The Player universal driver and the The Player universal driver and the Stage and Gazebo simulatorsStage and Gazebo simulators

Daniele Calisi

Player, Stage and Gazebo - OpenRDK Workshop - March 2009 2

The Player/Stage/Gazebo projectThe Player/Stage/Gazebo project Long term project

Started in 2000 Moved to SourceForge in 2001 Gazebo (3D simulator) development started in 2003

The project maintains three piece of software: Player: a universal driver for robotics Stage: scalable 2D multiple robot simulator Gazebo: high-fidelity 3D multiple robot simulator

“Player is a collaborative development effort aimed at producing high-quality open source tools for robotics researchers” 7 active core developers (Player + Stage + Gazebo) 17 contributors Funding by DARPA, NSF, SRI, ONR, JPL Many organizations provide facilities Thousand of downloads per month

Player, Stage and Gazebo - OpenRDK Workshop - March 2009 3

What is PlayerWhat is Player Addresses two problems

There is a huge variety of hardware related to robotics (robot bases, sensors, actuators, etc.), each of which has its own interface, connection (Serial, USB, Ethernet, I2C, CAN-bus, etc.) and protocol

In the robotic scientific community, “the wheel gets reinvented over and over again”

The goal Provides a “robotic operating system” that hides hardware

details and uses standard interfaces (in the same way an operating system allows the user to interact to the hardware using drivers)

Provides standard basic tools for robotic researchers (e.g. viewers, simulators, etc.)

Support code reuse

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The Player structureThe Player structure

Player(server)

Controller(client)

Controller(client)

Controller(client)

Controller(client)

Player(server)

TCP, UDP,Jini, Ice

RS232, USB, 1394, TCP, Shared Mem

Stage (2D simulation)Gazebo (3D simulation)

© Brian Gerkey

Player, Stage and Gazebo - OpenRDK Workshop - March 2009 5

Supported hardware and interfacesSupported hardware and interfaces Robot bases

ActivMedia, RWI, Erratic, Segway Evolution, Nomadics...

Laser range finders SICK, Hokuyo

Vision ACTS, CMVision, CMUCam

PTZ Sony, Canon, Amtec, Direct Perceptions

IMU ISense, XSens, ...

GPS Speech

Festival, Sphinx2

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Player and OpenRDKPlayer and OpenRDK

Different goals Player is (mostly) an interface to the hardware/simulators OpenRDK is a framework for higher-level processing and

behaviors

player2client

localizer

mapper

Player

Hardware/SimulatorClients

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How to configure PlayerHow to configure Player

Player is run with a configuration file that specifies the devices to be used

Exampledriver ( name "p2os" provides [ "odometry:::position2d:0" "sonar:0" "power:0" "bumper:0" "gripper:::gripper:0" "blobfinder:0" "sound:0" ] port "/dev/ttyS0")

driver ( name "sicklms200" provides [ "laser:0" ] port "/dev/ttyS2")

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How to configure the OpenRDK agent (1)How to configure the OpenRDK agent (1)

Problem Simulator client modules (and Player2ClientModule

as well) often contains all properties for all sensors and actuators simulated

This results in a cluttered configuration file and property tree

Solution (coming soon) Optional properties allow the user to choose which

properties will be created This is one of the possible uses of initInterfaceProperties()

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How to configure the OpenRDK agent (2)How to configure the OpenRDK agent (2)

Example

Automatic loading from Player config file?

• Properties created in initConfigurationProperties()

/robot/params/groundTruthPoseEnabled=Yes/robot/params/laserConfig=laser0 laser1/robot/params/sonarConfig=/robot/params/gpsConfig=

• Properties created in initInterfaceProperties()

/robot/out/groundTruthPose/robot/out/laser0/laserData/robot/out/laser1/laserData

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Player and its simulatorsPlayer and its simulators

Stage 2D environment model Robot kinematics Light simulation

( O(1) ~ O(n) ) Large population of robots

(~100?) Indoor environments

Gazebo 3D environment model Robot dynamics Uses ODE

(Open Dynamics Engine) More expensive simulation

( O(n) ~ O(n3) ) Small robot teams

(~10?) Outdoor environments

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The Gazebo 3D simulatorThe Gazebo 3D simulator

Advantages- ODE for physics- 3D modeling

Problems- Proprietary XML format for world

and robot descriptions- No import facility from 3D modeling

software

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The Stage 2D simulatorThe Stage 2D simulator

2D environments and multiple robots

Light simulation The world is specified as

a text file and a B/W image

Fast and easy on-line interaction with the environment

Supports all Player sensors, moving objects, a simple vision simulation (BLOB finder), etc.

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A brief analysis of StageA brief analysis of Stage Intermediate simulation

Widely used If you need a 2D simulator, Stage is the choice

Simulation The Stage developer claims that simple simulation can make

you create robust algorithms (e.g., discretization, etc.) For this reason, no noise is added to sensor data or to actions,

“noise” is obtained indirectly through discretization

Grid world Complex 3D realistic simulatorStage

complexity

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Past and current OpenRDK + Stage usesPast and current OpenRDK + Stage uses Performance

measurements for motion algorithms (MoVeME benchmark database)

Multi-agent multi-object tracking

Coordination (token-passing technique) experiments

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How to use Player with StageHow to use Player with Stage

driver ( name "stage" provides [ "simulation:0" ]

plugin "libstageplugin" worldfile "hospital.world")

driver ( name "stage" provides [ "position2d:0" "laser:0" ]

model "robot1" samples 180 fov 180 range_min 0.0 range_max 4.0)

// ...

map ( bitmap "hospital.png" size [8 16] name "cave")

pioneer2dx ( name "robot1" color "red" pose [1 2 0] sick_laser())

Player configuration fileWorld file

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Thank you for your attentionThank you for your attention

Questions?Official Player/Stage website: http://playerstage.sf.net