use official unitree motor as default; disable randomized action delay env; update readme.

README.md

@@ -180,17 +180,15 @@ xml_path: "{ROOT_DIR}/resources/go2/your-custom-scene.xml"
 
 ## Differences from `go2_rl_gym`
 
-- Different tracking reward formulation (fixed sigma vs. dynamic sigma)
-- Different rewards:
+- Motor:
+  - use official unitree motor model instead of simple PD controller
+- Rewards:
+  - different tracking reward form (fixed sigma vs. dynamic sigma)
   - lower joint_acc_l2 weight in Lab due to physics-step level implementation and sensitivity to outliers
   - extra joint_pos_penalty_l1 reward in Lab due to better performance
-- Lack domain_rand: randomize_motor_strength
-
----
-
-## TODO
-
-- Try replacing ActionManager-level delay with `DelayedPDActuatorCfg` or `UnitreeActuatorCfg_Go2HV`, and make sure the randomization of motor parameters  works correctly.
+- Domain randomization: 
+  - no randomized action delay, use motor-level delay instead
+  - no motor strength randomization due to implementation constraints in Lab.
 
 ---
 

source/robot_lab/robot_lab/tasks/go2/__init__.py

@@ -19,8 +19,8 @@ from isaaclab_tasks.utils import import_packages
 ##
 gym.register(
     id="RobotLab-Go2-v0",
-    # entry_point="robot_lab.tasks.go2.env.go2_env:Go2Env",
-    entry_point="robot_lab.tasks.go2.env.go2_env:ActionDelayGo2Env",
+    entry_point="robot_lab.tasks.go2.env.go2_env:Go2Env",
+    # entry_point="robot_lab.tasks.go2.env.go2_env:ActionDelayGo2Env", # using motor-level delay, so disabled env-level delay
     disable_env_checker=True,
     kwargs={
         "env_cfg_entry_point": f"{__name__}.env_cfg:Go2EnvCfg",

source/robot_lab/robot_lab/tasks/go2/env_cfg.py

@@ -60,7 +60,7 @@ class Go2SceneCfg(InteractiveSceneCfg):
         debug_vis=False
     )
 
-    robot: ArticulationCfg = GO2_CFG_ROBOTLAB.replace(prim_path="{ENV_REGEX_NS}/Robot")
+    robot: ArticulationCfg = GO2_CFG_UNITREE.replace(prim_path="{ENV_REGEX_NS}/Robot")
 
     height_scanner = RayCasterCfg(
         prim_path="{ENV_REGEX_NS}/Robot/base",