Installation

Note that this is dependant on all dependencies noted below.

cd ~/catkin_ws/src/
git clone https://github.com/selyard/elyard_walker.git
cd ~/catkin_ws && catkin_make

Dependencies

This was developed using ROS Melodic and Gazebo. I was unable to install the Turtlebot simulator using the in-slide instructions. I found alternate installation instructions on this site, but they may produce a slightly different result than originally intended.

cd ~/catkin_ws/src/
git clone https://github.com/ROBOTIS-GIT/turtlebot3_simulations.git
cd ~/catkin_ws && catkin_make

Usage

To Run Using Launch File

Parts of the code for this launch file was copied from the "turtlebot3_gazebo turtlebot3_world.launch" file included in the Turtlebot3 Simulation git source. It was modified to decrease the time before the rover encountered an obstacle.

This code could conceivably work in any Gazebo world; however, it was only tested on this specified world. This world contains an outside barrier preventing the robot from traveling into infinity, as well as a series of pillars which serve as obstacles to avoid.

roslaunch elyard_walker walker_demo.launch

There are several argument options for the launch file:

• Walker Algorithm:
  • freq:=(integer) defines a frequency of output messages; defaults to 30hz
  • rec:=true records a 30-second ROSbag; defaults to false. Recording is saved in ~/.ros/ directory.
  • avoid_angles:=(integer) define a number of rangefinder sensor intervals to avoid for collision avoidance - for the burger model, 1 interval is roughly 1 degree. This is plus/minus value from center. Defaults to 10.
  • min_dist:=(double) defines how close the robot can get to an obstacle before turning to avoid; defaults to 0.75.
• Gazebo Parameters
  • model:=(string) defines the rover model; defaults to "burger".
  • x_pos:=(double) defines the starting X position; defaults to (-2.0)
  • y_pos:=(double) defines the starting Y position; defaults to (0.0)
  • z_pos:=(double) defines the starting Z position; defaults to (0.0)

Working with Recorded Bag File

The recorded bag file is stored in thedefault ~/.ros/ directory. To inspect the pre-recorded bagfile provided, starting from the install directory

cd results
rosbag info output_bag.bag

To play back the recorded bagfile, ROScore needs to be running as well.

roscore

Once this is running, from the install directory:

cd results
rosbag play output_bag.bag

To Run Sections Individually

To run Gazebo:

export TURTLEBOT3_MODEL=burger
roslaunch turtlebot3_gazebo turtlebot3_world.launch

To tele-operate: in a separate terminal, run:

export TURTLEBOT3_MODEL=burger
roslaunch turtlebot3_teleop turtlebot3_teleop_key.launch

To run the walker script instead, in a separate terminal, run:

rosrun elyard_walker walker_script

Other Notes

Deliverables

Deliverables are included in the Results folder.

CPPCheck + CPPLint

CPPCheck and CPPLint checked and passed. To run the scripts, navigate to the install directory and run:

chmod +x check_cppcheck.sh check_cpplint.sh
./check_cppcheck.sh
./check_cpplint.sh