Port SAC WIP (#581)

Co-authored-by: KeWang1017 <ke.wang@helloleap.ai>

lerobot/common/policies/sac/configuration_sac.py

@@ -0,0 +1,39 @@
+#!/usr/bin/env python
+
+# Copyright 2024 The HuggingFace Inc. team. 
+# All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from dataclasses import dataclass
+
+
+@dataclass
+class SACConfig:
+    discount = 0.99
+    temperature_init = 1.0
+    num_critics = 2
+    critic_lr = 3e-4
+    actor_lr = 3e-4
+    critic_network_kwargs = {
+            "hidden_dims": [256, 256],
+            "activate_final": True,
+        }
+    actor_network_kwargs = {
+            "hidden_dims": [256, 256],
+            "activate_final": True,
+        }
+    policy_kwargs = {
+            "tanh_squash_distribution": True,
+            "std_parameterization": "uniform",
+        }