isyhand_interface

ROS 2 interface package providing custom messages for the IsyHand.

• Package manifest: package.xml
• Build file: CMakeLists.txt

Messages

• isyhand_interface/msg/JointState.msg — current state of hand joints (header, joint ids, encoder/radian/scale positions, currents, temperatures).
• isyhand_interface/msg/CommandJointPos.msg — commanded joint positions (header, joint ids, encoder or scaled positions). RL policies can be trained to output actions between -1 and 1. In this case, use scaled positions.

Quick overview of the messages

• isyhand_interface/msg/JointState.msg
  • std_msgs/Header header — ROS header for timestamps/frame.
  • string[] joint_names - Dynamixel motor IDs
  • int32[] absolute_positions — encoder units
  • float32[] radian_positions
  • float32[] scale_positions - units scaled between -1 and +1 corresponding to the ranges of the motors defined by the robot urdf.
  • int32[] currents
  • int32[] temperatures
• isyhand_interface/msg/CommandJointPos.msg
  • std_msgs/Header header
  • string[] joint_names
  • int32[] absolute_positions
  • float32[] scaled_positions

Build / install

1. Place this package in a ROS 2 workspace src/ directory.
2. From the workspace root: colcon build
3. Source the install setup: source install/setup.bash

Example:

# Publish a JointState (one-shot)
ros2 topic pub /isyhand/joint_states isyhand_interface/msg/JointState "{ header: {stamp: {sec: 0, nanosec: 0}, frame_id: ''}, joint_names: ['thumb'], absolute_positions: [123], radian_positions: [1.57], scale_positions: [0.5], currents: [100], temperatures: [30] }"

# Echo the topic
ros2 topic echo /isyhand/joint_states

License

• Apache License 2.0 (see package.xml).

Contact

• Maintainer: Ben Richardson (ben.richardson.830@gmail.com)