Package ROHand

ROS nodes for ROHand. One bus, i.e. one port need one node.

1. Clone

cd ~
mkdir -p ros_ws/src
cd ros_ws/src
git clone ssh://[email protected]/oymotion/rohand_ros_pkg

2. Prepare

Install pymodbus

cd /path/to/workspace  # Should be ~/ros_ws

# Create a vertual env for python
virtualenv -p python3 ./venv

# Make sure that catkin doesn’t try to build the venv
touch ./venv/CATKIN_IGNORE

# Activate
source ./venv/bin/activate

# Install python module
python3 -m pip install pymodbus

Edit ~/bashrc and add virtual env lib path to PYTHONPATH

export PYTHONPATH=$PYTHONPATH:~/ros_ws/venv/lib/python3.8/site-packages  # Modify python3.8 to your actual versioni
source ~/.bashrc

3. Compile

cd /path/to/workspace
catkin_make

4. Launch roscore

roscore

5. Node rohand

ROHand node for ModBus-RTU or ModBus-RTU & SerialCtrl Dual Protocol. Please confirm protocol type in OHandSetting. Listens to topic 'target_joint_state' and controls ROHand, reads current joint state and publish to 'current_joint_state'.

5.1 Topics

Topic	Description
"current_joint_state"	current joint state in message type JointState, frame_id in header distinguishes hand id
"target_joint_state"	target joint state in message type JointState, frame_id in header distinguishes hand id

5.2 Run

# Open a new terminal to prepare package
source /path/to/workspace/devel/bash

# Insert USB-485 module to USB port then add permission to users
# Run following command every time you plug in your USB-485 module
sudo chmod o+rw /dev/ttyUSB0  # Modify ttyUSB0 to your actual device name

# Run node
rosrun rohand rohand.py _port_name:=/dev/ttyUSB0 _baudrate:=115200 _hand_ids:=[2,3] # Modify parameters according to your real case

6. Node rohand_serial

ROHand node for SerialCtrl Protocol, Dual Protocol is NOT supported. Please confirm protocol type in OHandSetting. Listens to topic 'target_joint_state' and controls ROHand, reads current joint state and publish to 'current_joint_state'.

6.1 Topics

Topic	Description
"current_joint_state"	current joint state in message type JointState, frame_id in header distinguishes hand id
"target_joint_state"	target joint state in message type JointState, frame_id in header distinguishes hand id
"finger_state"	finger status in message type UInt8MultiArray

6.2 Run

# Open a new terminal to prepare package
source /path/to/workspace/devel/bash

# Insert USB-485 module to USB port then add permission to users
# Run following command every time you plug in your USB-485 module
sudo chmod o+rw /dev/ttyUSB0  # Modify ttyUSB0 to your actual device name

# Run node
rosrun rohand rohand_serial.py _port_name:=/dev/ttyUSB0 _baudrate:=115200 _hand_ids:=[2,3]  # Modify parameters according to your real case

Finger status code:

Name	Code	Description
STATUS_OPENING	0	Spreading
STATUS_CLOSING	1	Grasping
STATUS_POS_REACHED	2	Position reached stop
STATUS_OVER_CURRENT	3	Current protection stop
STATUS_FORCE_REACHED	4	Force control reached stop
STATUS_STUCK	5	Motor stuck stop

7. Node rohand_teleop

Reads keys to modify target joint angles, then publish to 'target_joint_state'.

7.1 Topics

Topic	Description
"target_joint_state"	target joint state in message type JointState, frame_id in header distinguishes hand id

7.2 Run

# Open a new terminal to prepare package
source /path/to/workspace/devel/bash

# Run node
rosrun rohand rohand_teleop.py _rohand_teleop_node/target_joint_states:=/rohand_node/target_joint_states _hand_id:=2  # Modify parameters according to your real case

Press following keys to operate:

key	Description
q	quit
a	thumb bends by step
z	thumb relaxes by step
s	index bends by step
x	index relaxes by step
d	middle bends by step
c	middle relaxes by step
f	ring bends by step
v	ring relaxes by step
g	little bends by step
b	little relaxes by step
h	thumb rotation +step
n	thumb rotation -step

Step is range / 10.