README with instructions for occupancy grid (#51)

* README with instructions for occupancy grid

* fix pip version

* moved readmelidar to root

---------

Co-authored-by: Si Un Kim <“Anniesiun@gmail.com”>

Dockerfile

@@ -16,7 +16,7 @@ RUN apt-get update --fix-missing
 RUN apt-get install -y vim
 
 # Install pip (updating is important!)
-RUN apt-get install -y python3-pip=22.0.2+dfsg-1ubuntu0.4 && pip3 install --upgrade pip
+RUN apt-get install -y python3-pip && pip3 install --upgrade pip
 
 # Setup ROSboard
 RUN apt-get install -y \

READMELIDAR.md

@@ -0,0 +1,98 @@
+# LiDAR-Based Occupancy Grid Generation
+
+This guide provides instructions for generating a live occupancy grid from our LiDAR data (Unitree L1) and creating an occupancy grid from recorded LiDAR data using ROS.
+
+## Prerequisites
+Make sure to have a ROS workspace set up and the necessary packages installed:
+- `unitree_lidar_ros` (for handling LiDAR data)
+- `pointcloud_to_grid` (for converting point clouds to an occupancy grid)
+
+## Part 1: Creating a Live Occupancy Grid from LiDAR
+
+### Steps
+
+1. **Terminal 1** - Initialize the ROS core and build workspace:
+    ```bash
+    cd ~/catkin_ws
+    catkin build pointcloud_to_grid
+    source devel/setup.bash
+    roscore
+    ```
+
+2. **Terminal 2** - Launch the LiDAR node:
+    ```bash
+    cd ~/catkin_ws/src/unilidar_sdk/unitree_lidar_ros
+    catkin_make
+    source devel/setup.bash
+    roslaunch unitree_lidar_ros run.launch
+    ```
+
+3. **Terminal 3** - Launch the occupancy grid generation node:
+    ```bash
+    cd ~/catkin_ws
+    catkin build pointcloud_to_grid
+    source devel/setup.bash
+    roslaunch pointcloud_to_grid demo.launch
+    ```
+
+4. **Terminal 4** - Launch RViz to visualize the occupancy grid:
+    ```bash
+    cd ~/catkin_ws
+    catkin build pointcloud_to_grid
+    source devel/setup.bash
+    roslaunch pointcloud_to_grid rviz.launch
+    ```
+
+## Part 2: Generating Occupancy Grid from a Recorded Bag File
+
+### Recording a Bag File
+
+1. **Terminal 1** - Launch the LiDAR node to start recording:
+    ```bash
+    cd ~/catkin_ws/src/unilidar_sdk/unitree_lidar_ros
+    catkin_make
+    source devel/setup.bash
+    roslaunch unitree_lidar_ros run.launch
+    ```
+
+2. **Terminal 2** - Start recording LiDAR data:
+    ```bash
+    rosbag record -O {enter_name_here}.bag /cloud
+    ```
+    - **Note**: Press `Ctrl+C` to stop recording when desired. Once recorded, close both terminals.
+
+### Playing Back the Bag File and Generating Occupancy Grid
+
+1. **Terminal 1** - Initialize the ROS core:
+    ```bash
+    cd ~/catkin_ws
+    catkin build pointcloud_to_grid
+    source devel/setup.bash
+    roscore
+    ```
+
+2. **Terminal 2** - Play back the recorded bag file:
+    ```bash
+    cd ~/catkin_ws
+    catkin build pointcloud_to_grid
+    source devel/setup.bash
+    rosbag play -l {enter_name_of_bag_file_here}.bag
+    ```
+
+3. **Terminal 3** - Launch the occupancy grid generation node:
+    ```bash
+    cd ~/catkin_ws
+    catkin build pointcloud_to_grid
+    source devel/setup.bash
+    roslaunch pointcloud_to_grid demo.launch
+    ```
+
+4. **Terminal 4** - Launch RViz to visualize the occupancy grid:
+    ```bash
+    cd ~/catkin_ws
+    catkin build pointcloud_to_grid
+    source devel/setup.bash
+    roslaunch pointcloud_to_grid rviz.launch
+    ```
+
+