[Question] moving problem of ridgeback_franka.

Question

I want to train RL model with mobile manipulator.

I found that ridgeback_franka robot asset is in the video of the orbit documentation.

Problem

The base is not moving even if i put the action.

But the manipulator is moving well. And i found that the '/world' prim is moving (assumed to the inverted direction of the action). I tried to make the '/world'(robot's world) to be fixed to the '/World'. But nothing made a good result.

I put a cube into '/world' to visualize the problem.

If i put a ground or something in the '/world' i can see it's moving relative to the action of the robot base.

https://github.com/NVIDIA-Omniverse/orbit/assets/20448909/4f89fb70-5df9-47e3-8a46-5e130ee88262

Is there any example code to use RL with Mobile Manipulator?

Code

orbit/source/extensions/omni.isaac.orbit/test/assets/check_ridgeback_franka.py

# Copyright (c) 2022-2024, The ORBIT Project Developers.
# All rights reserved.
#
# SPDX-License-Identifier: BSD-3-Clause

"""
This script demonstrates how to simulate a mobile manipulator.

.. code-block:: bash

    # Usage
    ./orbit.sh -p source/extensions/omni.isaac.orbit/test/assets/check_ridgeback_franka.py

"""

"""Launch Isaac Sim Simulator first."""

import argparse

from omni.isaac.orbit.app import AppLauncher

# add argparse arguments
parser = argparse.ArgumentParser(
    description="This script demonstrates how to simulate a mobile manipulator with dummy joints."
)
# append AppLauncher cli args
AppLauncher.add_app_launcher_args(parser)
# parse the arguments
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.isaac.orbit.sim as sim_utils
from omni.isaac.orbit.assets import Articulation

##
# Pre-defined configs
##
from omni.isaac.orbit_assets.ridgeback_franka import RIDGEBACK_FRANKA_PANDA_CFG  # isort:skip

def design_scene():
    """Designs the scene."""
    # Ground-plane
    cfg = sim_utils.GroundPlaneCfg()
    cfg.func("/World/defaultGroundPlane", cfg)
    # Lights
    cfg = sim_utils.DistantLightCfg(intensity=3000.0, color=(0.75, 0.75, 0.75))
    cfg.func("/World/Light", cfg)
    # add robots and return them
    return add_robots()

def add_robots() -> Articulation:
    """Adds robots to the scene."""
    robot_cfg = RIDGEBACK_FRANKA_PANDA_CFG
    # -- Spawn robot
    robot_cfg.spawn.func("/World/Robot_1", robot_cfg.spawn, translation=(0.0, -1.0, 0.0))
    robot_cfg.spawn.func("/World/Robot_2", robot_cfg.spawn, translation=(0.0, 1.0, 0.0))
    # -- Create interface
    robot = Articulation(cfg=robot_cfg.replace(prim_path="/World/Robot.*"))

    return robot

def run_simulator(sim: sim_utils.SimulationContext, robot: Articulation):
    """Runs the simulator by applying actions to the robot at every time-step"""
    # dummy action
    actions = robot.data.default_joint_pos.clone()

    print(robot.data.joint_names)

    target_base_names = [
        "dummy_base_prismatic_x_joint",
        "dummy_base_prismatic_y_joint",
        "dummy_base_revolute_z_joint"
    ]

    target_base_index = [robot.data.joint_names.index(name) for name in target_base_names]

    # Define simulation stepping
    sim_dt = sim.get_physics_dt()
    # episode counter
    sim_time = 0.0
    ep_step_count = 0
    # Simulate physics
    while simulation_app.is_running():
        # reset
        if ep_step_count % 1000 == 0:
            # reset counters
            sim_time = 0.0
            ep_step_count = 0
            # reset dof state
            joint_pos, joint_vel = robot.data.default_joint_pos.clone(), robot.data.default_joint_vel.clone()
            robot.write_joint_state_to_sim(joint_pos, joint_vel)
            # reset internals
            robot.reset()
            # reset command
            actions = torch.rand_like(robot.data.default_joint_pos) + robot.data.default_joint_pos
            # -- base
            actions[:, 0:3] = 0.0
            # -- gripper
            actions[:, -2:] = 0.04
            print("[INFO]: Resetting robots state...")
        # change the gripper action
        if ep_step_count % 200 == 0:
            # flip command for the gripper
            actions[:, -2:] = 0.0 if actions[0, -2] > 0.0 else 0.04
        # change the base action
        # -- forward and backward (x-axis)
        if ep_step_count == 200:
            actions[:, :3] = 0.0
            actions[:, 0] = 1.0
        if ep_step_count == 300:
            actions[:, :3] = 0.0
            actions[:, 0] = -1.0
        # -- right and left (y-axis)
        if ep_step_count == 400:
            actions[:, :3] = 0.0
            actions[:, 1] = 1.0
        if ep_step_count == 500:
            actions[:, :3] = 0.0
            actions[:, 1] = -1.0
        # -- turn right and left (z-axis)
        if ep_step_count == 600:
            actions[:, :3] = 0.0
            actions[:, 2] = 1.0
        if ep_step_count == 700:
            actions[:, :3] = 0.0
            actions[:, 2] = -1.0
        if ep_step_count == 900:
            actions[:, :3] = 0.0
            actions[:, 2] = 1.0
        # change the arm action
        if ep_step_count % 100:
            actions[:, 3:10] = torch.rand(robot.num_instances, 7, device=robot.device)
            actions[:, 3:10] += robot.data.default_joint_pos[:, 3:10]
        # apply action
        robot.set_joint_velocity_target(actions[:, :3], joint_ids=target_base_index)
        robot.set_joint_position_target(actions[:, 3:], joint_ids=[3, 4, 5, 6, 7, 8, 9, 10, 11])
        robot.write_data_to_sim()
        # perform step
        sim.step()
        # update sim-time
        sim_time += sim_dt
        ep_step_count += 1
        # update buffers
        robot.update(sim_dt)

def main():
    """Main function."""
    # Initialize the simulation context
    sim = sim_utils.SimulationContext(sim_utils.SimulationCfg())
    # Set main camera
    sim.set_camera_view([1.5, 1.5, 1.5], [0.0, 0.0, 0.0])
    # design scene
    robot = design_scene()
    # Play the simulator
    sim.reset()
    # Now we are ready!
    print("[INFO]: Setup complete...")
    # Run the simulator
    run_simulator(sim, robot)

if __name__ == "__main__":
    # run the main function
    main()
    # close sim app
    simulation_app.close()

isaac-sim / IsaacLab