Ros by Example-12th chapter Dynamixel Servo Systems and ROS

Servo motor Selection Robotis Dynamixel, Bonzi brand. Real-time position feedback, speed and torque. Low end of the AX-12. A certain treasure on the cheapest also to 310RMB.

In this chapter, we will discuss the following topics:
• Add PTZ to Turtlebot
• Select Dynamixel Controller and Ros pack
• Understanding ROS Jointstate Message Types
• Use basic Joint control commands
• Connecting hardware controllers and setting up servo IDs
• Configured startup files and parameters
• Test the steering gear
• Head tracking Node programming
• Combination head face tracking

12.1 Turtlebot with Cloud table

$roslaunch rbx1_description test_turtlebot_with_head.launch
$rosrun rviz rviz-d ' rospack find rbx1_description '/ Urdf.rviz

12.2 Select a Dynamixel hardware controller

12.4 Select one Ros dynamixel pack

Arbotix the second volume says, dynamixel_motor

sudo apt-get install Ros-indigo-dynamixel-motor

12.5 Understanding ROS Jointstate Message Types

$rosmsg Show Sensor_msgs/jointstate

Header header
uint32 seq time
stamp
string frame_id
string[] name
float64[] position
float64 [] Velocity
float64[] Effort

12.6 control of joint position, speed and torque

12.6.1 Set Servo position

<joint_controller_name>/command

$rostopic pub-1/head_pan_joint/command Std_msgs/float64---1.0

12.6.2 Set Servo speed

$rosservice Call/head_pan_joint/set_speed 0.5

12.6.3 Control Servo Torque

The Dynamixel controller offers two kinds of torque services: Torque_enable or Set_torque_limit.

$rosservice call/head_pan_joint/torque_enable False
$rosservice call/head_pan_joint/torque_enable True

12.7 Check Usb2dynamixel Connection

12.8 setting the Servo hardware ID

12.9 Configuring and starting the Dynamixel controller