def __init__(self):
self.paused = False
self.pauseCV = threading.Condition()
# load the node's parameters
self.arm_down_velocity = rospy.get_param('~arm_down_velocity', -0.5)
self.arm_down_torque = rospy.get_param('~arm_down_torque', 0.5)
self.arm_down_standoff = rospy.get_param('~arm_down_standoff', 0.1)
self.arm_up_velocity = rospy.get_param('~arm_up_velocity', 0.5)
self.arm_home_torque = rospy.get_param('~arm_home_torque', 0.4)
self.arm_start_torque = rospy.get_param('~arm_start_torque', 0.9)
self.arm_up_torque = rospy.get_param('~arm_up_torque', 0.6)
self.arm_up_standoff = rospy.get_param('~arm_up_standoff', 0.1)
#if arm position greater than this after heading down, we are too high for grabbing
self.arm_down_maximum = rospy.get_param('~arm_down_maximum', 3.0)
self.hand_open_position = rospy.get_param('~hand_open_position', 0.0)
self.grip_torque = 0.5
self.wrist_zero_position = rospy.get_param('~wrist_zero_position', 0.0)
# wait for all the dynamixel services to actually come live.
rospy.loginfo('Waiting for manipulator/wrist_joint services...')
rospy.wait_for_service('wrist_joint/go_to_position')
rospy.loginfo('Waiting for manipulator/arm_joint services...')
rospy.wait_for_service('arm_joint/go_to_position')
rospy.loginfo('Waiting for manipulator/hand_joint services...')
rospy.wait_for_service('hand_joint/go_to_position')
self.carousel_client = actionlib.SimpleActionClient('select_carousel_bin', SelectCarouselBinAction)
# make service proxies important services
self.arm_velocity_standoff = rospy.ServiceProxy('arm_joint/velocity_standoff', VelocityStandoff)
self.wrist_go_to_position = rospy.ServiceProxy('wrist_joint/go_to_position', GoToPosition)
self.hand_go_to_position = rospy.ServiceProxy('hand_joint/go_to_position', GoToPosition)
self.arm_pause = rospy.ServiceProxy('arm_joint/pause', Enable)
self.wrist_pause = rospy.ServiceProxy('wrist_joint/pause', Enable)
self.hand_pause = rospy.ServiceProxy('hand_joint/pause', Enable)
rospy.Subscriber('arm_joint/state',
JointState,
self.arm_joint_cb,
queue_size = 1 )
#IMPORTANT - actions and services (including pause) will be
#started after state machine declaration
#create the state machine!
self.sm = smach.StateMachine(
outcomes=['success', 'aborted', 'preempted'],
input_keys = ['action_goal'],
output_keys = ['action_result']
)
self.sm.userdata.arm_down_maximum = self.arm_down_maximum
with self.sm:
smach.StateMachine.add('START_MANIPULATOR',
manipulator_states.ProcessGoal(),
transitions = {'grab': 'ROTATE_WRIST',
'home': 'HOME_ARM',
'preempted' : 'PAUSED',
'aborted':'ERROR'}
)
@smach.cb_interface()
def manipulator_response_cb(userdata, response):
return response.result
@smach.cb_interface(input_keys=['wrist_angle'])
def wrist_angle_cb(userdata, request):
return GoToPositionRequest(self.wrist_zero_position + userdata.wrist_angle)
smach.StateMachine.add('ROTATE_WRIST',
smach_ros.ServiceState('wrist_joint/go_to_position', GoToPosition,
request_cb = wrist_angle_cb,
response_cb = manipulator_response_cb,
input_keys = ['wrist_angle']),
transitions = {'succeeded':'ARM_DOWN',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
@smach.cb_interface(input_keys = ['arm_down_maximum',
'arm_joint_position'],
output_keys = ['target_bin'],
outcomes = ['too_high'])
def arm_down_response_cb(userdata, response):
rospy.loginfo("MANIPULATOR ARM DOWN position: {!s}, limit: {!s}".format(userdata.arm_joint_position,
userdata.arm_down_maximum))
if userdata.arm_joint_position > userdata.arm_down_maximum:
#don't give up and try to grab anyway, just report the info
rospy.loginfo('MANIPULATOR did not get below arm_down_maximum, grabbing sample anyway')
return 'too_high'
else:
return 'succeeded'
smach.StateMachine.add('ARM_DOWN',
smach_ros.ServiceState('arm_joint/velocity_standoff', VelocityStandoff,
request = VelocityStandoffRequest(velocity = self.arm_down_velocity,
start_torque_limit = self.arm_down_torque,
torque_limit = self.arm_down_torque,
distance = self.arm_down_standoff,
check_velocity = False),
response_cb = arm_down_response_cb),
transitions = {'succeeded':'GRIP_SAMPLE',
'too_high':'GRIP_SAMPLE',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
@smach.cb_interface(input_keys=['grip_torque'])
def grip_torque_cb(userdata, request):
return TorqueHoldRequest(-1 * userdata.grip_torque)
smach.StateMachine.add('GRIP_SAMPLE',
smach_ros.ServiceState('hand_joint/torque_hold', TorqueHold,
request_cb = grip_torque_cb,
response_cb = manipulator_response_cb,
input_keys = ['grip_torque']),
transitions = {'succeeded':'ARM_UP',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
@smach.cb_interface(outcomes = ['timeout'])
