<-Scope Go to ToC References->
Capitalised Terms used in CAV-ARC and CAV-TEC have the meaning defined in Table 1. All MPAI Terms defined here. Non-capitalised terms letter have the meaning commonly defined for the context in which they are used or represent an entity in the real world. For instance,
- Table 1 defines Object, Scene, and User but does not define object, scene, and human.
- Object indicates an Item but “object” is used to indicates an entity in the Universe commonly classified as object.
A dash “-” preceding a Term in Table 1 means the following:
- If the font is normal, the Term in the table without a dash and preceding the one with a dash should be placed before that Term. The notation is used to concentrate in one place all the Terms that are composed of, e.g., the word Brake followed by one of the words Command and Response.
- If the font is italic, the Term in the table without a dash and preceding the one with a dash should be placed after that Term. The notation is used to concentrate in one place all the Terms that are composed of, e.g., the word Attitude preceded by one of the words Social and Spatial.
Table 1 – CAV-specific Terms and Definitions
| Term | Definition |
| Acceleration | The 2nd order time derivative of a Position or Orientation. |
| – Coordinate | The acceleration measured in a coordinate system. |
| – Proper | The physical acceleration, i.e., measured by an accelerometer experienced by an object. |
| Accuracy | An estimate of how well the measurement of a physical entity corresponds to the actual value of that entity. |
| Alert | A Data Type representing environment-related elements that should be treated with priority by the Obstacle Avoider AIM. |
| AMS-MAS Message | A Data Type representing the command issued by the Autonomous Motion Subsystem instructing the Motion Actuation Subsystem to change the Ego CAV’s Spatial Attitude SAA at time tA to Spatial Attitude SAB at time tB and the response of the MAS to the AMS-MAS Message. |
| AMS-HCI Message | A Data Type representing high-level instructions issued by HCI to AMS to request it to reach a destination and the response of the AMS. |
| Brake | A mechanical system connected to the Autonomous Motion Subsystem. |
| – Command | A Data Type representing the command that the Motion Actuation Subsystem issues to the Brakes after interpreting an AMS-MAS Message. |
| – Response | A Data Type representing the Brakes’ response to the AMS Command Interpreter in response to a Brake Command. |
| CAV | See Connected Autonomous Vehicle. |
| – Aware | An attribute of equipment possessing some of the sensing and communication capabilities of a CAV without being a CAV, e.g., Roadside Units and Traffic Lights. |
| – Centre | The point in the Ego CAV selected to have coordinates (0,0,0). |
| – Ego | The Object in the Environment that the CAV recognises as itself. |
| – Identifier | A Data Type uniquely identifying a CAV and carrying information, such as: 1. Country code where the CAV has been registered. 2. Registration number in that country. 3. CAV manufacturer identifier. 4. CAV model identifier. |
| Connected Autonomous Vehicle | (CAV) The information technology-related components of a vehicle enabling it to autonomously reach a Pose by: 1. Understanding human utterances in the Subsystem (HCI). 2. Planning a Route (AMS). 3. Sensing and building a Representations of the external Environment (ESS). 4. Exchanging such Representations and other Data with other CAVs and CAV-aware entities (AMS). 5. Making decisions about how to execute the Route (AMS). 6. Acting on the MAS (AMS). |
| – State | A Description of the state of the CAV generated by the CAV’s AMS using information available inside the CAV as assessed by the CAV and received from an external source, e.g., another CAV or Roadside Unit. |
| Data | Information in digital form |
| – Accelerometer | A Data Type representing the acceleration forces acting on a CAV. |
| – Environment | A Data Type representing the Environment such as produced by an Environment Sensing Technology or derived from the Basic or Full Environment Representation. |
| – LiDAR | A Data Type representing Data captured by a LiDAR sensor. |
| – Odometer | A Data Type representing the distance from the start up to the current Pose measured by the number of wheel rotations times the tire circumference (π x tire diameter). |
| – Offline Map | A Data Type representing the Data provided by an Offline Map in response to a given set of coordinate values. |
| – RADAR | A Data Type representing the Visual Data captured by a RADAR sensor. |
| – Speedometer | A Data Type representing the speed of a CAV as measured by the sensor. |
| – Ultrasound | A Data Type representing the Data provided by an ultrasonic sensor. |
| – Weather | Weather Data is a set of data that includes Temperature, Humidity, Air Pressure, Ice conditions, Wind conditions and Condensed water in various states. |
| Decision Horizon | The time interval within which a decision is planned to be implemented. |
| Environment | The Digital Representation of the portion of the environment of current interest to a CAV. |
| – Sensing Technology | (EST) One of the technologies used to sense the environment by the Environment Sensing Subsystem, e.g., RADAR, LiDAR, Visual, Ultrasound, Audio, and including the Offline Map. |
