The gazebo simulation of the MANI rover. The simulated rover can be controlled via the respective ROS topics. It can also be controlled via a joint stick if used in conjunction with the MANIros package.
This package requires familiarity with ROS and Gazebo. Please also check whether your graphic card is compatible with Gazebo.
- Overview
- Getting Started
- Spawning MANI in a (custom) world
- Gazebo Integration
- ROS Integration (Robotic Operating System)
- Built With
- Authors, License, Acknowledgements
This package simulates the MANI rover in Gazebo. Gazebo is a 3D open-source robotics simulator. To control the simulated rover, you can use ROS. ROS, or Robotic Operating System, is "an open-source, meta-operating system for your robot. It provides the services you would expect from an operating system (...). It also provides tools and libraries for obtaining, building, writing, and running code across multiple computers." (ROS Introduction, http://wiki.ros.org/ROS/Introduction, Aug 16th 2019). To move the simulated rover (e.g. to move its wheels / steering angles / camera head), you can publish to so-called ROS topics (see section "ROS Overview"). The Gazebo simulator will then take the published information from ROS and move the simulated rover accordingly. The simulated rover's camera also publishes to the respective ROS topics, and you can get the camera's output by subscribing to these ROS topics (see section "MANI camera").
The following sections will guide you through the installation of the MANIsimulation package and its dependencies.
- Install
ROS kinetic: http://wiki.ros.org/kinetic/Installation
The MANIsimulation package requires ROS Kinetic Kame. Desktop-Full install is recommended for this package.
- If you didn't install Gazebo in step 1 (Gazebo7 is included in the ROS Kinetic Kame Desktop-Full install), install
Gazebonow. You can test whether Gazebo is properly installed by typing$ gazebo. An empty gazebo world should be launched.
$ curl -sSL http://get.gazebosim.org | sh
- Install
ros_control:
$ sudo apt-get install ros-kinetic-ros-control ros-kinetic-ros-controllers
- Install
gazebo_ros_pkgs:
$ sudo apt-get install ros-kinetic-gazebo-ros-pkgs ros-kinetic-gazebo-ros-control
-
Install Catkin and set up a Catkin Workspace:
- install catkin
$ sudo apt-get install ros-kinetic-catkin- create and build a catkin workspace
$ source /opt/ros/kinetic/setup.bash $ mkdir -p ~/catkin_ws/src $ cd ~/catkin_ws/ $ catkin_make- source your new setup.*sh file:
$ source devel/setup.bash
If you are not very familiar with catkin and/or would not be able to explain the steps taken above: http://wiki.ros.org/catkin/Tutorials
It is assumed that you have installed catkin and sourced your environment. It is also assumed that you already have a catkin workspace called catkin_ws.
- Clone MANIsimulation into your catkin workspace.
$ cd ~/catkin_ws/src
$ git clone https://github.com/PTScientists/MANIsimulation.git
- Build your catkin workspace.
$ cd ~/catkin_ws
$ catkin_make
- Launch the simulation.
$ roslaunch manisim gazebo.launch
You should see a MANI rover in an empty gazebo world. Have fun!
If you get an error, check whether your graphic card is compatible with Gazebo.
It is assumed that you have sourced your environment. It is also assumed that you have a catkin workspace called catkin_ws.
$ roslaunch manisim gazebo.launch
- Save a
.worldfile in~/catkin_ws/src/MANIsimulation/manisim_gazebo/worlds. The manisim package comes withempty.worldandmoon.world. - Launch MANIsimulation with the
worldcommand line argument. For example, if you want to launch MANI inmoon.world, type:
$ roslaunch manisim gazebo.launch world:=moon
A safe spawning spot on moon.world is (x,y,z) = (0, 20, 0).
Please be aware that when launching MANI in a custom world file, it needs to be spawned in a 'safe' spot to ensure functionality of the simulation. For example, if you were to launch MANI on a steep slope, MANI might start sliding and behave unpredictably right after being spawned. See the section below on how to set a spawning spot (position).
You can define the x-, y- and z-position MANI is spawned at when launching Gazebo. The default values are x=0, y=0 and z=0.2175. (If z was 0, MANI would be placed slightly in the ground of empty.world. This is due to the position of MANI's own origin.)
