lerobot/examples/4_train_policy.py

68 lines
2.4 KiB
Python

"""This scripts demonstrates how to train Diffusion Policy on the PushT environment.
Once you have trained a model with this script, you can try to evaluate it on
examples/2_evaluate_pretrained_policy.py
"""
import os
from pathlib import Path
import torch
from omegaconf import OmegaConf
from lerobot.common.datasets.factory import make_dataset
from lerobot.common.policies.diffusion.configuration_diffusion import DiffusionConfig
from lerobot.common.policies.diffusion.modeling_diffusion import DiffusionPolicy
from lerobot.common.utils.utils import init_hydra_config
output_directory = Path("outputs/train/example_pusht_diffusion")
os.makedirs(output_directory, exist_ok=True)
# Number of offline training steps (we'll only do offline training for this example.
# Adjust as you prefer. 5000 steps are needed to get something worth evaluating.
training_steps = 5000
device = torch.device("cuda")
log_freq = 250
# Set up the dataset.
hydra_cfg = init_hydra_config("lerobot/configs/default.yaml", overrides=["env=pusht"])
dataset = make_dataset(hydra_cfg)
# Set up the the policy.
# Policies are initialized with a configuration class, in this case `DiffusionConfig`.
# For this example, no arguments need to be passed because the defaults are set up for PushT.
# If you're doing something different, you will likely need to change at least some of the defaults.
cfg = DiffusionConfig()
# TODO(alexander-soare): Remove LR scheduler from the policy.
policy = DiffusionPolicy(cfg, lr_scheduler_num_training_steps=training_steps, dataset_stats=dataset.stats)
policy.train()
policy.to(device)
# Create dataloader for offline training.
dataloader = torch.utils.data.DataLoader(
dataset,
num_workers=4,
batch_size=cfg.batch_size,
shuffle=True,
pin_memory=device != torch.device("cpu"),
drop_last=True,
)
# Run training loop.
step = 0
done = False
while not done:
for batch in dataloader:
batch = {k: v.to(device, non_blocking=True) for k, v in batch.items()}
info = policy.update(batch)
if step % log_freq == 0:
print(f"step: {step} loss: {info['loss']:.3f} update_time: {info['update_s']:.3f} (seconds)")
step += 1
if step >= training_steps:
done = True
break
# Save the policy and configuration for later use.
policy.save(output_directory / "model.pt")
OmegaConf.save(hydra_cfg, output_directory / "config.yaml")