The Robotics Primer Workbook Developed by  USC, iRobot® and Microsoft® Robotics Studio

Categories: Software | Stage | Player

Group:Group Howto

Contents 1 Intro 2 Stage 3 Player 4 Exercise Code

Intro

Group robotics typically require a number of physical robots to conduct an exercise. However, given the fact that you may not have a dozen Roomba/Creates lying around, you can make use of a simulator to create a series of robots.

Stage

Using the stage simulator, a great number of robots can be created. Here is an example stage world file that uses 11 robots:

# Desc: Stage demo with lots of models. Works with everything.cfg.
# CVS: $Id: everything.world,v 1.85 2006/03/29 05:11:00 rtv Exp $

# the size of a pixel in Stage's underlying raytrace model in meters
resolution     0.02

interval_sim 100  # milliseconds per update step
interval_real 100 # real-time milliseconds per update step

# defines Pioneer-like robots
include "pioneer.inc"

# defines 'map' object used for floorplans
include "map.inc"

# defines the laser model `sick_laser' configured like a Sick LMS-200
include "sick.inc"

size [20 20 ]

gui_disable 0
gui_interval 100
gui_menu_interval 20

window( 
  size [ 800 800.000 ] 
  center [0 0 ] 
  scale 0.025 
)

map( 
  bitmap "blank-room.png" 
  map_resolution 0.02
  size [20 20] 
  name "hospital"
)

# extend the pioneer2dx definition from pioneer.inc
#
define trickedoutpioneer pioneer2dx
(
  sick_laser(  
    pose [0.030 0.000 0.000 ]
    fiducialfinder( range_max 8 range_max_id 5 ) 

    ptz(
      blobfinder( 
        channel_count 6 
        channels [ "red" "blue" "green" "cyan" "yellow" "magenta" ]  
      )
    )
  )

  fiducial_return 1
  gripper_return 0

  localization "gps"
  localization_origin [ 0 0 0 ]

  bumper( bcount 3  
	  blength 0.2
          bpose[0] [0 -0.165  90]
          bpose[1] [0  0.165 -90] 
          bpose[2] [-0.26  0 0] 

	  blength[2] 0.1 # set the length of a single bumper
        )
)


trickedoutpioneer ( name "robot1" pose [ 0 0 0 ] )
trickedoutpioneer ( name "robot2" pose [ 0 5 0 ] )
trickedoutpioneer ( name "robot3" pose [ 0 6 0 ] )
trickedoutpioneer ( name "robot4" pose [ 0 3 0 ] )
trickedoutpioneer ( name "robot5" pose [ 3 5 0 ] )
trickedoutpioneer ( name "robot6" pose [ 4 5 0 ] )
trickedoutpioneer ( name "robot7" pose [ 5 5 0 ] )
trickedoutpioneer ( name "robot8" pose [ -4 -5 0 ] )
trickedoutpioneer ( name "robot9" pose [ -3 -5 0 ] )
trickedoutpioneer ( name "robot10" pose [ -2 -5 0 ] )
trickedoutpioneer ( name "robot11" pose [ -5 5 0 ] )

Save this file as everything.world. In addition to this file, a .png file is used as a model for the room:

Save this file as blank-room.png

Player

To control all of these robots, the following player file can be used:

# Desc: Player sample configuration file for controlling Stage devices
# Date: 18 Apr 2003
# CVS: $Id: everything.cfg,v 1.33 2006/03/29 05:11:00 rtv Exp $


driver
(		
  name "stage"
  provides ["simulation:0"]
  plugin "libstageplugin"
  worldfile "everything.world"	
)

driver( name "stage" provides ["map:0" ] model "hospital" )


# robot 0
driver( name "stage"  provides [ "position2d:0" "sonar:0" "laser:0" "ptz:0" "blobfinder:0" "fiducial:0" "graphics2d:0"  "bumper:0" ]  model "robot1" )

# robot 1
driver(  name "stage" provides [ "position2d:1" "sonar:1" "laser:1" "ptz:1" "blobfinder:1" "fiducial:1" "graphics2d:1"  "bumper:1" ]  model "robot2" )
driver(  name "stage" provides [ "position2d:2" "sonar:2" "laser:2" "ptz:2" "blobfinder:2" "fiducial:2" "graphics2d:2"  "bumper:2" ]  model "robot3" )
driver(  name "stage" provides [ "position2d:3" "sonar:3" "laser:3" "ptz:3" "blobfinder:3" "fiducial:3" "graphics2d:3"  "bumper:3" ]  model "robot4" )
driver(  name "stage" provides [ "position2d:4" "sonar:4" "laser:4" "ptz:4" "blobfinder:4" "fiducial:4" "graphics2d:4"  "bumper:4" ]  model "robot5" )
driver(  name "stage" provides [ "position2d:5" "sonar:5" "laser:5" "ptz:5" "blobfinder:5" "fiducial:5" "graphics2d:5"  "bumper:5" ]  model "robot6" )
driver(  name "stage" provides [ "position2d:6" "sonar:6" "laser:6" "ptz:6" "blobfinder:6" "fiducial:6" "graphics2d:6"  "bumper:6" ]  model "robot7" )
driver(  name "stage" provides [ "position2d:7" "sonar:7" "laser:7" "ptz:7" "blobfinder:7" "fiducial:7" "graphics2d:7"  "bumper:7" ]  model "robot8" )
driver(  name "stage" provides [ "position2d:8" "sonar:8" "laser:8" "ptz:8" "blobfinder:8" "fiducial:8" "graphics2d:8"  "bumper:8" ]  model "robot9" )
driver(  name "stage" provides [ "position2d:9" "sonar:9" "laser:9" "ptz:9" "blobfinder:9" "fiducial:9" "graphics2d:9"  "bumper:9" ]  model "robot10" )
driver(  name "stage" provides [ "position2d:10" "sonar:10" "laser:10" "ptz:10" "blobfinder:10" "fiducial:10"  "graphics2d:10" "bumper:10" ]  model "robot11" )

Save that file as everything.cfg. The simulator and player can be run with the command:

player everything.cfg

When that is done, a window such as this should appear:

Exercise Code

In the client.xml file, the following change should be made:

<?xml version='1.0'?>

<client xmlns:player='http://www.roombadev.com/xmlschema/psg/#player'
        xmlns:roomba='http://www.roombadev.com/xmlschema/psg/#roomba'>

  <player:params>
    <host>localhost</host>
    <port>6665</port>

    <num_clients>11</num_clients>
  </player:params>



</client>

Then when editing the exercise.cc file, robot client functions such as:

client->SetSpeed( 0.5, 0.0 );

become:

clients[i]->SetSpeed( 0.5, 0.0 );

where i is the robot number from 0..n-1

Notice the line:

    <num_clients>11</num_clients>

This tells the program to instantiate 11 robots using the player config file. This number defaults to 1.

client->SetSpeed, etc. still works, which defaults to clients[0].