> ## Documentation Index
> Fetch the complete documentation index at: https://bedrockdynamics.studio/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Connect to a Robot

> Stream live data from a robot or simulator

Substrate can connect to any robot, drone, or simulator that exposes data over a Foxglove WebSocket or ROS 2 bridge. Once connected, live topics stream directly into the IDE where you can visualize them in 3D viewers, telemetry plots, and the topic browser.

## Establishing a Connection

<Steps>
  <Step title="Verify your robot or simulator is running">
    Ensure your robot (or simulator) is powered on and publishing data. For ROS 2 systems, a Foxglove WebSocket bridge must be running on the target machine. For Gazebo simulations managed by Substrate, this is handled automatically.

    Common bridge setups:

    ```bash theme={null}
    # ROS 2 Foxglove Bridge
    ros2 launch foxglove_bridge foxglove_bridge_launch.xml

    # Verify topics are being published
    ros2 topic list
    ```
  </Step>

  <Step title="Open the connection dialog">
    Open the Command Palette with `Cmd+P` (macOS) or `Ctrl+P` (Windows/Linux) and search for **"Connect to Robot"**. Select it to open the connection dialog.
  </Step>

  <Step title="Enter the WebSocket URL">
    In the connection dialog, enter the WebSocket URL of your robot or bridge. Common defaults:

    | Source                   | URL                               |
    | ------------------------ | --------------------------------- |
    | Foxglove Bridge (local)  | `ws://localhost:8765`             |
    | Foxglove Bridge (remote) | `ws://<robot-ip>:8765`            |
    | Custom endpoint          | Any valid `ws://` or `wss://` URL |
  </Step>

  <Step title="Connect and verify">
    Click **Connect**. Once the handshake completes, available topics appear in the **Topic Browser** panel on the left sidebar. Each topic shows its message type and current publish rate.
  </Step>

  <Step title="Add topics to panels">
    Drag any topic from the Topic Browser into a panel:

    * Drop onto a **Plot** panel to chart scalar or vector data over time.
    * Drop onto a **Viewer3D** panel to render 3D markers, point clouds, or TF frames.
    * Drop onto the **Log View** panel to stream text-based log messages.

    Multiple panels can subscribe to the same topic simultaneously.
  </Step>
</Steps>

<Tip>
  For live Gazebo simulations launched from Substrate, the connection is automatic. The simulation bridge establishes a gRPC stream to the proxy as soon as the simulation container starts, and topics appear in the Topic Browser without any manual configuration.
</Tip>

## Connection Status

The connection indicator in the status bar shows the current state:

* **Green** -- Connected and receiving data.
* **Yellow** -- Connected but no data received in the last 5 seconds.
* **Red** -- Disconnected or connection failed.

Click the indicator to open the connection dialog and reconnect or change the target URL.

<Warning>
  If connecting to a robot on a different network, verify that firewall rules allow WebSocket traffic on the target port. The default Foxglove Bridge port is 8765.
</Warning>