Package org.robwork.sdurw

Class IKMetaSolver

java.lang.Object

org.robwork.sdurw.InvKinSolver

org.robwork.sdurw.IterativeIK

org.robwork.sdurw.IKMetaSolver

public class IKMetaSolver
extends IterativeIK

Solve the inverse kinematics problem with respect to joint limits and
collisions.

Given an arbitrary iterative inverse kinematics solver, the IKMetaSolver
attempts to find a collision free solution satisfying joint limits. It
repeatingly calls the iterative solver with new random start configurations
until either a solution is found or a specified max attempts has been
reached.

Constructor Summary

Constructors

Constructor	Description
IKMetaSolver(long cPtr, boolean cMemoryOwn)

Method Summary

Modifier and Type	Method	Description
void	delete()
static long	getCPtr(IKMetaSolver obj)
void	setCheckJointLimits(boolean check)	Specifies whether to check joint limits before returning a solution.
void	setMaxAttempts(long maxAttempts)	Sets up the maximal number of attempts
void	setProximityLimit(double limit)	Sets the distance for which two solutions are considered the same. For distance measure an infinite norm is used.
void	setStopAtFirst(boolean stopAtFirst)	Sets whether to stop searching after the first solution
VectorQ	solve(Transform3Dd baseTend, State state)	Calculates the inverse kinematics Given a desired transformation and the current state, the method solves the inverse kinematics problem.
VectorQ	solve(Transform3Dd baseTend, State state, long cnt, boolean stopatfirst)	Solves the inverse kinematics problem Tries to solve the inverse kinematics problem using the iterative inverse kinematics solver provided in the constructor.

Methods inherited from class org.robwork.sdurw.IterativeIK

getCPtr, getMaxError, getMaxIterations, getProperties, makeDefault, setMaxError, setMaxIterations

Methods inherited from class org.robwork.sdurw.InvKinSolver

getCPtr, getTCP

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

IKMetaSolver

public IKMetaSolver(long cPtr,
                    boolean cMemoryOwn)

Method Detail

getCPtr

public static long getCPtr(IKMetaSolver obj)

delete

public void delete()

Overrides:

delete in class IterativeIK

solve

public VectorQ solve(Transform3Dd baseTend,
                     State state)

Calculates the inverse kinematics

Given a desired transformation
and the current state, the method solves the inverse kinematics
problem.

If the algorithm is able to identify multiple solutions (e.g. elbow
up and down) it will return all of these. Before returning a solution,
they may be checked to be within the bounds of the configuration space.
(See setCheckJointLimits(bool) )

Overrides:

solve in class InvKinSolver

Parameters:

baseTend - [in] Desired base to end transformation.

state - [in] State of the device from which to start the
iterations

Returns:

List of solutions. Notice that the list may be empty.

Note: The targets baseTend must be defined relative to the base of the
robot/device.

Searches for a valid solution using the parameters set in the IKMetaSolver

setMaxAttempts

public void setMaxAttempts(long maxAttempts)

Sets up the maximal number of attempts

Parameters:

maxAttempts - [in] Maximal number of attempts

setStopAtFirst

public void setStopAtFirst(boolean stopAtFirst)

Sets whether to stop searching after the first solution

Parameters:

stopAtFirst - [in] True to stop after first solution has been found

setProximityLimit

public void setProximityLimit(double limit)

Sets the distance for which two solutions are considered the same.

For distance measure an infinite norm is used. Default value is set to 1e-5.

Set limit < 0 to allow doublets in the solution.

Parameters:

limit - [in] The proximity limit.

setCheckJointLimits

public void setCheckJointLimits(boolean check)

Specifies whether to check joint limits before returning a solution.

Overrides:

setCheckJointLimits in class InvKinSolver

Parameters:

check - [in] If true the method should perform a check that joints are within bounds.

solve

public VectorQ solve(Transform3Dd baseTend,
                     State state,
                     long cnt,
                     boolean stopatfirst)

Solves the inverse kinematics problem

Tries to solve the inverse kinematics problem using the iterative
inverse kinematics solver provided in the constructor. It tries at
most cnt times and can either be stopped after the first solution
is found or continue to search for solutions. If multiple solutions
are returned there might be duplicates in the list.

Parameters:

baseTend - [in] Desired base to end transform

state - [in] State of the workcell

cnt - [in] Maximal number of attempts

stopatfirst - [in] If true the method will return after the first
solution is found. If false it will continue searching for more solution
until the maximal number of attemps is met.