pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper Class Reference

reactive/guarded movement and grasping More...

Public Member Functions
def	__init__
def	adjust_grasp
	adjust the grasp in an attempt to center the object according to the contacts, if we appear to be in a marginal grasp assumes the fingers start closed around the object
def	broadcast_phase
	broadcast the current manipulation phase (of type ManipulationPhase)
def	check_fingers_in_table
	check to see if the fingers are colliding with the table in gripper_pose according to the collision model defaults to the current gripper pose
def	check_goal_reached
	check if we have gotten close enough to our goal along approach_vect (according to goal_pos_thres)
def	check_gripper_opening
	check the gripper opening to see if it's within our goal gripper opening range
def	check_guarded_move_contacts
	check for tip/side/back/palm contact
def	check_if_contacts_need_adjusting
	check for marginal grasps if we see only the edge sensors on both fingers, move in the z-axis direction if we see only the tip sensors, or front sensors not far enough in (and no palm sensors are pressed), move forward if we see only one edge on one finger and the opposite edge on the other finger, rotate the hand (disabled)
def	check_preempt
	check for a preempt (overload for your application)
def	close_hard
	close with a force of self.close_force, and record that the fingertips need a long-reset unless we're using the slip controller, in which case open and close to estimate stiffness
def	compliant_close
	close compliantly (controller manager should be in Cartesian mode) (if one finger touches first, counter-move the arm to keep that finger in-place while closing)
def	compute_approach_dir
	compute (unit) approach direction in base_link frame from an approach_pose and grasp_pose (returns scipy array)
def	compute_approach_vect
	compute approach vector in base_link frame from an approach_pose and grasp_pose (returns scipy array)
def	get_fingertip_readings_during_find_contact
	check the state of find_gripper_contact and try to collect the first positive thresholded fingertip readings only looks for front contacts
def	guarded_move_cartesian
	move the wrist to a desired Cartesian pose while watching the fingertip sensors settling_time is how long to wait after the controllers think we're there
def	guarded_move_ik
	move the wrist to a desired Cartesian pose using IK and watching the fingertip sensors
def	lift_carefully
	lift while checking for slip (assumes we already closed around the object) gripper_translation is a desired GripperTranslation for the lift slip servoing should continue after the lift (for moving the object through free space), until the gripper opens or closes returns 1 if the object is still in the hand at the end of the lift, 0 otherwise
def	make_orthogonal
def	move_cartesian_step
	move to a Cartesian pose goal
def	normalize_vect
def	open_and_reset_fingertips
	open the gripper, wait for the fingertips to release, and reset the thresholds if we're not touching anything
def	palm_touching
	are either of the palm sensors touching? (palm sensors removed; stubs left in just in case)
def	place_carefully
	place while checking for the gripper to report that the object has hit the table final_place_pose is a PoseStamped for the gripper in its desired place pose place_overshoot is the distance in m to go past the final_place_pose
def	ppmat
	pretty-print scipy matrix to string
def	reactive_approach
	reactive approach (stop if unexpected fingertip contact and go around) assumes we are already at the approach pose, going to grasp_pose along the direction approach_dir grasp_pose should be in base_link frame and have found and checked the joint-angle path side_step is how far to move right or left when you hit something num_tries is how many bump-and-moves to try before quitting
def	reactive_grasp
	do a reactive approach followed by a compliant close if the approach is successful then move forward more and try again along the approach if the gripper opening is not as expected succeeds if the gripper is closed with an opening between min_gripper_opening and max_gripper_opening tries the approach-and-grasp grasp_num_tries times (including the first approach) forward step is how far to move along the approach direction (past the goal) for the next approach-and-grasp try min_contact_row is how far in from the tip we require contact on the front of each sensor (farther in is okay), with values from 0-4 (-1 to ignore) possible return values: 0=success, 1=ran out of grasp tries, 2=ran out of approach tries, 3=aborted approach_pose, grasp_pose, joint_path, side_step, back_step, approach_num_tries, goal_pos_thres are inputs to the approach
def	return_rel_pose
	convert a relative vector in frame to a pose in the base_link frame if start_pose is not specified, uses current pose of the wrist if orthogonal_to_vect and orthogonal_to_vect_frame are specified, first convert vector to be orthogonal to orthogonal_to_vect
def	shake_object
	shake the object by rotating the wrist roll and flex joints and the arm pan joint at a particular set of arm angles
def	throw_exception
	throw an abort exception
def	vect_dot
def	vect_norm
def	vect_proj
Public Attributes
	close_force
	cm
	manipulation_phase_dict
	pressure_listener
	reactive_approach_result_dict
	reactive_grasp_result_dict
	using_slip_detection
	whicharm
Private Attributes
	_closed_hard
	_phase_pub
	_photo
	_table_name

