/TurtleSim-Sketch

Primary LanguagePython

Project: Turtle-Sketch

Overview

  • In this project, the image on the left is taken as input and the image on the right is obtained as output by using turtlesim

Output

  • The image on the left can be selected using it's path as well as can be directly taken from the camera

  • The below videos show the project in action

    Click on the below animations for full video

Using an image

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Using webcam

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Concepts Used

Following are the concepts used for this project:

  • Dynamic reconfigure
    • To import the image using path
    • To import the image using camera
    • To set thresholds for Canny edge detection
  • ROS parameters
    • To set the values of threshold parameters
    • To fetch the values of threshold parameters
  • ROS services
    • To spawn the turtles
    • To teleport the turtle
    • To set the status of a pen as - ON/OFF
    • To remove the turtles after sketch is completed
  • OpenCV
    • To import image
    • To find the edges using Canny edge detection
    • To find the contours
  • Multi-processing
    • To spawn an army of turtles to draw the sketch

Directory Structure

  • The directory contains 3 packages:

    • sketch
    • dynamic reconfigure
    • image_thresholding

  • Sketch directory structure

    ├── CMakeLists.txt
├── docs                                 # Supported files for documentation
│   ├── Contours.png
│   ├── done.png
│   ├── dynamic reconfigure.png
│   ├── edges.png
│   ├── Output.png
│   ├── rosgraph.png
│   ├── test.png
│   └── turtles.png
├── include
│   └── sketch
├── launch                                # Launch Files
│   └── sketcher.launch
├── package.xml
├── README.md
├── nodes                                 # ROS Nodes
│   ├── ironman.jpeg
│   ├── sketcher.py
│   └── Turtle.py
└── TODO.md                               # TO DO for next version

  • Image_thresholding directory structure

    .
├── cfg                                    # Configuration file for GUI
│   ├── import.cfg                         # GUI params related to image import
│   └── thresholds.cfg                     # GUI params related to image thresholding
├── CMakeLists.txt
├── include
│   └── dynamic_parameters
├── launch                                 # Launch files 
│   └── canny_thresholding.launch            # Launch - GUI for Canny edge detection
├── nodes                                  # ROS Nodes
│   ├── get_values.py
│   ├── import_server.py                   # Import Image import parameters in python node
│   └── server.py                          # Import thresholding parameters in python node
└── package.xml

Coding Style Guide - PEP8

Dependencies

  • dynamic reconfigure package
  • OpenCV

Setup and Run

To run the project on your local system, follow the procedure:

  • Download the packages - sketch, image_thresholding, and dynamic-reconfigure-noetic-devel

  • Copy these packages to your ROS workspace i.e. ~/ROS_ws/src/

  • Build the workspace

    • $ cd ~/ROS_ws/
    • $ catkin_make

  • Open new terminal and source the ROS workspace - source ~/ROS_ws/devel/setup.bash

  • Run the command - $ roslaunch sketch sketcher.launch

  • This command will open turtlesim and GUI for this project

  • You can select image Address (0) or Camera (1) option for CaptureType

  • If you select Address (0), insert the path of the image on you system in the img_path section

  • Then click on the checkbox in front of Capture

  • If you select Camera (0), camera window will pop-up and you can click on the checkbox in front of Capture once you get the desired frame

  • This will open up a window with edges in the selected frame

  • Now, use the GUI to set minimum and maximum threshold values to get the desired contours

  • Click on the checkbox in front of Start to spawn an army of turtles which will sketch these contours for you

  • After the sketch is completed, the turtles will disappear

Note:

  • If you want to change the approach to sequential from parallel, follow the steps:
    1. Open launch file in this directory ~/ROS_ws/sketch/launch/
    2. The arg tag for the sketcher node has a value of 1
    3. Change this value to 0
  • Here, 0 = sequential execution and 1 = parallel execution

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