You can set each position coordinate individually. For example, to set x=5, type:
$ roslaunch manisim gazebo.launch x:=5
You can also set them all together. The order doesn't matter here:
$ roslaunch manisim gazebo.launch y:=3.2 x:=5 world:=empty z:=1
Gazebo is a 3D robotics simulator. It is open-source. You can find useful tutorials here. A good starting point for creating robot models in Gazebo is here.
Before using Gazebo, check out its system requirements here.
There is a typical error called BadDrawable which is due to incompatible graphic cards/drivers. Often, this error occurs only sometimes during launch, and otherwise Gazebo launches up fine. If you get this error, please check whether your drivers are installed properly. You can also try to launch the MANIsimulation with roslaunch multiple times to see if it eventually launches up successfully. Feel free to also check out this post and this post regarding this issue.
MANI consists of the following links:
- chassis
- camera_pan, camera_tilt, camera_kinect
- steering_angle_frontleft, steering_angle_rearleft, steering_angle_rearright, steering_angle_frontright
- wheel_frontleft, wheel_rearleft, wheel_rearright, wheel_frontright
chassis is the root link. The other links are all connected to the root/to each other via joints. The ROS Integration section describes how to control these joints via ros topics.
MANI's links and joints are labelled based on their positions in respect to the robot itself. The positions are as follows:
You can change MANI's inertia moments if needed. Open the file MANIsimulation/manisim_description/urdf/manisim.urdf.xacro and proceed as described here in section "Filling in the tags in URDF or SDF". manisim.urdf.xacro is a URDF based file.
Wikipedia's Definition July 24th 2019, 15:57 CET
Robot Operating System (ROS or ros) is robotics middleware (i.e. collection of software frameworks for robot software development). Although ROS is not an operating system, it provides services designed for a heterogeneous computer cluster such as hardware abstraction, low-level device control, implementation of commonly used functionality, message-passing between processes, and package management.
To get started with ROS, you can find useful tutorials here.
You can move MANI in Gazebo by publishing to the following ROS topics. They expect a std_msgs/Float64 message.
- Wheels (Velocity in m/s)
- front left:
/manisim/drive_fl_vel/command - rear left:
/manisim/drive_rl_vel/command - rear right:
/manisim/drive_rr_vel/command - front right:
/manisim/drive_fr_vel/command
- front left:
- Steering Angles (Orientation in rad)
- front left:
/manisim/steer_fl_ort/command - rear left:
/manisim/steer_rl_ort/command - rear right:
/manisim/steer_rr_ort/command - front right:
/manisim/steer_fr_ort/command
- front left:
- Camera Head (Orientation in rad)
- camera pan:
/manisim/camera_pan_ort/command - camera tilt:
/manisim/camera_tilt_ort/command
- camera pan:
If you want to know the current position, velocity or effort of any of MANI's joints, subscribe to the /manisim/joint_states topic. For information on the joint states ROS message, look here. You can read up on joint_state_publisher here.
The currently implemented depth camera for the MANI gazebo model is based on the kinect camera setup described in this tutorial. This tutorial also explains how to visualize the generated point cloud in Rviz.
MANI's camera publishes to the following topics:
- /camera/depth/camera_info
- /camera/depth/image_raw
- /camera/depth/image_raw/compressed
- /camera/depth/image_raw/compressed/parameter_descriptions
- /camera/depth/image_raw/compressed/parameter_updates
- /camera/depth/image_raw/compressedDepth
- /camera/depth/image_raw/compressedDepth/parameter_descriptions
- /camera/depth/image_raw/compressedDepth/parameter_updates
- /camera/depth/image_raw/theora
- /camera/depth/image_raw/theora/parameter_descriptions
- /camera/depth/image_raw/theora/parameter_updates
- /camera/depth/points
- /camera_ir/depth/camera_info
- /camera_ir/parameter_descriptions
- /camera_ir/parameter_updates
- Nathalie Hager - Initial work - Git Profile
See also the list of contributors who participated in this project.
At the time of writing this README, the license hasn't been decided upon yet. Please refer to the PTScientists Git Repo for more information.