LANE_CENTERING_ASSIST_ENABLED
What it is
Enable or disable Lane Centering Assist (LCA).
Set true to enable LCA and false to disable LCA. When LCA is enabled, the ADAS system in the vehicle should be turned on and waiting for an activation signal from the driver. Once the feature is activated, the ADAS system should be steering the vehicle to keep it centered in its current lane.
This is different from Lane Keep Assist (LKA) which monitors if the driver unintentionally drifts toward or over the lane marking. If an unintentional lane departure is detected, the system applies steering control to return the vehicle into the current lane.
In general, LANE_CENTERING_ASSIST_ENABLED should always return true or false. If the feature is not available due to some temporary state, such as the vehicle speed being too low or too high, that information must be conveyed through the ErrorState values in the LANE_CENTERING_ASSIST_STATE property.
This property is defined as VehiclePropertyAccess.READ_WRITE, but OEMs have the option to implement it as VehiclePropertyAccess.READ only.
How the ID is built
A property ID is a 32-bit value packing four fields. Reading 0x1120100a apart:
| Field | Mask | Value | Means |
|---|---|---|---|
| Group | 0xf0000000 | 0x10000000 | SYSTEM |
| Area | 0x0f000000 | 0x01000000 | GLOBAL |
| Type | 0x00ff0000 | 0x00200000 | BOOLEAN |
| Ordinal | 0x0000ffff | 0x0000100a | 0x100a |
Reading it from an app
CarPropertyManager mgr = (CarPropertyManager)
car.getCarManager(Car.PROPERTY_SERVICE);
boolean value =
mgr.getBooleanProperty(VehiclePropertyIds.LANE_CENTERING_ASSIST_ENABLED, 0);This property can be read and written, though an OEM may implement it as read-only. It fires a callback whenever the value changes.