switch back to average friction combine mode; remove domain rand: randomize_com_positions_other.

README.md

@@ -185,7 +185,6 @@ xml_path: "{ROOT_DIR}/resources/go2/your-custom-scene.xml"
   - 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
-- Extra domain_rand: randomize_com_positions_other (lead to better performance)
 
 ---
 

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

@@ -46,7 +46,7 @@ class Go2SceneCfg(InteractiveSceneCfg):
         max_init_terrain_level=5,
         collision_group=-1,
         physics_material=sim_utils.RigidBodyMaterialCfg(
-            friction_combine_mode="multiply",
+            friction_combine_mode="average",
             restitution_combine_mode="average",
             static_friction=1.0,
             dynamic_friction=1.0,
@@ -274,14 +274,6 @@ class EventCfg:
             "com_range": {"x": (-0.03, 0.03), "y": (-0.03, 0.03), "z": (-0.03, 0.03)},
         },
     )
-    randomize_com_positions_other = EventTerm(
-        func=mdp.randomize_rigid_body_com,
-        mode="startup",
-        params={
-            "asset_cfg": SceneEntityCfg("robot", body_names="^(?!.*base).*"),
-            "com_range": {"x": (-0.03, 0.03), "y": (-0.03, 0.03), "z": (-0.03, 0.03)},
-        },
-    )
     reset_robot_joints = EventTerm(
         func=mdp.reset_joints_by_scale,
         mode="reset",
@@ -328,8 +320,8 @@ class EventCfg:
         mode="startup",
         params={
             "asset_cfg": SceneEntityCfg("robot", body_names=".*"),
-            "static_friction_range": (0.5, 1.5),
-            "dynamic_friction_range": (0.5, 1.5),
+            "static_friction_range": (0.0, 2.0),
+            "dynamic_friction_range": (0.0, 2.0),
             "restitution_range": (0.0, 0.5),
             "num_buckets": 64,
             "make_consistent": True