# Pincer Attachment

### Using platform2 pincer attachment

In order to use the pincer attachment, you must have a way publish to the servo motor.

![image](https://user-images.githubusercontent.com/47371441/236552674-41450e72-5fad-4752-8a4d-e8debf7c2a85.png)

### Publisher

First, you must import Bool. True will be to open the attachment, and False will be to close the attachment.

`from std_msgs.msg import Bool`

The following publisher needs to be published to:

`rospy.Publisher('/servo', Bool, queue_size=1)`

By publishing to the servo motor, you are telling it to either open or close. If you publish True, the pincer will open. If you publish False, the pincer will close.

```
def open():
    self.pub.publish(Bool(True))

def close():
    self.pub.publish(Bool(False))
```

This has use beyond this pincer itself. By having any custom attachment with a servo motor, this provides an easy way to publish to it.

### Full example of the pincer class

```
#!/usr/bin/env python3

import rospy
from std_msgs.msg import Bool

class Pincer:
    """ Allows pincer to open and close """

    def __init__(self):
        self.pub = rospy.Publisher('/servo', Bool, queue_size=1)

    def open(self):
        self.pub.publish(Bool(True))

    def close(self):
        self.pub.publish(Bool(False))
```


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