Detailed Description

reactive/guarded movement and grasping

Definition at line 69 of file reactive_grasp.py.

Member Function Documentation

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::__init__	(	self,
		cm
	)

Definition at line 71 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::adjust_grasp	(	self,
		grasp_pose,
		initial_l_readings,
		initial_r_readings,
		z_step = `.015`,
		x_step = `.015`,
		min_gripper_opening = `.0021`,
		max_gripper_opening = `.1`,
		min_contact_row = `1`,
		num_tries = `4`
	)

adjust the grasp in an attempt to center the object according to the contacts, if we appear to be in a marginal grasp assumes the fingers start closed around the object

Definition at line 1106 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::broadcast_phase	(	self,
		phase
	)

broadcast the current manipulation phase (of type ManipulationPhase)

Definition at line 117 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::check_fingers_in_table	(	self,
		gripper_pose = `None`
	)

check to see if the fingers are colliding with the table in gripper_pose according to the collision model defaults to the current gripper pose

Definition at line 1072 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::check_goal_reached	(	self,
		approach_vect,
		goal_pos,
		goal_pos_thres
	)

check if we have gotten close enough to our goal along approach_vect (according to goal_pos_thres)

Definition at line 514 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::check_gripper_opening	(	self,
		min_gripper_opening = `.01`,
		max_gripper_opening = `.1`
	)

check the gripper opening to see if it's within our goal gripper opening range

Definition at line 818 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::check_guarded_move_contacts ( self )

check for tip/side/back/palm contact

Definition at line 329 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::check_if_contacts_need_adjusting	(	self,
		min_contact_row,
		l_readings = `None`,
		r_readings = `None`,
		check_table = `1`
	)

check for marginal grasps if we see only the edge sensors on both fingers, move in the z-axis direction if we see only the tip sensors, or front sensors not far enough in (and no palm sensors are pressed), move forward if we see only one edge on one finger and the opposite edge on the other finger, rotate the hand (disabled)

Definition at line 729 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::check_preempt ( self )

check for a preempt (overload for your application)

Definition at line 123 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::close_hard	(	self,
		force = `None`
	)

close with a force of self.close_force, and record that the fingertips need a long-reset unless we're using the slip controller, in which case open and close to estimate stiffness

Definition at line 1033 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::compliant_close ( self )

close compliantly (controller manager should be in Cartesian mode) (if one finger touches first, counter-move the arm to keep that finger in-place while closing)

Definition at line 213 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::compute_approach_dir	(	self,
		approach_pose,
		grasp_pose
	)

compute (unit) approach direction in base_link frame from an approach_pose and grasp_pose (returns scipy array)

Definition at line 532 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::compute_approach_vect	(	self,
		approach_pose,
		grasp_pose
	)

compute approach vector in base_link frame from an approach_pose and grasp_pose (returns scipy array)

Definition at line 539 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::get_fingertip_readings_during_find_contact	(	self,
		contacts_desired,
		timeout = `10.`
	)

check the state of find_gripper_contact and try to collect the first positive thresholded fingertip readings only looks for front contacts

Definition at line 134 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::guarded_move_cartesian	(	self,
		pose_stamped,
		timeout = `3.0`,
		settling_time = `0.5`
	)

move the wrist to a desired Cartesian pose while watching the fingertip sensors settling_time is how long to wait after the controllers think we're there

Definition at line 349 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::guarded_move_ik	(	self,
		pose_stamped,
		max_joint_vel = `.05`
	)

move the wrist to a desired Cartesian pose using IK and watching the fingertip sensors

