1   Definition

A Motor Command is a directive issued by the Motion Actuation Subsystem to a traction or steering motor of a Connected Autonomous Vehicle (CAV). It defines what the motor shall achieve- typically expressed as target velocity, torque, or position – together with when and how to apply the command.

MPAI‑CAV deployments increasingly rely on motors requiring richer descriptions:
• precise torque envelopes,
• state‑dependent limits,
• health and temperature awareness,
• actuator‑side feedback expectations,
• safety overrides.

2   Functional Requirements

A Motor Command shall:

  1. Identify the Command and Motor: Include unique identifiers for the command lifecycle and the target Motor.
  2. Support Multi‑Mode Actuation: Express control in velocity, torque, acceleration, or position, depending on motor type.
  3. Provide Timing Information: Include the intended moment of application, duration, or scheduling within the control cycle.
  4. Support Safety‑Aware Execution: Incorporate optional limits and safety thresholds (current, temperature, torque caps).
  5. Allow Explicit Control Profiles: Enable multi‑phase envelopes (e.g., ramp‑up, hold, ramp‑down).
  6. Include Optional Predictive Control Parameters: Such as feed‑forward torque correction or expected load compensation.
  7. Support Data Exchange and Traceability: Provide standard AIF V3 metadata for logging and system verification.
  8. Be Forward‑Compatible: Allow future additions without breaking existing deployments (via optional fields).

3   Syntax

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

4   Semantics

Label Description
Header Motor Command Header — standard “CAV‑MRC‑Vx.y”, where x.y is the version.
MotorCommandID ID of the Motor Command instance.
MotorID Identifier of the addressed Motor.
MotorCommand Set of Motor Command parameters.
– MotorCommandTime Time interval during which the command shall be applied.
– ControlMode Specifies which control modality is active: velocity, torque, position, or acceleration.
– TargetVelocity Target velocity expected at the end of the commanded duration (only when ControlMode = velocity).
– TargetTorque Target torque to be produced by the motor (only when ControlMode = torque).
– TargetPosition Target shaft/steering position (only when ControlMode = position).
– TargetAcceleration Target acceleration to be produced (only when ControlMode = acceleration).
– ControlProfile Optional multi‑phase actuation profile (ramp‑up, hold, ramp‑down), each with its duration and optional velocity/torque/acceleration values.
– SafetyLimits Optional safety envelope including maximum allowable current, maximum temperature, and maximum torque.
– HealthAwareness Optional health‑aware parameters such as thermal derating mode, expected load estimate, or motor‑state hint.
DataExchangeMetadata Metadata describing exchange, processing context, and runtime characteristics (AIF V3.0).
Trace Trace information enabling reproducibility and auditability of the Motor Command (AIF V3.0).
DescrMetadata Optional descriptive metadata.