Package org.robwork.sdurw_invkin

Class 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.

    Usage example:
    // create a inverse kinematics solver for your dvs. here we use ResolvedRateSolver ResolvedRateSolver iksolver(&myDevice); // takes a pointer to your device // if we want colision free ik results then create or get the collisiondetector CollisionDetector *detector = NULL; // here we don't care about collisions // now create the meta solver IKMetaSolver mSolver(&iksolver, &myDevice, detector); // the pose that you want the endeffector to be in Transform3D<> pose(Vector3D<>(0,0,1),RPY<>(1,0,0)); // and use it to generate joint configurations std::vector<Q> result; result = mSolver.solve( pose , state, 200, true );

    • Constructor Detail

      • IKMetaSolver

        public IKMetaSolver​(long cPtr,
                    boolean cMemoryOwn)

      • IKMetaSolver

        public IKMetaSolver​(IterativeIKPtr iksolver,
                    DevicePtr device,
                    SWIGTYPE_p_rw__core__PtrT_rw__proximity__CollisionDetector_t collisionDetector)
        Constructs IKMetaSolver

        The IKMetaSolver takes ownership of the iksolver. The IKMetaSolver
        does NOT take ownership of the collisionDetector. To skip testing for
        collision use null as collision detector

        Parameters:
        iksolver - [in] The basic iksolver to use. Ownership is taken
        device - [in] Device to solve for

        collisionDetector - [in] CollisionDetector to use. If null no
        collision detection used.

      • IKMetaSolver

        public IKMetaSolver​(IterativeIKPtr iksolver,
                    DevicePtr device)
        Constructs IKMetaSolver

        The IKMetaSolver takes ownership of the iksolver. The IKMetaSolver
        does NOT take ownership of the collisionDetector. To skip testing for
        collision use null as collision detector

        Parameters:
        iksolver - [in] The basic iksolver to use. Ownership is taken
        device - [in] Device to solve for

      • IKMetaSolver

        public IKMetaSolver​(IterativeIKPtr iksolver,
                    DevicePtr device,
                    SWIGTYPE_p_rw__core__PtrT_rw__pathplanning__QConstraint_t constraint)
        Constructs IKMetaSolver

        The IKMetaSolver takes ownership of the iksolver. To skip testing for
        feasibility set constraint to NULL.

        Parameters:
        iksolver - [in] The basic iksolver to use. Ownership is taken
        device - [in] Device to solve for

        constraint - [in] QConstraint pointer to use. If null no
        constraints is applied

    • Method Detail

      • getCPtr

        public static long getCPtr​(IKMetaSolver obj)

      • solve

        public VectorQ solve​(Transform3D baseTend,
                     State state)


        Searches for a valid solution using the parameters set in the IKMetaSolver
        Overrides:
        solve in class InvKinSolver
        Parameters:
        baseTend - [in] Desired base to end transformation \robabx{}{desired}{\mathbf{T}}

        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.

      • 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)
        Description copied from class: InvKinSolver
        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​(Transform3D 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.

      • getTCP

        public FrameCPtr getTCP()
        Description copied from class: InvKinSolver
        Returns the Tool Center Point (TCP) used when solving the IK problem.

        Overrides:
        getTCP in class InvKinSolver
        Returns:
        The TCP Frame used when solving the IK.