manipulation.constraint_graph_factory.GraphFactoryAbstract Class Reference

An abstract class which is loops over the different (gripper, handle) associations. More...

Inheritance diagram for manipulation.constraint_graph_factory.GraphFactoryAbstract:

Collaboration diagram for manipulation.constraint_graph_factory.GraphFactoryAbstract:

Public Member Functions
def	__init__ (self)
Main API
def	setGrippers (self, grippers)
def	setObjects (self, objects, handlesPerObjects, contactsPerObjects)
def	environmentContacts (self, envContacts)
def	setRules (self, rules)
	Set the function graspIsAllowed. More...
def	generate (self)
	Go through the combinatorial defined by the grippers and handles and create the states and transitions. More...
Abstract methods of the algorithm
def	makeState (self, grasps, priority)
	Create a new state. More...
def	makeLoopTransition (self, state)
	Create a loop transition. More...
def	transitionIsAllowed (self, stateFrom, stateTo)
	Check whether a transition between two states is allowed. More...
def	makeTransition (self, stateFrom, stateTo, ig)
	Create two transitions between two different states. More...

Public Attributes
	graspIsAllowed
	Reduces the problem combinatorial. More...
Internal variables
	states
	transitions
	handles
	the handle names More...
	grippers
	the gripper names More...
	envContacts
	the names of contact on the environment More...
	objects
	the object names More...
	handlesPerObjects
	See setObjects. More...
	objectFromHandle
	See setObjects. More...
	contactsPerObjects
	See setObjects. More...

Detailed Description

An abstract class which is loops over the different (gripper, handle) associations.

The behaviour can be tuned by setting the callback functions:

• graspIsAllowed (redundant with setRules)
• Algorithm steps

Sketch of the algorithm

Let

• be the set of grippers,
• be the set of handles.

A grasp is defined as a pair .

Each state (excluding waypoint states) is defined by a set of grasps. Given a set of grasps, we define

• available grippers as the grippers that are not the first element of any pair of the set of grasps,
• available handles as the handles that are not the second element of any pair of the set of grasps.

The first node is defined by the empty set. The graph is built recursiveley as follows:

if the set of grasps defining the node is not allowed (method graspIsAllowed ), return.

Otherwise, for any pair of available grippers and available handles,

• build a new state by adding grasp to the current set of grasps (method makeState),
• build a transition from the current state to the new state (method makeTransition )
• build a loopTransition from the current state to itself (method makeLoopTransition )
• repeat the two above states to the new state.

Constructor & Destructor Documentation

__init__()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.__init__

(

self

)

Member Function Documentation

environmentContacts()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.environmentContacts	(		self,
			envContacts
	)

Parameters

envContacts

contact on the environment to be considered.

generate()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.generate

(

self

)

Go through the combinatorial defined by the grippers and handles and create the states and transitions.

makeLoopTransition()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.makeLoopTransition	(		self,
			state
	)

Create a loop transition.

Parameters

state

an object returned by makeState which represent the state

makeState()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.makeState	(		self,
			grasps,
			priority
	)

Create a new state.

Parameters

grasps	a handle index for each gripper, as in GraphFactoryAbstract.graspIsAllowed.
priority	the state priority.

Returns

an object representing the state.

makeTransition()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.makeTransition	(		self,
			stateFrom,
			stateTo,
			ig
	)

Create two transitions between two different states.

Parameters

stateFrom	same as grasps in makeState
stateTo	same as grasps in makeState
ig	index if the grasp vector that changes, i.e. such that

setGrippers()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.setGrippers	(		self,
			grippers
	)

Parameters

grippers

list of gripper names to be considered

setObjects()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.setObjects	(		self,
			objects,
			handlesPerObjects,
			contactsPerObjects
	)

Parameters

objects	list of object names to be considered
handlesPerObjects	a list of list of handle names.
contactsPerObjects	a list of list of contact names. handlesPerObjects and contactsPerObjects must have one list for each object, in the same order.

setRules()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.setRules	(		self,
			rules
	)

Set the function graspIsAllowed.

Parameters

rules

a list of Rule objects

transitionIsAllowed()

def manipulation.constraint_graph_factory.GraphFactoryAbstract.transitionIsAllowed	(		self,
			stateFrom,
			stateTo
	)

Check whether a transition between two states is allowed.

Parameters

stateFrom,stateTo

states to connect

Member Data Documentation

contactsPerObjects

manipulation.constraint_graph_factory.GraphFactoryAbstract.contactsPerObjects

See setObjects.

envContacts

manipulation.constraint_graph_factory.GraphFactoryAbstract.envContacts

the names of contact on the environment

graspIsAllowed

manipulation.constraint_graph_factory.GraphFactoryAbstract.graspIsAllowed

Reduces the problem combinatorial.

Function called to check whether a grasps is allowed. It takes as input a list of handle indices (or None) such that i-th grippers grasps grasps[i]-th handles. It must return a boolean

It defaults to:

lambda x : True 

grippers

manipulation.constraint_graph_factory.GraphFactoryAbstract.grippers

the gripper names

handles

manipulation.constraint_graph_factory.GraphFactoryAbstract.handles

the handle names

handlesPerObjects

manipulation.constraint_graph_factory.GraphFactoryAbstract.handlesPerObjects

See setObjects.

objectFromHandle

manipulation.constraint_graph_factory.GraphFactoryAbstract.objectFromHandle

See setObjects.

objects

manipulation.constraint_graph_factory.GraphFactoryAbstract.objects

the object names

states

manipulation.constraint_graph_factory.GraphFactoryAbstract.states

transitions

manipulation.constraint_graph_factory.GraphFactoryAbstract.transitions

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

• src/hpp/corbaserver/manipulation/constraint_graph_factory.py