This repo contains a custom ROS1 Noetic Workspace for Alex (CG2111A).

Look at this repo for TLS + Arduino Code.

Main functionalities include launching of rplidar-a1 node and hector-slam. Real-time map visualisation can be done using either RVIZ or Foxglove Studio (covered in this readme). Map saving can be done using ROS Map Server.

Setup & Teleoperation Demo

Physical	URDF

1. Clone Repo

git clone https://github.com/ShengBin-101/alex_ws.git

2. Init and Update Submodules (rplidar and hector_slam)

git submodule init
git submodule update

3. Build Workspace

catkin_make

4. Source built binaries

source devel/setup.bash

5. Run roscore or Start ROS master

roscore

6. Run lidar.launch from alex package to start lidar node

roslaunch alex lidar.launch

7. Run slam_laptop.launch file on laptop to run hector_slam node

This allows you to offload SLAM computation from the pi.

roslaunch alex slam_laptop.launch

Follow this guide for first time set up for lidar

sudo apt-get update

Install Dependencies

sudo apt-get install cmake python-catkin-pkg python-empy python-nose python-setuptools libgtest-dev python-rosinstall python-rosinstall-generator python-wstool build-essential git
sudo apt-get install qt4-qmake qt4-dev-tools

Change permissions for lidar's port

sudo chmod 666 /dev/ttyUSB0

Install Map server and create maps directory to hold maps.

sudo apt-get install ros-noetic-map-server
mkdir ~/alex_ws/maps

cd ~/alex_ws/maps
rosrun map_server map_saver -f <map_name>

On one terminal run

roscore

On another terminal

cd ~/alex_ws/maps
rosrun map_server map_server my_map.yaml

Map can be viewed on RVIZ

rviz

Map can also be viewed on foxglove. Look at below section for foxglove.

Foxglove allows you to visualize topics broadcasted by the Pi, provided you are connected to the same network. Make sure foxglove is installed on pi.

Download Foxglove Studio here

    sudo apt install ros-noetic-foxglove-bridge

Start foxglove websocket:

    roslaunch --screen foxglove_bridge foxglove_bridge.launch port:=8765

Open up foxglove application on your laptop (make sure you are in same network as pi)

TLS can be enabled, just need add path to certificates. More info here: https://github.com/foxglove/ros-foxglove-bridge

Scan of my room	Map of a random Seminar Room in my hostel :)

    roslaunch alex diff_drive.launch