View source for Webots

{{Short description|Open-source robot simulator}}
{{Infobox software
| name =
| screenshot = Wbinterface.png
| screenshot size = 230px
| caption = Autonomous car in Webots
| latest_release_version = Webots R2023b
| latest release date = June 28th, 2023
| developer = Cyberbotics Ltd.
| operating_system = [[Windows]], [[Linux]], [[macOS]]
| genre = [[Robotics simulator]]
| license = [[Apache License#Version 2.0|Apache 2]]
| website = [http://www.cyberbotics.com Cyberbotics Web page]
| repo = [https://github.com/cyberbotics/webots GitHub]
}}
'''Webots''' is a free and open-source 3D [[robot simulator]] used in industry, education and research.
The Webots project started in 1996, initially developed by Dr. Olivier Michel at the Swiss Federal Institute of Technology ([[EPFL]]) in [[Lausanne]], [[Switzerland]] and then from 1998 by Cyberbotics Ltd. as a proprietary licensed software. Since December 2018, it is released under the free and open-source [[Apache License#Version 2.0|Apache 2 license]].<ref name="openSourceAnnounce">{{cite web
| publisher = Cyberbotics
| year = 2018
| url = https://www.cyberbotics.com/doc/blog/Webots-2019-a-release
| title = Version R2019a - Webots Goes Open Source
}}</ref>
Webots includes a large collection of freely modifiable models of robots, sensors, actuators and objects. In addition, it is also possible to build new models from scratch or import them from 3D CAD software. When designing a robot model, the user specifies both the graphical and the physical properties of the objects. The graphical properties include the shape, dimensions, position and orientation, colors, and texture of the object. The physical properties include the mass, friction factor, as well as the spring and [[Damping ratio|damping]] constants. Simple fluid dynamics is present in the software.
Webots uses a fork of the ODE ([[Open Dynamics Engine]]) for detecting of collisions and simulating rigid body dynamics. The ODE library allows one to accurately simulate physical properties of objects such as velocity, inertia and friction.
Webots includes a set of sensors and actuators frequently used in robotic experiments, e.g. lidars, radars, [[proximity sensors]], light sensors, touch sensors, [[GPS]], [[accelerometer]]s, cameras, emitters and receivers, servo motors (rotational & linear), position and force sensor, LEDs, grippers, gyros, compass, IMU, etc.
The robot controller programs can be written outside of Webots in [[C (programming language)|C]], [[C++]], [[Python (programming language)|Python]], [[Robot Operating System|ROS]], [[Java (programming language)|Java]] and [[MATLAB]] using a simple API.
Webots offers the possibility to take screenshots and record simulations. Webots worlds are stored in cross-platform *.wbt files whose format is based on the [[VRML]] language. One can also import and export Webots worlds and objects in the VRML format. Users can interact with a running simulation by moving robots and other objects with the mouse. Webots can also stream a simulation on web browsers using [[WebGL]].
[[File:Robotisop3.png|alt=|thumb|230x230px|Simulation of a Robotis-Op3in Webots]]
[[File:Pioneer3at.png|alt=|thumb|230x230px|Simulation of a Pioneer 3-AT (Adept Mobile Robots) mounted with a SICK LMS 291 in Webots]]
[[File:Pioneer3DX.png|thumb|230px|Simulation of a Pioneer 3-DX (Adept Mobile Robots) in Webots]]
[[File:Pr2.png|alt=|thumb|A simulation model of the PR2 robot in Webots.]]
[[File:Khepera3.png|alt=|thumb|A simulation model of the Khepera III robot with gripper in Webots.]]
[[File:SalamanderSimu.png|alt=|thumb|A simulation model of a salamander robot in Webots which has a deformable skin.]]
[[File:Atlas robot 3D model.png|thumb|A simulation model of the Boston Dynamics Atlas robot in Webots.]]
== Web interface ==
Since August 18, 2017, the robotbenchmark.net website has offered free access to a series of robotics benchmarks based on Webots simulations through the Webots web interface. Webots instances are running in the cloud and the 3D views are displayed in the user browser. From this web interface, users can program robots in Python and learn robot control in a step-by-step procedure.
== Controller programming example ==
This is a simple example of C/C++ controller programming with Webots: a trivial collision avoidance behavior. Initially, the robot runs forwards, then when an obstacle is detected it rotates around itself for a while and then resumes the forward motion.
