The main purpose of app code is to facilitate path creation and motion planning for a turtlebot 2 following the turtlebot 2s motion model. Then using the generated path/motion commands, easily send them to a Turtlebot2 using ROS.
Waypoint Control: Module that controls adding, removing, saving, and loading waypoints. Most functions require at least 3 waypoints to be added to the map. Waypoints are entered by adding x,y coordinates (Note that the robot assumes its starting potison is x=0, y=0, theta=0)
Generate Path: Once the waypoints are added, the generate path button can be used to create a series of commands to follow the waypoint path as genereated by a purepursuit controller and motion model.
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The purepursuit controller generates linear and angular velocity commands which are applied for command interval seconds to a 'simulated' turtelbot via a motion model. The new position is then fed to the purepursuit controller until a path is generated that reaches all waypoints.
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Finally the predicted path is plotted.
Saving Commands: Once a path has been genereated, the commands used to follow that path can be saved.
ROS Connect: To apply the motion commands to a live Turtlebot you must be connected to a ROS network with the Turtlebot, enter the IP of this connection here.
ROS Publish Control: This module publishes motion commands over a ros network to the /mobile_base/velocity_commands topic to move the turtlebot along the generated path. Commands and waypoints MUST be loaded to start this.
Toggle Live PP: Check box determines if pure pursuit should be done 'live' using [x,y,theta] values obtained from /odom topic. If checked, then any pre-generated paths/commands will be ignored.
Toggle Live Plot: This check box control whether plotting will occur while commands are being sent over ros. The plot will show the predicted Turtlebot moving along the path. NOTE THAT PLOTTING CONSUMES COMPUTATION RESOURCES AND MAY AFFECT PERFORMANCE
Toggle Plot Odom: This check box allows for values saved from the /odom topic to be plotted while following a pre-generated path. If using live pure-pursuit this check box will have no effect as the predicted and odom values will be the same.