Electrical Plug Mating Plugin

Overview

Underwater electrical lead connection is a common task performed by UUV. A video of this task being performed can be found here.
The uuv_mating_plugin plugin in the uuv_mating package provides the mating/unmating functionality.

Getting Started

To get started with a world with a socket and a plug to connect please run the following command. roslaunch uuv_dave uuv_dave_electrical_mate.launch.
The following gazebo world will open up.
In this world there is a plug and a socket. Using the UUV's manipulator arm, the plug can be carried over and inserted into the socket. The two pictures below show the plug and the socket.

A video that demonstrates the functionality of this plugin can be found here.

Under the hood

There are three states for the plug as represented by the following diagram.

Free state

When the plug is not close to the socket, it is in the free state and is not physically bound to socket. The plug transitions from this state to the joined state when it is aligned with the socket and is within close proximity.

Joined state

When the plug is in this state, it is bound to the socket with a prismatic joint. The plug can be pushed towards the the socket. Once enough force is applied to the socket from the plug, the plug goes into the the fixed state.

Fixed state

When the plug is in this state, it is fixed to the socket and all of it's degrees of freedoms are locket. To release the plug from the socket, a pulling force on the plug must be applied using the UUV's manipulator arm's fingers. Once enough force is applied, the plug goes into the free state.

Limitation

1. The current plugin is not designed to support multiple plugs and sockets.
2. To go from the Fixed to Free state, the force that needs to be applied from the plug needs to come from a link that contains the name finger_tips.

Future Improvements

1. Allow for more than one plug/socket, to be functional in this world.