Hand Commander


The SrHandCommander inherits all methods from the robot commander and provides commands specific to the hand. It allows the state of the tactile sensors and joints effort to be read, and the maximum force to be set.


Import the hand commander along with basic rospy libraries and the hand finder:

import rospy
from sr_robot_commander.sr_hand_commander import SrHandCommander
from sr_utilities.hand_finder import HandFinder

The constructor for the SrHandCommander takes a name parameter that should match the group name of the robot to be used. Also it takes the hand prefix, parameters and serial number that can be retrieved using the HandFinder.


# Using the HandFinder
hand_finder = HandFinder()
hand_parameters = hand_finder.get_hand_parameters()
hand_serial = hand_parameters.mapping.keys()[0]

# If name is not provided, it will set "right_hand" or "left_hand" by default, depending on the hand.
hand_commander = SrHandCommander(name = "rh_first_finger",

# Alternatively you can launch the hand directly
hand_commander = SrHandCommander(name = "right_hand", prefix = "rh")

Getting information

Use the get_joints_effort method to get a dictionary with efforts of the group joints.

hand_joints_effort = hand_commander.get_joints_effort()
print("Hand joints effort \n " + str(hand_joints_effort) + "\n")

Use the get_tactile_type to get a string indicating the type of tactile sensors present (e.g. PST, biotac, UBI0) or get_tactile_state to get an object containing tactile data. The structure of the data is different for every tactile_type .

tactile_type = hand_commander.get_tactile_type()
tactile_state = hand_commander.get_tactile_state()

print("Hand tactile type\n" + tactile_type + "\n")
print("Hand tactile state\n" + str(tactile_state) + "\n")

Set the maximum force

Use the method set_max_force to set the maximum force for a hand joint.


  • joint_name name of the joint.
  • value maximum force value


## The limits in the current implementation of the firmware are from 200 to 1000 (measured in custom units)
hand_commander.set_max_force("rh_FFJ3", 600)