Support Multi-Back for Demo Scripts (Part 2) and Unify Code Structure

scripts/demos/arl_robot_1.py

@@ -3,37 +3,42 @@
 #
 # SPDX-License-Identifier: BSD-3-Clause
 
-"""
-Script to view ARL Robot 1.
+"""Script to view ARL Robot 1.
+
+.. code-block:: bash
+
+    # Usage with default PhysX physics and default kit visualizer.
+    ./isaaclab.sh -p scripts/demos/arl_robot_1.py
+
+    # Usage with Newton visualizer and default PhysX physics.
+    ./isaaclab.sh -p scripts/demos/arl_robot_1.py --visualizer newton
 
-Launch Isaac Sim Simulator first.
 """
 
-# Create argparser
+"""Parse CLI first so we can decide whether to launch Isaac Sim Kit."""
+
 import argparse
 
-from isaaclab.app import AppLauncher
+from isaaclab.app import add_launcher_args, launch_simulation
 
-parser = argparse.ArgumentParser(description="View ARL Robot 1 with Lee Position Controller.")
-# append AppLauncher cli args
-AppLauncher.add_app_launcher_args(parser)
+parser = argparse.ArgumentParser(
+    description="View ARL Robot 1 with Lee Position Controller.",
+    conflict_handler="resolve",
+)
+parser.add_argument("--physics", default="physx", choices=["physx"], help="Physics backend.")
+add_launcher_args(parser)
+parser.set_defaults(visualizer=["kit"])
 args_cli = parser.parse_args()
 
-# launch omniverse app
-app_launcher = AppLauncher(args_cli)
-simulation_app = app_launcher.app
-
-"""Rest everything follows."""
-
 import torch
 
-import omni.usd
-from pxr import Gf, UsdLux
-
 import isaaclab.sim as sim_utils
-from isaaclab.sim import SimulationContext
 
-from isaaclab_contrib.assets import Multirotor
+##
+# Pre-defined configs
+##
+from isaaclab.physics import PhysicsCfg
+
 from isaaclab_contrib.controllers.lee_position_control import LeePosController
 from isaaclab_contrib.controllers.lee_position_control_cfg import LeePosControllerCfg
 
@@ -42,72 +47,68 @@
 
 def main():
     """Main function to spawn arl_robot_1."""
-
-    # Create simulation context
-    sim_cfg = sim_utils.SimulationCfg(dt=0.01)
-    sim = SimulationContext(sim_cfg)
-
-    # Create a dome light with light blue color
-    stage = omni.usd.get_context().get_stage()
-    dome_light = UsdLux.DomeLight.Define(stage, "/World/DomeLight")
-    dome_light.CreateColorAttr(Gf.Vec3f(0.53, 0.81, 0.92))  # Light blue
-    dome_light.CreateIntensityAttr(1000.0)
-
-    # Spawn ground plane
-    cfg = sim_utils.GroundPlaneCfg()
-    cfg.func("/World/defaultGroundPlane", cfg)
-
-    # Spawn robot
-    robot_cfg = ARL_ROBOT_1_CFG.replace(prim_path="/World/Robot")
-    robot_cfg.actuators["thrusters"].dt = sim_cfg.dt
-    robot = Multirotor(robot_cfg)
-
-    # Play the simulator
-    sim.reset()
-
-    # Create Lee position controller
-    controller_cfg = LeePosControllerCfg(
-        K_pos_range=((2.5, 2.5, 1.5), (3.5, 3.5, 2.0)),
-        K_vel_range=((2.5, 2.5, 1.5), (3.5, 3.5, 2.0)),
-        K_rot_range=((1.6, 1.6, 0.25), (1.85, 1.85, 0.4)),
-        K_angvel_range=((0.4, 0.4, 0.075), (0.5, 0.5, 0.09)),
-        max_inclination_angle_rad=1.0471975511965976,
-        max_yaw_rate=1.0471975511965976,
-    )
-    controller = LeePosController(controller_cfg, robot, num_envs=1, device=str(sim.device))
-
-    # Get allocation matrix and compute pseudoinverse
-    allocation_matrix = torch.tensor(robot_cfg.allocation_matrix, device=sim.device, dtype=torch.float32)
-    # allocation_matrix is (6, num_thrusters), we need pseudoinverse for wrench -> thrust
-    alloc_pinv = torch.linalg.pinv(allocation_matrix)  # Shape: (num_thrusters, 6)
-
-    # Position command: hover in place (zero position, zero yaw)
-    pos_command = torch.zeros((1, 4), device=sim.device)  # [x, y, z, yaw]
-    pos_command[0, 2] = 1.0  # Hover at 1 meter height
-
-    # Simulation loop
-    print("[INFO] Starting demo with Lee Position Controller. Press Ctrl+C to stop.")
-
-    while simulation_app.is_running():
-        # Compute wrench from velocity controller
-        wrench = controller.compute(pos_command)  # Shape: (1, 6)
-
-        # Allocate wrench to thrusters: thrust = pinv(A) @ wrench
-        thrust_cmd = torch.matmul(wrench, alloc_pinv.T)  # Shape: (1, num_thrusters)
-        thrust_cmd = thrust_cmd.clamp(min=0.0)  # Ensure non-negative thrust
-
-        # Apply thrust
-        robot.set_thrust_target(thrust_cmd)
-
-        # Step simulation
-        robot.write_data_to_sim()
-        sim.step()
-
-        # Update robot
-        robot.update(sim_cfg.dt)
-
-    # Cleanup
-    simulation_app.close()
+    with launch_simulation(cfg=PhysicsCfg(), launcher_args=args_cli) as physics_cfg:
+        # Create simulation context
+        sim_cfg = sim_utils.SimulationCfg(dt=0.01, device=args_cli.device, physics=physics_cfg)
+        sim = sim_utils.SimulationContext(sim_cfg)
+
+        # Create a dome light with light blue color
+        light_cfg = sim_utils.DomeLightCfg(intensity=1000.0, color=(0.53, 0.81, 0.92))
+        light_cfg.func("/World/DomeLight", light_cfg)
+
+        # Spawn ground plane
+        ground_cfg = sim_utils.GroundPlaneCfg()
+        ground_cfg.func("/World/defaultGroundPlane", ground_cfg)
+
+        # Spawn robot
+        robot_cfg = ARL_ROBOT_1_CFG.replace(prim_path="/World/Robot")
+        robot_cfg.actuators["thrusters"].dt = sim_cfg.dt
+        robot = robot_cfg.class_type(robot_cfg)
+
+        # Play the simulator
+        sim.reset()
+
+        # Create Lee position controller
+        controller_cfg = LeePosControllerCfg(
+            K_pos_range=((2.5, 2.5, 1.5), (3.5, 3.5, 2.0)),
+            K_vel_range=((2.5, 2.5, 1.5), (3.5, 3.5, 2.0)),
+            K_rot_range=((1.6, 1.6, 0.25), (1.85, 1.85, 0.4)),
+            K_angvel_range=((0.4, 0.4, 0.075), (0.5, 0.5, 0.09)),
+            max_inclination_angle_rad=1.0471975511965976,
+            max_yaw_rate=1.0471975511965976,
+        )
+        controller = LeePosController(controller_cfg, robot, num_envs=1, device=str(sim.device))
+
+        # Get allocation matrix and compute pseudoinverse
+        allocation_matrix = torch.tensor(robot_cfg.allocation_matrix, device=sim.device, dtype=torch.float32)
+        # allocation_matrix is (6, num_thrusters), we need pseudoinverse for wrench -> thrust
+        alloc_pinv = torch.linalg.pinv(allocation_matrix)  # Shape: (num_thrusters, 6)
+
+        # Position command: hover in place (zero position, zero yaw)
+        pos_command = torch.zeros((1, 4), device=sim.device)  # [x, y, z, yaw]
+        pos_command[0, 2] = 1.0  # Hover at 1 meter height
+
+        # Simulation loop
+        print("[INFO] Starting demo with Lee Position Controller. Press Ctrl+C to stop.")
+
+        # Step while a visualizer window is still open (or none exist, e.g. headless); works for kit and newton.
+        while sim.is_headless_or_exist_active_visualizer():
+            # Compute wrench from position controller
+            wrench = controller.compute(pos_command)  # Shape: (1, 6)
+
+            # Allocate wrench to thrusters: thrust = pinv(A) @ wrench
+            thrust_cmd = torch.matmul(wrench, alloc_pinv.T)  # Shape: (1, num_thrusters)
+            thrust_cmd = thrust_cmd.clamp(min=0.0)  # Ensure non-negative thrust
+
+            # Apply thrust
+            robot.set_thrust_target(thrust_cmd)
+
+            # Step simulation
+            robot.write_data_to_sim()
+            sim.step()
+
+            # Update robot
+            robot.update(sim_cfg.dt)
 
