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This page assumes knowledge of ROS.

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Configure your catkin workspace for custom messages
Before configuring a custom ROS message, you'll have to provide the Formant agent with the path to your catkin workspace. For more information, see Environment variables for the Formant Agent.

This guide will teach you how to ingest ROS topic data directly into Formant.

Step 1: Create the ROS topic stream

In Formant, in the upper-left corner, open the menu and click Settings.
Click Devices, and then click on the device you want to configure.
Click the Telemetry tab, and then click Add Stream.
Click ROS Topic. This will open the New ROS Topic Stream configuration window:

Property	Usage
Telemetry stream name	Give the stream a name.
On demand	If ON, this stream will store data locally on your device, and only upload data to Formant when you click Retrieve on-demand data. `Rate limit` controls the rate at which datapoints are added to the on-device buffer. For more information, see On demand streams. If OFF, this stream will ingest periodically. `Rate limit` controls the rate of data ingestion.
Video encoding	Only applicable for `sensor_msgs/Image` and `sensor_msgs/CompressedImage` streams. Choose whether you want images ingested on this stream to be encoded as a video.
Validation schema	Only applicable for JSON and text streams. Choose a configuration schema for this stream.
Ingestion topic	Enter the ROS topic name, starting with `/`. The text field will auto-populate with ROS topics detected on your device.
ROS message path (optional)	Give the path into the ROS message to the data you want, in `field.arr[x][y]` format. This can be as complex as necessary, e.g., `field.arr[x][y].subfield.arr2[i]`.
Add tags (e.g. `key: value`) (optional)	Add tags to each datapoint of this stream. For more information on tags, see Configure access levels.
Rate limit (Hz) (optional)	If `On demand` is ON: Set the rate at which data is added to the on-device buffer. Data in the on-device buffer will be ingested by the agent when you click Retrieve on-demand data. For more information, see On demand streams. If `On demand` is OFF: Set the rate at which data is ingested. The default rate is 0.5 Hz.

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You can use the Add ROS Topic button to combine data from multiple topics into a single stream.

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Supported formats for streaming video using sensor_msgs/Image messages
For a sensor_msgs/Image topic to be a valid input to Formant's automatic video encoding, it must have a value for the encoding field that matches one of the following exactly:

rgb8

rgba8

bgr8

bgra8

mono8

mono16

8UC1

yuv422

If your encoding value is unsupported, you may be able to adjust the encoding field of the sensor_msgs/Image message without changing the underlying data. In some cases, you will need to transform both the data and the encoding property to supported values.
If you have trouble with this, please contact our Customer Success team via the Intercom messenger in the bottom-right corner of this page, or via email at [email protected].

When you're finished configuring your stream, click Done, and then Save. Finally, Save your device settings.

Step 2: Add stream to a view

Once you've added a stream to your device, your next step is to add it to a view in Formant.

Add the streams you want to visualize, and then move on to Viewing data in Formant.

ROS topic type vs. Formant data type

The table below shows a mapping from ROS topic type to Formant datapoint type:

ROS message type	Formant datapoint type
`std_msgs/String` `std_msgs/Char`	Text
`std_msgs/UInt8` `std_msgs/UInt16` `std_msgs/UInt32` `std_msgs/UInt64` `std_msgs/Int8` `std_msgs/Int16` `std_msgs/Int32` `std_msgs/Int64` `std_msgs/Float32` `std_msgs/Float64`	Numeric
`std_msgs/Bool`	Bitset
`sensor_msgs/NavSatFix`	Location
`sensor_msgs/BatteryState`	Battery
`sensor_msgs/Image` `sensor_msgs/CompressedImage` (with `Video encoding` set to OFF)	Image
`sensor_msgs/Image` `sensor_msgs/CompressedImage` (with `Video encoding` set to ON)	Video
`sensor_msgs/PointCloud2` `sensor_msgs/LaserScan`	Point cloud
All other ROS types (including custom messages)	JSON

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If you notice an issue with this page or need help, please reach out to us! Use the 'Did this page help you?' buttons below, or get in contact with our Customer Success team via the Intercom messenger in the bottom-right corner of this page, or at [email protected].