Coco-LIC
Coco-LIC 以非均勻 B 樣條(non-uniform B-spline)表示連續時間軌跡,依 IMU 感知的運動劇烈程度動態配置控制點,在平緩運動時使用較少控制點、劇烈運動時加密,以兼顧精度與計算量。視覺像素的深度直接取自全域光達地圖,建立幀對地圖重投影因子,避免在長滑動視窗中最佳化視覺深度。連續時間表示讓不同頻率、非同步的光達、IMU 與相機量測可在任意時刻查詢位姿後融合。
本頁內容
A continuous-time LIC odometry that adapts B-spline control-point density to motion and uses LiDAR map depth for frame-to-map visual factors, fusing asynchronous measurements without interpolation.
技術屬性
欄位內容為文獻擷取紀錄的原文用語(英文),以原文為據;「未查證」表示本研究尚未讀到該資訊,不代表該方法不具備此能力。
| 感測輸入 | 3D LiDAR (Velodyne VLP-16, HDL-32E, Livox Avia across datasets)、IMU、monocular camera |
|---|---|
| 原文測試平台 | vehicle (UrbanNav, human-driven)、sensor rig in a motion-capture area (carrying mode not stated)、R3LIVE and FAST-LIVO dataset rig (carrying mode not stated in this paper) |
| 狀態估計 | Factor-graph nonlinear least squares over the new control points and IMU biases of each 0.1 s interval (LiDAR point-to-plane, visual reprojection with Cauchy kernel, raw IMU and bias random-walk factors, marginalization prior), solved with Levenberg-Marquardt in Ceres; separate cubic non-uniform B-splines for rotation and translation; raw IMU used without preintegration |
| 資料關聯 | LiDAR planar (surf) points matched to 5 nearest neighbours of the local keyscan map for point-to-plane residuals; global-map LiDAR points tracked across images by KLT optical flow, outliers removed with fundamental-matrix RANSAC and PnP, then used in frame-to-map reprojection factors without visual depth optimization |
| 時間表示 | continuous-time (non-uniform B-spline with control-point density adapted to IMU-sensed motion) |
| 去畸變 | No separate deskew step: each LiDAR planar point is transformed with the spline pose queried at its own timestamp, so motion distortion removal and trajectory estimation happen simultaneously |
| 迴圈閉合 | none reported |
| 全域最佳化 | none |
| 地圖表示 | Two LiDAR maps: a local map built from keyscans selected by time and space for scan-to-map point-to-plane matching, and a global LiDAR map stored in 0.1 m voxels whose points are projected into images for frame-to-map visual factors; marginalization acts on control points, not on the map |
| 先驗資訊 | LiDAR-IMU and camera-IMU extrinsics pre-calibrated; IMU noise parameters from datasheets; system assumed stationary at start to initialize IMU bias and gravity |
| 可輸出幾何 | 原文未報告 (evaluation is trajectory-based) |
| 計算需求 | Desktop Intel i7-8700 @ 3.2 GHz with 32 GB RAM; on UrbanNav Medium the average module times are 31.46 ms LiDAR association, 18.90 ms visual association and 9.09 ms optimization, and the 785 s sequence is processed in about 639 s |
