Definition
Functional Requirements
Syntax
Semantics
Conformance Testing
Performance Assessment
1 Definition
CAV State is a Data Type generated by the Autonomous Motion Subsystem (AMS) that describes the operational condition of the CAV at a specific Time and Position. It is derived from measurements, estimations, and assessments performed inside the CAV using onboard sensing, diagnostics, and monitoring functions.
2 Functional Requirements
A CAV State shall include the following information:
- Time and Position of CAV State generation.
- Battery State, including temperature overload, remaining capacity, and abnormal discharge indicators.
- Brake Responsiveness, based on effective deceleration relative to the reference performance defined in UNECE braking regulations.
- Motor Responsiveness, based on effective acceleration derived from available motor torque, gear ratio, wheel radius, and vehicle mass.
- Wheel Responsiveness, describing traction effectiveness, slip behaviour, rotational anomalies, and mechanical integrity.
The AMS uses CAV State to estimate operational time and distance by combining CAV State with Route, lighting configuration, air conditioning load, cabin temperature, and Velocity.
3 Syntax
https://schemas.mpai.community/CAV2/V1.1/data/CAVState.json
4 Semantics
| Header | CAV State Header – Standard “CAV‑CST‑Vx.y”. |
| MInstanceID | Identifier of the M-Instance (Virtual Space) associated with this CAV State. |
| UEnvironmentID | Identifier of the U-Environment (Real Space) associated with this CAV State. |
| CAVStateID | Unique identifier of this CAV State instance. |
| CAVStateTime | Time this CAV State was produced. |
| CAVStateSpaceTime | Space/Time where/when this CAV State was generated. |
| CAVState | Set of data describing the operational condition of the CAV. |
| – BatteryState | Battery condition including capacity, temperature, and abnormal discharge indicators. |
| – MeasureType | Unit of battery capacity measurement: “mAh” or “Wh”. |
| – Value | Battery capacity value in the specified MeasureType. |
| – Percentage | Remaining battery capacity as a percentage. |
| – BrakeResponsiveness | Brake performance based on effective deceleration relative to UNECE braking regulations. |
| – MeasuredDeceleration | Measured vehicle deceleration (m/s²). |
| – ExpectedDeceleration | Expected deceleration per UNECE reference (m/s²). |
| – Delta | Difference between measured and expected deceleration (m/s²). |
| – UNECEReferenceUsed | Identifier of the UNECE braking regulation used as reference. |
| – MotorResponsiveness | Effective acceleration derived from available motor torque, gear ratio, wheel radius, and vehicle mass. |
| – MeasuredAcceleration | Measured vehicle acceleration (m/s²). |
| – ExpectedAcceleration | Expected vehicle acceleration (m/s²). |
| – MotorTorque | Available motor torque (N·m). |
| – GearRatio | Current gear ratio. |
| – WheelRadius | Wheel radius (m). |
| – VehicleMass | Vehicle mass (kg). |
| – WheelResponsiveness | Traction effectiveness, slip behaviour, rotational anomalies, and mechanical integrity. |
| – SlipRatio | Wheel slip ratio derived from wheel-speed sensors. |
| – RotationalAnomaly | Indicates whether a rotational anomaly is detected. |
| – MechanicalStatus | Description of wheel mechanical integrity status. |
| DataXMData | MPAI-PTF Data Exchange Metadata providing provenance, authorisation, legal, security, and confidence information associated with this CAV State in a trusted data exchange context. |
| DescrMetadata | Human-readable descriptive metadata of the CAV State (plain text, max 2048 characters). |
5 Conformance Testing
A Data instance conforms with CAV State (CAV‑CVS) if:
- The Data validates against the CAV State’s JSON Schema.
- All Data in the CAV State’s JSON Schema:
- Have the specified type.
- Validate against their JSON Schemas.
- Conform with their Data Qualifiers.
6 Performance Assessment
Not part of this specification.