def arm_up_response_cb(userdata, response):
return response.result
smach.StateMachine.add('ARM_UP',
smach_ros.ServiceState('arm_joint/velocity_standoff', VelocityStandoff,
request = VelocityStandoffRequest(velocity = self.arm_up_velocity,
start_torque_limit = self.arm_start_torque,
torque_limit = self.arm_up_torque,
distance = self.arm_up_standoff,
check_velocity = True),
response_cb = arm_up_response_cb),
transitions = {'succeeded':'GET_BIN',
'timeout':'RELEASE_GRIP',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
smach.StateMachine.add('ZERO_WRIST',
smach_ros.ServiceState('wrist_joint/go_to_position', GoToPosition,
request = GoToPositionRequest(self.wrist_zero_position),
response_cb = manipulator_response_cb),
transitions = {'succeeded':'success',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
@smach.cb_interface(input_keys=['target_bin'])
def get_carousel_bin_cb(userdata, request):
goal = SelectCarouselBinGoal()
goal.bin_index = userdata.target_bin
return goal
#carousel bin is acquired from datastore via callback method
smach.StateMachine.add('GET_BIN',
smach_ros.SimpleActionState('select_carousel_bin',
SelectCarouselBinAction,
goal_cb=get_carousel_bin_cb,
input_keys = ['target_bin']),
transitions = {'succeeded':'OPEN_HAND',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
smach.StateMachine.add('OPEN_HAND',
smach_ros.ServiceState('hand_joint/go_to_position', GoToPosition,
request = GoToPositionRequest(self.hand_open_position),
response_cb = manipulator_response_cb),
transitions = {'succeeded':'CLEAR_CAROUSEL',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
#return carousel to bin 0
#this is always the last state before a successful state machine execution
carousel_clear_bin = SelectCarouselBinGoal()
carousel_clear_bin.bin_index = 0
smach.StateMachine.add('CLEAR_CAROUSEL',
smach_ros.SimpleActionState('select_carousel_bin',
SelectCarouselBinAction,
goal=carousel_clear_bin,
output_keys=['action_result']),
transitions = {'succeeded':'ZERO_WRIST',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
smach.StateMachine.add('PAUSED',
manipulator_states.PausedState(self.pauseCV),
transitions ={'aborted':'aborted',
'preempted':'preempted', #during a home action, return preempted immediately
'succeeded':'HOME_ARM'} #during a grab action, home after unpause
)
smach.StateMachine.add('HOME_ARM',
smach_ros.ServiceState('arm_joint/velocity_standoff', VelocityStandoff,
request = VelocityStandoffRequest(velocity = self.arm_up_velocity,
start_torque_limit = self.arm_home_torque,
torque_limit = self.arm_home_torque,
distance = self.arm_up_standoff,
check_velocity = False),
response_cb = manipulator_response_cb,
input_keys = ['error','goal']),
transitions = {'succeeded':'HOME_WRIST',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
smach.StateMachine.add('HOME_WRIST',
smach_ros.ServiceState('wrist_joint/go_to_position', GoToPosition,
request = GoToPositionRequest(self.wrist_zero_position),
response_cb = manipulator_response_cb),
transitions = {'succeeded':'HOME_HAND',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
smach.StateMachine.add('HOME_HAND',
smach_ros.ServiceState('hand_joint/go_to_position', GoToPosition,
request = GoToPositionRequest(self.hand_open_position),
response_cb = manipulator_response_cb),
transitions = {'succeeded':'CLEAR_CAROUSEL',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
smach.StateMachine.add('RELEASE_GRIP',
smach_ros.ServiceState('hand_joint/go_to_position', GoToPosition,
request = GoToPositionRequest(self.hand_open_position),
response_cb = manipulator_response_cb),
transitions = {'succeeded':'ARM_UP',
'preempted':'PAUSED',
'aborted':'ERROR'}
)
smach.StateMachine.add('ERROR',
manipulator_states.ErrorState(),
transitions = {'error':'aborted'}
)
#now that the state machine is fully defined, make the action server wrapper
manipulator_action_server = smach_ros.ActionServerWrapper(
'grab_action', ManipulatorAction,
wrapped_container = self.sm,
succeeded_outcomes = ['success'],
aborted_outcomes = ['aborted'],
preempted_outcomes = ['preempted'],
goal_key = 'action_goal',
result_key = 'action_result'
)
sls = smach_ros.IntrospectionServer('smach_grab_introspection',
self.sm,
'/START_MANIPULATOR')
sls.start()
#subscribe to arm_joint state
rospy.Subscriber('arm_joint/state',
JointState,
self.arm_joint_cb,
queue_size = 1 )
#start action servers and services
manipulator_action_server.run_server()
self.pause_service = rospy.Service('pause', Enable, self.service_pause)
def get_carousel_bin_cb(userdata, request): goal = SelectCarouselBinGoal() goal.bin_index = userdata.target_bin return goal
