scripts/arm_ros_conn.py

   1 #!/usr/bin/env python
   2 # -*- coding: iso-8859-15 -*-
   3
   4 import sys
   5 import rospy
   6 import arm
   7 import actionlib
   8 import numpy as np
   9 from sensor_msgs.msg import JointState
  10 from control_msgs.msg import FollowJointTrajectoryAction, FollowJointTrajectoryActionResult, FollowJointTrajectoryActionFeedback, FollowJointTrajectoryResult
  11 from control_msgs.msg import GripperCommandAction
  12 from actionlib_msgs.msg import GoalStatus
  13 from time import sleep
  14 from math import *
  15
  16 lJointNames = ["arm_base_to_link1", "link_1_2_joint", "link_2_3_joint", "link_3_4_joint", "link_4_5_joint", "left_gripper_joint", "right_gripper_joint"]
  17
  18
  19 class ARMRosConn():
  20         _feedback = FollowJointTrajectoryActionFeedback()
  21         _result = FollowJointTrajectoryActionResult()
  22
  23         def __init__(self):
  24                 rospy.init_node('arm')
  25
  26                 self.speed = 220
  27                 self.lAngles = [0] * 6
  28                 arm.switch(0)
  29                 arm.switch(2)
  30                 arm.set_hall_mode(3, 0)
  31                 arm.set_hall_mode(5, 0)
  32                 arm.set_tolerance(3, 0)
  33                 arm.set_tolerance(5, 0)
  34
  35                 self._as_arm = actionlib.SimpleActionServer("arm_controller/follow_joint_trajectory", FollowJointTrajectoryAction, execute_cb=self.execute_joint_trajectory, auto_start = False)
  36                 self._as_arm.start()
  37                 self._as_gripper = actionlib.SimpleActionServer("gripper_controller/gripper_action", GripperCommandAction, execute_cb=self.execute_gripper_action, auto_start = False)
  38                 self._as_gripper.start()
  39                 self.pub_joint_states = rospy.Publisher("joint_states", JointState, queue_size=16)
  40                 self.run()
  41
  42         def run(self):
  43                 rate = rospy.Rate(20)
  44                 while not rospy.is_shutdown():
  45                         self.publish_joint_states()
  46                         rate.sleep()
  47
  48         def publish_joint_states(self):
  49                 joint_state = JointState()
  50                 joint_state.header.stamp = rospy.Time.now()
  51                 joint_state.name = lJointNames
  52                 self.lAngles = [-arm.get_angle(0), arm.get_angle(1), -arm.get_angle(2), -arm.get_angle(3), arm.get_angle(4), arm.get_angle(5)]
  53                 joint_state.position = self.lAngles[:-1] + [0.175-self.lAngles[-1]/2, 0.175-self.lAngles[-1]/2]
  54                 self.pub_joint_states.publish(joint_state)
  55
  56         def execute_joint_trajectory(self, goal):
  57                 self._result.status = FollowJointTrajectoryResult.SUCCESSFUL
  58                 for point in goal.trajectory.points:
  59                         print goal.trajectory.joint_names
  60                         print point.positions
  61                         lGoalPosOrdered = [
  62                                 point.positions[goal.trajectory.joint_names.index(lJointNames[0])],
  63                                 point.positions[goal.trajectory.joint_names.index(lJointNames[1])],
  64                                 point.positions[goal.trajectory.joint_names.index(lJointNames[2])],
  65                                 point.positions[goal.trajectory.joint_names.index(lJointNames[3])],
  66                                 point.positions[goal.trajectory.joint_names.index(lJointNames[4])],
  67                         ]
  68                         try:
  69                                 arm.to_angle(0, self.speed, -lGoalPosOrdered[0])
  70                                 arm.to_angle(1, self.speed,  lGoalPosOrdered[1])
  71                                 arm.to_angle(2, self.speed, -lGoalPosOrdered[2])
  72                                 arm.to_angle(3, self.speed, -lGoalPosOrdered[3])
  73                                 arm.to_angle(4, self.speed,  lGoalPosOrdered[4])
  74                         except arm.RangeError as e:
  75                                 print >> sys.stderr, e.message
  76                                 self._feedback.status = GoalStatus.REJECTED
  77                                 self._as_arm.publish_feedback(self._feedback.feedback)
  78                                 self._result.status = FollowJointTrajectoryResult.INVALID_GOAL
  79                                 break
  80
  81                         error = 0
  82                         while True:
  83                                 error = np.array(lGoalPosOrdered) - np.array(self.lAngles[:-1])
  84                                 print "Error", error
  85                                 if all(f < 0.02 for f in error):
  86                                         break
  87
  88                                 if self._as_arm.is_preempt_requested():
  89                                         self._as_arm.set_preempted()
  90                                         break
  91                                 sleep(0.001)
  92
  93                         self._feedback.status = GoalStatus.SUCCEEDED
  94                         self._feedback.feedback.joint_names = lJointNames[:-1]
  95                         self._feedback.feedback.desired.positions = lGoalPosOrdered
  96                         self._feedback.feedback.actual.positions = self.lAngles[:-1]
  97                         self._feedback.feedback.error.positions = error
  98                         self._as_arm.publish_feedback(self._feedback.feedback)
  99                 self._as_arm.set_succeeded(self._result.result)
 100
 101
 102         def execute_gripper_action(self, goal):
 103                 print goal
 104
 105 if __name__ == '__main__':
 106         ARMRosConn()