Collision Configurations
========================

A **collision configuration** sets how strictly the server checks for
collisions: a **margin** (the minimum allowed distance between parts) and a
list of **excluded pairs** (parts allowed to touch, such as a tool and the part
it is working on).

.. important::

   Only the configuration named ``default`` is used: by the collision check
   when you pose a robot (:doc:`targets`) and by PTP planning
   (:doc:`ptp_trajectories`). Other configurations are saved but not used.

Open the editor with **☰** (**More setup**) → **Collision Configs**. The
table lists each configuration's **Name**, **Margin (m)** and number of
**Pairs**. ``default`` is marked **(active)**.

Create a configuration
----------------------

Click **Create Config**, enter a **Name** and click **Create Config** again.
New configurations start with a margin of 0 and no excluded pairs.

Use a name that is not already taken. Creating a configuration with an
existing name, including ``default``, replaces it with an empty one: its
margin and excluded pairs are lost.

Edit a configuration
--------------------

Click **Edit** in the configuration's row.

* **Collision Margin (m)**: enter the margin and click **Save**.
* **Excluded Pairs**: choose **Component 1** and **Component 2** from the
  lists of collision parts in the workcell, and click **Add Pair**. Click
  **Remove** on a row to check that pair again.

.. warning::

   Composer Studio overwrites the margin of ``default``, keeping its excluded
   pairs:

   * adding a system or a scene object sets it to 0;
   * creating a PTP trajectory sets it to that trajectory's **Collision
     Margin**, 0 by default (:doc:`ptp_trajectories`).

   Check the margin of ``default`` after these steps and set it again if
   needed.

.. figure:: _static/images/collision_configs.png
   :width: 60%
   :alt: The default configuration, with the sander and its adapter allowed to touch the part.

   The default configuration, with the sander and its adapter allowed to touch the part.

Rename or delete a configuration
--------------------------------

Use **Rename** or **Delete** in the configuration's row. Composer Studio warns
before you rename or delete ``default``: afterwards, collision checks run with
an empty configuration (no margin, no excluded pairs) until a new ``default``
exists. Adding a system or a scene object, or creating a PTP trajectory,
creates a new empty ``default`` automatically.