Ohmni Robot TDT-ROBO Team

ohmni-ros-gui

The required packages to build the control GUI for Ohmnibot

These packages alow us to perfrom certain tasks on OHmnibot:

Prequisite setting:

Clone the ohmni_amcl inside the local machine and build with catkin_make

#mounting a directory inside the Ohmnibot ROS docker environment

In bot cli> docker run -it --network host --privileged -v /data/data/com.ohmnilabs.telebot_rtc/files:/app -v /dev:/dev -e ROS_IP=[bot_ip] [tb_control_docker_image]

Create the ohmni_ws directory to contain the developing source code.

Clone rplidar_ros and ohmni_gui_bridge packages inside the ohmni_ws/src directory and run catkin_make to build the packages

Note:

The Lidar port might changes when we restart the bot so follow this step to redirect the port:

Ohmni_ws> cd src/rplidar_ros/launch

Use Vim to edit the file rplidar.launch - Change the serial port value accordingly (Usually /dev/ttyUSB0 or /dev/ttyUSB1)

1. Use RPLidar to map the working environment and perform SLAM on Ohmnibot.

Set up the environment.

In bot ohmni_ws> source devel/setup.bash
In bot ohmni_ws> roslaunch rplidar_ros rplidar.launch

In local machine> export ROS_IP=[local_machine_ip]
In local machine> export ROS_MASTER_URI=http://[bot_ip]:11311

Mapping the work environment

In local machine> rviz # Open rviz and change the fixed frame into map,

#Use rqt_robot_steering to manually control the bot around the place. 
In local machine> rosrun rqt_robot_steering rqt_robot_steering

#Run Ros gmapping.
In local machine> rosrun gmapping slam_gmapping scan:=/scan
In local machine> rosrun map_server map_saver -f ~/map #After completed mapping

• Note: the map.pgm and map.yaml should be save to the maps folder inside the package.

Perform simple localization using ROS amcl

In local machine> roslaunch ohmni_amcl ohmni_amcl.launch

2. Building a web API to connect the Ohmni's ROS topics with other webAPIs by using Rosbridge.

Set up the environment.

# Run webserver for the GUI using rosbridge.
In bot ohmni_ws> roslaunch ohmni_gui_bridge websocket.launch

# Navigate to the directory with the .html file and run  a Python http server
In bot ohmni_ws> cd src/ohmni_gui_bridge/gui
In bot ohmni_ws> python -m SimpleHTTPServer

Afterwards you should be able to go to http://localhost:8000/ and you should see a directory listing containing the gui.html file. Click on it and it should open your website on the Ohmni touch screen web browser.

3. Publish Measured data to server via MQTT protocol.

Set up the environment.

1. We use ESP32 module to collect external data (SpO2 sensor, temperature sensor, ...)
2. Server HiveMQ: http://www.hivemq.com/demos/websocket-client/

Run ESP32_Hive_MQ.ino file.

Note: For convenience, we simulate the measured values from the sensor using the included real-time matching random function.

• Replace your SSID, password to connect HiveMQ server.
• Data will be retrieved from hiveMQ server and displayed on screen Ohmni Robot

4. QR code reading.

The required packages to build the read QR-code using python for Ohmnibot

These packages alow us to perfrom certain tasks on OHmnibot:

install library

pip install imutils pip install qrcode pip install pyautogui pip install numpy pip install opencv-python pip install opencv-contrib-python pip install pyzbar

How code work

using pyautogui library for take screenshot

use: pyautogui.screenshot("screenshot.png")

This code help take the screenshot and create image "screenshot.png"

using opencv2 library for reading image from screenshot

use: img = cv2.imread("screenshot.png") This code use opencv2 to open the image "screenshot.png"

use: cv2.imshow('Result', imutils.resize(img, width=600)) This code show the result qr code data.

using qrcode library for reading QR code image

use: for barcode in decode(img): myData = barcode.data.decode('utf-8') print(myData) pts = np.array([barcode.polygon], np.int32) pts = pts.reshape((-1, 1, 2)) cv2.polylines(img, [pts], True, (255, 0, 255), 5) pts2 = barcode.rect cv2.putText(img, myData, (pts2[0], pts2[1]), cv2.FONT_HERSHEY_SIMPLEX, 0.9, (255, 0, 255), 2) This code can transform qrcode image from "screenshot.png" to myData and show data.

using os library for remove file "screenshot.png"

use: path = 'screenshot.png' os.remove(path) This code can remove file "screenshot.png" when finished reading QRcode

Run code

python robot_qr_tdt.py