Checkpoint 7

This commit is contained in:
Johnny Fernandes
2026-05-11 12:21:51 +01:00
parent fce0e0c786
commit a01a5c9cef
34 changed files with 1266 additions and 1038 deletions
+17 -9
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@@ -6,7 +6,7 @@ Two stages, strictly sequential:
sim demos (Strömbom on tracker output, K=4 frame stack)
bc_pretrain.py ──► runs/bc (Strömbom-imitated MLP)
bc/pretrain.py ──► runs/bc (Strömbom-imitated MLP)
▼ KL-regularised PPO fine-tune
@@ -17,10 +17,13 @@ runs/rl (deployed `rl` mode — beats BC and Strömbom)
```
herding_env.py — Gymnasium env (LiDAR raycast + tracker by default)
bc_pretrain.py — MSE + cosine BC of (obs, action) demos into MlpPolicy
train_ppo.py — KL-regularised PPO fine-tune of a BC checkpoint
bc/pretrain.py — MSE + cosine BC of (obs, action) demos into MlpPolicy
rl/train.py — KL-regularised PPO fine-tune of a BC checkpoint
eval.py — multi-seed analytic / learned policy comparison
runs/ — checkpoints (whitelisted entries in top-level .gitignore)
(Unit + integration tests live in the top-level ``tests/`` directory;
run with ``python -m pytest tests/``.)
```
## Setup
@@ -35,18 +38,23 @@ rollout collection, not gradient compute.
## End-to-end pipeline
The simplest way to run everything is the Makefile at the project
root: ``make`` does the full chain, ``make rl`` rebuilds whatever's
needed up to that point, etc. The individual stages below are kept
explicit for cases where you want to tune a single step.
```bash
# 1. Sim demos with the active-scan + Strömbom teacher under LiDAR
# perception. K=4 frame stack so the MLP has temporal context.
python -m tools.collect_demos --teacher strombom \
--out training/demos.npz --seeds-per-n 15 --subsample 3 --frame-stack 4
python -m training.bc.collect --teacher strombom \
--out training/bc/demos.npz --seeds-per-n 15 --subsample 3 --frame-stack 4
# 2. Behaviour-clone.
python -m training.bc_pretrain --demos training/demos.npz \
python -m training.bc.pretrain --demos training/bc/demos.npz \
--out training/runs/bc --epochs 60 --net-arch 512,512
# 3. KL-regularised PPO fine-tune of bc.
python -m training.train_ppo \
python -m training.rl.train \
--bc training/runs/bc --out training/runs/rl \
--total-timesteps 1000000
@@ -55,11 +63,11 @@ python -m training.eval --policy training/runs/rl \
--max-flock 10 --max-steps 15000 --n-seeds 10
```
`bc_pretrain.py` saves the **best-val_cos** snapshot, not the final
`bc/pretrain.py` saves the **best-val_cos** snapshot, not the final
epoch — multi-modal teachers make training noisy and the last epoch is
often worse than an earlier one.
`train_ppo.py` loads BC weights into both a trainable policy and a
`rl/train.py` loads BC weights into both a trainable policy and a
frozen reference, fixes `log_std` small, and adds `β · KL(π‖π_ref)` to
the loss so the policy can only move within a trust region around BC.
See the file header for hyperparameter rationale.