operator_node

The operator_node package provides tools for mapping raw interface commands to operator signals.

Nodes

joy_remap

Recieves joy messages from a joy_node and republishes at a given sampling frequency. Sometimes I have noticed the sampling frequency of a joy_node does not always match the observed frequency (the difference is typically fairly small but significant).

Parameters

• ~hz (int, default: 100)

  Sampling frequency.

Subscribed topics

• joy_in (sensor_msgs/Joy)

  Raw signals from interface driver.

Published topics

• joy_out (sensor_msgs/Joy)

  Raw signals from interface driver published at given sampling frequency.

operator_interface_logger

This node collects a log of the previous N operator signals and publishes this including timestamps as a flattened std_msgs/Float64MultiArray message. The window duration is given in time (seconds).

You can think of the log as being a (1+Nd)-by-N array that has been flattened by columns. N is the number of signals in the current buffer. Nd is the number of dimensions of the operator signal, and the 1 is for the time stamp.

Parameters

• ~window_duration (float)

  The operator signals recieved within this window of time will be published on each topic.

Subscribed topics

• operator_node/signal (std_msgs/Float64MultiArray)

  Operator signals.

Published topics

• operator_node/window (std_msgs/Float64MultiArray)

  A list of operator signals recieved in the previous window of time. Note, a helper function in Python is provided named reconstruct_interface_log_msg, see example:

  import rospy
  import operator_node
  from std_msgs.msg import Float64MultiArray
  
  Nd = 2  # number of dims for operator signal
  
  def callback(msg):
      t, h = operator_node.parser.reconstruct_interface_log_msg(msg, Nd)
      print("-"*70)
      print(f"{t = }")
      print(f"{h = }")
  
  rospy.init_node('test')
  rospy.Subscriber('operator_node/window', Float64MultiArray, callback)
  rospy.spin()

isometric_node.py

Scale the interface axes but ensure isometric.

Parameters

• ~config/axes_idx (list[int])

  Indicices of the axes to be used to generate operator signal.

• ~config/scale (float, min: 0.0, max: inf, default: 1.0)

  Maximum operator signal magnitude.

• ~start_on_init (bool, default: False)

  Start the subscriber on initialization. Otherwise use a service to toggle subscriber on/off.

Subscribed topics

• joy (sensor_msgs/Joy)

  Interface signals.

Published topics

• operator_node/signal (std_msgs/Float64MultiArray)

  Operator signals.

Services

• operator_node/toggle (std_srvs/SetBool)

  Toggle the operator node on/off.

scale_node.py

Simply scale each interface axes.

Parameters

• ~config/axes_idx (list[int])

  Indicices of the axes to be used to generate operator signal.

• ~config/scale (either: list[float], float, default: 1.0)

  Maximum operator signal magnitude along each dimension.

• ~start_on_init (bool, default: False)

  Start the subscriber on initialization. Otherwise use a service to toggle subscriber on/off.

Subscribed topics

• joy (sensor_msgs/Joy)

  Interface signals.

Published topics

• operator_node/signal (std_msgs/Float64MultiArray)

  Operator signals.

Services

• operator_node/toggle (std_srvs/SetBool)

  Toggle the operator node on/off.

keyboard_to_joy.py

Map keyboard events to sensor_msgs/Joy messages.

Parameters

• ~config (dict)

  Configuration file, see example in configs/.

• ~hz (int, default: 100)

  Sampling frequency.

Subscribed topics

• keyboard/keyup (keyboard/Key)

  Keyboard key-up events.

• keyboard/keydown (keyboard/Key)

  Keyboard key-down events.

Published topics

• joy (sensor_msgs/Joy)

  Joy messages representing keyboard events.