TaPD: Temporal-adaptive Progressive Distillation for Observation-Adaptive Trajectory Forecasting in Autonomous Driving
Authors: Mingyu Fan, Yi Liu, Hao Zhou, Deheng Qian, Mohammad Haziq Khan, Matthias Raetsch
Organizations: College of Information and Intelligent Science, Donghua University, Shanghai 201620 China. · School of Computing and Information Technology, Great Bay Institute for Advanced Study/Great Bay University, Dongguan, China, and also with the Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China. · Chongqing Chang’an Technology Co., Ltd, Chongqing 401120 China. · ViSiR, Reutlingen University, Alteburgstraße 150, 72762, Reutlingen, Germany.
Trajectory prediction is essential for autonomous driving, enabling vehicles to anticipate the motion of surrounding agents to support safe planning. However, most existing predictors assume fixed-length histories and suffer substantial performance degradation when observations are variable or extremely short in real-world settings (e.g., due to occlusion or a limited sensing range). We propose TaPD (Temporal-adaptive Progressive Distillation), a unified plug-and-play framework for observation-adaptive trajectory forecasting under variable history lengths. TaPD comprises two cooperative modules: an Observation-Adaptive Forecaster (OAF) for future prediction and a Temporal Backfilling Module (TBM) for explicit reconstruction of the past. OAF is built on progressive knowledge distillation (PKD), which transfers motion pattern knowledge from long-horizon "teachers" to short-horizon "students" via hierarchical feature regression, enabling short observations to recover richer motion context. We further introduce a cosine-annealed distillation weighting scheme to balance forecasting supervision and feature alignment, improving optimization stability and cross-length consistency. For extremely short histories where implicit alignment is insufficient, TBM backfills missing historical segments conditioned on scene evolution, producing context-rich trajectories that strengthen PKD and thereby improve OAF. We employ a decoupled pretrain-reconstruct-finetune protocol to preserve real-motion priors while adapting to backfilled inputs. Extensive experiments on Argoverse 1 and Argoverse 2 show that TaPD consistently outperforms strong baselines across all observation lengths, delivers especially large gains under very short inputs, and improves other predictors (e.g., HiVT) in a plug-and-play manner. Code will be available at https://github.com/zhouhao94/TaPD.
Figures & tables
Fig. 1 : The OAF pipeline with parameter sharing and progressive knowledge distillation.
Fig. 2 : The TBM temporal backfilling module for unobserved past trajectories backfilling.
Fig. 3 : The overview of TaPD training strategy.
Method
Argoverse 2 ( minADE6 / minFDE6 )
Argoverse 1 ( minADE6 / minFDE6 )
10Ts
20Ts
30Ts
40Ts
50Ts
5Ts
10Ts
15Ts
20Ts
DeMo_Ori
0.861/1.533
0.700/1.358
0.671/1.306
0.662/1.288
0.658/1.278
0.781/1.267
0.662/1.087
0.624/1.011
0.606/1.003
DeMo_IT
0.675/1.318
0.661/1.296
0.660/1.293
0.659/1.287
0.658/1.278
0.669/1.078
0.634/1.031
0.612/0.988
0.606/1.003
DeMo_DTO
0.672/1.307
0.658/1.291
0.650/1.279
0.647/1.268
0.645/1.265
0.662/1.064
0.628/1.025
0.605/0.991
0.599/1.010
DeMo_FLN
0.651/1.262
0.644/1.258
0.637/1.254
0.628/1.238
0.621/1.231
0.646/1.043
0.607/0.994
0.599/0.974
0.592/0.957
DeMo_LaKD
0.639 /1.262
0.627 /1.251
0.620 /1.243
0.617/1.236
0.617/1.232
0.631 /1.008
0.593/0.976
0.584/0.933
0.581/0.929
TABLE I : Variable-length trajectory prediction comparison on Argoverse 2 (left) and Argoverse 1 (right) validation sets. Best results are in bold and second best are underlined . Ts denotes the time steps of Tτ,a.k.a.,τΔT .
Method
minFDE6
minADE6
MR6
LGT [ 56 ]
1.93
1.02
0.30
SIMPL [ 57 ]
1.45
0.78
-
forecast-mae [ 32 ]
1.41
0.80
0.18
SeNeVA [ 58 ]
1.32
0.71
0.17
Realmotion [ 54 ]
1.31
0.66
0.15
QCNet [ 4 ]
1.27
0.73
0.16
TABLE II : Performance comparison on Argoverse 2 validation set . ”-” denotes that this result was not reported in their paper.
