/eurobot2020_ws

Brainstorm Team Codebase for Eurobot 2020 competition

Primary LanguageMakefileMIT LicenseMIT

Brainstorm Robotics Logo

EUROBOT 2020 WORKSPACE

Repository exclusively for team Brainstorm - Middlesex University of London

All rights reserved © 2020, London, UK

GETTING STARTED

These instructions will get you a copy of the Eurobot project up and running on your local machine for development and testing purposes. See ROS Documentation section for notes on how to deploy and run the project on a Linux.

Prerequisites

What things you need to install the software and how to install them

First check DATE & TIME on Odroid

  • to check system date use date
  • to check hardware date use sudo hwclock

Don't commit any changes to github repo if the date n time is not set correctly

Versioning

For the versions available, see the tags of this repository and selected branches according to your role in the team. Keep code clean and leave comments in code or/and write brief documentation after each new feature deployed.

SYSTEM REQUIREMENTS

  • ROS Kinetic ONLY supports Ubuntu 16.04
  • Ubuntu MATE ISO image to download for ODROID
  • Open SSH - to establish remote connection
  • GIT - for version control
  • .bashrc file must be edited beforehand in order to run ROS locally on your PC (see section 'ROS: Installation' )

ROS DOCUMENTATION:

Getting started with ROS [Robot Operating System]

Installation

Edit bashrc in order to run ROSCORE

Environment setup

  • ROS environment variables are automatically added to your bash session every time a new shell is launched
echo "source /opt/ros/kinetic/setup.bash" >> ~/.bashrc
source ~/.bashrc

  • If you have more than one ROS distribution installed, ~/.bashrc must only source the setup.bash for the version you are currently using.

  • If you just want to change the environment of your current shell, instead of the above you can type:

source /opt/ros/kinetic/setup.bash

Usage

You must have a roscore running in order for ROS nodes to communicate. It is launched using the roscore command.

roscore
  • Run ROS in separate terminal and let it be running in the background
  • It can be only one instance of ROS running on machine
  • To terminate or close safely roscore, in the active terminal type:

CTRL + C

References, knowledgebase

ROS PACKAGES

Usage

Provides package list and info

rospackage list
rospackage name_pkg info

Run this to provide dependecies to any script. Minimal.launch provides basic robot functions essential to run any script in order of testing and development 

roslaunch pckg_name launch_file_name 
roslaunch eurobot_bringup minimal.launch

PACKAGE Upstart for ROS Robots

This package aims to assist with creating simple platform-specific jobs to start your robot’s ROS launch files as a service when its PC/ROBOT powers up.

Installation

sudo apt-get install ros-kinetic-robot-upstart
  • install YOUR launch file [within the src folder]
#rosrun robot_upstart install eurobot_bringup/launch/minimal.launch rosrun robot_upstart install eurobot_bringup/launch/minimal.launch --job eurobot_bringup --user root --rosdistro kinetic --logdir eurobot_bringup/logs
  • to complete the installation
sudo systemctl daemon-reload && sudo systemctl start eurobot
  • to view output to terminal
sudo tail /var/log/upstart/eurobot.log -n 30

Usage

  • The basic usage is with the install script, which can be as simple as:
rosrun robot_upstart install eurobot_bringup/launch/base.launch

This will create a job called eurobot on your machine, which launches base.launch. It will start automatically when you next start your machine.

  • You can bring it up, down and restart manually:
sudo service eurobot_bringup start
sudo service eurobot_bringup stop
sudo service eurobot_bringup restart
  • restarting service using bash alias (if created)
sudo ./restart_eurobot_service.sh

PACKAGE Turtle Bot for driving using controls

Provides teleoperation using joysticks or keyboard.

Installation

Usage

roslaunch turtlebot_teleop keyboard_teleop.launch

PACKAGE eurobot_bringup

PACKAGE navigation

PACKAGE robot_description

PACKAGE robot_drivers

PACKAGE robot_grippers

PACKAGE robot_vision

PACKAGE sensor_drivers

PACKAGE web_server

PACKAGE world_description

ROS NODES

Usage

Provides list and info of nodes

rosnode list
rosnode node_name info

NODE /drive_train_controller - driving systems, braking systems, odometry

NODE /range_sensors_ros_handler_node - ultrasonic sensors

NODE /robot_state_publisher - publishes robot states - ex for rviz

NODE /serial_com_data_handler - Serial port connections

NODE /web_server_node - Flask

ROS TOPICS

Usage

List of supported topic commands: (ordered by importance)

rostopic list   print information about active topics
rostopic info <topic-name>  print information about active topic
rostopic echo /topic_name  or /my_topic/field_name   print messages to screen
rostopic pub /topic_name std_msgs/String hello   publish data to topic
rostopic type /topic_name  print topic type
rostopic hz /topic_name    display publishing rate of topic

ROS FILES

FILE robot_drivers/script/robot_interface.py

Class required to minimal run contain all necessary APIs for grippers, experiment, update_robot_score, wait_for_pull_to_start, reset_odometry

need to be initiate

FILE robot_drivers/script/robot_interface_advanced.py

Class with inherited methods from robot_interface.py, contains all methods need for driving to the point, waypoints, get_distance, move_linear, move_angular, move_to,

need to be initiate

FILE robot_drivers/script/eurobot_task.py

Import all robot_interface_advanced.py methods and is the main file with driving commands for a small robot

Usage

Commands available in eurobot_task.py :

robot.update_robot_score(40.0)
robot.open_gripper()
robot.close_gripper()
robot.stop_motors()

LAUNCH Files:

Provide convenient way to start up multiple nodes and a master, as well as other initialization requirements such as setting parameters.