 
 if __name__ == "__main__":

scripts/demos/arms.py

@@ -3,8 +3,7 @@
 #
 # SPDX-License-Identifier: BSD-3-Clause
 
-"""
-This script demonstrates different single-arm manipulators.
+"""This script demonstrates different single-arm manipulators.
 
 .. code-block:: bash
 
@@ -60,7 +59,7 @@
 
 
 def define_origins(num_origins: int, spacing: float) -> list[list[float]]:
-    """Defines the origins of the the scene."""
+    """Defines the origins of the scene."""
     # create tensor based on number of environments
     env_origins = torch.zeros(num_origins, 3)
     # create a grid of origins

scripts/demos/bin_packing.py

@@ -50,20 +50,21 @@
 
 import torch
 
+import isaaclab.sim as sim_utils
+import isaaclab.utils.math as math_utils
+
 ##
 # Pre-defined configs
 ##
-from isaaclab_newton.physics import MJWarpSolverCfg, NewtonCfg
-
-import isaaclab.sim as sim_utils
-import isaaclab.utils.math as math_utils
 from isaaclab.assets import AssetBaseCfg, RigidObjectCfg, RigidObjectCollectionCfg
 from isaaclab.physics import PhysicsCfg
 from isaaclab.scene import InteractiveScene, InteractiveSceneCfg
 from isaaclab.utils import Timer
 from isaaclab.utils.assets import ISAAC_NUCLEUS_DIR
 from isaaclab.utils.configclass import configclass
 
+from isaaclab_newton.physics import MJWarpSolverCfg, NewtonCfg  # isort:skip
+
 if TYPE_CHECKING:
     from isaaclab.assets import RigidObjectCollection
 
@@ -348,7 +349,7 @@ def run_simulator(sim: sim_utils.SimulationContext, scene: InteractiveScene) ->
         scene.update(sim_dt)
 
 
-def main() -> None:
+def main():
     """Main function.
 
     Returns:

scripts/demos/bipeds.py

@@ -3,8 +3,7 @@
 #
 # SPDX-License-Identifier: BSD-3-Clause
 
-"""
-This script demonstrates how to simulate bipedal robots.
+"""This script demonstrates how to simulate bipedal robots.
 
 .. code-block:: bash