EgoRefine: Ego-Referenced Predictive Alignment and Trajectory-Conditioned Reliability-Aware Fusion for Asynchronous Collaborative Perception
Authors: Lingzhao Kong, Yongsheng Zang, Yu Kang, Kailun Yang, Jie Fu, Yukun Zuo, Zhiyong Li
Organizations: School of Computer Science and Electronic Engineering, Hunan University, Changsha 410082, China · School of Artificial Intelligence and Robotics, Hunan University, Changsha 410012, China · National Engineering Research Center of Robot Visual Perception and Control Technology, Hunan University, Changsha 410082, China · Nanjing University of Posts and Telecommunications, Nanjing 210003, China
Collaborative perception enables connected agents to share complementary observations for 3D object detection, extending sensing range and mitigating occlusion. Under asynchronous communication, however, cooperative features arrive with temporal delay. Existing prediction-based methods compensate for these features mainly from the transmitting agent's own history, leaving residual misalignment with the ego agent's current observation; subsequent fusion also often overlooks spatial variations in alignment quality. We propose EgoRefine, an ego-referenced predictive alignment and reliability-aware fusion framework for asynchronous collaborative perception. Its Ego-referenced Predictive Alignment module uses the current ego feature to guide cooperative trajectory-field prediction and refines the sampling offsets along an ego-referenced trajectory direction. Its Trajectory-conditioned Reliability-aware Fusion module treats the trajectory discrepancy between the ego and cooperative streams and the directional refinement magnitude as alignment cues, using them to condition the relation between aligned features and adaptively reweight the two streams before convolutional fusion. Experiments on V2V4Real and DAIR-V2X-Seq show that EgoRefine outperforms TraF-Align by 1.6 and 2.9 points on average in [email protected] and [email protected], respectively. The source code will be made publicly available at https://github.com/godk0509/EgoRefine.
Figures & tables
Fig. 1: Motivation of EgoRefine. (a) Communication latency causes spatiotemporal misalignment between the delayed CAV observation and the current ego observation. (b) Typical prediction-based methods compensate for the delayed CAV feature from its own history and directly fuse it with the current ego feature. (c) EgoRefine uses the current ego feature to guide delayed-feature prediction and reweights the aligned ego and CAV features using alignment cues before fusion.
Fig. 2: Overview of EgoRefine for asynchronous collaborative 3D object detection. EPA uses the current ego stream as a reference to guide delayed CAV features at both the feature and trajectory-offset levels, producing aligned ego and CAV representations. TRF further conditions the ego-CAV feature relation on ego-CAV trajectory discrepancy and directional refinement magnitude to estimate reliability-aware fusion weights before fusion and 3D detection.
Method
V2V4Real
DAIR-V2X-Seq
0 ms
100 ms
200 ms
300 ms
400 ms
0 ms
100 ms
200 ms
300 ms
400 ms
Single Agent
48.75/30.53
48.75/30.53
48.75/30.53
48.75/30.53
48.75/30.53
51.31/40.45
51.31/40.45
51.31/40.45
51.31/40.45
51.31/40.45
AttFuse [ 30 ]
63.84/33.30
59.16/27.36
55.57/26.03
53.25/25.44
51.69/25.09
68.94/49.68
65.83/45.76
63.02/44.24
61.61/43.28
60.19/42.53
F-Cooper [ 31 ]
66.86/33.39
62.15/27.61
58.03/26.30
55.31/25.46
53.92/24.95
69.47/50.01
65.85/44.96
62.74/43.21
61.12/42.28
60.01/41.70
V2VNet [ 20 ]
67.11/35.47
61.97/29.14
58.09/27.85
56.26/27.43
54.62/26.75
71.44/51.91
67.26/46.63
63.84/44.59
61.68/43.24
59.78/42.08
Where2comm [ 23 ]
67.03/37.55
61.86/31.52
58.22/30.20
56.22/29.71
54.47/29.07
68.37/48.50
64.81/44.32
61.51/42.80
59.66/41.63
58.25/40.80
TABLE I: Performance comparison of the vehicle class on the V2V4Real and DAIR-V2X-Seq validation sets under different communication latencies ([email protected]/0.7, %). Results of compared methods are taken from TraF-Align [ 11 ] . Best in bold, second best underlined.
EPA
TRF
Time Latency
0 ms
100 ms
200 ms
300 ms
400 ms
76.90/58.31
73.95/53.68
72.69/52.83
71.66/52.33
71.22/52.01
✓
78.30/60.31
75.32/55.48
74.18/54.79
73.30/54.17
72.21/53.43
✓
✓
78.49/61.31
75.46/56.16
74.26/55.21
73.38/54.53
72.73/54.42
TABLE II: Ablation study of EPA and TRF on DAIR-V2X-Seq under different communication latencies ([email protected]/0.7, %). The first row is the TraF-Align baseline.
