Collect liquid samples and deploy sensors at ports

Main concepts:

1. Behavior trees for managing multiple robot navigation and arm manipulation actions through Finite State Machines.
2. ROS 2 for the navigation and manipulation nodes.
3. Nav2 is used for navigation.
4. MoveIt 2 is used for manipulation.

Working example of Behavior Tree: https://www.youtube.com/watch?v=NtHkbNBGDB4

How to run:

1. For simulation only: After sourcing the ~/colcon_ws (usual command . install/setup.bash) in one terminal run ros2 launch icclab_summit_xl summit_xl_simulation.launch.py.
2. In another similar sourced terminal, run ros2 launch icclab_summit_xl summit_xl_move_it.launch.py use_sim_time:=true | grep -v moveit_robot_model.robot_model. use_sim_time:=true is default for simulation, but when working with the real arm put use_sim_time:=false.
3. For running the Behavior Tree first clone, build and source this GitHub repo in your ROS 2 workspace, for example ~/rap/gaurav_ws$. Then run ros2 launch liquid_pickup liquid_pickup_launch.py. For simulation and real robot, we should switch between use_sim_time:=true and use_sim_time:=false in the launch file, for example here.
4. For providing a custom Behavior Tree (BT) XML to the BT node, place your XML file in config directory of this repo. Then this BT Tree could be provided to the BT node parameter via launch, for example here.
5. For visualizing the BT install Groot2, and run ./groot2 in the installed directory, for example ~/Groot2/bin.