Using Joysticks

Summary

A number of examples in the RSDK use game controllers, or joysticks, to interact with Baxter. There is also a python utility for handling input devices like joysticks with common methods.

• Overview
• Running the Example:
  • Keyboard Control
  • Joystick Control
    • (Alternative) Manual Start
• Recording Joint Positions
• Playback Recordings

Overview

Installing ROS Joystick Drivers

First ensure that the joy drivers are installed.

$ rospack find joy  

If not run:

$ sudo apt-get install ros-electric-joystick-drivers  

Substitute the appropriate ROS 'distro' for electric if you are running 'groovy' or other ROS versions.

Examples using joysticks

There are a couple RSDK examples already setup to use the joysticks to control Baxter. These can often be run in parallel with other tasks and programs and make it easier to position and coordinate Baxter while using the RSDK. Joystick examples include:

• Joint Position Example
• Gripper Example

Starting Joystick Example Programs

Examples that offer joystick integration will also include a start script specifically for starting up the joystick drivers

Using the PS3 Joystick

The PS3 SIXAXIS or DUALSHOCK3 joysticks require an additional component to run in order to support the bluetooth and special features of the joysticks. These drivers are thankfully taken care of in the ROS ps3joy package (included in the ros-<distro>-joystick-drivers install). To use the PS3 joystick, first you need to pair the joystick,

• joystart
• how it works, joy_node
• Supported joysticks
• Python support joystick.py

• Python Integration

Note: For control of Head Joints, see the Head Wobbler Example.

Keyboard Control

Start the example joint_position program using the keyboard to control Baxter:

$ rosrun joint_position keyboard.py

    hit ? for help commands
    esc to exit example and disable the robot

Joystick Control

To run the example joint_position program using a joystick game controller to control the joints:

First ensure that joy drivers are installed.

$ rospack find joy

If not run:

$ sudo apt-get install ros-electric-joystick-drivers

For Beta Version: To run the example:

$ rosrun joint_position joystart <joystick_type>  

Where <joystick_type> is 'xbox', 'logitech', or 'ps3'.
(If using a ps3, make sure you run the node from the ROS ps3joy package in a separate sudo terminal. See instructions here: ps3joy )

For Alpha Version: To run the example:

$ roslaunch joint_position joystick.launch joystick:=logitech

Note: This method uses an included ROS launch file to start both joint_position example and joy_node using the roslaunch tool. You can exit the joint_position example by hitting any keyboard key, however you will have to ctrl-c to also cleanup the joy_node.

Joystick Button Mappings

NOTE: Don't forget to calibrate each gripper before using gripper open/close.

(And no, the 'joystick left <-> robot right' mappings are not typos; they assume the user is in front of the robot when using the joystick.)

Buttons	Action	Buttons	Action
Function 1 or 2 (e.g. Select/Select)	Help	<Any Keyboard key>	Quit
Left Button (X)	right: gripper calibrate	Right Button (B)	left: gripper calibrate
Top Button (Y)		Bottom Button (A)
Left Trigger [PRESS]	right: gripper close	Right Trigger [PRESS]	left: gripper close
Left Trigger [RELEASE]	right: gripper open	Right Trigger [RELEASE]	left: gripper open
Left Bumper	right: cycle <current joints> +1	Right Bumper	left: cycle <current joints> +1

Stick Axes	Action
Left Stick Horizontal	right: increase/decrease <current joint 1> (s0)
Left Stick Vertical	right: increase/decrease <current joint 2> (s1)
Right Stick Horizontal	left: increase/decrease <current joint 1> (s0)
Right Stick Vertical	left: increase/decrease <current joint 2> (s1)

Press any keyboard key to quit.

Note: The left and right bumper buttons will cycle through the joints that are controlled with the left and right stick (<current joint 1> and <current joint 2>). The order the joints are cycled through is S0-S1-E0-E1-W0-W1-W2.

Alternative Manual Start

Alternatively, you can run the joint_position example and the joy_node (joystick driver) independently in their own shells:

1. Initialize an environment and run the joy_node:

$ cd ~/sdk-examples
$ ./init <robot_hostname>
$ export ROS_IP=<xxx.xxx.xxx.xxx>

$ rosrun joy joy_node

2. From another shell, repeat the initialization and run the example program:

# repeat lines 1-3 above
$ rosrun joint_position joystick.py logitech

For the joystick examples to work, the joy_node driver must be running at the same time as the example. Using any of the other one-line launch commands to start the joystick examples is really just using a short-cut to start two programs at once.

Recording Joint Positions

You can start recording the joint positions at any time using:

$ rosrun joint_position recorder.py <filename>

After you have finished recording, stop the joint_position program using <Ctrl-C> or hit one of the function 1 or 2 buttons on the game controller.

Playback Recordings

You can now playback the recording using:

$ rosrun joint_position file_playback.py <filename>