Gauges

Last validated: 2026-05-05

Use gauges when the operator needs live vehicle state in the control page. Examples include speed, battery, hydraulic pressure, drive mode, autonomy state, or warnings from the vehicle controller.

Preferred portal/widget flow

In the portal-based operator experience, gauges should be configured as widgets on the operator page. The vehicle integration sends telemetry through OCP, and the operator page binds widget values to fields in that telemetry payload.

Typical flow:

  1. Decide which vehicle telemetry field should be visible.

  2. Add the value to vehicle_user_data.user_data in the vehicle-side OCP response.

  3. In the portal, add a gauge or indicator widget.

  4. Bind the widget to the telemetry field.

  5. Test with the real vehicle or a simulator.

For example, the vehicle-side response can include:

{
  "ack_time": 123456,
  "ack_time_mac": 987654321,
  "vehicle_user_data": {
    "user_data": {
      "speed_mps": 1.4,
      "battery": 0.82,
      "drive_mode": "manual"
    }
  }
}

Webview fallback

If you are building a custom webview instead of using portal widgets, listen for ocp_vehicle_user_data and render the values in your page.

See Operator-Side Control and Webview and JavaScript SDK.

Design notes

Show operator-critical values with clear units and stale-data behavior. OCP repeats the latest vehicle data, so dashboards should use ms_since_last_vehicle_data when they need to warn about stale telemetry.