"package 'mujoco_robots' not found

[Combuster54]

Hello,

I was trying to runt he example with

ros2 launch mujoco_demo_robot cart_effort.launch.py

and I saw this message

[INFO] [launch]: All log files can be found below /home/combuster54/.ros/log/2025-06-23-15-17-31-585756-DESKTOP-LMQHD5S-93982
[INFO] [launch]: Default logging verbosity is set to INFO
[ERROR] [launch]: Caught exception in launch (see debug for traceback): "package 'mujoco_robots' not found, searching: ['/home/combuster54/unitree_go2/ros2_ws/install/mujoco_ros2_control', '/home/combuster54/unitree_go2/ros2_ws/install/mujoco_demo_robot', '/home/combuster54/unitree_go2/ros2_ws/install/mujoco_sim_ros2', '/home/combuster54/unitree_go2/ros2_ws/install/mujoco_ros2_control_demos', '/opt/ros/jazzy']"

I found a pkg with that name, but the description format is in ros1:
https://github.com/HoangGiang93/mujoco_robots

Any idea?

[rxdu]

Sorry for the confusion. The missing configuration file can be found here:

https://github.com/rxdu/mujoco_demo_robot/blob/main/config/cart_effort.yaml

So the solution is to change this line "https://github.com/rxdu/mujoco_demo_robot/blob/main/launch/cart_effort.launch.py#L28" from FindPackageShare('mujoco_robots'), to FindPackageShare('mujoco_demo_robot'),

I created mujoco_demo_robot repo and copied over files from mujoco_robots repo to make the demo setup complete, but didn't notice this inconsistency. I will update the demo repo to fix this error later.

The repo mujoco_robots is currently private as I use it for other purposes. It just contains more robot models, but requires some cleanup before it's ready to be made public.

[Combuster54]

Hi, thanks for it!

Now I've been running the first example and I see an issue.

combuster54@DESKTOP-LMQHD5S:~/unitree_go2/ros2_ws$ ros2 run mujoco_ros2_control_demos example_effort
[INFO] [1750734716.416119602] [effort_test_node]: node created
cannot publish data, at ./src/rmw_publish.cpp:66 during '__function__'
[ERROR] [1750734719.550548040] [effort_test_node.rclcpp]: Error in destruction of rcl subscription handle: Failed to delete datareader, at ./src/subscription.cpp:52, at ./src/rcl/subscription.c:200
cannot publish data, at ./src/rmw_publish.cpp:66 during '__function__'
Fail in delete datareader, at ./src/rmw_service.cpp:89 during '__function__'
[ros2run]: Segmentation fault

So I just change the code, here is the solution, If you want to solve this :D

#include <rclcpp/rclcpp.hpp>
#include <std_msgs/msg/float64_multi_array.hpp>
#include <chrono>
#include <thread>

int main(int argc, char * argv[])
{
  rclcpp::init(argc, argv);
  auto node = std::make_shared<rclcpp::Node>("effort_test_node");

  auto publisher = node->create_publisher<std_msgs::msg::Float64MultiArray>(
    "/effort_controller/commands", 10);

  RCLCPP_INFO(node->get_logger(), "node created");

  std_msgs::msg::Float64MultiArray commands;
  using namespace std::chrono_literals;

  std::vector<double> values = {0, 100, -200, 0};

  for (double v : values) {
    commands.data.clear();
    commands.data.push_back(v);
    publisher->publish(commands);
    rclcpp::spin_some(node);
    std::this_thread::sleep_for(1s);
  }

  rclcpp::shutdown();
  return 0;
}

combuster54@DESKTOP-LMQHD5S:~/unitree_go2/ros2_ws$ ros2 run mujoco_ros2_control_demos example_effort
[INFO] [1750735159.764378464] [effort_test_node]: node created
combuster54@DESKTOP-LMQHD5S:~/unitree_go2/ros2_ws$ 

Thanks for your help, now I want to try with unitree_go2, so I'm going to update it.