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Path Planning ("World View") 
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Once the robot configuration is complete and all ROS nodes have been successfully launched (indicated by a green **GO** with a check mark at the top bar), path planning can begin. To do this, switch to the planning view by clicking on the blue-highlighted **Xamla** symbol and selecting the menu item **World View**. A 3D view opens showing the configured robot  along with an **interactive marker** (movable coordinate system) at the **tool center point** (TCP) of the robot. Use the left mouse button to move and rotate the interactive marker. As a result, a semitransparent **ghost** of the robot will appear and follow the movements of the interactive marker. When the desired target pose is reached with the ghost, click on the **Plan** button at the top bar and a white path from the start pose to the target pose will appear (see Fig. 4.1). 

.. figure:: images/World_View.png

   Figure 4.1  World view with path planning for robot arm UR5.

.. note:: Path planning can only be performed if the current robot configuration has been compiled and all ROS nodes have been successfully started (displayed by a green **GO** with check mark in the top bar)!

After clicking on the **Execute** field, the robot moves along the displayed path to the target pose (ghost and actual robot merge). If instead you click on the **Reset ghost** button, the ghost is moved back to the current pose of the robot.
The ghost serves as preview of ​​the target configuration of the robot. This allows to identify and avoid collisions in advance. Instead of directly moving the ghost, you can also move an **additional interactive marker** to a target pose. Thereto, double click into the scene and a second interactive marker will appear. Move this marker to the desired pose, click with the right mouse button into the scene and select the item **Move Ghost To Pose Picker**.

Next to the **Plan** button at the top bar, the path planner can be selected from a list (currently **MoveIt!** or **TVP**). **TVP** stands for **Trapezoidal Velocity Profile**, which is particularly suitable for time-critical problems without obstacles in the working area of ​​the robot. **MoveIt!** is a complex motion planning framework with collision check (i.e. self-collision as well as collision with obstacles in the scene) and based on the open motion planning library 
`OMPL <http://ompl.kavrakilab.org/>`_ .
Furthermore you can select the **Move group** and the **End effector** at the top bar, which especially becomes interesting with several robot arms.

By right-clicking in the scene, the current joint values and pose of the robot, as well as a current joint trajectory and Cartesian path can be saved. Moreover, as mentioned before, the ghost can be moved to the second interactive marker (called **pose picker**), **collision objects** can be added to the scene and the active cursor (i.e. the currently chosen interactive marker) can be rotated.
Saved joint values, poses, joint trajectories and collision objects appear in a list displayed on the left side of the **World View**. If you click on one of these saved elements, more detailed information about the selected element (e.g. names and values ​​for the joints) appears on the right of the **World View**. When selecting stored joint values, moreover the ghost automatically moves to the corresponding location.

.. note:: To save the stored joint values and poses **permanently**, the **World View** has to be saved by pressing the **Save** button at the top bar. Thereby, the joint values and poses are written to the project folder into **db/worldview.json**.