Makes all configurations in locomotion velocity task consistent (#284)

# Description

This MR started with fixing the Unitree A1 environment configuration.
The asset has the name "trunk" instead of "base" so had to be adapted in
the code.

Additionally, all the ANYmal environments were following a different
hierarchy system. This MR makes the inheritance tree more consistent
across all environments.

## Type of change

- Bug fix (non-breaking change which fixes an issue)

## Screenshots

All the new quadrupeds together:

![leg-suite](https://github.com/isaac-orbit/orbit/assets/12863862/3721e66b-249d-4bee-9ec5-2026c7654bc5)

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./orbit.sh --format`
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

source/extensions/omni.isaac.orbit/config/extension.toml

 [package]
 
 # Note: Semantic Versioning is used: https://semver.org/
-version = "0.10.2"
+version = "0.10.3"
 
 # Description
 title = "ORBIT framework for Robot Learning"

source/extensions/omni.isaac.orbit/docs/CHANGELOG.rst

 Changelog
 ---------
 
+0.10.3 (2023-12-12)
+~~~~~~~~~~~~~~~~~~~
+
+Added
+^^^^^
+
+* Added the attribute :attr:`omni.isaac.orbit.actuators.ActuatorNetMLPCfg.input_order`
+  to specify the order of the input tensors to the MLP network.
+
+Fixed
+^^^^^
+
+* Fixed computation of metrics for the velocity command term. Earlier, the norm was being computed
+  over the entire batch instead of the last dimension.
+* Fixed the clipping inside the :class:`omni.isaac.orbit.actuators.DCMotor` class. Earlier, it was
+  not able to handle the case when configured saturation limit was set to None.
+
+
 0.10.2 (2023-12-12)
 ~~~~~~~~~~~~~~~~~~~
 

source/extensions/omni.isaac.orbit/omni/isaac/orbit/actuators/actuator_cfg.py

@@ -7,6 +7,7 @@ from __future__ import annotations
 
 from dataclasses import MISSING
 from typing import Iterable
+from typing_extensions import Literal
 
 from omni.isaac.orbit.utils import configclass
 
@@ -137,6 +138,16 @@ class ActuatorNetMLPCfg(DCMotorCfg):
     """Scaling of the joint velocities input to the network."""
     torque_scale: float = MISSING
     """Scaling of the joint efforts output from the network."""
+
+    input_order: Literal["pos_vel", "vel_pos"] = MISSING
+    """Order of the inputs to the network.
+
+    The order can be one of the following:
+
+    * ``"pos_vel"``: joint position errors followed by joint velocities
+    * ``"vel_pos"``: joint velocities followed by joint position errors
+    """
+
     input_idx: Iterable[int] = MISSING
     """
     Indices of the actuator history buffer passed as inputs to the network.

source/extensions/omni.isaac.orbit/omni/isaac/orbit/actuators/actuator_net.py

@@ -160,16 +160,23 @@ class ActuatorNetMLP(DCMotor):
         # compute network inputs
         # -- positions
         pos_input = torch.cat([self._joint_pos_error_history[:, i].unsqueeze(2) for i in self.cfg.input_idx], dim=2)
-        pos_input = pos_input.reshape(self._num_envs * self.num_joints, -1)
+        pos_input = pos_input.view(self._num_envs * self.num_joints, -1)
         # -- velocity
         vel_input = torch.cat([self._joint_vel_history[:, i].unsqueeze(2) for i in self.cfg.input_idx], dim=2)
-        vel_input = vel_input.reshape(self._num_envs * self.num_joints, -1)
+        vel_input = vel_input.view(self._num_envs * self.num_joints, -1)
         # -- scale and concatenate inputs
-        network_input = torch.cat([vel_input * self.cfg.vel_scale, pos_input * self.cfg.pos_scale], dim=1)
+        if self.cfg.input_order == "pos_vel":
+            network_input = torch.cat([pos_input * self.cfg.pos_scale, vel_input * self.cfg.vel_scale], dim=1)
+        elif self.cfg.input_order == "vel_pos":
+            network_input = torch.cat([vel_input * self.cfg.vel_scale, pos_input * self.cfg.pos_scale], dim=1)
