hrl_pr2_arms.ep_arm_base.EPArmBase Class Reference

Base class for interacting with a realtime controller using an equilibrium point control frame work. More...

Inheritance diagram for hrl_pr2_arms.ep_arm_base.EPArmBase:

List of all members.

Public Member Functions
def	__init__
	Constructor.
def	get_controller_state
	Returns the current state of the realtime controller.
def	get_end_effector_pose
	Returns the current pose of the tooltip.
def	get_ep
	Returns the current equilibrium point as read from the controller.
def	is_ep_stale
	Returns whether the equilibrium point has been recorded for some time.
def	set_ep
	Commands the arm to move to desired equilbrium point.
def	wait_for_ep
	Wait until we have the ep from the controller.
Public Attributes
	arm_side
	controller_name
	ctrl_state_dict
	ctrl_state_lock
	ep
	ep_lock
	ep_time
Private Member Functions
def	_save_ep
	Method to be implemented by subclasses to record the equilibrium point.

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Detailed Description

Base class for interacting with a realtime controller using an equilibrium point control frame work.

An equilibrium point is a set of parameters representing the state of the controller at which no torques would be applied. For a PID controller, this represents the joint angles where the error would be zero.

Definition at line 51 of file ep_arm_base.py.

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Constructor & Destructor Documentation

def hrl_pr2_arms.ep_arm_base.EPArmBase.__init__	(		self,
			arm_side,
			urdf,
			base_link,
			end_link,
			controller_name = None,
			kdl_tree = None,
			timeout = 1.
	)

Constructor.

Parameters:

arm_side	Used to signify side of robot for similar arms (e.g. 'r' for right, 'l' for left)
urdf	URDF object of robot.
base_link	Name of the root link of the kinematic chain. Will fill in arm_side if s is in string.
end_link	Name of the end link of the kinematic chain. Will fill in arm_side if s is in string.
controller_name	Optional name of the controller which will be subscribed to to obtain controller information
kdl_tree	Optional KDL.Tree object to use. If None, one will be generated from the URDF.
timeout	Time in seconds to wait for the /joint_states topic.

Definition at line 66 of file ep_arm_base.py.

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Member Function Documentation

def hrl_pr2_arms.ep_arm_base.EPArmBase._save_ep	(		self,
			ep
	)		[private]

Method to be implemented by subclasses to record the equilibrium point.

Definition at line 143 of file ep_arm_base.py.

def hrl_pr2_arms.ep_arm_base.EPArmBase.get_controller_state

(

self

)

Returns the current state of the realtime controller.

The state is filled in by the subclasses.

Returns:

dict with realtime controller information.

Definition at line 120 of file ep_arm_base.py.

def hrl_pr2_arms.ep_arm_base.EPArmBase.get_end_effector_pose

(

self

)

Returns the current pose of the tooltip.

Returns:

4x4 np.mat homogeneous matrix

Definition at line 86 of file ep_arm_base.py.

def hrl_pr2_arms.ep_arm_base.EPArmBase.get_ep

(

self

)

Returns the current equilibrium point as read from the controller.

Returns:

equilibrium point

Definition at line 92 of file ep_arm_base.py.

def hrl_pr2_arms.ep_arm_base.EPArmBase.is_ep_stale	(		self,
			stale_time = 1.
	)

Returns whether the equilibrium point has been recorded for some time.

Parameters:

stale_time

Time in seconds to pass to consider the EP stale.

Returns:

True if the EP is stale.

Definition at line 134 of file ep_arm_base.py.

def hrl_pr2_arms.ep_arm_base.EPArmBase.set_ep	(		self,
			args
	)

Commands the arm to move to desired equilbrium point.

Definition at line 100 of file ep_arm_base.py.

def hrl_pr2_arms.ep_arm_base.EPArmBase.wait_for_ep	(		self,
			timeout = 1.
	)

Wait until we have the ep from the controller.

Parameters:

timeout

Time in seconds at which we break if we haven't recieved the EP.

Definition at line 106 of file ep_arm_base.py.

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Member Data Documentation

hrl_pr2_arms::ep_arm_base.EPArmBase::arm_side

Definition at line 66 of file ep_arm_base.py.

hrl_pr2_arms::ep_arm_base.EPArmBase::controller_name

Definition at line 66 of file ep_arm_base.py.

hrl_pr2_arms::ep_arm_base.EPArmBase::ctrl_state_dict

Definition at line 66 of file ep_arm_base.py.

hrl_pr2_arms::ep_arm_base.EPArmBase::ctrl_state_lock

Definition at line 66 of file ep_arm_base.py.

hrl_pr2_arms::ep_arm_base.EPArmBase::ep

Definition at line 66 of file ep_arm_base.py.

hrl_pr2_arms::ep_arm_base.EPArmBase::ep_lock

Definition at line 66 of file ep_arm_base.py.

hrl_pr2_arms::ep_arm_base.EPArmBase::ep_time

Definition at line 66 of file ep_arm_base.py.

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The documentation for this class was generated from the following file:

• ep_arm_base.py