Turtle Trajectories and Xacro ARM

Table of Contents

• Overview
• Getting Started
• Usage and Configuration Instructions

Overview

This repo contains 2 independent projects:

Part 1:

This package contains files that control the turtlebot's speed and direction, and make it move in an eight-shape trajectory.

1. The turtlebot begins in a paused state and believe that that configuration is (x, y, z) = (0, 0, 0), relative to it's odometry frame.
2. Upon calling the resume service, the turtlebot will enter a "moving" state and begin following the eight-shape trajectory.
3. Upon calling the pause service, the turtlebot will pause its motion, without resetting its position.

Part 2:

In this part I created a Xacro URDF for the robot arm shown below, visualized it in rviz, and made it's end-effector follow a trajectory.

Getting Started

Create a workspace, clone the repo, and build the workspace:

mkdir -p ws/src && cd ws/src
git clone https://github.com/YaelBenShalom/Turtle-Trajectories-and-Xacro-ARM.git
cd ../..
catkin_make
source devel/setup.bash 

Usage and Configuration Instructions

Part 1:

1. To activate the turtle, SSH into the turtlebot (ssh ubuntu@turtlebot.local) and run roslaunch turtlebot3_bringup turtlebot3_robot.launch.

2. To start running the turtlebot in figure-eight trajectory, run roslaunch Turtle-Trajectories-and-Xacro-ARM figure_eight.launch. The turtle begins in a paused state.
   

   

   1. To launch the rqt_plot and show the turtlebot's x and y position (from odometry) vs. time, add rqt_plot:=True to the roslaunch command.

   

   2. To launch the turtlebot Gazebo simulation, add Gazebo:=True to the roslaunch command.

   

   3. To launch the turtlebot Gazebo simulation, add rviz:=True to the roslaunch command.

   

3. To move the turtle, call the service resume (rosservice call /resume).

4. To pause the turtle movement, call the service pause (rosservice call /pause).

5. To change the parameters width (W - the width of the figure eight), height (H - the height of the figure eight), period (T - the period of time it takes the turtlebot to complete the figure eight), edit the file config/trajectory.yaml

6. To change the parameter pub_freq (R - the frequency at which we publish the cmd_vel messages) edit the file launch/figure_eight.launch.

7. To test the calculated values at t=0 and at t=T/2 (half a cycle), run catkin_make run_tests from the root of workspace.

8. To see the transformation between the world frame and the odom frame, run rosrun tf tf_echo /world /odom

9. To watch the rqt tree, run rosrun rqt_tf_tree rqt_tf_tree

Part 2:

1. To run the arm launchfile on rviz, run roslaunch Turtle-Trajectories-and-Xacro-ARM xacro_arm.launch.
2. To run the launchfile on rviz with gui, run roslaunch Turtle-Trajectories-and-Xacro-ARM xacro_arm.launch gui:=True
3. To run the arm launchfile on rviz with the marker, run roslaunch Turtle-Trajectories-and-Xacro-ARM mark_arm.launch