A hierarchical QP optimization control strategy for quadruped robots facing a variety of structural terrains

A hierarchical QP optimization control strategy for quadruped robots facing a variety of structural terrains | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article A hierarchical QP optimization control strategy for quadruped robots facing a variety of structural terrains Chikun Gong, XiaoLong Jin, Lipeng Yuan, Na zhang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6704764/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Addressing the dynamic stability issue of quadruped robots with a relatively high proportion of leg mass in various structured terrains, this paper proposes a hybrid control strategy. Initially, the gait scheduling framework is constructed using Hopf oscillators within the Central Pattern Generator (CPG) to emulate the bio-inspired characteristics of quadruped robot locomotion. Subsequently, terrain estimation and gait planning are employed to enable the robot to traverse diverse structured terrains. During the stance phase of quadruped robot locomotion, a hierarchical quadratic programming (QP) optimization control is implemented. In the swing phase, a force-based impedance control is adopted to enhance the compliance and smoothness of the robot's leg-lifting motion. Furthermore, by leveraging Lyapunov stability theory, the stability of the control system in the swing phase is rigorously analyzed and proven, thereby ensuring the effectiveness and reliability of the control strategy from a theoretical standpoint. For posture control, dynamic stability is achieved by adjusting the linear and angular accelerations of the robot's center of mass. The proposed control strategy was validated through the MATLAB/Simulink simulation platform. The results demonstrate that, compared with the standard QP optimization control, the proposed strategy can more accurately and stably control the quadruped robot's locomotion on flat ground. Moreover, the strategy enables the robot to achieve stable walking on various structured terrains. Quadruped robot Gait scheduling based on CPG Terrain estimation Footfall planning Hierarchical QP optimization control Impedance control Full Text Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6704764","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":460969671,"identity":"a0c01f12-1fa8-46ac-a540-43e16be539d8","order_by":0,"name":"Chikun Gong","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Chikun","middleName":"","lastName":"Gong","suffix":""},{"id":460969672,"identity":"f764b474-19de-47e5-90a4-e36b70df52ca","order_by":1,"name":"XiaoLong Jin","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"XiaoLong","middleName":"","lastName":"Jin","suffix":""},{"id":460969673,"identity":"4bccb39d-6680-4fd2-8957-47276bb7a616","order_by":2,"name":"Lipeng Yuan","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAq0lEQVRIiWNgGAWjYBACA2Yg8YDBhoefvYFoLUA9CQxpMpI9B4jVwgDWctjG4IYDkVrM2fmPSSTuOM/DcIOB8cPHHCK0WDYzs0kknrnNwzi7gVly5jZiHHYYpKXtNg+zzAE2Zl4StJzjYZNIIE3LAR4eUrQYWySeSeaR4DnYTKRfzh98eOPjDjt7++PNBz98JEYLELBIMDaAaAhJFGD+QILiUTAKRsEoGIkAACftMqhW3g+0AAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0003-0324-5065","institution":"Harbin Institute of Technology","correspondingAuthor":true,"prefix":"","firstName":"Lipeng","middleName":"","lastName":"Yuan","suffix":""},{"id":460969674,"identity":"420992b2-235f-406e-ab23-8094f29adc65","order_by":3,"name":"Na zhang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Na","middleName":"","lastName":"zhang","suffix":""}],"badges":[],"createdAt":"2025-05-20 07:14:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6704764/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6704764/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":85468351,"identity":"816c0367-fbbf-4e36-a226-2d9105ed1998","added_by":"auto","created_at":"2025-06-26 08:53:13","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1061488,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript68.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6704764/v1_covered_3ca1e2d6-a9d5-4815-9033-9fb44aa74887.pdf"}],"financialInterests":"","formattedTitle":"A hierarchical QP optimization control strategy for quadruped robots facing a variety of structural terrains","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Quadruped robot, Gait scheduling based on CPG, Terrain estimation, Footfall planning, Hierarchical QP optimization control, Impedance control","lastPublishedDoi":"10.21203/rs.3.rs-6704764/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6704764/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAddressing the dynamic stability issue of quadruped robots with a relatively high proportion of leg mass in various structured terrains, this paper proposes a hybrid control strategy. 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