Definition
Functional Requirements
Syntax
Semantics
Conformance
Performance
1 Definition
Spatial Data is a Data Type produced by the Motion Actuation Subsystem that describes the Spatial Attitude of the Connected Autonomous Vehicle (CAV). It captures positional evolution, motion intensity, and inclination of the CAV in relation to its environment, enabling downstream AIMs to interpret movement, acceleration, and orientation consistently.
2 Functional Requirements
Spatial Data shall represent the following five measurements:
- Odometer Data: scalar expressed in metres (m).
- Speedometer Data: scalar expressed in metres/second (m/s).
- Accelerometer Data: scalar expressed in metres/second/second (m/s²).
- Inclinometer Data: vector of CAV inclination in the direction of travel and perpendicular to it, in degrees (°).
- Gyroscope Data: rate at which the CAV turns about the vertical axis (yaw rate) and, optionally, about the lateral and longitudinal axes, in degrees/second (°/s).
In CAV-TEC V2.0 the Motion Actuation Subsystem turns the heading of the CAV by the gyroscope: its Spatial Attitude comes from the sensors of motion only, not from what the steered wheels report.
3 Syntax
https://schemas.mpai.community/CAV2/V2.0/data/SpatialData.json
4 Semantics
Table 1 specifies the semantics of the Spatial Data Data Type.
| Label | Type | Req. | Description |
|---|---|---|---|
| Header | string (CAV-SPD-V2.0) | Yes | Spatial Data Header – Standard CAV-SPD-Vx.y. |
| SpatialDataID | string | Yes | Unique identifier of this Spatial Data instance. |
| SpaceTime | Simple Time | Yes | Spatial Attitude and Time of this Spatial Data instance. |
| SpatialData | object | Yes | Set of Spatial Data measurements. |
| SpatialData. |
number | Yes | Distance travelled by the CAV, expressed in metres (m). |
| SpatialData. |
number | Yes | Speed of the CAV, expressed in metres/second (m/s). |
| SpatialData. |
number | Yes | Acceleration of the CAV, expressed in metres/second/second (m/s²). |
| SpatialData. |
object | Yes | Inclination of the CAV in the direction of travel and perpendicular to it, in degrees (°). |
| SpatialData. |
number | Yes | CAV inclination in the direction of travel, in degrees (°). |
| SpatialData. |
number | Yes | CAV inclination perpendicular to the direction of travel, in degrees (°). |
| SpatialData. |
object | Yes | Rate at which the CAV turns about its axes, in degrees/second (°/s), positive anticlockwise. |
| SpatialData. |
number | Yes | Rate of turn about the vertical axis, in degrees/second (°/s), positive to the left. |
| SpatialData. |
number | Rate of turn about the lateral axis, in degrees/second (°/s). | |
| SpatialData. |
number | Rate of turn about the longitudinal axis, in degrees/second (°/s). | |
| DataXMData | Data Exchange Metadata | MPAI-PTF Data Exchange Metadata providing provenance, authorisation, legal, security, and confidence information associated with this Spatial Data instance in a trusted data exchange context. | |
| DescrMetadata | string | Human-readable descriptive metadata of the Spatial Data instance (plain text, max 2048 characters). |
5 Conformance Testing
Data conform to the Spatial Data Data Type when they validate against its schema. If the schema references other schemas, data referencing a secondary schema shall also validate against that schema, if present, and conform with the Qualifier, if present.
