# /vehicle/status/gear\_status

## Specifications

| Item | Value |
| --- | --- |
| Last Updated | 2026-01-21 |
| Interface Type | topic |
| Interface Name | /vehicle/status/gear\_status |
| Data Type | [autoware\_vehicle\_msgs/msg/GearReport](<https://github.com/autowarefoundation/autoware_msgs/blob/main/autoware_vehicle_msgs/msg/GearReport.msg>) |
| Rate \[Hz\] | 10 or N/A |
| QoS Reliability | reliable |
| QoS Durability | volatile |
| QoS Depth | 1 |

## Description

Get the current gear status of the vehicle. The statuses are listed in the table below.

The [`autoware_component_interface_specs`](<https://github.com/autowarefoundation/autoware_core/blob/1.10.0/common/autoware_component_interface_specs/include/autoware/component_interface_specs/vehicle.hpp>) package defines this topic with `volatile` durability. The vehicle interface publishes this topic. Known publishers, for example [`pacmod_interface`](<https://github.com/tier4/pacmod_interface/blob/main/pacmod_interface/src/pacmod_interface/pacmod_interface.cpp>) and [`autoware_simple_planning_simulator`](<https://github.com/autowarefoundation/autoware_simple_planning_simulator/blob/1.1.0/autoware_simple_planning_simulator/src/simple_planning_simulator/simple_planning_simulator_core.cpp>), publish the status continuously with `volatile` durability, not only when the status changes. The design intent is different: use `transient_local` durability and publish only when the status changes. Make sure that the publishers and the subscribers in your system use compatible QoS settings.

| Value | Description |
| --- | --- |
| PARK | The engine or motor is disconnected from the tires and the stopping mechanism is activated. |
| NEUTRAL | The engine or motor is disconnected from the tires. |
| DRIVE | The engine or motor is connected to the tires in the forward direction. |
| REVERSE | The engine or motor is connected to the tires in the backward direction. |

## Message

The `stamp` field is the status received time or hardware time such as VCU. In the case of periodic publication, use the latest time, not the last status change. For the `report` field, use the valid values listed above. The `NONE` value can be used internally by programs, but will never be sent as a topic. Values such as `LOW` and `DRIVE_2` can be used if the vehicle has its own special gear types, but a dedicated implementation is required to handle this.

## Errors

Unknown status: If the vehicle interface cannot get the status due to connection loss, etc., the status is stopped and a diagnostic error is reported.

Invalid status: If the vehicle interface receives an undefined status, stop publishing status and report as diagnostics.

Hardware Fault: If the vehicle platform reports a sensor fault, a diagnostic error is reported.

## Support

This interface is required. If the vehicle does not have gear, simulate the gear behavior.

## Limitations

Latency: Gear shifting is a mechanical process that takes time (typically 0.5s to 2.0s). The status reported here reflects the actual engaged gear, so there will be a delay after sending a command. Autoware must handle this transition period.

## Use cases

- Control the vehicle for autonomous driving.
- Display current gear status to the operator.

## Requirement

- Support getting the current gear status of the vehicle.
- Support vehicle-specific gear status if necessary.

## Design

- Support four typical gear types: PARK, NEUTRAL, DRIVE, and REVERSE.
- Unused values can be used for special gear types.
- Simulate gear if necessary to increase reusability.

## History

| Date | Description |
| --- | --- |
| 2026-01-21 | First release in the new format. |