 1.5 times the average range of waist rotation angles, respectively.” Attachments Attachment Submitted filename: Yamauchi_mobility_response_R4_20250407.docx https://doi.org/10.1371/journal.pone.0323632.r007
11 Apr 2025 Decision Letter - Dimitris Voudouris, Editor Waist rotation angle as indicator of probable human collision-avoidance direction for autonomous mobile robots PONE-D-24-41357R3 Dear Dr. Tamura, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Dimitris Voudouris Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: https://doi.org/10.1371/journal.pone.0323632.r008
Formally Accepted
Acceptance Letter - Dimitris Voudouris, Editor PONE-D-24-41357R3 PLOS ONE Dear Dr. Tamura, I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team. At this stage, our production department will prepare your paper for publication. This includes ensuring the following: * All references, tables, and figures are properly cited * All relevant supporting information is included in the manuscript submission, * There are no issues that prevent the paper from being properly typeset You will receive further instructions from the production team, including instructions on how to review your proof when it is ready. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few days to review your paper and let you know the next and final steps. Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. If we can help with anything else, please email us at customercare@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Dimitris Voudouris Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0323632.r009

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