.. toctree::
   :glob:

Rover Telemetry UI: MQTT Client UI for Rover
#############################################

.. image:: ../roverstatic/images/rovertelemetry_logo.png
   :width: 50%
   :align: center
   :alt: ../roverstatic/images/rovertelemetry_logo.png

Description
^^^^^^^^^^^^^
Rover Telemetry UI (**rover-telemetry-ui**) is designed to communicate with multi-agent rovers using MQTT protocol over cloud.
It is built with node.js as a web application and it is used for reactive MQTT communication.
Rover Telemery UI is shown below:

.. image:: ../roverstatic/images/rovertelemetryui_screen.png
   :width: 100%
   :align: center
   :alt: ../roverstatic/images/rovertelemetryui_screen.png


Operation
^^^^^^^^^^^^^
Upon connection, rover-telemetry-ui subscribes to topic ``rover/<roverID>/telemetry``, which is redirected from ``telemetry`` topic on the Eclipse Hono side.

.. image:: ../roverstatic/images/cloudinfra1.png
   :width: 100%
   :align: center
   :alt: ../roverstatic/images/cloudinfra1.png

``telemetry`` topic retrieves sensor and core usage information in following format:

.. code-block:: javascript
   :linenos:

	{
		"gy521":{
			"accel":{
				"x":-1,
				"y":-1,
				"z":-1
			},
			"angle":{
				"x":-35.264389038085938,
				"y":-35.264389038085938,
				"z":-54.735610961914062
			},
			"gyro":{
				"x":-1,
				"y":-1,
				"z":-1
			}
		},
		"hmc5883l":{
			"bearing":47.366317749023438
		},
		"infrared":{
			"frontleft":100.0,
			"frontright":100.0,
			"rearleft":100.0,
			"rearright":100.0
		},
		"ultrasonic":{
			"front":0.0,
			"rear":0.0
		},
		"cores":{
			"core0":55.099998474121094,
			"core1":100.0,
			"core2":100.0,
			"core3":18.899999618530273
		}
	}

If connected, driving buttons can be used to send telemetry data to rover. This message is published to ``rover/<roverID>/RoverDriving/control`` topic in the following format:

.. code-block:: javascript
   :linenos:

   {
		"mode":<int mode>,
		"command":<char command>,
		"speed":<int speed>
   }

``"speed"`` entry is an integer value between 360 (lowest speed) and 480 (highest speed) for the rover.

``"command"`` entry indicates many integrated functions, such as the ones listed below:

* F → Stop Movement
* Q → Go Forward-Left
* W → Go Forward
* E → Go Forward-Right
* A → Go Backward-Left
* S → Go Backward
* D → Go Backward-Right
* J → Turn Left On Spot
* K → Turn Right On Spot
* R → Shutdown Rover

In rover-telemetry-ui only ``"mode":0`` is supported, which indicated manual driving.

Using rover-telemetry-ui
^^^^^^^^^^^^^^^^^^^^^^^^^^
.. note:: Project is hosted in the repository: `https://github.com/app4mc-rover/rover-telemetry-ui.git <https://github.com/app4mc-rover/rover-telemetry-ui.git>`_.

To download:

.. code-block:: javascript
   :linenos:

   git clone https://github.com/app4mc-rover/rover-telemetry-ui.git

To download dependencies (If you don't have node.js installed, first install node.js):

.. code-block:: javascript
   :linenos:

   cd rover-telemetry-ui
   sudo npm install net connect serve-static http socket.io express path mqtt

To run the server:

.. code-block:: javascript
   :linenos:

   cd scripts/
   sudo node start_rovertelemetryui.js

Finally, go to your web browser and find the page at ``http://<your host address>:5055/rovertelemetryui.html``.