<syntaxhighlight lang="c">
#include <webots/robot.h>
#include <webots/motor.h>
#include <webots/distance_sensor.h>
#define TIME_STEP 64
int main() {
// initialize Webots
wb_robot_init();
// get handle and enable distance sensor
WbDeviceTag ds = wb_robot_get_device("ds");
wb_distance_sensor_enable(ds, TIME_STEP);
// get handle and initialize the motors
WbDeviceTag left_motor = wb_robot_get_device("left_motor");
WbDeviceTag right_motor = wb_robot_get_device("right_motor");
wb_motor_set_position(left_motor, INFINITY);
wb_motor_set_position(right_motor, INFINITY);
wb_motor_set_velocity(left_motor, 0.0);
wb_motor_set_velocity(right_motor, 0.0);
// control loop
while (1) {
// read sensors
double v = wb_distance_sensor_get_value(ds);
// if obstacle detected
if (v > 512) {
// turn around
wb_motor_set_velocity(left_motor, -600);
wb_motor_set_velocity(right_motor, 600);
}
else {
// go straight
wb_motor_set_velocity(left_motor, 600);
wb_motor_set_velocity(right_motor, 600);
}
// run a simulation step
wb_robot_step(TIME_STEP);
}
wb_robot_cleanup();
return 0;
}
</syntaxhighlight>
== Main fields of application ==
* Fast prototyping of wheeled and legged robots
* Research on robot locomotion<ref name="sDegallier07">{{cite web
| publisher = Biologically Inspired Robotics Group
| year = 2007
| url = http://birg2.epfl.ch/publications/fulltext/sDegallier07.pdf
| title = Hand placement during quadruped locomotion in a humanoid robot: A dynamical system approach
| format = PDF }}</ref>
* [[Swarm intelligence]] (Multi-robot simulations)<ref name="jPugh08">{{cite web
| publisher = Swarm-Intelligent Systems Group
| year = 2008
| url = http://infoscience.epfl.ch/record/118629
| title = Distributed Adaptation in Multi-Robot Search using Particle Swarm Optimization}}</ref><ref name="cCianci08">{{cite web
| publisher = DISAL - Distributed Intelligent Systems and Algorithms Laboratory
| year = 2008
| url = http://infoscience.epfl.ch/record/125777/files/Cianci_SIS2008.pdf
| title = Assembly of Configurations in a Networked Robotic System: A Case Study on a Reconfigurable Interactive Table Lamp
| format = PDF}}</ref>
* [[Artificial life]] and [[evolutionary robotics]]
* Simulation of adaptive behaviour<ref name="leMartinet11">Louis-Emmanuel Martinet, Denis Sheynikhovich, Karim Benchenane, and Angelo Arleo (2011) Spatial Learning and Action Planning in a Prefrontal Cortical Network Model, PLoS Comput Biol 7(5): e1002045. {{doi|10.1371/journal.pcbi.1002045}}</ref><ref name="fManella08">Mannella F., Mirolli M., Baldassarre G., A computational model of the amygdala nuclei's role in second order conditioning. In M. Asada et al. (eds.), From Animals to Animats 10: Proceedings of the Tenth International Conference on the Simulation of Adaptive Behavior (SAB2008), pp. 321-330. LNAI 5040 Berlin: Springer.</ref>
* [[Self-Reconfiguring Modular Robotics]]<ref name="aSproewitz08">{{cite web
| publisher = Biologically Inspired Robotics Group
| year = 2008
| url = http://birg2.epfl.ch/publications/fulltext/aSproewitz08.pdf
| title = An active connection mechanism for modular self-reconfigurable robotic systems based on physical latching
| format = PDF }}</ref>
* Experimental environment for [[computer vision]]
* Teaching and robot programming contests
== Included robot models ==
A complete and up-to-date list is provided in the Webots user guide.
* [[AIBO]] ERS7 and ERS210,<ref name = "hohl06">{{cite web
| publisher = Biologically Inspired Robotics Group
| year = 2006
| url = http://birg2.epfl.ch/publications/fulltext/hohl06.pdf
| title = Aibo and webots: Simulation, wireless remote control and controller transfer
| format = PDF}}</ref> [[Sony]] Corporation
* BIOLOID (dog), Robotis<ref>[[Bioloid]]</ref>
* Boe-Bot
* DARwIn-OP, Robotis
* [[E-puck]]
* Hemisson
* HOAP-2, [[Fujitsu]] Limited
* [[iCub]], [[RobotCub Consortium]]
* [[iRobot Create]], [[iRobot]]
* Katana IPR, Neuronics AG
* [[Khepera mobile robot]] I, II, III, K-Team Corporation
* KHR-2HV, KHR-3HV, Kondo
* Koala, K-Team Corporation
* [[Lego Mindstorms]] (RCX Rover model)
* Magellan
* [[Nao (robot)|Nao]] V2, V3, Aldebaran Robotics
* MobileRobots Inc Pioneer 2, Pioneer 3-DX, Pioneer 3-AT
* Puma 560, [[Unimate]]
* Scout 2
* Shrimp III, BlueBotics SA
* Surveyor SRV-1, Surveyor Corporation
* youBot, [[KUKA]]
== Cross compilation and remote control support ==
* [[E-puck]]
* [[DARwIn-OP]] and Robotis OP2
* [[Nao (robot)|NAO]]
* [[Thymio|Thymio II]]
== See also ==
* [[Robot Operating System|ROS]]
* [[E-puck]]
==References==
{{Reflist}}
== External links ==
{{Commons category}}
* [https://cyberbotics.com Cyberbotics]
[[Category:Robotics simulation software]]
[[Category:1996 software]]
[[Category:1996 in robotics]]
[[Category:Driving simulators]]