Transcript The Player universal driver and the Stage simulator

The Player universal driver and the
Stage and Gazebo simulators
Daniele Calisi
The Player/Stage/Gazebo project
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Long term project
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Started in 2000
 Moved to SourceForge in 2001
 Gazebo (3D simulator) development started in 2003
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The project maintains three piece of software:
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Player: a universal driver for robotics
 Stage: scalable 2D multiple robot simulator
 Gazebo: high-fidelity 3D multiple robot simulator
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“Player is a collaborative development effort aimed at producing
high-quality open source tools for robotics researchers”
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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
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What is Player
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Addresses two problems
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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
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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
Player, Stage and Gazebo - OpenRDK Workshop - March 2009
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The Player structure
Controller
(client)
Player
(server)
Gazebo (3D simulation)
Stage (2D simulation)
Controller
(client)
Controller
(client)
Player
(server)
Controller
(client)
TCP, UDP,
Jini, Ice
RS232, USB, 1394,
TCP, Shared Mem
Player, Stage and Gazebo - OpenRDK Workshop - March 2009
© Brian Gerkey
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Supported hardware and interfaces
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Robot bases
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Laser range finders
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Sony, Canon, Amtec, Direct Perceptions
IMU
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ACTS, CMVision, CMUCam
PTZ
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SICK, Hokuyo
Vision
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ActivMedia, RWI, Erratic, Segway
Evolution, Nomadics...
ISense, XSens, ...
GPS
Speech
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Festival, Sphinx2
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Player and OpenRDK
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Different goals
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Player is (mostly) an interface to the hardware/simulators
OpenRDK is a framework for higher-level processing and
behaviors
Clients
Hardware/Simulator
player2client
localizer
Player
mapper
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How to configure Player
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Player is run with a configuration file that
specifies the devices to be used
Example
driver (
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)
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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
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Solution (coming soon)
 Optional
properties allow the user to choose which
properties will be created
 This is one of the possible uses of
initInterfaceProperties()
Player, Stage and Gazebo - OpenRDK Workshop - March 2009
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How to configure the OpenRDK agent (2)
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Example
• 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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Automatic loading from Player config file?
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Player and its simulators
Stage
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2D environment model
Robot kinematics
Light simulation
( O(1) ~ O(n) )
Large population of robots
(~100?)
Indoor environments
Gazebo
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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 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 simulator
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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 Stage
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Intermediate simulation
Grid world
Stage
Complex 3D realistic simulator
complexity
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Widely used
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If you need a 2D simulator, Stage is the choice
Simulation
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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
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Past and current OpenRDK + Stage uses
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Performance
measurements for motion
algorithms (MoVeME
benchmark database)
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Multi-agent multi-object
tracking
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Coordination (tokenpassing technique)
experiments
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How to use Player with Stage
Player configuration file
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
World file
// ...
map (
bitmap "hospital.png"
size [8 16]
name "cave"
)
pioneer2dx (
name "robot1"
color "red"
pose [1 2 0]
sick_laser()
)
)
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Thank you for your attention
Questions?
Official Player/Stage website: http://playerstage.sf.net
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