{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:3LMHCC5S7AXE5NVND4S2O33SHW","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"148c02f4dc0548ba145140ffe9a9ab4cd9eb02e73b87162a6a012729cf34cdb3","cross_cats_sorted":["cs.SY","eess.SY"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.RO","submitted_at":"2021-03-21T13:34:17Z","title_canon_sha256":"39bf8cae1980ef42191be16f90c423ba9b9b984dcfce00dcc48629844a2b0e5f"},"schema_version":"1.0","source":{"id":"2103.11393","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2103.11393","created_at":"2026-07-05T02:24:59Z"},{"alias_kind":"arxiv_version","alias_value":"2103.11393v1","created_at":"2026-07-05T02:24:59Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2103.11393","created_at":"2026-07-05T02:24:59Z"},{"alias_kind":"pith_short_12","alias_value":"3LMHCC5S7AXE","created_at":"2026-07-05T02:24:59Z"},{"alias_kind":"pith_short_16","alias_value":"3LMHCC5S7AXE5NVN","created_at":"2026-07-05T02:24:59Z"},{"alias_kind":"pith_short_8","alias_value":"3LMHCC5S","created_at":"2026-07-05T02:24:59Z"}],"graph_snapshots":[{"event_id":"sha256:5c44fe9d1aa5c9634194a594ecd5db85fff1440854f48b7c88c769030f4c264b","target":"graph","created_at":"2026-07-05T02:24:59Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2103.11393/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Goal: This paper presents an algorithm for estimating pelvis, thigh, shank, and foot kinematics during walking using only two or three wearable inertial sensors. Methods: The algorithm makes novel use of a Lie-group-based extended Kalman filter. The algorithm iterates through the prediction (kinematic equation), measurement (pelvis position pseudo-measurements, zero-velocity update, and flat-floor assumption), and constraint update (hinged knee and ankle joints, constant leg lengths). Results: The inertial motion capture algorithm was extensively evaluated on two datasets showing its performan","authors_text":"Luke Wicent Sy, Nigel H. Lovell, Stephen J. Redmond","cross_cats":["cs.SY","eess.SY"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.RO","submitted_at":"2021-03-21T13:34:17Z","title":"Estimating Lower Body Kinematics using a Lie Group Constrained Extended Kalman Filter and Reduced IMU Count"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2103.11393","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:357881fe64b4e13b0e57c7a9655732977ed3e2a0afdd422d8dda7f6a5b7caf47","target":"record","created_at":"2026-07-05T02:24:59Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"148c02f4dc0548ba145140ffe9a9ab4cd9eb02e73b87162a6a012729cf34cdb3","cross_cats_sorted":["cs.SY","eess.SY"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.RO","submitted_at":"2021-03-21T13:34:17Z","title_canon_sha256":"39bf8cae1980ef42191be16f90c423ba9b9b984dcfce00dcc48629844a2b0e5f"},"schema_version":"1.0","source":{"id":"2103.11393","kind":"arxiv","version":1}},"canonical_sha256":"dad8710bb2f82e4eb6ad1f25a76f723d8f95e6744e5db642c8aa47c1e7adbdfa","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"dad8710bb2f82e4eb6ad1f25a76f723d8f95e6744e5db642c8aa47c1e7adbdfa","first_computed_at":"2026-07-05T02:24:59.923357Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T02:24:59.923357Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"0QRWYYqu55X79fPA0GfhoRYqq7/5lxsPA1OZJ1/Os8fS/m+LZ7uirgjhOkjxLrk/9Ml6M7KI52fhhIDBPxdOAA==","signature_status":"signed_v1","signed_at":"2026-07-05T02:24:59.923839Z","signed_message":"canonical_sha256_bytes"},"source_id":"2103.11393","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:357881fe64b4e13b0e57c7a9655732977ed3e2a0afdd422d8dda7f6a5b7caf47","sha256:5c44fe9d1aa5c9634194a594ecd5db85fff1440854f48b7c88c769030f4c264b"],"state_sha256":"289b7ad5a199225488d0f522fec0e4d0394ac61183bff431e41a3e00e0232a6b"}