# Gripper

The Stretch Compliant Gripper utilizes a Dynamixel XL430-W250-T servo to drive the spring grasper mechanism. The kinematics of the grasper mechanism is complex and non-linear relative to the motor position.  As shown, it includes mounting features on one side to allow for the attachment of simple rigid tools such as [hooks and pullers](https://github.com/hello-robot/stretch_tool_share/tree/master/tool_share/puller_v1). 

![image alt text](https://raw.githubusercontent.com/hello-robot/stretch_hardware_guides/master/docs/images/re2/gripper.png)

<table>
  <tr>
    <td></td>
    <td>Item</td>
    <td>Notes</td>
  </tr>
  <tr>
    <td>A</td>
    <td>Stud attachment</td>
    <td>Threaded 6-32</td>
  </tr>
  <tr>
    <td>B</td>
    <td>Thread attahcment</td>
    <td>Threaded M4</td>
  </tr>
</table>

The attachment features are spaced at 9 mm.

The weight of the Stretch Compliant Gripper is 240 g.

## Gripper Removal

Here we describe removing the Stretch Compliant gripper. Installation is simply these steps in reverse.

1. Unplug the Dynamixel cable from the back of the gripper. 
2. Remove the 4 screws holding the gripper to the bracket.
3. Remove the gripper from the mounting bracket
4. Unscrew the 8 screws holding the mounting bracket to the bottom of the tool plate.

![image alt text](https://raw.githubusercontent.com/hello-robot/stretch_hardware_guides/master/docs/images/re2/gripper_mount_b_rs.png)

![image alt text](https://raw.githubusercontent.com/hello-robot/stretch_hardware_guides/master/docs/images/re2/gripper_mount_a_rs.png)