Update README.md

Author: estherag

README.md

@@ -1,2 +1,38 @@
 # easynav_pointcloud_stack
 
+This stack is part of the Easy Navigation (EasyNav) project developed by the Intelligent Robotics Lab. It is composed of the **pointcloud_maps_builder** package and the **pointcloud_maps_manager** package (currently under construction).
+
+The `PointcloudMapsBuilderNode` subscribes to point cloud sensor data, downsamples and fuses it, and republishes the processed data for mapping or further processing.
+
+
+
+## Parameters
+
+| Parameter Name            | Type    | Default   | Description                                      |
+|--------------------------|---------|-----------|--------------------------------------------------|
+| `sensor_topic`           | string  | `points`  | Topic to subscribe for point cloud input         |
+| `downsample_resolution`  | double  | `1.0`     | Resolution to use when downsampling              |
+| `perception_default_frame` | string | `map`     | Target frame for fusing point clouds             |
+
+---
+
+## Installation
+
+Clone the repository into your ROS 2 workspace:
+```bash
+cd ~/ros2_ws/src
+git clone https://github.com/EasyNavigation/easynav_pointcloud_stack.git
+cd ..
+colcon build --packages-select easynav_pointcloud_maps_builder
+```
+
+## Usage
+
+Source your workspace:
+```bash
+source ~/ros2_ws/install/setup.bash
+```
+Run the lifecycle node:
+```bash
+ros2 run easynav_pointcloud_maps_builder pointcloud_maps_builder_node
+```