Create Workzone Boundary Detection ROS Node

[nlitz88]

Basically, we need a ROS node that takes the OpenCV code we have written and wraps it up in a ROS node so that it can ingest 2D costmap images with bounding boxes (or whatever format the data comes in as) and spit out a 2D occupancy grid OR image (or whatever we decide on) with the workzone segmented.

Some rough ideas/requirements/notes:

• Probably fastest to implement this in Python: https://docs.ros.org/en/humble/Tutorials/Beginner-Client-Libraries/Writing-A-Simple-Py-Publisher-And-Subscriber.html#writing-a-simple-publisher-and-subscriber-python, particularly because we're using OpenCV and the whole pipeline is already written in Python. Won't be blazingly fast--but it'll be lightyears faster than the BEVFusion node, so it's fine!
• If we decide our nodes our going to be sending/receiving images rather than OccupancyGrid messages, probably want to use the sensor_msgs/Image message
• While it's not critical, as far as how to structure this: Create a new ROS package WITHIN THIS REPOSITORY -- don't make the package occupy / exist as the root of the repository. Not a huge deal, just good practice :)
• I will (probably) make a second ROS meta-package later that we use to launch all the nodes in the pipeline--and I will also probably create that in this repository. That'll contain a launch file to launch the nuScenes BEVFusion wrapper, the BEVFusion node itself, our workzone detection node, and then maybe something like RQT or RVIZ to visualize what's going on. UPDATE: https://github.com/nlitz88/workzone/issues/19

[CMUBOB97]

I have transferred the boundary_generation.py to a new python ROS2 galactic package.

The colcon build works with boundary_node generated and a launch file working.

Here are a few things to do today (Marked as # TODO in comments, Apr 19th, Friday):

• find function calls that convert between sensor_msgs/msg/Image and np.ndarray
• rewrite display image function so that intermediate outputs will be displayed as separate topics
• test the code with BEVFusion ROS TensorRT to see if it works

tag @nlitz88 for help because my GPU is SHHHHHHHHHHHHHHHHHHHHIT!!!!!!!!!!!

[nlitz88]

find function calls that convert between sensor_msgs/msg/Image and np.ndarray

I'm not 100% sure, but I believe this is what cv_bridge is for. Maybe that would work?

rewrite display image function so that intermediate outputs will be displayed as separate topics

Also, this is a great idea :100:

[nlitz88]

https://github.com/CMUBOB97/ROS2-Boundary-Segmentation

[nlitz88]

Tada!