Eni Solomon Laughter

2papers

2 Papers

35.2SYMay 12
Lane-Aware Graph Attention Network for Multi-Vehicle Trajectory Prediction in Expressway Merge Zones

Eni Solomon Laughter

Accurate multi-vehicle trajectory prediction in expressway merge and diverge areas is fundamental to the decision-making frameworks of autonomous vehicle systems. However, the majority of existing graph-based prediction models are developed and validated on mainline freeway segments and do not address the geometrically distinct interaction structures that characterize merge zones. Furthermore, standard evaluation protocols rely exclusively on displacement error metrics, leaving the safety consequences of predicted trajectories unquantified. This paper proposes a Lane-Aware Graph Attention Network (LA-GAT) that encodes vehicle interaction within dynamic scene graphs, augmented with a trainable lane-relationship attention bias that prioritizes merge-conflict interactions from the outset of training. The model is pre-trained on the raw NGSIM US-101 and I-80 datasets and subsequently fine-tuned on UAV-captured UTE SQM-W-1 trajectory data from a Chinese expressway merge area, with final evaluation on the held-out SQM-W-2 dataset. Evaluation spans both displacement metrics (ADE, FDE at 1s, 3s, 5s horizons) and surrogate safety measures (TTC violation rate, DRAC exceedance rate, collision rate). Fine-tuned results on SQM-W-2 yield ADE of 0.865 m at 1s and 2.518 m at 3s, demonstrating that drone-informed fine-tuning substantially reduces the cross-dataset transfer gap. The deliberate use of unfiltered NGSIM data is shown to characterize raw-condition generalization limits, with the performance degradation attributed to the well-documented measurement errors in that dataset.

37.0SYMay 6
Kinematic Discriminants of Deceleration Behavior Modes in Car-Following: Evidence from NGSIM Trajectory Data

Eni Solomon Laughter

Gap-closing rate and visual looming swap discriminative dominance depending on deceleration intensity - a finding that reconciles a long-standing conflict in the car-following literature and challenges spacing-centered assumptions in traditional driver behavior models. This study presents a two-stage analytical framework that distinguishes between information availability (kinematic variables measurable in the environment) and information utilization (variables that demonstrably separate driver behavioral patterns), applied to 1,060,119 valid car-following observations from the NGSIM trajectory dataset (2,932 vehicles). Six kinematic features are extracted, and deceleration events are detected under two threshold conditions (-0.5 m/s^2 and -0.3 m/s^2). K-means clustering identifies behavioral modes, and one-way ANOVA with eta-squared effect sizes ranks each feature's discriminative power. Three key findings emerge: (1) threshold selection fundamentally shapes behavioral inference - the stricter threshold yields three interpretable modes while the permissive threshold collapses these to two; (2) hard braking prioritizes gap-closing rate (eta^2 = 0.715) while moderate braking emphasizes visual looming (eta^2 = 0.574); and (3) spacing headway is negligible (eta^2 <= 0.014) across both thresholds. These findings provide empirically grounded candidates for perceptual cue prioritization and have direct implications for ADAS warning system design and autonomous vehicle control.