{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:RQTSAN3LTOARVHEW5LRIQEC5LZ","short_pith_number":"pith:RQTSAN3L","canonical_record":{"source":{"id":"1910.13174","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.RO","submitted_at":"2019-10-29T10:28:22Z","cross_cats_sorted":[],"title_canon_sha256":"078113062aa1268f1ad0fe3b031f0f02b0883d9c7423ac1b9c53562d44ae3155","abstract_canon_sha256":"050525646d47634b7f7b09f9714bbb85b6468071bef35e75ab54274330892068"},"schema_version":"1.0"},"canonical_sha256":"8c2720376b9b811a9c96eae288105d5e6ad8983446baf30b904b9b9961a64b5b","source":{"kind":"arxiv","id":"1910.13174","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1910.13174","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"arxiv_version","alias_value":"1910.13174v1","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1910.13174","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"pith_short_12","alias_value":"RQTSAN3LTOAR","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"pith_short_16","alias_value":"RQTSAN3LTOARVHEW","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"pith_short_8","alias_value":"RQTSAN3L","created_at":"2026-07-05T00:15:27Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:RQTSAN3LTOARVHEW5LRIQEC5LZ","target":"record","payload":{"canonical_record":{"source":{"id":"1910.13174","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.RO","submitted_at":"2019-10-29T10:28:22Z","cross_cats_sorted":[],"title_canon_sha256":"078113062aa1268f1ad0fe3b031f0f02b0883d9c7423ac1b9c53562d44ae3155","abstract_canon_sha256":"050525646d47634b7f7b09f9714bbb85b6468071bef35e75ab54274330892068"},"schema_version":"1.0"},"canonical_sha256":"8c2720376b9b811a9c96eae288105d5e6ad8983446baf30b904b9b9961a64b5b","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T00:15:27.557851Z","signature_b64":"48wp7nlXdSMjnRSzrp7/KRD1aGfHunHSx+FNQWeQrYLJM1/NPOGKxUI0PbJnO62O4ZxGbmVZkKiCK6qXBr0kBA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"8c2720376b9b811a9c96eae288105d5e6ad8983446baf30b904b9b9961a64b5b","last_reissued_at":"2026-07-05T00:15:27.557451Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T00:15:27.557451Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1910.13174","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T00:15:27Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"o33uPZ0v/adpcD6sR14uZtoRq6BykeiU2JH7moN1SJ6CtkQZZfyhQ6Ddstdki4z29+BPcc60Z7Ph6+UFi6sPAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-31T17:38:14.757413Z"},"content_sha256":"5c67e2162739f5b8189c4b1dbd702081ef5cb438183c480abff1b0b35ac6f44c","schema_version":"1.0","event_id":"sha256:5c67e2162739f5b8189c4b1dbd702081ef5cb438183c480abff1b0b35ac6f44c"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:RQTSAN3LTOARVHEW5LRIQEC5LZ","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Autonomous UAV Landing System Based on Visual Navigation","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.RO","authors_text":"Lei Qiao, Ming Liu, Min Sun, Peng Han, Rui Fan, Ruiwen Yao, Tielong Shen, Weidong Zhang, Yilong Zhu, Zhixin Wu","submitted_at":"2019-10-29T10:28:22Z","abstract_excerpt":"In this paper, we present an autonomous unmanned aerial vehicle (UAV) landing system based on visual navigation. We design the landmark as a topological pattern in order to enable the UAV to distinguish the landmark from the environment easily. In addition, a dynamic thresholding method is developed for image binarization to improve detection efficiency. The relative distance in the horizontal plane is calculated according to effective image information, and the relative height is obtained using a linear interpolation method. The landing experiments are performed on a static and a moving platf"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1910.13174","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/1910.13174/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T00:15:27Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"rs3btBVSr1UsXD96IkoCCStEhlOMXj8pGQqjX6AsZ03srFObVIq8rueGiRy4lKaK4obILoBvIvd1+2UB3n2RAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-31T17:38:14.757708Z"},"content_sha256":"a676ebce0932a134c892f3d0c3d2616242e2a86bb19d8a20da018ff5d73f8646","schema_version":"1.0","event_id":"sha256:a676ebce0932a134c892f3d0c3d2616242e2a86bb19d8a20da018ff5d73f8646"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/RQTSAN3LTOARVHEW5LRIQEC5LZ/bundle.json","state_url":"https://pith.science/pith/RQTSAN3LTOARVHEW5LRIQEC5LZ/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/RQTSAN3LTOARVHEW5LRIQEC5LZ/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-07-31T17:38:14Z","links":{"resolver":"https://pith.science/pith/RQTSAN3LTOARVHEW5LRIQEC5LZ","bundle":"https://pith.science/pith/RQTSAN3LTOARVHEW5LRIQEC5LZ/bundle.json","state":"https://pith.science/pith/RQTSAN3LTOARVHEW5LRIQEC5LZ/state.json","well_known_bundle":"https://pith.science/.well-known/pith/RQTSAN3LTOARVHEW5LRIQEC5LZ/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:RQTSAN3LTOARVHEW5LRIQEC5LZ","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":"050525646d47634b7f7b09f9714bbb85b6468071bef35e75ab54274330892068","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.RO","submitted_at":"2019-10-29T10:28:22Z","title_canon_sha256":"078113062aa1268f1ad0fe3b031f0f02b0883d9c7423ac1b9c53562d44ae3155"},"schema_version":"1.0","source":{"id":"1910.13174","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1910.13174","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"arxiv_version","alias_value":"1910.13174v1","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1910.13174","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"pith_short_12","alias_value":"RQTSAN3LTOAR","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"pith_short_16","alias_value":"RQTSAN3LTOARVHEW","created_at":"2026-07-05T00:15:27Z"},{"alias_kind":"pith_short_8","alias_value":"RQTSAN3L","created_at":"2026-07-05T00:15:27Z"}],"graph_snapshots":[{"event_id":"sha256:a676ebce0932a134c892f3d0c3d2616242e2a86bb19d8a20da018ff5d73f8646","target":"graph","created_at":"2026-07-05T00:15:27Z","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/1910.13174/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"In this paper, we present an autonomous unmanned aerial vehicle (UAV) landing system based on visual navigation. We design the landmark as a topological pattern in order to enable the UAV to distinguish the landmark from the environment easily. In addition, a dynamic thresholding method is developed for image binarization to improve detection efficiency. The relative distance in the horizontal plane is calculated according to effective image information, and the relative height is obtained using a linear interpolation method. The landing experiments are performed on a static and a moving platf","authors_text":"Lei Qiao, Ming Liu, Min Sun, Peng Han, Rui Fan, Ruiwen Yao, Tielong Shen, Weidong Zhang, Yilong Zhu, Zhixin Wu","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.RO","submitted_at":"2019-10-29T10:28:22Z","title":"Autonomous UAV Landing System Based on Visual Navigation"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1910.13174","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":"sha256:5c67e2162739f5b8189c4b1dbd702081ef5cb438183c480abff1b0b35ac6f44c","target":"record","created_at":"2026-07-05T00:15:27Z","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":"050525646d47634b7f7b09f9714bbb85b6468071bef35e75ab54274330892068","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.RO","submitted_at":"2019-10-29T10:28:22Z","title_canon_sha256":"078113062aa1268f1ad0fe3b031f0f02b0883d9c7423ac1b9c53562d44ae3155"},"schema_version":"1.0","source":{"id":"1910.13174","kind":"arxiv","version":1}},"canonical_sha256":"8c2720376b9b811a9c96eae288105d5e6ad8983446baf30b904b9b9961a64b5b","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"8c2720376b9b811a9c96eae288105d5e6ad8983446baf30b904b9b9961a64b5b","first_computed_at":"2026-07-05T00:15:27.557451Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T00:15:27.557451Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"48wp7nlXdSMjnRSzrp7/KRD1aGfHunHSx+FNQWeQrYLJM1/NPOGKxUI0PbJnO62O4ZxGbmVZkKiCK6qXBr0kBA==","signature_status":"signed_v1","signed_at":"2026-07-05T00:15:27.557851Z","signed_message":"canonical_sha256_bytes"},"source_id":"1910.13174","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5c67e2162739f5b8189c4b1dbd702081ef5cb438183c480abff1b0b35ac6f44c","sha256:a676ebce0932a134c892f3d0c3d2616242e2a86bb19d8a20da018ff5d73f8646"],"state_sha256":"7dca88a79c6c1efc25901cb374161eb955aab2780c83755cfd7d9983421f0af8"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"nOYvsG6pLSseTLvIHaeBwQbsiUszAL9cxvlA69EPondzT63Z/geQzUfnWH1cvEOBofVIa+mYSZqls2hkWdL4Bw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-31T17:38:14.760750Z","bundle_sha256":"2e251b0239057c756863118f8ec501b39aca76c36998ee71d3d3008215053846"}}