113 lines
3.4 KiB
Markdown
113 lines
3.4 KiB
Markdown
# CartPole Training Example
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CartPole is a classic control task in reinforcement learning. The goal is to keep the pole balanced by controlling the cart's left-right movement.
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## Task Description
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- **State Space**: Cart position, cart velocity, pole angle, pole angular velocity
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- **Action Space**: Apply force left or right
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- **Reward Function**: +1 reward for each step the pole stays upright
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- **Termination Conditions**: Pole angle exceeds ±15 degrees or episode length exceeds 10 seconds
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## Quick Start
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### 1. Environment Preview
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```bash
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uv run scripts/view.py --env cartpole
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```
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### 2. Start Training
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```bash
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# Train with default parameters
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uv run scripts/train.py --env cartpole
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# Customize number of environments
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uv run scripts/train.py --env cartpole --num-envs 1024
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# Enable rendering (visualize during training)
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uv run scripts/train.py --env cartpole --render
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```
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### 3. View Training Progress
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```bash
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uv run tensorboard --logdir runs/cartpole
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```
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### 4. Test Training Results
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```bash
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# Automatically find best policy for testing (recommended)
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uv run scripts/play.py --env cartpole
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# Manually specify policy file for testing
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uv run scripts/play.py --env cartpole --policy runs/cartpole/nn/best_policy.pickle
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```
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> **Tip**: The system will automatically find the latest and best policy files in the `runs/cartpole/` directory for testing. You can also manually specify specific policy files using the `--policy` parameter.
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## Configuration Parameters
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Main configuration parameters for the CartPole environment:
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```python
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@dataclass
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class CartPoleEnvCfg(EnvCfg):
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model_file: str = "path/to/inverted_pendulum.xml" # MJCF model file
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reset_noise_scale: float = 0.01 # Reset noise
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max_episode_seconds: float = 10.0 # Maximum episode length
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```
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Training configuration parameters:
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```python
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from dataclasses import dataclass
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from motrix_rl.skrl.cfg import PPOCfg
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from motrix_rl import registry
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@registry.rlcfg("cartpole")
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@dataclass
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class CartPolePPO(PPOCfg):
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max_env_steps: int = 10_000_000 # Maximum environment steps
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check_point_interval: int = 500 # Checkpoint interval
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# Network structure (small network suitable for simple tasks)
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policy_hidden_layer_sizes: tuple[int, ...] = (32, 32)
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value_hidden_layer_sizes: tuple[int, ...] = (32, 32)
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# PPO parameters
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rollouts: int = 32 # Experience replay rounds
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learning_epochs: int = 5 # Training rounds
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mini_batches: int = 4 # Number of mini-batches
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```
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**Note**: CartPole is a simple task and currently uses universal configuration. If you need to create specialized configurations for different training backends (JAX/Torch), refer to the environment configuration documentation examples.
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## Custom Training
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You can override default configurations through command line arguments:
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```bash
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uv run scripts/train.py --env cartpole \
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--num-envs 1024 \
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--train-backend jax \
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--sim-backend np
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```
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## Expected Results
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- Pole angle stays within ±5 degrees most of the time
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- Cart displacement range is reasonable
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## Troubleshooting
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If training performance is poor, you can try:
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1. Adjust learning rate (try 1e-4 to 1e-3)
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2. Increase number of environments (more parallel training)
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3. Adjust reward function weights
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4. Check if physical parameters are reasonable
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