使用設備
原文使用的感測器、運算硬體與載具(equipment)。型號保留原文寫法,連結到設備頁中同一型號的歸併名稱;角色依原文用途分為方法輸入、資料集感測器、執行運算平台、參考或真值量測(reference or ground truth)與比較對象設備。
| 類別 | 型號(原文寫法) | 角色 | 資料集 | 原文規格 | 出處 |
|---|---|---|---|---|---|
| LiDAR | Velodyne VLP-16 | 方法輸入 | self-collected mocap sequences (Smooth, Violent, Hybrid) | 16-beam 3D LiDAR, 10 Hz | (Lang et al., 2023, Sec. IV-A) |
| LiDAR | Livox Avia | 資料集感測器 | R3LIVE and FAST-LIVO challenging sequences | 10 Hz, solid-state small FoV | (Lang et al., 2023, Sec. IV-B1) |
| LiDAR | Velodyne HDL-32E | 資料集感測器 | UrbanNav | 32-beam 3D LiDAR, 10 Hz | (Lang et al., 2023, Sec. IV-B2) |
| 慣性量測單元(IMU) | Xsens MTi-300 | 方法輸入 | self-collected mocap sequences (Smooth, Violent, Hybrid) | 400 Hz | (Lang et al., 2023, Sec. IV-A) |
| 慣性量測單元(IMU) | Livox Avia internal IMU | 資料集感測器 | R3LIVE and FAST-LIVO challenging sequences | 200 Hz | (Lang et al., 2023, Sec. IV-B1) |
| 慣性量測單元(IMU) | Xsens MTi-10 | 資料集感測器 | UrbanNav | 400 Hz | (Lang et al., 2023, Sec. IV-B2) |
| 相機 | camera (model not stated) | 資料集感測器 | R3LIVE and FAST-LIVO challenging sequences | 15 Hz | (Lang et al., 2023, Sec. IV-B1) |
| 雙目相機 | stereo camera (model not stated) | 資料集感測器 | UrbanNav | 15 Hz; only the left camera used | (Lang et al., 2023, Sec. IV-B2) |
| 載具平台 | human-driving vehicle | 資料集感測器 | UrbanNav | urban data collection vehicle | (Lang et al., 2023, Sec. IV-B2) |
| 運算硬體 | desktop PC with Intel i7-8700 CPU | 執行運算平台 | 未標示 | 3.2 GHz, 32 GB RAM | (Lang et al., 2023, Sec. IV) |
| 其他 | motion capture system | 參考或真值量測 | self-collected mocap sequences (Smooth, Violent, Hybrid) | ground truth at 120 Hz, millimeter-level accuracy | (Lang et al., 2023, Sec. IV-A) |
作者報告的優勢與限制
優勢
- Non-uniform control points gave better accuracy-time trade-offs than uniform splines on violent and hybrid motion sequences with mocap ground truth; this experiment used LiDAR-inertial data only (cameras excluded), so it validates the spline placement rather than the full LIC system (Sec. IV-A, Table II)
- Plausible start-to-end drift on all degenerate R3LIVE and FAST-LIVO sequences tested (Sec. IV-B)
限制
- Map management efficiency left for future work (Sec. V)
- Evaluation is trajectory-only; no mapping-quality metric (inference from Sec. IV)
營建工程相關證據
原文未報告(資料為動作捕捉實驗、R3LIVE、FAST-LIVO 手持退化序列與 UrbanNav 都市車載資料)
原文驗證環境:公開基準、受控實驗
報告的性能數據
以下是原文作者報告的性能數值(author-reported results),不是本研究重新量測的結果。每張圖只並列同一個比較組(comparison group,同一張表、同一組實驗設定)內的方法;不同比較組之間的數值不可直接比較,也不構成排名。
本方法共出現在 6 個比較組,合計 41 筆紀錄。以下列出本方法紀錄最多的 4 組,其餘 2 組列在最後,並連到性能比較頁。
Chen et al., 2025b · Table 5 本方法 15 筆
指標ATE (m)
