{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T08:31:03Z","timestamp":1786437063603,"version":"build-2736575974"},"reference-count":33,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T00:00:00Z","timestamp":1786406400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Polar Environment Perception and Image Analysis Technology Fund","award":["YDZX20263100004015004"],"award-info":[{"award-number":["YDZX20263100004015004"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, an improved fixed-width histogram (IFWH) algorithm with multi-strategy enhancement is proposed for simulation-based AUV path planning in complex underwater environments. A multi-constraint optimization framework considering propulsion energy consumption, obstacle threats, terrain collision risks, and maneuverability constraints is established. Chaotic population initialization, adaptive global\u2013local search transfer, quadratic interpolation, and spiral local refinement are integrated to enhance population diversity and trajectory smoothness. Numerical simulations are conducted under current-free terrains, overlapping seabed-current conditions, and environments with static and dynamic obstacles. Compared with A*, FWH, IPSO, and SVF-RRT*, IFWH reduces the average terrain slope by 43.91%, 47.24%, 44.94%, and 43.71%, respectively, and decreases estimated propulsion energy consumption by 35.29%, 37.38%, 24.66%, and 35.93% in current-free Scenario A. Under overlapping seabed-current conditions, IFWH achieves a 100% success rate over 30 independent trials, obtaining average slope angles of 15.58\u00b0 and 18.73\u00b0 with propulsion energy costs of 1163.57 J and 1116.99 J, respectively. In mixed environments, all trials are completed without collision, with average planning times of 1.674\u00a00.700\u00a0s and 0.692\u00b10.053\u00a0s under following- and rotary-current conditions, respectively.<\/jats:p>","DOI":"10.3390\/s26165079","type":"journal-article","created":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T08:09:36Z","timestamp":1786435776000},"page":"5079","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Improved FWH Path-Planning Algorithm Based on Multi-Strategy Enhancement for AUVs Operating in Coral Reef Areas"],"prefix":"10.3390","volume":"26","author":[{"given":"Qingjun","family":"Zeng","sequence":"first","affiliation":[{"name":"School of Automation, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-7590-4380","authenticated-orcid":false,"given":"Xiao","family":"Feng","sequence":"additional","affiliation":[{"name":"School of Automation, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hewei","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Automation, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoqiang","family":"Dai","sequence":"additional","affiliation":[{"name":"School of Automation, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yifeng","family":"Han","sequence":"additional","affiliation":[{"name":"School of Automation, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,11]]},"reference":[{"key":"ref_1","first-page":"287","article-title":"Development of sea glider autonomous underwater vehicle platform for marine exploration and monitoring","volume":"40","author":"Sagala","year":"2011","journal-title":"Indian J. Mar. Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"109355","DOI":"10.1016\/j.oceaneng.2021.109355","article-title":"Path planning and obstacle avoidance for AUV: A review","volume":"235","author":"Cheng","year":"2021","journal-title":"Ocean Eng."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1038\/nature21707","article-title":"Global warming and recurrent mass bleaching of corals","volume":"543","author":"Hughes","year":"2017","journal-title":"Nature"},{"key":"ref_4","unstructured":"Spady, B.L., Skirving, W.J., and De la Cour, J.L. (2025, July 02). The 4th Global Coral Bleaching Event: Unprecedented, Unbounded, Unrelenting. Available online: https:\/\/eartharxiv.org\/repository\/object\/9564\/download\/17821\/."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"109472","DOI":"10.1016\/j.oceaneng.2021.109472","article-title":"An abnormal motion condition monitoring method based on the dynamic model and complex network for AUV","volume":"237","author":"Gao","year":"2021","journal-title":"Ocean Eng."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"113263","DOI":"10.1016\/j.oceaneng.2022.113263","article-title":"Collision avoidance control for unmanned surface vehicle with COLREGs compliance","volume":"267","author":"Sun","year":"2023","journal-title":"Ocean Eng."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Chen, Z., Yan, J., Huang, R., Gao, Y., Peng, X., and Yuan, W. (2024). Path Planning for Autonomous Underwater Vehicles (AUVs) Considering the Influences and Constraints of Ocean Currents. Drones, 8.","DOI":"10.3390\/drones8080348"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"29953","DOI":"10.1109\/JSEN.2025.3580629","article-title":"Enhancing Underwater Wireless Sensor Network Lifetime: An Energy-Aware AUV-Assisted Data Collection Scheme","volume":"25","author":"Tang","year":"2025","journal-title":"IEEE Sens. J."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Qin, H., Shao, S., Wang, T., Yu, X., Jiang, Y., and Cao, Z. (2023). Review of Autonomous Path Planning Algorithms for Mobile Robots. Drones, 7.","DOI":"10.3390\/drones7030211"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1016\/j.knosys.2018.05.033","article-title":"Survey on computational-intelligence-based UAV path planning","volume":"158","author":"Zhao","year":"2018","journal-title":"Knowl. Based Syst."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1564","DOI":"10.1016\/j.compeleceng.2012.06.016","article-title":"Dynamic path planning of mobile robots with improved genetic algorithm","volume":"38","author":"Tuncer","year":"2012","journal-title":"Comput. Electr. Eng."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Li, Q., Zhang, W., Yin, Y., Wang, Z., and Liu, G. (2006, January 16\u201318). An improved genetic algorithm of optimum path planning for mobile robots. Proceedings of the Sixth International Conference on Intelligent Systems Design and Applications, Jinan, China.","DOI":"10.1109\/ISDA.2006.253911"},{"key":"ref_13","unstructured":"Hu, Y., and Yang, S.X. (May, January 26). A knowledge based genetic algorithm for path planning of a mobile robot. Proceedings of the 2004 IEEE International Conference on Robotics and Automation, New Orleans, LA, USA."