1        Functions 2        Reference Model 3        Input/Output Data

1       Functions of Connected Autonomous Vehicle

A Connected Autonomous Vehicle is defined as a physical system that:

  1. Converses with humans by understanding their utterances, e.g., a request to be taken to a destination.
  2. Senses the environment where it is located or traverses like the one depicted in Figure 1.
  3. Plans a Route enabling the CAV to reach the requested destination.
  4. Autonomously reaches the destination by:
    • Moving in the physical environment.
    • Building Digital Representations of the Environment.
    • Exchanging elements of such Representations with other CAVs and CAV-aware entities.
    • Making decisions about how to execute the Route.
    • Actuating the CAV motion to implement the decisions.

Figure 1 – An environment of CAV operation

2       Reference Architecture of Connected Autonomous Vehicle

The MPAI-CAV Reference Model is composed of four Subsystems:

  1. Human-CAV Interaction (HCI).
  2. Environment Sensing Subsystem (ESS),
  3. Autonomous Motion Subsystem (AMS).
  4. Motion Actuation Subsystem (MAS).

The Subsystems are represented in Figure 2 where the arrows refer to the exchange of information between Subsystems and between a Subsystem and other CAVs or CAV-aware systems. The sensing of the Environment and the Motion Actuation are represented by icons.

Figure 2 – The MPAI-CAV subsystems

The operation of a CAV unfolds according to the following workflow:

Entity Action
Human Requests the CAV, via HCI, to take the human to a destination.
HCI  1. Authenticates humans.
2. Interprets the request of humans.
3. Issues commands to the AMS.
AMS 1. Requests ESS to provide the current Pose.
ESS 1. Computes and sends the Basic Environment Representation (BER) to AMS.
AMS 1. Computes and sends Route(s) to HCI.
HCI 1. Sends travel options to Human.
Human 1. May integrate/correct their instructions.
2. Issues commands to HCI.
HCI 1. Communicates Route selection to AMS.
AMS 1.     Sends the BER to the AMSs of other CAVs.
2.     Computes the Full Environment Representation (FER).
3.     Decides best motion to reach the destination.
4.     Issues appropriate commands to MAS.
MAS 1.     Executes the Command.
2.     Sends response to AMS.
Human 1.     Interacts and holds conversation with other humans on board and the HCI.
2.     Issues commands to HCI.
3.     Requests HCI to render the FER.
4.     Navigates the FER.
5.     Interacts with humans in other CAVs.
HCI Communicates with HCIs of other CAVs on matters related to human passengers.

1.3       I/O Data of Connected Autonomous Vehicle

Table 2 gives the input/output data of the Connected Autonomous Vehicle.

Table 2 – I/O data of Human-CAV Interaction

Input data From Description
Audio Object Environment Captured Environment by Audio
RADAR Object Environment Captured Environment by RADAR
LiDAR Object Environment Captured Environment by LiDAR
Ultrasound Object Environment Captured Environment by Ultrasound
Text Object Cabin Passengers Text complementing/replacing User input
Visual Object Environment Captured Environment by cameras
Ego-Remote AMS Message Ego AMS Message to Remote AMS
Ego-Remote HCI Message Ego HCI Message to Remote HCI
GNSS Object ~1 & 1.5 GHz Radio Data from various Global Navigation Satellite System (GNSS) sources
Weather Data Environment Temperature, Air pressure, Humidity, etc.
Motor Response Wheel Motor Forces wheels rotation, gives feedback.
Wheel Response Steering Wheel Moves wheels by an angle, gives feedback.
Brake Response Brakes Acts on brakes, gives feedback.
Output data To Description
Ego-Remote AMS Message Remote AMS Message from Ego AMS
Ego-Remote HCI Message Remote HCI Message from Ego HCI
Audio Object Cabin Passengers HCI Response, Rendered Full Environment Descriptors
Text Object Cabin Passengers HCI’s avatar Text.
Visual Object Cabin Passengers Captured Environment by cameras
Motor Command Wheel Motors Activates/suspends wheels rotation, gives feedback.
Wheel Command Steering Wheel Moves wheels by an angle, gives feedback.
Brake Command Brakes Acts on brakes, gives feedback.