表格設定(擷取紀錄原文):ATE (m) per sequence, average of five runs, parameters not tuned per sequence; X = breakdown or error > 100 m; - = algorithm not adapted to this data. Only Metro tunnels and Stairs blocks extracted; shield-tunnel sequences are absent from Table 5 because all methods failed (Sec. 5.2). Stairs GT from PALoc (inlier RMSE 0.07 m alpha, 0.08 m beta); gamma stairs GT not accurate. (Chen et al., 2025b, Table 5)
ATE (m),GEODE · Metro tunnels, alpha (Velodyne VLP-16), Tunneling 3
只並列這張表在相同設定下報告的方法;以「本方法:」開頭者為本頁方法。失敗、未執行與未報告以標記呈現,不是 0。
- 不適用
- 失敗
按 Tab 進入圖表後,用上下方向鍵逐一瀏覽各類別,Esc 關閉提示框;也可開啟表格檢視閱讀全部數值。
這些是 Chen et al., 2025b 在此表設定下報告的數值(author-reported results),只能在同一個比較組內對照,不代表方法在其他資料或設定下的表現。
資料來源作者報告值(Chen et al., 2025b, Table 5)
| 方法(原文寫法) | 報告值 | 出處 |
|---|---|---|
| COIN-LIO | 無數值不適用註記(擷取紀錄):不適用 | (Chen et al., 2025b, Table 5 (VoR)) |
| FAST-LIO2 | 0.21 m | (Chen et al., 2025b, Table 5 (VoR)) |
| DLIO | 0.18 m | (Chen et al., 2025b, Table 5 (VoR)) |
| FAST-LIVO | 0.2 m | (Chen et al., 2025b, Table 5 (VoR)) |
| Coco-LIC本方法 | 無數值不適用註記(擷取紀錄):不適用 | (Chen et al., 2025b, Table 5 (VoR)) |
| R3LIVE | 0.59 m | (Chen et al., 2025b, Table 5 (VoR)) |
| LVI-SAM | 無數值失敗註記(擷取紀錄):failed | (Chen et al., 2025b, Table 5 (VoR)) |
| VINS-Fusion | 47.66 m | (Chen et al., 2025b, Table 5 (VoR)) |
Lang et al., 2023 · Table III 本方法 10 筆
表格設定(擷取紀錄原文):Start-to-end drift (translation m / rotation deg) on degenerate Livox Avia sequences without ground truth; rig returns to start; loop closure disabled; average of 6 runs; fail = drift over 10 m; L = LiDAR faces ground or walls, V1 = camera faces white wall, V2 = motion blur (Lang et al., 2023, Table III)
start-to-end drift error (translation),R3LIVE dataset · degenerate seq 00
只並列這張表在相同設定下報告的方法;以「本方法:」開頭者為本頁方法。失敗、未執行與未報告以標記呈現,不是 0。
按 Tab 進入圖表後,用上下方向鍵逐一瀏覽各類別,Esc 關閉提示框;也可開啟表格檢視閱讀全部數值。
這些是 Lang et al., 2023 在此表設定下報告的數值(author-reported results),只能在同一個比較組內對照,不代表方法在其他資料或設定下的表現。
資料來源作者報告值(Lang et al., 2023, Table III)
| 方法(原文寫法) | 報告值 | 出處 |
|---|---|---|
| FAST-LIO2 | 9.019 m | (Lang et al., 2023, Table III) |
| VINS-Mono | 0.807 m | (Lang et al., 2023, Table III) |
| R3LIVE | 0.035 m | (Lang et al., 2023, Table III) |
| FAST-LIVO | 0.42 m | (Lang et al., 2023, Table III) |
| CLIC | 0.031 m | (Lang et al., 2023, Table III) |
| Coco-LIC本方法原文提出 | 0.016 m | (Lang et al., 2023, Table III) |
Lang et al., 2023 · Table II 本方法 9 筆
指標RMSE of APE
表格設定(擷取紀錄原文):LiDAR-inertial only (cameras excluded) comparison of uniform B-splines with x control points per 0.1 s (uni-x) against the adaptive non-uniform placement; VLP-16 + Xsens MTi-300 rig with mocap ground truth; values averaged over 6 runs; optimization-time half of each cell omitted to respect the row cap (Lang et al., 2023, Table II)
