{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T18:08:55Z","timestamp":1779214135494,"version":"3.51.4"},"reference-count":40,"publisher":"Public Library of Science (PLoS)","issue":"5","license":[{"start":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T00:00:00Z","timestamp":1779148800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100017700","name":"Henan Province Science and Technology Research Project","doi-asserted-by":"crossref","award":["No.252102220033"],"award-info":[{"award-number":["No.252102220033"]}],"id":[{"id":"10.13039\/501100017700","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100010229","name":"Natural Science Foundation of Tianjin Municipal Science and Technology Commission","doi-asserted-by":"publisher","award":["No.252300420072"],"award-info":[{"award-number":["No.252300420072"]}],"id":[{"id":"10.13039\/501100010229","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004609","name":"Foundation of Henan Educational Committee","doi-asserted-by":"publisher","award":["No. 24A460023 and No. 26A460029"],"award-info":[{"award-number":["No. 24A460023 and No. 26A460029"]}],"id":[{"id":"10.13039\/501100004609","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Leachate grid clogging in waste-to-energy plants severely reduces combustion efficiency by up to 42% and may cause unplanned shutdowns, leading to substantial economic losses, necessitating automated cleaning solutions. However, gravity-induced elastic deformation in long-reach hydraulic manipulators limits their positioning precision. This research introduces an innovative feedforward static compensation strategy for hydraulically driven weak-rigid manipulators, which leverages detailed analytical joint stiffness modeling and avoids the inherent latency of conventional feedback-based methods (relying on force sensors or parameter identification); it is validated via comprehensive Adams multibody dynamics simulations. Validated via Adams multibody dynamics simulations, the proposed method reduced the end-effector positioning errors by 97.49% (X), 92.91% (Y), and 94.84% (Z), achieving a repeatable positioning accuracy of \u00b10.1 mm\u2014far exceeding the 0.5\u2009mm requirement for automated grid cleaning. This model-based compensation strategy provides a generalizable theoretical framework for precision control of long-reach hydraulic manipulators. The current study is validated through high-fidelity Adams simulations, achieving a simulated repeatable positioning accuracy of \u00b10.1\u2009mm. However, it is essential to emphasize that these results represent an idealized upper bound. Real-world hydraulic systems introduce complexities not captured in simulation\u2014including backlash, nonlinear friction, valve dynamics, hysteresis, leakage, and sensor quantization\u2014all of which will degrade practical accuracy. Therefore, this work establishes a theoretical foundation requiring experimental validation on physical hardware. Future work will focus on physical prototyping and on-site testing to address real-world challenges.<\/jats:p>","DOI":"10.1371\/journal.pone.0349592","type":"journal-article","created":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T17:33:07Z","timestamp":1779211987000},"page":"e0349592","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Gravity compensation for leachate grid cleaning robots in waste-to-energy plants: A modeling and simulation 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