Earlier, we have created a 2.5D world. It has hills. It has roads. It has textures... Eventually it will have caves, trees (for drone to fly through) and buildings that have basements below the ground. It is very nice. But if we want to navigate it, we will soon discover that Nav2 package of ROS2 is not entirely up to the task. It uses flat world model.
Not just that, the more advanced your robot becomes, the less convenient it is to use 3rd party package you have no control over. This is why any large company I know about uses its in-house navigation tools. Can we do the same?
In this section I am going to create a simple yet flexible foundation, while in later sections I will add things, like landmarks based navigation and potentially, using AI.
But so far, I am going to simply duplicate part of Nav2 functionality here, with open source code and detailed explainations.