+        else:
+            raise ValueError(
+                f"Invalid input order for MLP actuator net: {self.cfg.input_order}. Must be 'pos_vel' or 'vel_pos'."
+            )
 
         # run network inference
-        torques = self.network(network_input).reshape(self._num_envs, self.num_joints)
-        self.computed_effort = torques.reshape(self._num_envs, self.num_joints) * self.cfg.torque_scale
+        torques = self.network(network_input).view(self._num_envs, self.num_joints)
+        self.computed_effort = torques.view(self._num_envs, self.num_joints) * self.cfg.torque_scale
 
         # clip the computed effort based on the motor limits
         self.applied_effort = self._clip_effort(self.computed_effort)

source/extensions/omni.isaac.orbit/omni/isaac/orbit/actuators/actuator_pd.py

@@ -210,10 +210,10 @@ class DCMotor(IdealPDActuator):
     def _clip_effort(self, effort: torch.Tensor) -> torch.Tensor:
         # compute torque limits
         # -- max limit
-        max_effort = self.cfg.saturation_effort * (1.0 - self._joint_vel / self.velocity_limit)
+        max_effort = self._saturation_effort * (1.0 - self._joint_vel / self.velocity_limit)
         max_effort = torch.clip(max_effort, min=self._zeros_effort, max=self.effort_limit)
         # -- min limit
-        min_effort = self.cfg.saturation_effort * (-1.0 - self._joint_vel / self.velocity_limit)
+        min_effort = self._saturation_effort * (-1.0 - self._joint_vel / self.velocity_limit)
         min_effort = torch.clip(min_effort, min=-self.effort_limit, max=self._zeros_effort)
 
         # clip the torques based on the motor limits

source/extensions/omni.isaac.orbit/omni/isaac/orbit/assets/config/unitree.py

@@ -7,17 +7,43 @@
 
 The following configurations are available:
 
-* :obj:`UNITREE_A1_CFG`: Unitree A1 robot with simple PD controller for the legs
+* :obj:`UNITREE_A1_CFG`: Unitree A1 robot with DC motor model for the legs
+* :obj:`UNITREE_GO1_CFG`: Unitree Go1 robot with actuator net model for the legs
+* :obj:`UNITREE_GO2_CFG`: Unitree Go2 robot with DC motor model for the legs
 
 Reference: https://github.com/unitreerobotics/unitree_ros
 """
 
 import omni.isaac.orbit.sim as sim_utils
-from omni.isaac.orbit.actuators import DCMotorCfg
+from omni.isaac.orbit.actuators import ActuatorNetMLPCfg, DCMotorCfg
 from omni.isaac.orbit.utils.assets import ISAAC_ORBIT_NUCLEUS_DIR
 
 from ..articulation import ArticulationCfg
 
+##
+# Configuration - Actuators.
+##
+
+GO1_ACTUATOR_CFG = ActuatorNetMLPCfg(
+    joint_names_expr=[".*_hip_joint", ".*_thigh_joint", ".*_calf_joint"],
+    network_file=f"{ISAAC_ORBIT_NUCLEUS_DIR}/ActuatorNets/Unitree/unitree_go1.pt",
+    pos_scale=-1.0,
+    vel_scale=1.0,
+    torque_scale=1.0,
+    input_order="pos_vel",
+    input_idx=[0, 1, 2],
+    effort_limit=23.7,  # taken from spec sheet
+    velocity_limit=30.0,  # taken from spec sheet
+    saturation_effort=23.7,  # same as effort limit
+)
+"""Configuration of Go1 actuators using MLP model.
+
+Actuator specifications: https://shop.unitree.com/products/go1-motor
+
+This model is taken from: https://github.com/Improbable-AI/walk-these-ways
+"""
+
+
 ##
 # Configuration
 ##
@@ -54,7 +80,7 @@ UNITREE_A1_CFG = ArticulationCfg(
     soft_joint_pos_limit_factor=0.9,
     actuators={
         "base_legs": DCMotorCfg(
-            joint_names_expr=[".*"],
+            joint_names_expr=[".*_hip_joint", ".*_thigh_joint", ".*_calf_joint"],
             effort_limit=33.5,
             saturation_effort=33.5,
             velocity_limit=21.0,
@@ -68,3 +94,83 @@ UNITREE_A1_CFG = ArticulationCfg(
 
 Note: Specifications taken from: https://www.trossenrobotics.com/a1-quadruped#specifications
 """
+
+
+UNITREE_GO1_CFG = ArticulationCfg(
+    spawn=sim_utils.UsdFileCfg(
