{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T05:06:41Z","timestamp":1790140001884,"version":"4.0.1"},"reference-count":20,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T00:00:00Z","timestamp":1789776000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52204179"],"award-info":[{"award-number":["52204179"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["52204179"],"award-info":[{"award-number":["52204179"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Natural Science Foundation of Jiangsu Province","award":["BK20221128"],"award-info":[{"award-number":["BK20221128"]}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["2022M723395"],"award-info":[{"award-number":["2022M723395"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2022M723395"],"award-info":[{"award-number":["2022M723395"]}],"id":[{"id":"https:\/\/ror.org\/0426zh255","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Independent Research Project of State Key Laboratory of Intelligent Mining Equipment Technology"},{"name":"Priority Academic Program Development of Jiangsu Higher Education Institutions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Spatial interference among the shearer cutting drum, ranging arm, and hydraulic-support face guard is a practical safety risk in fully mechanized coal mining faces, where dust, water mist, weak illumination, and metal multipath reflections limit vision- and LiDAR-based perception. This study develops a 4D millimeter-wave radar point cloud sensing method for face guard segmentation and cutting-interference warning. Radar point clouds were extracted from ROS bag data, converted to frame-level point cloud files, manually labeled, and processed using a joint passthrough-radius filtering strategy. A PointNet++ semantic segmentation network was modified with radar feature augmentation and class-aware neighborhood sampling to identify sparse face guard points from background structures. The segmented face guard points were fitted by an axis-aligned 3D bounding box, and the minimum distance from shearer dangerous regions to the box was used to classify safe, warning, and dangerous states. On a 2160-frame labeled dataset, the final segmentation model reached 99.126% precision, 97.477% recall, and 96.608% IoU at epoch 100. Static pose, dust-condition, and dynamic sequence tests further verified that the proposed sensing pipeline can provide continuous face guard localization and distance-based interference monitoring under representative experimental conditions.<\/jats:p>","DOI":"10.3390\/s26185919","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T09:04:17Z","timestamp":1790067857000},"page":"5919","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["4D Millimeter-Wave Radar Point Cloud Sensing for Face Guard Detection and Cutting-Interference Warning in Fully Mechanized Coal Mining Faces"],"prefix":"10.3390","volume":"26","author":[{"given":"Yihui","family":"Zhao","sequence":"first","affiliation":[{"name":"School of Mechatronic Engineering, China University of Mining and Technology, No.1 Daxue Road, Xuzhou 221116, China"},{"name":"Xi\u2019an Coal Mining Machinery Co., Ltd., No.7 Jingpu Road, Gaoling District, Xi\u2019an 710200, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Zhongbin","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Mechatronic Engineering, China University of Mining and Technology, No.1 Daxue Road, Xuzhou 221116, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"}]},{"given":"Mo","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Mechatronic Engineering, China University of Mining and Technology, No.1 Daxue Road, Xuzhou 221116, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"software","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8616-2040","authenticated-orcid":false,"given":"Dong","family":"Wei","sequence":"additional","affiliation":[{"name":"School of Mechatronic Engineering, China University of Mining and Technology, No.1 Daxue Road, Xuzhou 221116, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,19]]},"reference":[{"key":"ref_1","unstructured":"Man, Y. 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