Fig. 3: Ablation study of the two components in EPA on DAIR-V2X-Seq under different communication latencies. FG and TDR denote Feature-level Guidance and Trajectory-Directional Refinement, respectively.
Fig. 4: Qualitative comparison of CoBEVT, ERMVP, TraF-Align, and EgoRefine under different communication latencies. Green boxes denote ground-truth 3D bounding boxes and red boxes denote predicted results. The purple ellipses highlight representative regions where our method achieves more accurate localization and better robustness to temporal misalignment. In particular, EgoRefine preserves more stable detection quality as latency increases from 0 ms to 400 ms, while the competing methods exhibit more severe localization errors, missed detections, or inconsistent predictions.
Fig. 5: Hyperparameter sensitivity of the trajectory-directional refinement strength αd and feature-guidance strength αt on DAIR-V2X-Seq. [email protected] is averaged over the asynchronous latency settings from 100 to 400 ms, with all components of EgoRefine enabled.
Collaborative perception extends the sensing range of autonomous vehicles, but its performance degrades when shared features arrive stale or incomplete. Most latency-robust methods compensate delayed collaborator features through flow-guided alignment or direct feature transport. In this work, we formulate asynchronous collaborative perception as temporal residual prediction. Our Temporal Residual Bottleneck keeps a deterministic pose-warped collaborator feature as a conservative anchor and uses a Δt-conditioned xLSTM to extract residual temporal evidence from the available history. A detector-facing residual bottleneck then applies only gated, regularized corrections before ego-side fusion, reducing the risk of overwriting reliable static structure when temporal correspondence is uncertain. Experiments on DAIR-V2X and OPV2V show that our method is especially effective under severe fixed/irregular delays and packet drops. On DAIR-V2X, the reported checkpoint trades a small amount of synchronized peak accuracy for better robustness under stronger communication degradation. Controlled diagnostics further indicate that direct feature transport has oracle headroom but can become unreliable when deployed without accurate correspondence. These results support temporal residual fusion as a practical alternative for asynchronous and incomplete collaborative perception. Code will be publicly released at https://url.fzi.de/8dk38.
Melih Yazgan, Ahmed Abouelazm, J. Marius Zöllner
FZI Research Center for Information Technology · Karlsruhe Institute of Technology
Collaborative perception extends the sensing range of a single vehicle by fusing observations from nearby agents, which improves the robustness of autonomous driving. In realistic deployments, however, the received collaborator messages are often affected by both communication delay and relative-pose noise, which jointly cause stale observations, spatial misalignment, and unstable feature fusion. Existing methods usually address these issues from either the spatial or temporal side, but handling them jointly in a unified and efficient manner remains challenging. In this paper, we propose CoAnchor, an anchor-centric spatio-temporal alignment framework for asynchronous collaborative perception. Instead of directly reasoning on dense BEV features, CoAnchor builds sparse object-level spatio-temporal anchors as a shared interface for pose correction and tightly connects spatial refinement, temporal propagation, and current-time verification within one unified loop, while keeping the overall correction process lightweight. Extensive experiments on both simulated and real-world datasets illustrate that CoAnchor remains competitive under clean settings and improves the robustness under joint delay and pose perturbations with a favorable practical accuracy-efficiency trade-off.
Chi Li, Rui Lin, Aobo Ji +1
State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing, China
Predicting future trajectories of surrounding traffic agents is critical for safe autonomous navigation and collision avoidance. Despite all advances in the trajectory forecasting realm, the prediction models remains vulnerable to uncertainty caused by occlusions, limited sensing range, and perception errors. Collaborative vehicle-to-vehicle (V2V) approaches help reduce this uncertainty by sharing complementary information. Existing collaborative trajectory prediction methods typically fuse feature maps at the perception stage to construct a holistic scene view. Further this holistic representation is decoded into the future trajectories. Such design incurs substantial communication overhead due to the exchange of high-dimensional feature representations and often assumes idealized bandwidth and synchronization, limiting practical deployment. We address these limitations by shifting collaboration from perception to the prediction module and introducing a late-fusion framework for shared forecasts. The framework is model-agnostic and treats collaborating vehicles as independent asynchronous agents. We evaluate the approach on the OPV2V, V2V4Real, and DeepAccident datasets, comparing individual and collaborative forecasting. Across all datasets, late fusion consistently reduces miss rate and improves trajectory success rate (TSR0.5), defined as the fraction of ground-truth agents with final displacement error below 0.5 m. On the real-world V2V4Real dataset, collaborative prediction improves the success rate by 1.69% and 1.22% for both intelligent vehicles, respectively, compared with individual forecasting.
Nadya Abdel Madjid, Murad Mebrahtu, Zakhar Yagudin +5
Khalifa University, Computer Science, Abu Dhabi, UAE · Khalifa University, KUCARS-KU Center for Autonomous Robotic Systems, Department of Computer Science, Abu Dhabi, UAE · Khalifa University, Computer and Information Engineering, Abu Dhabi, UAE +2