VEHICLE_PASSIVE_SUSPENSION_HEIGHT
What it is
Vehicle Passive Suspension Height in mm.
This property must communicate the real-time suspension displacement of the vehicle relative to its neutral position, given in mm. In other words, the displacement of the suspension at any given point in time relative to the suspension's position when the vehicle is on a flat surface with no passengers or cargo. When the suspension is compressed in comparison to the neutral position, the value should be negative. When the suspension is decompressed in comparison to the neutral position, the value should be positive.
Examples for further clarity: 1) Suppose the user is driving on a smooth flat surface, and all wheels are currently compressed by 2 cm in comparison to the default suspension height. In this scenario, this property must be set to -20 for all wheels. 2) Suppose the user drives over a pothole. While the front left wheel is over the pothole, it's decompressed by 3 cm in comparison to the rest of the wheels, or 1 cm in comparison to the default suspension height. All the others are still compressed by 2 cm. In this scenario, this property must be set to -20 for all wheels except for the front left, which must be set to 10.
HasSupportedValueInfo.hasMinSupportedValue and HasSupportedValueInfo.hasMaxSupportedValue must be true for all areas.
MinMaxSupportedValueResult.minSupportedValue represents the lower bound of the suspension height for the wheel at the specified area ID.
MinMaxSupportedValueResult.maxSupportedValue represents the upper bound of the suspension height for the wheel at the specified area ID.
How the ID is built
A property ID is a 32-bit value packing four fields. Reading 0x17400313 apart:
| Field | Mask | Value | Means |
|---|---|---|---|
| Group | 0xf0000000 | 0x10000000 | SYSTEM |
| Area | 0x0f000000 | 0x07000000 | WHEEL |
| Type | 0x00ff0000 | 0x00400000 | INT32 |
| Ordinal | 0x0000ffff | 0x00000313 | 0x313 |
Reading it from an app
CarPropertyManager mgr = (CarPropertyManager)
car.getCarManager(Car.PROPERTY_SERVICE);
mgr.registerCallback(callback,
VehiclePropertyIds.VEHICLE_PASSIVE_SUSPENSION_HEIGHT,
CarPropertyManager.SENSOR_RATE_ONCHANGE);This property is read-only — writes are rejected. It changes continuously, so subscribe at a sample rate rather than polling.