+        usd_path=f"{ISAAC_ORBIT_NUCLEUS_DIR}/Robots/Unitree/Go1/go1.usd",
+        activate_contact_sensors=True,
+        rigid_props=sim_utils.RigidBodyPropertiesCfg(
+            disable_gravity=False,
+            retain_accelerations=False,
+            linear_damping=0.0,
+            angular_damping=0.0,
+            max_linear_velocity=1000.0,
+            max_angular_velocity=1000.0,
+            max_depenetration_velocity=1.0,
+        ),
+        articulation_props=sim_utils.ArticulationRootPropertiesCfg(
+            enabled_self_collisions=False, solver_position_iteration_count=4, solver_velocity_iteration_count=0
+        ),
+    ),
+    init_state=ArticulationCfg.InitialStateCfg(
+        pos=(0.0, 0.0, 0.34),
+        joint_pos={
+            ".*L_hip_joint": 0.1,
+            ".*R_hip_joint": -0.1,
+            "F[L,R]_thigh_joint": 0.8,
+            "R[L,R]_thigh_joint": 1.0,
+            ".*_calf_joint": -1.5,
+        },
+        joint_vel={".*": 0.0},
+    ),
+    soft_joint_pos_limit_factor=0.9,
+    actuators={
+        "base_legs": GO1_ACTUATOR_CFG,
+    },
+)
+"""Configuration of Unitree Go1 using MLP-based actuator model."""
+
+
+UNITREE_GO2_CFG = ArticulationCfg(
+    spawn=sim_utils.UsdFileCfg(
+        usd_path=f"{ISAAC_ORBIT_NUCLEUS_DIR}/Robots/Unitree/Go2/go2.usd",
+        activate_contact_sensors=True,
+        rigid_props=sim_utils.RigidBodyPropertiesCfg(
+            disable_gravity=False,
+            retain_accelerations=False,
+            linear_damping=0.0,
+            angular_damping=0.0,
+            max_linear_velocity=1000.0,
+            max_angular_velocity=1000.0,
+            max_depenetration_velocity=1.0,
+        ),
+        articulation_props=sim_utils.ArticulationRootPropertiesCfg(
+            enabled_self_collisions=False, solver_position_iteration_count=4, solver_velocity_iteration_count=0
+        ),
+    ),
+    init_state=ArticulationCfg.InitialStateCfg(
+        pos=(0.0, 0.0, 0.34),
+        joint_pos={
+            ".*L_hip_joint": 0.1,
+            ".*R_hip_joint": -0.1,
+            "F[L,R]_thigh_joint": 0.8,
+            "R[L,R]_thigh_joint": 1.0,
+            ".*_calf_joint": -1.5,
+        },
+        joint_vel={".*": 0.0},
+    ),
+    soft_joint_pos_limit_factor=0.9,
+    actuators={
+        "base_legs": DCMotorCfg(
+            joint_names_expr=[".*_hip_joint", ".*_thigh_joint", ".*_calf_joint"],
+            effort_limit=23.5,
+            saturation_effort=23.5,
+            velocity_limit=30.0,
+            stiffness=25.0,
+            damping=0.5,
+            friction=0.0,
+        ),
+    },
+)
+"""Configuration of Unitree Go2 using DC-Motor actuator model."""

source/extensions/omni.isaac.orbit/omni/isaac/orbit/envs/mdp/commands/velocity_command.py

@@ -132,12 +132,13 @@ class UniformVelocityCommand(CommandTerm):
     def _update_metrics(self):
         # time for which the command was executed
         max_command_time = self.cfg.resampling_time_range[1]
+        max_command_step = max_command_time / self._env.step_dt
         # logs data
         self.metrics["error_vel_xy"] += (
-            torch.norm(self.vel_command_b[:, :2] - self.robot.data.root_lin_vel_b[:, :2]) / max_command_time
+            torch.norm(self.vel_command_b[:, :2] - self.robot.data.root_lin_vel_b[:, :2], dim=-1) / max_command_step
         )
         self.metrics["error_vel_yaw"] += (
-            torch.abs(self.vel_command_b[:, 2] - self.robot.data.root_ang_vel_b[:, 2]) / max_command_time
+            torch.abs(self.vel_command_b[:, 2] - self.robot.data.root_ang_vel_b[:, 2]) / max_command_step
         )
 
     def _set_debug_vis_impl(self, debug_vis: bool):

source/extensions/omni.isaac.orbit_tasks/omni/isaac/orbit_tasks/locomotion/velocity/config/anymal_b/flat_env_cfg.py

@@ -5,22 +5,15 @@
 
 from omni.isaac.orbit.utils import configclass
 
