== B21 ==
The B21 is a robot which uses the [[rflex|RFlex]] driver. 

== Features ==
 * Ring of 24 sonar sensors on its base
 * Ring of 24 sonar sensors on its body
 * Ring of 24 IR sensors on its body
 * 2 bumps sensors per panel
   * 12 on body, 16 on base

{{{
#!clearsilver CS/NodeAPI
name = B21
desc = Controls B21 type robots. Awesomely. 
sub {
  0.name = ~cmd_vel
  0.type = geometry_msgs/Twist
  0.desc = Motor Commands
  1.name = ~cmd_accel
  1.type = std_msgs/Float32
  1.desc = Translational acceleration
  2.name = ~cmd_sonar_power
  2.type = std_msgs/Bool
  2.desc = Turns the sonar on and off
  3.name = ~cmd_brake_power
  3.type = std_msgs/Bool
  3.desc = Turns the brake on and off
}
pub {
  0.name = ~sonar_cloud_base
  0.type = sensor_msgs/PointCloud
  0.desc = Point Cloud from Base. Uses base reference frame. 
  1.name = ~sonar_cloud_body
  1.type = sensor_msgs/PointCloud
  1.desc = Point Cloud from Body. Uses body reference frame. 
  2.name = ~sonar_power
  2.type = std_msgs/Bool
  2.desc = Broadcasts whether sonar is on
  3.name = ~brake_power
  3.type = std_msgs/Bool
  3.desc = Broadcasts whether brake is on
  4.name = ~voltage
  4.type = std_msgs/Float32
  4.desc = Current battery voltage
  5.name = ~odom
  5.type = nav_msgs/Odometry
  5.desc = Current odometry
  6.name = ~plugged_in
  6.type = std_msgs/Bool
  6.desc = Whether or not the robot's battery is plugged in
}
param {
  0.name = ~port
  0.type = String
  0.desc = Filename of port that the robot is connected on
  0.default = /dev/ttyUSB0
  1.name = ~rate
  1.type = Integer
  1.desc = Main loop rate in hertz
  1.default = 10
}
}}}