Description

This process allows users to generate OpenRAVE inverse kinematics solvers for any robot manipulator. The manipulator's arm joints are used for obtaining the joints to solve for. The user can specify the IK type (Rotation, Translation, Full 6D, Ray 4D, etc), the free joints of the kinematics, and the accuracy. For example, generating the right arm 6D IK for the PR2 robot where the free joint is the first joint and the free increment is 0.01 radians is:

openrave.py --database inversekinematics --robot=robots/pr2-beta-static.robot.xml --manipname=rightarm  --freejoint=r_shoulder_pan_joint --freeinc=0.01

Generating the 3d rotation IK for the stage below is:

openrave.py --database inversekinematics --robot=robots/rotation_stage.robot.xml --rotation3donly

../../images/databases_inversekinematics_rotation_stage.jpg

Generating the ray inverse kinematics for the 4 degrees of freedom barrett wam is:

openrave.py --database inversekinematics --robot=drill.robot.xml --ray4donly

Testing

Every IK solver should be tested with the robot using --iktests=XXX. However, calling inversekinematics will always re-generate the IK, even if one already exists. In order to just run tests, it is possible to specify the --usecached option to prevent re-generation and specifically test:

openrave.py --database inversekinematics --robot=robots/barrettwam.robot.xml --usecached --iktests=100

This will give the success rate along with information whether the IK gives a wrong results or fails to find a solution.

If there are a lot of free joints in the IK solver, then their discretization can greatly affect whether solutions are found or not. In this case, it is advisable to reduce the discretization threshold by using the --freeinc option.

run(*args, **kwargs)

source code

Executes the inversekinematics database generation, args specifies a list of the arguments to the script.

Help

Usage: openrave.py --database inversekinematics [options]

Computes the closed-form inverse kinematics equations of a robot manipulator,
generates a C++ file, and compiles this file into a shared object which can
then be loaded by OpenRAVE

Options:
  -h, --help            show this help message and exit
  --freejoint=FREEJOINTS
                        Optional joint name specifying a free parameter of the
                        manipulator. If nothing specified, assumes all joints
                        not solving for are free parameters. Can be specified
                        multiple times for multiple free parameters.
  --precision=PRECISION
                        The precision to compute the inverse kinematics in,
                        (default=10).
  --accuracy=ACCURACY   The small number that will be recognized as a zero
                        used to eliminate floating point errors
                        (default=1e-07).
  --usecached           If set, will always try to use the cached ik c++ file,
                        instead of generating a new one.
  --rotation3donly      [deprecated] If true, need to specify only 3 solve
                        joints and will solve for a target rotation
  --direction3donly     [deprecated] If true, need to specify only 2 solve
                        joints and will solve for a target direction
  --translation3donly   [deprecated] If true, need to specify only 3 solve
                        joints and will solve for a target translation
  --ray4donly           [deprecated] If true, need to specify only 4 solve
                        joints and will solve for a target ray
  --usedummyjoints      Treat the unspecified joints in the kinematic chain as
                        dummy and set them to 0. If not specified, treats all
                        unspecified joints as free parameters.
  --freeinc=FREEINC     The discretization value of freejoints.
  --numiktests=IKTESTS, --iktests=IKTESTS
                        Will test the ik solver and return the success rate.
                        IKTESTS can be an integer to specify number of random
                        tests, it can also be a filename to specify the joint
                        values of the manipulator to test. The formst of the
                        filename is #numiktests [dof values]*
  --perftiming=PERFTIMING
                        Number of IK calls for measuring the internal ikfast
                        solver.
  --outputlang=OUTPUTLANG
                        If specified, will output the generated code in that
                        language (ie --outputlang=cpp).
  --iktype=IKTYPE       The ik type to build the solver current types are:
                        Transform6D, Rotation3D, Translation3D, Direction3D,
                        Ray4D

  OpenRAVE Environment Options:
    --collision=COLLISION
                        Default collision checker to use
    --physics=PHYSICS   Default physics engine to use
    -d DEBUG, --debug=DEBUG
                        Debug level

  OpenRAVE Database Generator General Options:
    --show              Graphically shows the built model
    --getfilename       If set, will return the final database filename where
                        all data is stored
    --gethas            If set, will exit with 0 if datafile is generated and
                        up to date, otherwise will return a 1. This will
                        require loading the model and checking versions, so
                        might be a little slow.
    --robot=ROBOT       OpenRAVE robot to load
                        (default=robots/barrettsegway.robot.xml)
    --manipname=MANIPNAME
                        The name of the manipulator on the robot to use

Module inversekinematics

Usage

Description

Testing

Loading from C++

run(*args, **kwargs)

Classes
	InverseKinematicsModel Generates analytical inverse-kinematics solutions, compiles them into a shared object/DLL, and sets the robot's iksolver. Only generates the models for the robot's active manipulator. To generate IK models for each manipulator in the robot, mulitple InverseKinematicsModel classes have to be created.

Variables
	__package__ = `'openravepy.databases'`