The goal of this 4-week project is to make a state of the art of the simulator available on the drone market and try out some solutions.
For this project, the Software In the Loop method must be priviledged as it "characterizes a numerical simulation of the operation of the software of an embedded system during which the entire environment, including the hardware part of the embedded system, is simulated." from wikidictionnary. The focus will be on ROS friendly simulators. Mostly using Melodic, as well as Kinetic if needed.
The previous project found solutions using ROS, Gazebo and :
- RotorS, in ROS Kinetic with various drones,
- BebopS, a fork of RotorS which works with Parrot 2 only and on Melodic,
- TUM simulator, only with A.R. Drone 2, on ROS Melodic,
- SJTU drone, fork of TUM Simulator on Melodic, Parrot ARDrone,
- ArduPilot and SITL simulator, no need of ROS nor Gazebo but compatible, very handy and widespread.
We have looked for the more widespread simulators that could be used along with ROS.
| Simulators | Gazebo | DJI Assistant | DJI flight simulator | jMAVsim | New Paparazzi Simulator |
|---|---|---|---|---|---|
| Type | Simulator 3D | Software with embedded simulator | Simulator 3D with flight controller and FDM | Simulator 3D of drones (not worlds) | Simulator 3D |
| ROS version | All | Kinetic (and Melodic with plugins) | Not compatible | Melodic | Under developpement |
| Works on Linux | Yes | DJI's simulation supports only Windows/Mac, need to add the dji_m100 package below on the OSDK to make it run on Linux | No only Windows 10 | Yes | Yes |
| Drones available | Multirotors (1 to 8) | All DJI | Many DJI | Quadrotors | Rotorcrafts |
| Sensors | Many (create and modify) | Many | Many | No incorporation of sensors | Depending on the vizualisation mode |
| Obstacles | Yes | None | Yes and avoidance | No | No |
| Physical impact on the drone | Yes (wind ...) | No | Yes (wind, crash, floor effect...) | Some (crash...) | |
| Worlds | Many and customisable | One | Many | Not made for this | |
| SITL | Yes | No | No | Yes | Yes |
| Compatibility | Many | Gazebo | Can use various UAV controller | Use MAVLink protocol, Java3D library, works with PX4, SITL simulator, interfaced to ROS | With all the Paparazzi suite and others tools |
| Multi-vehicle simulation | Yes but can only simulate a single type of vehicle at a time | No | No | Recommended if you need to support a lot of quadcopters, and the simulation only needs to be approximate | Possible but need some troubleshooting |
| Links | Official website | Link to download the assistant, only empty world available by itself | Official web site, free for some drone but need a dji account | With SITL, and more | Wiki |
| More | Most complete and used | Only for DJI, poor versatility | Mostly for training, need at least a DJI controller | Multi drone |
Added to the simulator, ROS packages are here to complete the simulation according to our needs.
| Package | dji_m100 suite | Hector quadrotor | SJTU | ROS Quadrotor Simulator | BebopS |
|---|---|---|---|---|---|
| Type | Package | Metapackage | Package | Package | Package, forked from RotorS |
| ROS version | Kinetic and Melodic | Kinetic and Melodic | Melodic | Indigo (maybe Kinetic) | Kinetic and Melodic |
| Simulator | Gazebo 7 or 8 | Gazebo 7 or more | Gazebo 7 | Gazebo 7 | Gazebo 7 or more |
| Cmake version | 2.8.3 or newer | 2.8.3 or newer | 3.2.2 | 2.8.3 | 2.3.8 |
| Drones | DJI M100 only | Generic quadrotor | Parrot AR Drone | AsTec and others multirotors | Parot Bebop 2 |
| Sensors | Camera, GPS, mission | Forward camera, laser, sonar, many more... | Forward/backward camera, laser, sonar, IMU | Camera, sonar | IMU, camera, laser 1D |
| Topics | uav1/... same as before | Odom, attitude, cmd_vel | Topics related to sensors or use RQT GUI | ||
| Navigation | Joysticks | Joysticks, can add keyboard | Joystick, keyboard or waypoints | Xbox joysticks, waypoints, autonomous | Waypoints in a text file |
| Worlds | Some (collision etc) | Complex, indoor and Outdoor | Some | Many, indoor and outdoor | Some, outside |
| Physical impact on the drone | None | Wind | Wind | Wind | Wind |
| GUI | Rviz or rqt_gui | Rviz | rqt_gui or GZcliebnt from Gazebo | Rviz | Rviz |
| Compatibility | Gazebo pluging and a modifiable URDF file, used with the OSDK | Generic modifiable quadrortor URDF file, interface with Gazebo, cannot support MAVLinks and hardware platforms like Pixhawk. Can be interfaced with MoveIt! | Many Gazebo plugins | Use mav comm package from PX4, MoveIt! and RotorS | Modifiable URDF files, |
| More | Need the drone. Collision free | Kinect, multiple plugins, demos, flight dynamics | Simulate a race. May need Gazebo 9 and Ubuntu 18.04. Fork of tum_simulator | Path planning, obstacle avoidance, ~2 and 3D mapping | Choose your own FDM backends |
| Links | See branch ROS_Kinetic_Gazebo | Package, tutorial, more explanations and possibilities | See previous work or here | See here | Tutorial |
If we want to use more advanced flight fonctionalities, flight controllers can also be used. They require a more complicated structure, with often several softwares that have to be interfaced together.