Usage

eurobot_bringup/launch/Eurobot_final.launch
  • other launch files running packages/nodes individually or partially
-> minimal.launch
-> nodepkg=”robot_drivers”
-> nodepkg=”robot_state_publisher”
-> sensors.launch
-> web_server.launch
-> eurobot_task.launch 
-> eurobot_task.py

Network configuration:

Robot scripts:

ROBOT DRIVERS:

Low level code in C++, not need to be changed at all. After every change in code needs to be recompiled by catkin_make

FOLDER "Includes"

FILE drive_train_manager.h

Class DriveTrainManager defines methods related with driving include headers from robot_params.h

set_motion()
reset_encoders()
reset_values()
stop()
set_velocity()
update_odometry()
current_x
current_y
  • defines EPOS objects assigned to the wheels, includes headers from epos_drive_manager.h
 // epos objects
EposDriveManager left_wheel;
EposDriveManager right_wheel;

FILE epos_drive_manager.h

Class EposDriveManager methods and definitions

initialize(const std::string device_name, const std::string port_name);
terminate() 
reset() 
set_rpm(const int motor_rpm) 
increment_position(const long delta_position) 
get_rpm(int &motor_rpm) 
get_position(int &motor_position) 
reset_encoders() 
stop() // apply brakes to the wheels

// return true if encoder is ineserted .set_inverted when creating object EPOS method
set_inverted();
reset_inverted();

FILE robot_params.h

Constance definitions of key paramiters for driving

// using meters, radians, etc. meteric only!
_RB_BASE_WIDTH 0.1714 // to contact center of wheels need to be changed as well
_RB_WHEEL_DIAMETER 0.07
_RB_NUM_OF_ENCODER_COUNTS 16384 // 4096 * 4 // old value
_RB_ABS_GEAR_RATIO (4554.0 / 130.0) // need to be chaged to 1
_RB_INVERT_RIGHT true // find out does it need to be changed or not

FILE drive_train_ros_handler.h

  • Includes (imports) all nessesery libraries and header files and the Thread. Contains ROS C++ library

FOLDER "Src"

FILE robot_interface.py

Basic driving methods

FILE robot_interface_advanced.py

Extension for Class robot_interface with more advanced driving methods

FOLDER "Script"

FILE epos_drive_manager.cpp - EposDriveManager() object

  • contains entire logic of methods defined in epos_drive_manager.h, manages EPOS devices and calculates PIDs

FILE drive_train_ros_handler.cpp

  • it uses callbacks listaning on topics for subcribers
  • Set the publish rate for Publishers, change according to performance (now it's 10)
int publish_rate;
	nh.param<int>("publish_rate", publish_rate, 10)
  • creates the ROS Subscribers:
/cmd_vel
/cmd_vel_mux/input/teleop
/reset_drive_train
/initialpose
/update_drive_train_position
  • creates the ROS Publisher
/odom
  • runs the odometry thread which publish data in while loop to /odom
thread odometry_update_loop(odometry_loop)

FILE drive_train_manager.cpp

  • DriveTrainManager instantiation with assigning EPOS devices to "USB0" and "USB1" port
  • Creation and functionality of wheel objects
left_wheel  = EposDriveManager();
right_wheel = EposDriveManager();
  • _RB_INVERT_RIGHT - inverssion of the wheel according to robot build
  • DriveTrainManager::update_odometry() - calculations of driving odometry

Electronic parts list:

FAQ

  • In case of Arduino crash - restart the service
  • After creating python script make it executable with command: chmod +x script.py
  • I can't compile with catkin_make: ⋅⋅⋅ If you want to compile something you need to update the clock (time) ⋅⋅⋅ You must navigate to main workspace directory while you run the command
  • roscore is not running, ROS can't locate ROS_MASTER ip adress ⋅⋅⋅ edit bashrc.sh and modify lines: export ROS_HOSTNAME=127.0.0.1 export ROS_MASTER_URI=http://127.0.0.1:11311
  • Roscore is running wrong workspace ⋅⋅⋅ to check current workspace type echo $ROS_PACKAGE_PATH ⋅⋅⋅ add workspace patch to bashrc.sh file source /home/ros/your_workspace/devel/setup.bash

Contributors:

Sponsors:

  • FESTO
  • Maxon Motors
  • Rapid Electronics
  • PozyX

License

This project is licensed under the MIT License - see the LICENSE file for details

Acknowledgments

  • Hat tip to anyone whose code was used
  • Inspiration
  • etc

Our Credo: Show up, Deliver, Be Kind, Repeat