This ReadMe explains the concept, that was developed within the "Robotic and Computational Intelligence" project seminar at Technische Universität Darmstadt (Germany). A dynamic environment allows the training and usage of several network models for end2end control of the Frauenhofer IAIS Volksbot RT6 that was equiped with a Stereolabs ZED camera for computer vision.
Detailed information can be found here:
Follow the steps below to setup a similar environment that we used during the development phase. If you want to use the autonomous_driving package for a different robot you can skip all steps related to the volksbot-driver and replace it with !
As operating system Ubuntu 16.04.4 LTS (Xenial Xerus) with ROS Kinetic Kame is used since it is stated as prerequisite for zed-ros-wrapper (source) by Stereolabs. Besides this, the Ubuntu and ROS versions are in general very well supported and compatible to most software packages.
-
For the installation of ROS Kinetic Kame on Ubuntu Xenial Xerus follow the official instruction:
-
After that, create a new ROS workspace with
catkin_makeas shown in the following tutorial:https://wiki.ros.org/ROS/Tutorials/InstallingandConfiguringROSEnvironment
Clone our workspace into the newly created workspace:
cd <path-to-your-workspace>/src
git clone https://github.com/robbyHuelsi/VolksbotLineDetection.git ./autonomous_driving
In addition to our package you might need one package for retrieving images from a camera (i.e. in our case the Stereolabs ZED camera). If you also have the Stereolabs ZED camera, make sure that the ZED SDK, CUDA and Point Cloud Library are installed before you clone the following repository (source):
cd <path-to-your-workspace>/src
git clone https://github.com/stereolabs/zed-ros-wrapper
To control the robot (i.e. in our case the Volksbot RT6) a driver might also be necessary to install. The volksbot driver for example receives velocity commands formated as geomentry_msgs/Twist and sets the wheel speed according to its linear.x and angular.z floating point velocities (more on this later).
sudo add-apt-repository ppa:kbs/kbs
sudo apt-get update
sudo apt-get install libepos2-dev
cd <path-to-your-workspace>/src
git clone -b kinetic https://github.com/uos/volksbot_driver
If you want to record your own training data by controlling the robot via joystick and recording images and control commands at the same time you have to install the following ros packages in addition:
sudo apt-get install ros-kinetic-joy
sudo apt-get install ros-kinetic-teleop-twist-joy
In launch/logitech.config.yaml Logitech's Wireless Gamepad F710 is configures to controll the robot for recordings. For record training data its helpful to use a continuous linaer speed. Therefore yaml file is codificated to:
axis_linear: 5 # RT = right shoulder axis of gamepad
# old/default value of axis_linear: 4 # right directional pad up-down-axis of gamepad
scale_linear: -0.2 # max. linear speed for LB button pressed
scale_linear_turbo: -0.8 # max. linear speed for RB button pressed
axis_angular: 3 # right directional pad left-right-axis of gamepad
scale_angular: 0.5 # max. angular speed
enable_button: 4 # LB = left shoulder button of gamepad
enable_turbo_button: 5 # RB = right shoulder button of gamepad
Getting continuous linaer speed works by a small hack: The value of an untouched (right) shoulder axis of the gamepad is 1.0. Is it completely pressed in the value is -1.0. (0.0 is in the middle.)
If you want to start recording your own training data run roslaunch autonomous_driving joy_volksbot.launch and you are able to controll the volksbot. For that you have to press and hold all the time LB for normal linear speed or RB for turbo linear speed.
Problem: The gamepad's right shoulder axis (RT) is not sending 1.0 for linear speed from the start. To fix that just press RT a little bit and release. Now, if you press LB or RB the volksbot is moving forward with continuous speed. For moving backwards press RT completely in (while holding LB or RB). You can modify linear speed while driving by pressing RT more or less.