.. Comment: this file is automatically generated by `update_example_docs.py`.
   It should not be modified manually.

Mobile IK
==========================================


Same as 01_basic_ik.py, but with a mobile base!

All examples can be run by first cloning the PyRoki repository, which includes the ``pyroki_snippets`` implementation details.



.. code-block:: python
        :linenos:


        import time
        import viser
        from robot_descriptions.loaders.yourdfpy import load_robot_description
        import numpy as np

        import pyroki as pk
        from viser.extras import ViserUrdf
        import pyroki_snippets as pks


        def main():
            """Main function for IK with a mobile base.
            The base is fixed along the xy plane, and is biased towards being at the origin.
            """

            urdf = load_robot_description("fetch_description")
            target_link_name = "gripper_link"

            # Create robot.
            robot = pk.Robot.from_urdf(urdf)

            # Set up visualizer.
            server = viser.ViserServer()
            server.scene.add_grid("/ground", width=2, height=2)
            base_frame = server.scene.add_frame("/base", show_axes=False)
            urdf_vis = ViserUrdf(server, urdf, root_node_name="/base")

            # Create interactive controller with initial position.
            ik_target = server.scene.add_transform_controls(
                "/ik_target", scale=0.2, position=(0.61, 0.0, 0.56), wxyz=(0, 0.707, 0, -0.707)
            )
            timing_handle = server.gui.add_number("Elapsed (ms)", 0.001, disabled=True)

            cfg = np.array(robot.joint_var_cls(0).default_factory())

            while True:
                # Solve IK.
                start_time = time.time()
                base_pos, base_wxyz, cfg = pks.solve_ik_with_base(
                    robot=robot,
                    target_link_name=target_link_name,
                    target_position=np.array(ik_target.position),
                    target_wxyz=np.array(ik_target.wxyz),
                    fix_base_position=(False, False, True),  # Only free along xy plane.
                    fix_base_orientation=(True, True, False),  # Free along z-axis rotation.
                    prev_pos=base_frame.position,
                    prev_wxyz=base_frame.wxyz,
                    prev_cfg=cfg,
                )

                # Update timing handle.
                elapsed_time = time.time() - start_time
                timing_handle.value = 0.99 * timing_handle.value + 0.01 * (elapsed_time * 1000)

                # Update visualizer.
                urdf_vis.update_cfg(cfg)
                base_frame.position = np.array(base_pos)
                base_frame.wxyz = np.array(base_wxyz)


        if __name__ == "__main__":
            main()