sr_right_hand_arm_ef_pos.py

Go to the documentation of this file.

#!/usr/bin/env python
# Copyright 2020 Shadow Robot Company Ltd.
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the Free
# Software Foundation version 2 of the License.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
# more details.
#
# You should have received a copy of the GNU General Public License along
# with this program. If not, see <http://www.gnu.org/licenses/>.

# This example demonstrates some of the functions of the arm commander using poses.
# The arm is moved through a sequence of goals generated via different pose functions in the commander.
# A pose can be a PoseStamped message,
# or a list of 6 floats: [x, y, z, rot_x, rot_y, rot_z],
# or a list of 7 floats [x, y, z, qx, qy, qz, qw]
# PLEASE NOTE: move_to_joint_value_target_unsafe is used in this script, so collision checks
# between the hand and arm are not made!

# For more information, please see:
# https://dexterous-hand.readthedocs.io/en/latest/user_guide/2_software_description.html#robot-commander

# roslaunch commands used with this script to launch the robot:
# real robot with a NUC (or a separate computer with an RT kernel):
#     roslaunch sr_robot_launch sr_right_ur10arm_hand.launch
#               external_control_loop:=true sim:=false scene:=true
# simulated robot:
#     roslaunch sr_robot_launch sr_right_ur10arm_hand.launch sim:=true scene:=true

# It is recommended to run this script in simulation first.

import rospy
import sys
from trajectory_msgs.msg import JointTrajectory, JointTrajectoryPoint
from sr_robot_commander.sr_robot_commander import SrRobotCommander
from sr_robot_commander.sr_arm_commander import SrArmCommander

rospy.init_node("right_hand_arm_ef_pos", anonymous=True)

# The constructors for the SrArmCommander, SrHandCommander and SrRobotCommander
# take a name parameter that should match the group name of the robot to be used.
# How to command the arm separately
arm_commander = SrArmCommander(name="right_arm")
# How to command the arm and hand together
robot_commander = SrRobotCommander(name="right_arm_and_hand")
arm_commander.set_max_velocity_scaling_factor(0.1)

rospy.sleep(2.0)

arm_home_joints_goal = {'ra_shoulder_pan_joint': 0.00, 'ra_elbow_joint': 2.00,
                        'ra_shoulder_lift_joint': -1.25, 'ra_wrist_1_joint': -0.733,
                        'ra_wrist_2_joint': 1.5708, 'ra_wrist_3_joint': 0.00}

arm_hand_home_joints_goal = {'ra_shoulder_pan_joint': 0.00, 'ra_elbow_joint': 2.00,
                             'ra_shoulder_lift_joint': -1.25, 'ra_wrist_1_joint': -0.733,
                             'ra_wrist_2_joint': 1.5708, 'ra_wrist_3_joint': 0.00,
                             'rh_THJ1': 0.52, 'rh_THJ2': 0.61, 'rh_THJ3': 0.0, 'rh_THJ4': 1.20,
                             'rh_THJ5': 0.17, 'rh_FFJ1': 1.5707, 'rh_FFJ2': 1.5707, 'rh_FFJ3': 1.5707,
                             'rh_FFJ4': 0.0, 'rh_MFJ1': 1.5707, 'rh_MFJ2': 1.5707, 'rh_MFJ3': 1.5707,
                             'rh_MFJ4': 0.0, 'rh_RFJ1': 1.5707, 'rh_RFJ2': 1.5707, 'rh_RFJ3': 1.5707,
                             'rh_RFJ4': 0.0, 'rh_LFJ1': 1.5707, 'rh_LFJ2': 1.5707, 'rh_LFJ3': 1.5707,
                             'rh_LFJ4': 0.0, 'rh_LFJ5': 0.0, 'rh_WRJ1': 0.0, 'rh_WRJ2': 0.0}

example_goal_1 = [0.9, 0.16, 0.95, -0.99, 8.27, -0.0, 1.4]

example_goal_2 = [0.7, 0.16, 0.95, -0.99, 8.27, -0.0, 1.4]

# Evaluate the plan quality from starting position of robot.
# https://github.com/shadow-robot/sr_interface/blob/melodic-devel/sr_robot_commander/src/sr_robot_commander/sr_robot_commander.py#L263-L310
# This is to confirm that the arm is in a safe place to move to the home joints goal,
# if the outcome is poor please refer to the readthedocs of where the start arm home position is.
arm_to_home_plan = arm_commander.plan_to_joint_value_target(arm_home_joints_goal)
arm_to_home_plan_quality = arm_commander.evaluate_given_plan(arm_to_home_plan)
eval_arm_home_plan_quality = arm_commander.evaluate_plan_quality(arm_to_home_plan_quality)

if eval_arm_home_plan_quality != 'good':
    rospy.logfatal("Plan quality to the home position is poor! " +
                   "For safety please refer to the hand and arm documentation " +
                   "for where to start the arm " +
                   "to ensure no unexpected movements during plan and execute.")
    sys.exit("Exiting script to allow for the arm to be manually moved to better start position ...")

# Execute arm to home plan
rospy.loginfo("Planning and moving arm to home joint states\n" + str(arm_home_joints_goal) + "\n")
arm_commander.execute_plan(arm_to_home_plan)
rospy.sleep(2.0)

# The arm commander generates a plan to a new pose before the pose is executed.
# https://github.com/shadow-robot/sr_interface/blob/melodic-devel/sr_robot_commander/src/sr_robot_commander/sr_robot_commander.py#L668
raw_input("Press Enter to continue...")
rospy.loginfo("Planning the move to the first pose:\n" + str(example_goal_1) + "\n")
arm_commander.plan_to_pose_target(example_goal_1)
rospy.loginfo("Finished planning, moving the arm now.")
# Can only execute if a plan has been generated.
arm_commander.execute()
rospy.sleep(2.0)

# Here a pose is provided and the arm commander moves the arm to it
# https://github.com/shadow-robot/sr_interface/blob/melodic-devel/sr_robot_commander/src/sr_robot_commander/sr_robot_commander.py#L655
raw_input("Press Enter to continue...")
rospy.loginfo("Moving arm to pose:\n" + str(example_goal_2) + "\n")
arm_commander.move_to_pose_target(example_goal_2, wait=True)
rospy.sleep(2.0)

# Finish arm at home and hand at pack
raw_input("Press Enter to continue...")
rospy.loginfo("Moving arm to joint states\n" + str(arm_hand_home_joints_goal) + "\n")
robot_commander.move_to_joint_value_target_unsafe(arm_hand_home_joints_goal, 6.0, True)
rospy.sleep(3.0)