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"147","DOI":"10.5772\/58872","article-title":"Robil: Robot path planning based on pbil algorithm","volume":"11","author":"Kang","year":"2014","journal-title":"Int. J. Adv. Rob. Syst."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"854","DOI":"10.23919\/JSEE.2025.000074","article-title":"AUV 3D path planning based on improved PSO","volume":"36","author":"Li","year":"2025","journal-title":"J. Syst. Eng. Electron."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Tian, Q., Wang, T., Yang, Y., Li, C., and Liu, B. (2022). Robust Optimization Design for Path Planning of Bionic Robotic Fish in the Presence of Ocean Currents. J. Mar. Sci. Eng., 10.","DOI":"10.3390\/jmse10081109"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"4269","DOI":"10.1016\/j.jksuci.2020.10.010","article-title":"Domain knowledge based genetic algorithms for mobile robot path planning having single and multiple targets","volume":"34","author":"Sarkar","year":"2022","journal-title":"J. King Saud Univ. Comput. Inf. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"119977","DOI":"10.1016\/j.ins.2023.119977","article-title":"A multi-objective evolutionary algorithm based on dimension exploration and discrepancy evolution for UAV path planning problem","volume":"657","author":"Xu","year":"2024","journal-title":"Inf. Sci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"106773","DOI":"10.1016\/j.compeleceng.2020.106773","article-title":"Obstacle avoidance path planning of unmanned submarine vehicle in ocean current environment based on improved firework-ant colony algorithm","volume":"87","author":"Ma","year":"2020","journal-title":"Comput. Electr. Eng."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"42904","DOI":"10.1109\/ACCESS.2018.2861468","article-title":"Three-Dimensional Path Planning for AUV Based on Interfered Fluid Dynamical System Under Ocean Current","volume":"6","author":"Yao","year":"2018","journal-title":"IEEE Access"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1109\/TIV.2022.3153352","article-title":"Path Planning Based on Deep Reinforcement Learning for Autonomous Underwater Vehicles Under Ocean Current Disturbance","volume":"8","author":"Chu","year":"2023","journal-title":"IEEE Trans. Intell. Veh."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1109\/TIV.2021.3082151","article-title":"Bio-Inspired Neural Network-Based Optimal Path Planning for UUVs Under the Effect of Ocean Currents","volume":"7","author":"Zhu","year":"2022","journal-title":"IEEE Trans. Intell. Veh."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2413","DOI":"10.1109\/LRA.2023.3245409","article-title":"SVF-RRT*: A Stream-Based VF-RRT* for USVs Path Planning Considering Ocean Currents","volume":"8","author":"Zhang","year":"2023","journal-title":"IEEE Robot. Autom. Lett."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"31010","DOI":"10.1109\/ACCESS.2023.3257025","article-title":"Path planning for autonomous underwater vehicles based on an improved artificial jellyfish search algorithm in multi-obstacle ocean current environment","volume":"11","author":"Guo","year":"2023","journal-title":"IEEE Access"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"119260","DOI":"10.1016\/j.oceaneng.2024.119260","article-title":"A novel robust algorithm for path planning of multiple autonomous underwater vehicles in the environment with ocean currents","volume":"312","author":"Yin","year":"2024","journal-title":"Ocean. Eng."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"853","DOI":"10.1016\/j.robot.2013.04.002","article-title":"Coordination control of underactuated ODINs in three-dimensional space","volume":"61","author":"Do","year":"2013","journal-title":"Robot. Auton. Syst."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1109\/9.739086","article-title":"Time-varying exponential stabilization of the position and attitude of an underactuated autonomous underwater vehicle","volume":"44","author":"Pettersen","year":"1999","journal-title":"IEEE Trans. Autom. Control"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"110950","DOI":"10.1016\/j.ast.2025.110950","article-title":"Dynamic UAV path planning in mountainous terrain utilizing an arithmetic optimization algorithm incorporating adaptive thermal conduction search and elite population genetic strategies","volume":"168","author":"Wang","year":"2026","journal-title":"Aerosp. Sci. Technol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"196","DOI":"10.1016\/j.isatra.2024.04.010","article-title":"Three-dimensional unmanned aerial vehicle path planning utilizing artificial gorilla troops optimizer incorporating combined mutation and quadratic interpolation operators","volume":"149","author":"Ye","year":"2024","journal-title":"ISA Trans."},{"key":"ref_30","first-page":"1050","article-title":"Evolutionary algorithm using marginal histogram models in continuous domain","volume":"2001019","author":"Tsutsui","year":"2001","journal-title":"IlliGAL Rep."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.optlaseng.2015.09.007","article-title":"A novel bit-level image encryption algorithm based on chaotic maps","volume":"78","author":"Xu","year":"2016","journal-title":"Opt. Lasers Eng."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"9003","DOI":"10.1109\/TVT.2023.3348140","article-title":"An Efficient and Accurate A-Star Algorithm for Autonomous Vehicle Path Planning","volume":"73","author":"Lin","year":"2024","journal-title":"IEEE Trans. Veh. Technol."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Fan, X., Xue, C., and Zhou, H. (2022, January 25\u201327). Research on UUV path planning method based on bidirectional A* algorithm. Proceedings of the 2022 China Automation Congress (CAC), Xiamen, China.","DOI":"10.1109\/CAC57257.2022.10055859"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/26\/16\/5079\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T08:15:03Z","timestamp":1786436103000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/26\/16\/5079"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,11]]},"references-count":33,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["s26165079"],"URL":"https:\/\/doi.org\/10.3390\/s26165079","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,11]]}}}