Go to CAV-TEC V1.1 Data Types

Definition
Functional Requirements
Syntax
Semantics
Conformance Testing
Performance Assessment

1      Definition

An Ego‑Remote AMS Message is a Message exchanged between the AMS of an Ego CAV and the AMS of a Remote CAV. It enables the Ego CAV to obtain the Remote CAV’s interpretation of a portion of its Environment corresponding to the Ego CAV’s intended U‑Location. The Message may contain:

  • A Request/Response relating to the M‑Location corresponding to the intended U‑Location.
  • The Trajectory the Ego CAV intends to adopt.

2      Functional Requirements

The interaction between Ego and Remote CAVs unfolds as follows:

  1. Request Phase – The Ego CAV sends an Ego‑Remote AMS Message requesting how the Remote CAV interprets a specific subset of its Environment corresponding to the intended U‑Location.
  2. Remote CAV Processing – Upon accepting the request, the Remote CAV:
    • Converts the requested U‑Location into the corresponding M‑Location in its Full Environment Descriptors (FED).
    • Extracts the FED subset corresponding to that M‑Location using its scene‑based object structure.
    • Adapts the level of detail to the bandwidth currently available.
    • Sends the M‑Location and the relevant FED subset to the Ego CAV.
  3. Ego CAV Processing – Upon receiving the Response, the Ego CAV:
    • Reconciles its own M‑Location understanding with the Remote CAV’s data.
    • Records major discrepancies between its own Positions and those inferred from the Remote FED.

CAV‑TEC V1.1 does not address any privacy requirements related to hiding the identity of the CAV providing information from its Full Environment Descriptors.

3      Syntax

https://schemas.mpai.community/CAV2/V1.1/data/EgoRemoteAMSMessage.json

4      Semantics

Table 1 – Semantics of the Ego‑Remote AMS Message Data Type

Label
Description
Header Ego‑Remote AMS Message Header – Standard “CAV‑ERA‑Vx.y”.
MInstanceID Identifier of the M-Instance (Virtual Space) associated with this Ego‑Remote AMS Message.
UEnvironmentID Identifier of the U-Environment (Real Space) associated with this Ego‑Remote AMS Message.
EgoRemoteAMSMessageID Unique identifier of this Ego‑Remote AMS Message instance.
EgoRemoteAMSMessageTime Time this Ego‑Remote AMS Message was produced.
EgoRemoteAMSMessageSpaceTime Space/Time where/when this Ego‑Remote AMS Message applies.
CAVIdentifier Identifier of the CAV sending this message.
Message One of the five message types exchanged between Ego and Remote AMS.
RequestMessage Message from the Ego CAV requesting information from the Remote CAV.
    – EgoCAVID Identifier of the Ego CAV sending the request.
    – ULocation Specification of the portion of the Remote CAV’s Environment to be provided.
ResponseMessage Message from the Remote CAV providing the requested information.
    – RemoteCAVID Identifier of the Remote CAV providing the response.
    – RemoteFED Subset of the Remote CAV’s Full Environment Descriptors relevant to the requested U‑Location.
SenderInfoMessage Message from the Ego CAV providing its intended Trajectory to the Remote CAV.
    – EgoCAVID Identifier of the Ego CAV.
    – Trajectory Trajectory the Ego CAV intends to adopt.
ReceiverInfoMessage Message from the Remote CAV accepting or rejecting the Ego CAV’s intended Trajectory.
    – EgoCAVID Identifier of the requesting Ego CAV.
    – AcceptReject Whether the Remote AMS accepts or rejects the Ego CAV’s intended Trajectory: “Accept” or “Reject”.
AMSAlertMessage Message alerting the Remote CAV about the Ego CAV’s status.
    – EgoCAVID Identifier of the Ego CAV sending the alert.
    – AMSAlertID Alert type: one of Ambulance, Authority, Health, Evacuation.
    – RoadState Appropriate subset of the Road State.
    – CAVState Appropriate subset of the CAV State.
DataXMData MPAI-PTF Data Exchange Metadata providing provenance, authorisation, legal, security, and confidence information associated with this Ego‑Remote AMS Message in a trusted data exchange context.
DescrMetadata Human-readable descriptive metadata of the Ego‑Remote AMS Message (plain text, max 2048 characters).

5      Conformance Testing

A Data instance conforms with Ego‑Remote AMS Message (CAV‑ERA) if:

  1. The Data validates against the Ego‑Remote AMS Message’s JSON Schema.
  2. All Data in the Ego‑Remote AMS Message’s JSON Schema:
    1. Have the specified type.
    2. Validate against their JSON Schemas.
    3. Conform with their Data Qualifiers.

6      Performance Assessment

Not part of this specification.

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