-from omni.isaac.orbit_tasks.locomotion.velocity.velocity_env_cfg import LocomotionVelocityRoughEnvCfg
-
-##
-# Pre-defined configs
-##
-from omni.isaac.orbit.assets.config.anymal import ANYMAL_B_CFG  # isort: skip
+from .rough_env_cfg import AnymalBRoughEnvCfg
 
 
 @configclass
-class AnymalBFlatEnvCfg(LocomotionVelocityRoughEnvCfg):
+class AnymalBFlatEnvCfg(AnymalBRoughEnvCfg):
     def __post_init__(self):
         # post init of parent
         super().__post_init__()
 
-        # switch robot to anymal-d
-        self.scene.robot = ANYMAL_B_CFG.replace(prim_path="{ENV_REGEX_NS}/Robot")
         # override rewards
         self.rewards.flat_orientation_l2.weight = -5.0
         self.rewards.dof_torques_l2.weight = -2.5e-5

source/extensions/omni.isaac.orbit_tasks/omni/isaac/orbit_tasks/locomotion/velocity/config/anymal_c/flat_env_cfg.py

@@ -5,22 +5,15 @@
 
 from omni.isaac.orbit.utils import configclass
 
-from omni.isaac.orbit_tasks.locomotion.velocity.velocity_env_cfg import LocomotionVelocityRoughEnvCfg
-
-##
-# Pre-defined configs
-##
-from omni.isaac.orbit.assets.config.anymal import ANYMAL_C_CFG  # isort: skip
+from .rough_env_cfg import AnymalCRoughEnvCfg
 
 
 @configclass
-class AnymalCFlatEnvCfg(LocomotionVelocityRoughEnvCfg):
+class AnymalCFlatEnvCfg(AnymalCRoughEnvCfg):
     def __post_init__(self):
         # post init of parent
         super().__post_init__()
 
-        # switch robot to anymal-c
-        self.scene.robot = ANYMAL_C_CFG.replace(prim_path="{ENV_REGEX_NS}/Robot")
         # override rewards
         self.rewards.flat_orientation_l2.weight = -5.0
         self.rewards.dof_torques_l2.weight = -2.5e-5

source/extensions/omni.isaac.orbit_tasks/omni/isaac/orbit_tasks/locomotion/velocity/config/anymal_d/flat_env_cfg.py

@@ -5,22 +5,15 @@
 
 from omni.isaac.orbit.utils import configclass
 
-from omni.isaac.orbit_tasks.locomotion.velocity.velocity_env_cfg import LocomotionVelocityRoughEnvCfg
-
-##
-# Pre-defined configs
-##
-from omni.isaac.orbit.assets.config.anymal import ANYMAL_D_CFG  # isort: skip
+from .rough_env_cfg import AnymalDRoughEnvCfg
 
 
 @configclass
-class AnymalDFlatEnvCfg(LocomotionVelocityRoughEnvCfg):
+class AnymalDFlatEnvCfg(AnymalDRoughEnvCfg):
     def __post_init__(self):
         # post init of parent
         super().__post_init__()
 
-        # switch robot to anymal-d
-        self.scene.robot = ANYMAL_D_CFG.replace(prim_path="{ENV_REGEX_NS}/Robot")
         # override rewards
         self.rewards.flat_orientation_l2.weight = -5.0
         self.rewards.dof_torques_l2.weight = -2.5e-5

source/extensions/omni.isaac.orbit_tasks/omni/isaac/orbit_tasks/locomotion/velocity/config/unitree_a1/rough_env_cfg.py

@@ -20,6 +20,7 @@ class UnitreeA1RoughEnvCfg(LocomotionVelocityRoughEnvCfg):
         super().__post_init__()
 
         self.scene.robot = UNITREE_A1_CFG.replace(prim_path="{ENV_REGEX_NS}/Robot")
+        self.scene.height_scanner.prim_path = "{ENV_REGEX_NS}/Robot/trunk"
         # scale down the terrains because the robot is small
         self.scene.terrain.terrain_generator.sub_terrains["boxes"].grid_height_range = (0.025, 0.1)
         self.scene.terrain.terrain_generator.sub_terrains["random_rough"].noise_range = (0.01, 0.06)
@@ -30,7 +31,9 @@ class UnitreeA1RoughEnvCfg(LocomotionVelocityRoughEnvCfg):
 
         # randomization
         self.randomization.push_robot = None
-        self.randomization.add_base_mass = None
+        self.randomization.add_base_mass.params["mass_range"] = (-1.0, 3.0)
+        self.randomization.add_base_mass.params["asset_cfg"].body_names = "trunk"
+        self.randomization.base_external_force_torque.params["asset_cfg"].body_names = "trunk"
         self.randomization.reset_robot_joints.params["position_range"] = (1.0, 1.0)
