Goal

Through this guide, you will learn to connect to the robot via WebRTC, in order to exploit the following features:

live bidirectional audio
live video feed from the robot
ROS bridge over the data channel

The pieces

Three packages from the robot software will be used:

madmux the video server
yawl the WebRTC library
gizmo_webrtc the high-level application implementing signaling, the ROS bridge and various connection lifecycle hookups

A few key concepts

WebRTC

WebRTC is an open standard for real-time communication for browsers and other mobile applications. It is supported by most modern browsers, such as Firefox and Chrome.

The standard defines protocols and APIs to establish peer-to-peer connections, potentially through an intermediary.

Signaling

In order for a WebRTC connection to be established between two peers, a third-party communication mechanism is needed to exchange the needed pieces of information needed by each peer to connect to the other. This is called signaling.

On the robot, there are two signaling mechanisms:

flubnub: a websocket-based local-network-only signaling
mqtt: an authenticated pub/sub mechanism using AWS IoT

Tutorial: using a web browser to connect to my Kuri

The following steps have to be run from a development environment connected to the same network as Kuri. The following has been tested with recent versions of Firefox and Chrome.

checkout the code:

git clone https://github.com/KuriRobot/kuri-documentation

run the local server

cd kuri-documentation/examples/webrtc
python3 -m http.server

open a browser window and point it to http://localhost:8000
get the UUID of your robot by running the following command on the robot
```
roboversion
```
enter the hostname and the robot UUID in the webpage and click the Join button
you should see what the robot sees, and a text box will appear

Extra steps: the rosbridge protocol

The text box that appeared enables you to send commands and receive responses to and from the robot via the rosbridge protocol.