Definition at line 400 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::lift_carefully	(	self,
		gripper_translation,
		min_gripper_opening = `.0021`,
		max_gripper_opening = `.1`,
		hardness_gain = `0.060`
	)

lift while checking for slip (assumes we already closed around the object) gripper_translation is a desired GripperTranslation for the lift slip servoing should continue after the lift (for moving the object through free space), until the gripper opens or closes returns 1 if the object is still in the hand at the end of the lift, 0 otherwise

Definition at line 833 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::make_orthogonal	(	self,
		vect1,
		vect2
	)

Definition at line 453 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::move_cartesian_step	(	self,
		pose,
		timeout = `10.0`,
		settling_time = `3.0`,
		blocking = `0`
	)

move to a Cartesian pose goal

Definition at line 317 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::normalize_vect	(	self,
		vect
	)

Definition at line 438 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::open_and_reset_fingertips	(	self,
		reset = `0`
	)

open the gripper, wait for the fingertips to release, and reset the thresholds if we're not touching anything

Definition at line 1045 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::palm_touching ( self )

are either of the palm sensors touching? (palm sensors removed; stubs left in just in case)

Definition at line 547 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::place_carefully	(	self,
		final_place_pose,
		place_overshoot,
		min_gripper_opening = `.0021`,
		max_gripper_opening = `.1`
	)

place while checking for the gripper to report that the object has hit the table final_place_pose is a PoseStamped for the gripper in its desired place pose place_overshoot is the distance in m to go past the final_place_pose

Definition at line 968 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::ppmat	(	self,
		mat
	)

pretty-print scipy matrix to string

Definition at line 808 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::reactive_approach	(	self,
		approach_dir,
		grasp_pose,
		joint_path = `None`,
		side_step = `.015`,
		back_step = `.03`,
		num_tries = `10`,
		goal_pos_thres = `0.01`
	)

reactive approach (stop if unexpected fingertip contact and go around) assumes we are already at the approach pose, going to grasp_pose along the direction approach_dir grasp_pose should be in base_link frame and have found and checked the joint-angle path side_step is how far to move right or left when you hit something num_tries is how many bump-and-moves to try before quitting

Definition at line 559 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::reactive_grasp	(	self,
		approach_pose,
		grasp_pose,
		joint_path = `None`,
		side_step = `.015`,
		back_step = `.03`,
		approach_num_tries = `10`,
		goal_pos_thres = `0.01`,
		min_gripper_opening = `0.0021`,
		max_gripper_opening = `0.1`,
		grasp_num_tries = `2`,
		forward_step = `0.03`,
		min_contact_row = `1`,
		object_name = `"points"`,
		table_name = `"table"`,
		grasp_adjust_x_step = `.02`,
		grasp_adjust_z_step = `.015`,
		grasp_adjust_num_tries = `3`
	)

do a reactive approach followed by a compliant close if the approach is successful then move forward more and try again along the approach if the gripper opening is not as expected succeeds if the gripper is closed with an opening between min_gripper_opening and max_gripper_opening tries the approach-and-grasp grasp_num_tries times (including the first approach) forward step is how far to move along the approach direction (past the goal) for the next approach-and-grasp try min_contact_row is how far in from the tip we require contact on the front of each sensor (farther in is okay), with values from 0-4 (-1 to ignore) possible return values: 0=success, 1=ran out of grasp tries, 2=ran out of approach tries, 3=aborted approach_pose, grasp_pose, joint_path, side_step, back_step, approach_num_tries, goal_pos_thres are inputs to the approach

Definition at line 1237 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::return_rel_pose	(	self,
		vector,
		frame,
		start_pose = `None`,
		orthogonal_to_vect = `None`,
		orthogonal_to_vect_frame = `'base_link'`
	)

convert a relative vector in frame to a pose in the base_link frame if start_pose is not specified, uses current pose of the wrist if orthogonal_to_vect and orthogonal_to_vect_frame are specified, first convert vector to be orthogonal to orthogonal_to_vect

Definition at line 465 of file reactive_grasp.py.

def pr2_gripper_reactive_approach::reactive_grasp::ReactiveGrasper::shake_object	(	self,
		arm_angles = `None`,
		min_gripper_opening = `.0021`,
		max_gripper_opening = `.1`,
		wrist_roll_shake_time = `0.5`,
		wrist_flex_shake_time = `0.5`,
		arm_pan_shake_time = `0.25`
	)