         self.randomization.reset_base.params = {
             "pose_range": {"x": (-0.5, 0.5), "y": (-0.5, 0.5), "yaw": (-3.14, 3.14)},
@@ -45,7 +48,7 @@ class UnitreeA1RoughEnvCfg(LocomotionVelocityRoughEnvCfg):
         }
 
         # rewards
-        self.rewards.feet_air_time.params["sensor_cfg"].body_names = ".*_calf"
+        self.rewards.feet_air_time.params["sensor_cfg"].body_names = ".*_foot"
         self.rewards.feet_air_time.weight = 0.01
         self.rewards.undesired_contacts = None
         self.rewards.dof_torques_l2.weight = -0.0002
@@ -53,6 +56,9 @@ class UnitreeA1RoughEnvCfg(LocomotionVelocityRoughEnvCfg):
         self.rewards.track_ang_vel_z_exp.weight = 0.75
         self.rewards.dof_acc_l2.weight = -2.5e-7
 
+        # terminations
+        self.terminations.base_contact.params["sensor_cfg"].body_names = "trunk"
+
 
 @configclass
 class UnitreeA1RoughEnvCfg_PLAY(UnitreeA1RoughEnvCfg):

source/extensions/omni.isaac.orbit_tasks/omni/isaac/orbit_tasks/locomotion/velocity/velocity_env_cfg.py

@@ -235,7 +235,7 @@ class RewardsCfg:
         func=mdp.feet_air_time,
         weight=0.5,
         params={
-            "sensor_cfg": SceneEntityCfg("contact_forces", body_names=".*SHANK"),
+            "sensor_cfg": SceneEntityCfg("contact_forces", body_names=".*FOOT"),
             "command_name": "base_velocity",
             "threshold": 0.5,
         },
@@ -278,7 +278,7 @@ class LocomotionVelocityRoughEnvCfg(RLTaskEnvCfg):
     """Configuration for the locomotion velocity-tracking environment."""
 
     # Scene settings
-    scene: MySceneCfg = MySceneCfg(num_envs=4096, env_spacing=2.5, replicate_physics=False)
+    scene: MySceneCfg = MySceneCfg(num_envs=4096, env_spacing=2.5)
     # Basic settings
     observations: ObservationsCfg = ObservationsCfg()
     actions: ActionsCfg = ActionsCfg()

source/standalone/demos/quadrupeds.py

@@ -45,7 +45,7 @@ import omni.isaac.core.utils.prims as prim_utils
 import omni.isaac.orbit.sim as sim_utils
 from omni.isaac.orbit.assets import Articulation
 from omni.isaac.orbit.assets.config.anymal import ANYMAL_B_CFG, ANYMAL_C_CFG, ANYMAL_D_CFG
-from omni.isaac.orbit.assets.config.unitree import UNITREE_A1_CFG
+from omni.isaac.orbit.assets.config.unitree import UNITREE_A1_CFG, UNITREE_GO1_CFG, UNITREE_GO2_CFG
 
 
 def define_origins(num_origins: int, spacing: float) -> list[list[float]]:
@@ -74,7 +74,7 @@ def design_scene() -> tuple[dict, list[list[float]]]:
 
     # Create separate groups called "Origin1", "Origin2", "Origin3"
     # Each group will have a mount and a robot on top of it
-    origins = define_origins(num_origins=4, spacing=1.25)
+    origins = define_origins(num_origins=6, spacing=1.25)
 
     # Origin 1 with Anymal B
     prim_utils.create_prim("/World/Origin1", "Xform", translation=origins[0])
@@ -96,8 +96,25 @@ def design_scene() -> tuple[dict, list[list[float]]]:
     # -- Robot
     unitree_a = Articulation(UNITREE_A1_CFG.replace(prim_path="/World/Origin4/Robot"))
 
+    # Origin 5 with Unitree Go1
+    prim_utils.create_prim("/World/Origin5", "Xform", translation=origins[4])
+    # -- Robot
+    unitree_go1 = Articulation(UNITREE_GO1_CFG.replace(prim_path="/World/Origin5/Robot"))
+
+    # Origin 6 with Unitree Go2
+    prim_utils.create_prim("/World/Origin6", "Xform", translation=origins[5])
+    # -- Robot
+    unitree_go2 = Articulation(UNITREE_GO2_CFG.replace(prim_path="/World/Origin6/Robot"))
+
     # return the scene information
-    scene_entities = {"anymal_b": anymal_b, "anymal_c": anymal_c, "anymal_d": anymal_d, "unitree_a": unitree_a}
+    scene_entities = {
+        "anymal_b": anymal_b,
+        "anymal_c": anymal_c,
+        "anymal_d": anymal_d,
+        "unitree_a": unitree_a,
+        "unitree_go1": unitree_go1,
+        "unitree_go2": unitree_go2,
+    }
     return scene_entities, origins