| Environment Scene Descriptors | A Data Type representing the combination of EST-specific 2D, 2.5D, or 3D Scene Descriptors used by an EST Scene Description in an EST-specific time window. |
| – Basic | (BED) A Data Type representing Environment using information provided by a variety of sensors and including: – The Ego CAV’s Spatial Attitude. – The Scene Description produced from the available Environment Sensing Technologies. – Weather Data. |
| – Full | (FED) A Data Type representing the Environment that extends the Basic Environment Representations of the Ego CAV with elements of those of other CAVs in range or Roadside Units. |
| Global Navigation Satellite System (GNSS) | One of the systems providing global navigation information such as GPS, Galileo, Glonass, BeiDou, Quasi Zenith Satellite System (QZSS) and Indian Regional Navigation Satellite System (IRNSS). |
| Goal | The Spatial Attitude planned to be reached at the end of a Decision Horizon. |
| Inertial Measurement Unit | An inertial positioning device, e.g., odometer, accelerometer, speedometer, gyroscope etc. |
| Latitude | A Data Type representing the angular distance of a point on the surfave of the Earth lace north of the equator measured in degrees. |
| LiDAR | A Data Type representing analogue signals generated by information captured by an active time-of-flight sensor operating in the µm range – ultraviolet, visible, or near infrared light (900 to 1550 nm). |
| Longitude | A Data Type representing the angular distance of a place west of the Greenwich meridian measured in degrees [4]. |
| MAS Subsystem | The CAV Subsystem interpreting AMS-MAS Messages; issuing commands and receiving responses from Brakes, Wheel, and Motors; and responding with AMS-MAS Messages. |
| Motor | A mechanical system connected to the Autonomous Motion Subsystem. |
| – Command | A Data Type representing the command issued to a Motor by the Motion Actuation Subsystem after interpreting an AMS-MAS Message. |
| – Response | A Data Type representing the Motor’s response to AMS Command Interpreter in response to a Motor Command. |
| Offline Map | A previously created digital map of an Environment and associated metadata. |
| Path | A Data Type representing a sequence of Poses. |
| Pose | A Data Type representing Position and Orientation of the CAV as obtained by processing the data from the CAV sensors. |
| RADAR | A Data Type representing analogue signals generated by information captured by an active time-of-flight sensor operating in the operating in the 24-81 GHz range. |
| Remote | An attribute of a CAV Subsystem opposed to “Ego”. |
| – AMS | AMS of a CAV or CAV-Aware entity in range. |
| – HCI | HCI of a CAV or CAV-aware entity in range. |
| Road | |
| – Geometry | A Data Type representing the positioning of the physical elements of the roadway, e.g., traffic poles, road Signs, traffic tights, etc. |
| – State | A Data Type representing the state of the road the CAV is traversing such as detours and road conditions. |
| – Topology | The geometric properties and spatial relationships of objects in a traffic environment. |
| Roadside Unit | A wireless communicating device located on the roadside providing information to CAVs in range. |
| Route | A Data Type representing a sequence of Waypoints. |
| Scene Descriptors | |
| – LiDAR | A Data Type describing the LiDAR Data and produced by the LiDAR Scene Description AIM using previous Basic Environment Representations. |
| – Offline Map | A Data Type including the objects of a Scene described by an Offline Map. |
| – RADAR | A Data Type representing the Visual Data captured by RADAR and produced by the RADAR Scene Description AIM using previous Basic Environment Representations. |
| – Ultrasound | A Data Type representing the Visual Data captured by Ultrasound and produced by the Ultrasound Scene Description AIM using previous Basic Environment Representations. |
| Shape | A Data Type representing the volume occupied by a CAV. |
| Subsystem | One of HCI, ESS, AMS, and MAS. |
| Traffic | |
| – Rules | A Data Type representing the traffic rules applying to an Environment as extracted from the local Traffic Signals based on the local traffic rules. |
| – Signals | A Data Type representing the traffic signals on a road and around it, their Spatial Attributes, and the semantics of the traffic signals. |
| Ultrasound | A Data Type representing analogue signals generated by information captured by an ultrasonic sensor, an active time-of-flight sensor typically operating in the 40 kHz to 250 kHz range. |
| Waypoint | The coordinates of a point on an Offline Map. |
| Wheel | A mechanical system connected to the Autonomous Motion Subsystem. |
| – Command | A Data Type representing the command issued to the Steering Wheel by the Motion Actuation Subsystem after interpreting an AMS-MAS Message. |
| – Response | A Data Type representing the Wheel’s response to the AMS Command Interpreter in response to a Direction Command. |
Table 2 defines the Terms used in this Technical Specification that are not already included in Table 1.
Note: To concentrate in one place all the Terms that are composed of a common name followed by other words (e.g., the word Data followed by one of the words Format, Type, or Semantics), the definition given to a Terms preceded by a dash “-” applies to a Term composed by that Term without the dash preceded by the Term that precedes it in the column without a dash.