RMSE of APE,self-collected mocap sequences · Smooth1
只並列這張表在相同設定下報告的方法;以「本方法:」開頭者為本頁方法。失敗、未執行與未報告以標記呈現,不是 0。
按 Tab 進入圖表後,用上下方向鍵逐一瀏覽各類別,Esc 關閉提示框;也可開啟表格檢視閱讀全部數值。
這些是 Lang et al., 2023 在此表設定下報告的數值(author-reported results),只能在同一個比較組內對照,不代表方法在其他資料或設定下的表現。
資料來源作者報告值(Lang et al., 2023, Table II)
| 方法(原文寫法) | 報告值 | 出處 |
|---|---|---|
| uni-1 (LIO, uniform B-spline) | 0.011 m | (Lang et al., 2023, Table II) |
| uni-2 (LIO, uniform B-spline) | 0.012 m | (Lang et al., 2023, Table II) |
| uni-3 (LIO, uniform B-spline) | 0.012 m | (Lang et al., 2023, Table II) |
| uni-4 (LIO, uniform B-spline) | 0.012 m | (Lang et al., 2023, Table II) |
| uni-5 (LIO, uniform B-spline) | 0.012 m | (Lang et al., 2023, Table II) |
| uni-8 (LIO, uniform B-spline) | 0.013 m | (Lang et al., 2023, Table II) |
| uni-16 (LIO, uniform B-spline) | 0.049 m | (Lang et al., 2023, Table II) |
| non-uni (LIO, adaptive non-uniform B-spline)本方法原文提出 | 0.011 m | (Lang et al., 2023, Table II) |
Lang et al., 2023 · Table IV 本方法 3 筆
指標RMSE of APE
表格設定(擷取紀錄原文):RMSE of APE on UrbanNav (HDL-32E, left camera of stereo pair, Xsens MTi-10, human-driven vehicle); R3LIVE not run because it supports only solid-state LiDAR; loop closure disabled; average of 6 runs (Lang et al., 2023, Table IV)
RMSE of APE,UrbanNav · UrbanNav-HK-Medium-Urban-1
只並列這張表在相同設定下報告的方法;以「本方法:」開頭者為本頁方法。失敗、未執行與未報告以標記呈現,不是 0。
按 Tab 進入圖表後,用上下方向鍵逐一瀏覽各類別,Esc 關閉提示框;也可開啟表格檢視閱讀全部數值。
這些是 Lang et al., 2023 在此表設定下報告的數值(author-reported results),只能在同一個比較組內對照,不代表方法在其他資料或設定下的表現。
資料來源作者報告值(Lang et al., 2023, Table IV)
| 方法(原文寫法) | 報告值 | 出處 |
|---|---|---|
| FAST-LIO2 | 6.734 m | (Lang et al., 2023, Table IV) |
| VINS-Mono | 102.582 m | (Lang et al., 2023, Table IV) |
| LVI-SAM | 7.456 m | (Lang et al., 2023, Table IV) |
| FAST-LIVO | 7.331 m | (Lang et al., 2023, Table IV) |
| CLIC | 6.923 m | (Lang et al., 2023, Table IV) |
| Coco-LIC本方法原文提出 | 6.031 m | (Lang et al., 2023, Table IV) |
其他比較組
來源
Lang et al., 2023
(2023)Coco-LIC: Continuous-Time Tightly-Coupled LiDAR-Inertial-Camera Odometry Using Non-Uniform B-SplineIEEE Robotics and Automation Letters, 8(11): 7074-7081
DOI 10.1109/lra.2023.3315542arXiv 2309.09808程式碼
同儕審查已出版已讀全文近十年查證後修正
相關版本
- 預印本:Coco-LIC arXiv (2023-09-18; RA-L accepted preprint) https://arxiv.org/abs/2309.09808
- 程式碼釋出:APRIL-ZJU/Coco-LIC https://github.com/APRIL-ZJU/Coco-LIC
程式碼:https://github.com/APRIL-ZJU/Coco-LIC(授權:GPL-3.0 (stated in README))。有公開程式碼不等於已被重現,也不代表目前版本與論文版本相同。