Method
minADE6
minFDE6
MR6
LTP [ 64 ]
0.78
1.07
-
LaneRCNN [ 17 ]
0.77
1.19
0.08
TPCN [ 65 ]
0.73
1.15
0.11
DenseTNT [ 27 ]
0.73
1.05
0.10
TNT [ 26 ]
0.73
1.29
0.09
mmTransformer [ 66 ]
0.71
1.15
0.11
TABLE III : Performance comparison on Argoverse 1 validation set . ”-” denotes that this result was not reported in their paper.
PS(OAF)
PKD(OAF)
TBM
minADE6 / minFDE6
10Ts
20Ts
30Ts
40Ts
50Ts
0.675/1.318
0.661/1.296
0.660/1.293
0.659/1.287
0.658/1.278
✓
0.650/1.289
0.637/1.256
0.629/1.238
0.624/1.226
0.616/1.211
✓
✓
0.621/1.216
0.610/1.200
0.608/1.196
0.604/1.185
0.601/1.172
✓
✓
✓
0.617/1.203
0.603/1.167
0.599/1.157
0.599/1.155
0.599/1.153
TABLE IV : Ablation study on the core components of TaPD on the Argoverse 2 validation set . PS denotes parameter-sharing mechanism.
Method
Combination
minADE6 / minFDE6
10Ts
20Ts
30Ts
40Ts
50Ts
DeMo_IT
-
0.675/1.318
0.661/1.296
0.660/1.293
0.659/1.287
0.658/1.278
DeMo_TaPD-3
30/40/50
0.671/1.313
0.627/1.224
0.609/1.201
0.608/1.195
0.605/1.174
DeMo_TaPD-4
20/30/40/50
0.651/1.274
0.606/1.188
0.605/1.182
0.605/1.178
0.603/1.162
DeMo_TaPD-5
10/20/30/40/50
0.617/1.203
0.603/1.167
0.599/1.157
0.599/1.155
0.599/1.153
TABLE V : Ablation study of different length combinations of observation lengths on the Argoverse 2 single-agent validation set .
Method
minADE6 / minFDE6
5Ts
10Ts
15Ts
20Ts
HiVT_Ori
0.943/1.540
0.768/1.201
0.732/1.124
0.702/1.070
HiVT_IT
0.781/1.224
0.738/1.121
0.711/1.083
0.702/1.070
HiVT_FLN
0.754/1.162
0.723/1.089
0.701/1.053
0.681/1.028
HiVT_TaPD(Ours)
0.704/1.083
0.662/1.012
0.674/1.003
0.660/0.964
TABLE VI : Performance Comparison of TaPD on HiVT on Argoverse 1 single-agent validation set .
Argoverse 2 ( minADE6 / minFDE6 )
Module
10Ts
20Ts
30Ts
40Ts
TBM
0.382/0.723
0.275/0.501
0.185/0.316
0.097/0.160
TABLE VII : Variable-length trajectory prediction performance of TBM on Argoverse 2 (upper) and Argoverse 1 (lower) validation sets.
Len
DeMo_IT
DeMo_TaPD
Params ↓
FLOPs ↓
Lat. ↓
Params ↓
FLOPs ↓
Lat. ↓
10Ts
3.431
0.678
23.370
6.831
1.213
88.568
20Ts
3.431
0.680
23.578
6.815
1.140
80.626
30Ts
3.431
0.683
23.878
6.800
1.066
84.238
40Ts
3.431
0.685
23.760
6.784
0.992
86.447
TABLE VIII : Parameters (M), FLOPs (G), and latency (ms) under different input lengths.
Fig. 4 : Qualitative comparison on the Argoverse 2 single-agent validation set under short observations (10 time steps). Each row corresponds to one scene, and the three columns show predictions from (a) DeMo_IT, (b) DeMo_OAF, and (c) our DeMo_TaPD, respectively, given the same input. The observed history is shown as a solid black segment. The ground-truth future trajectory is shown in solid red with an arrow. Green dashed arrows denote multiple predicted trajectories. For methods with backfilling, the reconstructed (unobserved) history is shown as a blue dashed segment, and the corresponding ground-truth unobserved history segment is shown in solid orange.
School of Mathematical Sciences, Shanghai Jiao Tong University, Shanghai 200240, China · Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai 200030, China · Shanghai Key Laboratory of Psychotic Disorders, and Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai 200030, China