pretrained config for act

lerobot/common/policies/act/configuration_act.py

@@ -1,8 +1,7 @@
-from dataclasses import dataclass, field
+from transformers.configuration_utils import PretrainedConfig
 
 
-@dataclass
-class ActionChunkingTransformerConfig:
+class ActionChunkingTransformerConfig(PretrainedConfig):
     """Configuration class for the Action Chunking Transformers policy.
 
     Defaults are configured for training on bimanual Aloha tasks like "insertion" or "transfer".
@@ -55,37 +54,41 @@ class ActionChunkingTransformerConfig:
         dropout: Dropout to use in the transformer layers (see code for details).
         kl_weight: The weight to use for the KL-divergence component of the loss if the variational objective
             is enabled. Loss is then calculated as: `reconstruction_loss + kl_weight * kld_loss`.
-    """
+
+        Example:
+
+        ```python
+        >>> from lerobot import ActionChunkingTransformerConfig
+
+        >>> # Initializing an ACT style configuration
+        >>> configuration = ActionChunkingTransformerConfig()
+
+        >>> # Initializing a model (with random weights) from the ACT style configuration
+        >>> model = ActionChunkingTransformerPolicy(configuration)
+
+        >>> # Accessing the model configuration
+        >>> configuration = model.config
+        ```"""
 
     # Input / output structure.
     n_obs_steps: int = 1
     chunk_size: int = 100
     n_action_steps: int = 100
 
-    input_shapes: dict[str, list[str]] = field(
-        default_factory=lambda: {
-            "observation.images.top": [3, 480, 640],
-            "observation.state": [14],
-        }
-    )
-    output_shapes: dict[str, list[str]] = field(
-        default_factory=lambda: {
-            "action": [14],
-        }
-    )
+    input_shapes: dict[str, list[str]] = {
+        "observation.images.top": [3, 480, 640],
+        "observation.state": [14],
+    }
+
+    output_shapes: dict[str, list[str]] = {"action": [14]}
 
     # Normalization / Unnormalization
-    normalize_input_modes: dict[str, str] = field(
-        default_factory=lambda: {
-            "observation.image": "mean_std",
-            "observation.state": "mean_std",
-        }
-    )
-    unnormalize_output_modes: dict[str, str] = field(
-        default_factory=lambda: {
-            "action": "mean_std",
-        }
-    )
+    normalize_input_modes: dict[str, str] = {
+        "observation.image": "mean_std",
+        "observation.state": "mean_std",
+    }
+
+    unnormalize_output_modes: dict[str, str] = {"action": "mean_std"}
 
     # Architecture.
     # Vision backbone.