| Flight controller | PX4 | Ardupilot | Paparazzi |
|---|---|---|---|
| ROS version | Melodic | Melodic | Under developpement |
| Simulator | Gazebo, jMAVsim | SITL, Gazebo | Gazebo or its own simulator New Paparazzi Simulator using JSBSim (FDM) |
| Compatibility | Plugin Gazebo 9 | Plugin Gazebo, use SITLsimulator and MavProxy, however ROS with SITL in Gazebo is under creation | Gazebo, JBSim, FlightGear |
| Drones | Multirotors | Wide range, can use package ArduCopter, multirotors ready to use here | Multirotors (choice limited by hardware) |
| Multi-vehicle simulation | Possible with Gazebo, FlightGear and JMAVSim | Tools in development | Possible |
| Navigation | GPS (waypoints and position hold), stereo vision | GPS, mission planner, follow me and click on the simulation (with SITL) | GPS (waypoints and position hold), stereo vision |
| Communication | MAV Link | MAV Link or MAVRos (see note 2) | MAV Link |
| More | Flight stack and autopilot | DO not need ROS and Gazebo to work properly but compatible (see note 1), use Linux Ubuntu 18.04 | Automated take off and landing |
| Links | Official github | Wiki | Wiki |
Notes :
- "We will be using a standard version of ArduPilot but with a custom plugin for Gazebo, until the gazebo plugin gets merged into Gazebo-master. This plugin can be used with or without ROS integration."
- "MAVROS is a ROS “node” that can convert between ROS topics and MAVLink messages allowing ArduPilot vehicles to communicate with ROS."
- About SITL : SITL allows you to run ArduPilot on your PC directly, without any special hardware. It takes advantage of the fact that ArduPilot is a portable autopilot that can run on a very wide variety of platforms. When running in SITL the sensor data come from a flight dynamics model in a flight simulator. Is only in 2D but has many sensors : GPS, wind, barometer, avoidance, fence, vibrations...
| Name | OSDK for DJI | Paparazzi Project |
|---|---|---|
| Type | Development toolkit for developing applications, which could run on the onboard computer. Needs to be used with the DJI assistant. | UAV multiple software |
| ROS version | Kinetic, Cmake 2.8.3 or newer | Paparazzi Project |
| Simulator | Got is own with the DJI assistant, compatible with Gazebo 7 or more through dji_m100 package | NPS or Gazebo |
| Drones | All DJI | Rotorcrafts |
| Sensors | Camera, GPS, mission, IMU | Depending on the vizualisation mode |
| Navigation | With the assistant, use joysticks | |
| Physical impact on the drone | None | |
| GUI | From the assistant | |
| More | Need the drone, runs on Linux and ROS | |
| Links | Package |
Our project group found out that Gazebo was the best simulator to be used regarding its ROS compatibility, sensors emulated and modifiability/compatibility as it uses plugins to accept custom inputs, output custom data, and perform custom control in simulation. The former group project tried out :
- BebopsS, worked well but needed to change the waypoints directly onto the waypoints.txt
- SJTU_drone, no issues noted
- ArduPilot and SITL, the most advanced tutorial with the most capacities, but did not try with Gazebo.
Hence, we choose to test out 2 different solutions : continue with the Ardupilot with Gazebo and/or ROS, look at the possibilites given by the Hector Quadrotor metapackage. We will also be looking for informations about DJI assistant because the ALPAGA team already has a M600.
We tried out 3 solutions, working very differently from one to another :
- Hector quadrotor, which is a meta package,
- DJI assistant and flight simulator, a full suite of software to use with a DJI drone, unfortunatly we couldn't try it by ourselves,
- Ardupilot flight controller paired with Gazebo or ROS.
Hector had the advantage of being very user friendly : everthing comes with the package, no need to install many softwares and it is low level so pretty easy to modify.
DJI was very complete and accurate but would only work using the DJI hardware.
Ardupilot was the most complete but it was a bit hard to understand its architecture with ROS or Gazebo.
Yet, from what we tried, we would recommend PX4 with ROS and Gazebo for your project regarding our work and the previous one. In fact, it is the same architecture as Ardupilot but with ROS dependencies "built in" (PX4 and ROS are working together to give us this solution). Even though the documentation, examples and community is bigger for Ardupilot, we think that PX4 open source documentation would me enough.
The hector package is not to put away because of its versatility and utility with other solutions (such as ArduPilot); and DJI Assistant should be tried as you have the chance to already got the Hardware.
There are two branch that have been created depending on which ROS version is used (Kinetic or Melodic).
-
In the kinetic branch there are the explanation about the DJI assistant test along with the installation file.
-
In the melodic branch there are one markdown file for each method we tried : hector_quadrotor package and ArduPilot
We also created a folder with all the pictures that illustrate our markdown files and some extra graph.