{"id":"090144b9-95b0-4c62-8766-4edb420d6def","companyId":"15427f6f-23a1-436f-af33-9fb637a959ba","modelName":"MARBLE","slug":"duke-marble","description":"MARBLE (Duke General Robotics Lab; Weaver, Xia, Lo, Huang, Chen; arXiv 2609.27358) is a fully enclosed omnidirectional amphibious rolling robot. Three orthogonal internal mass sliders shift 700 g masses over 220 mm strokes inside a sealed ~387 mm spherical shell with passive fins, producing land rolling and water-surface propulsion without external moving parts or mechanical reconfiguration. Research platform with planned open-source hardware/software; not a commercial product. Distinct from World Labs' Marble world-model brain and unrelated Marble delivery robots.","formFactor":"other","industryVertical":null,"environment":null,"maturityStage":"research","lifecycleState":"active","supersededByModelId":null,"specs":{},"manufacturerSerial":null,"reviewStatus":"reviewed","sources":[{"url":"https://arxiv.org/abs/2609.27358","title":"Omnidirectional Amphibious Locomotion via Internal Mass Actuation (arXiv:2609.27358)","sourceName":"arXiv","publishedAt":"2026-09-30"},{"url":"https://arxiv.org/html/2609.27358","title":"MARBLE HTML paper (arXiv:2609.27358)","sourceName":"arXiv","publishedAt":"2026-09-30"},{"url":"https://generalroboticslab.com/MARBLE","title":"MARBLE project page (Duke General Robotics Lab)","sourceName":"Duke General Robotics Lab","publishedAt":"2026-09-30"},{"url":"https://x.com/lukas_m_ziegler/status/2105264331445186892","title":"Secondary demo clip of MARBLE sphere robot","sourceName":"X (@lukas_m_ziegler)","publishedAt":"2026-09-30"}],"aliases":["MARBLE","Duke MARBLE","Omnidirectional Amphibious Locomotion via Internal Mass Actuation"],"collisionRisk":"low","reviewNote":null,"manufacturerTermForTeleop":null,"keyFacts":[{"label":"Actuation (project-stated)","value":"Project-stated ([project-stated](https://arxiv.org/abs/2609.27358)): three mutually orthogonal linear sliders each shift a 700 g mass over a 220 mm stroke inside a sealed spherical shell (~387 mm outer diameter) so the same internal mass actuation produces land rolling and water-surface propulsion via passive fins, with no external moving parts and no mechanical reconfiguration between media. Cap: paper-reported hardware"},{"label":"Locomotion results (project-stated)","value":"Project-stated ([project-stated](https://arxiv.org/abs/2609.27358)): authors report terrestrial runs reaching mean ~0.75 m/s (max ~1.03 m/s), aquatic mean ~0.38 m/s, plus demonstrated land-water transitions and continued locomotion during direct shell contact with obstacles. Cap: author-reported lab results"},{"label":"MARBLE page prints 1.2 kg shell and 8 mm fins","value":"Duke General Robotics Lab's MARBLE page prints shell mass 1.2 kg and fin height 8 mm in the robot specifications table. The stored 387 mm diameter and 700 g slider sentence is not this shell-mass cell ([MARBLE](https://generalroboticslab.com/MARBLE))."},{"label":"MARBLE page prints 100 Hz and 4S 16 V","value":"The same specifications table prints position control at 100 Hz, CubeMars GL40 II motors, and a 4S LiPo battery at 16 V. Those cells are not the stored terrestrial and aquatic speed sentence ([MARBLE](https://generalroboticslab.com/MARBLE))."}],"createdAt":"2026-09-30T15:56:21.586Z","updatedAt":"2026-10-04T01:55:13.091Z","unitsInFieldClaimed":null,"unitsInFieldVerified":null,"unitsManufacturedClaimed":null,"unitsManufacturedVerified":null,"unitsAsOf":null,"unitsSource":null,"salesModel":null,"priceUndisclosedSince":null,"autonomyClass":null,"autonomyStatement":null,"autonomyStatementSource":null,"demoForensics":null,"exportControlClass":null,"minCommitment":null,"warrantyTerms":null,"serviceModel":null,"productionRateClaimed":null,"productionRateEvidenced":null,"teleopRatioDisclosed":null,"interventionRateDisclosed":null,"jsonLd":{"@context":"https://schema.org","@type":"Product","@id":"https://registry.deploy.report/models/duke-marble","url":"https://registry.deploy.report/models/duke-marble","name":"MARBLE","alternateName":["MARBLE","Duke MARBLE","Omnidirectional Amphibious Locomotion via Internal Mass Actuation"],"description":"MARBLE (Duke General Robotics Lab; Weaver, Xia, Lo, Huang, Chen; arXiv 2609.27358) is a fully enclosed omnidirectional amphibious rolling robot. Three orthogonal internal mass sliders shift 700 g masses over 220 mm strokes inside a sealed ~387 mm spherical shell with passive fins, producing land rolling and water-surface propulsion without external moving parts or mechanical reconfiguration. Research platform with planned open-source hardware/software; not a commercial product. Distinct from World Labs' Marble world-model brain and unrelated Marble delivery robots.","identifier":"090144b9-95b0-4c62-8766-4edb420d6def","category":"other","publisher":{"@id":"https://deploy.report/#organization"}},"framework_metadata":{"framework_schema_version":"0.1.0","verification_status":"verified","maturity_stage":"research","lifecycle_state":"active","architectural_position":{"cohort":"other","sub_cohorts":[]},"within_cohort_verified_vs_claimed_pair":null,"cap_flags":[],"verification_depth":{"sources_count":4,"primary_source_types":["preprint"]}}}