# Overview

We designed Stretch's hardware to be easily extended. You can make your own tool and attach it to the wrist to creatively expand what Stretch can do. Your tool can also use Dynamixel X-series servos from Robotis via the provided TTL bus.

In this tutorial, we provide examples of some of the tools that we've created. We've released them with a permissive Apache 2.0 license, so you're free to use them as you wish. We hope they'll inspire you to create your own.

We also include URDF and mesh files for many of the tools in their stretch_description folder. See the Stretch ROS documentation for guidance on integrating these tools into your robot model.

We'd love it if you shared your creations with the community. We recommend you create a GitHub repository for your own tools and then post an announcement to the forum to let people know about it. 

|                             Tool                             |             Description                                      |
| :----------------------------------------------------------: | :----------------------------------------------------------: |
|             Puller                                           |        Attachment to pull drawers, handles or push buttons   |
|             Dry Erase Holder                                 |        Compliant attachment for drawing on white-boards      |
|             DexWrist                                         |        A 3-DoF upgrade for the standard gripper              |
|             Updating URDF                                    |        Updating the URDF after changing a tool               |

## Licenses

The contents in this tutorial that represent parts of the Stretch robot, such as its head, arm, wrist, and default gripper, are covered by the [CC BY-NC-SA 4.0](https://creativecommons.org/licenses/by-nc-sa/4.0/) license. Please note that the Stretch robot and its default gripper are also covered by pending patents. Please see the robot license for details. 

Other contents in this tutorial created by Hello Robot Inc. that specifically pertain to the tools that attach to Stretch as accessories are covered by the [Apache 2.0](http://www.apache.org/licenses/LICENSE-2.0) license. Please see the tool license for details.

The contents of this tutorial are intended for use with the Stretch mobile manipulator, which is a robot produced and sold by Hello Robot Inc. For further information, including inquiries about dual licensing, please contact Hello Robot Inc.