1     Definition 2     Functional Requirements 3     Syntax
4     Semantics 5    Conformance Testing 6     Performance Assessment

1      Definition

A Data Type representing an Object’s position, velocity, and acceleration.

2      Functional Requirements

  • The Position of an Object is that of a representative point in the Object.
  • Cartesian and Polar Coordinate Systems are supported.
  • An Object may have one of the following attributes: Speech, Audio; Visual; 3D Model, Audio-Visual; Haptic; Smell; RADAR; LiDAR; Ultrasound.
  • Accuracy is the estimated absolute difference between the measured spatial values of each of CartPosition, SpherPosition, CartVelocity, SpherVelocity, CartAccel, SpherAccel and their true value.

3      Syntax

https://schemas.mpai.community/OSD/V1.2/data/Position.json

4      Semantics

Table 1 provides the semantics of Position. It should be noted that each of Position, Velocity, and Acceleration can be expressed either in Cartesian (X,Y,Z) or Spherical (r,φ,θ) Coordinates.

Table 1 – Semantics of the Spatial Attitude

Label Size Description
Header N1 Bytes Position Header
– Standard-Position 9 Bytes The characters “OSD-OPS-V”
– Version N2 Bytes Major version – 1 or 2 characters
– Dot-separator 1 Byte The character “.”
– Subversion N3 Bytes Minor version – 1 or 2 characters
MInstanceID N4 Bytes ID of Virtual Space Position refers to.
ObjectPositionID N5 Bytes  Identifier of Object Position.
General N6 Bytes Set of general data
– CoordinateType N7 Bytes One of Cartesian, Spherical, Geodesic, Toroidal.
– ObjectType N8 Bytes One of Digital Human, Generic.
– MediaType N9 Bytes One of Speech, Audio, Visual, 3D Model, Audio-Visual, Haptic, Smell, RADAR, LiDAR, Ultrasound.
Position
– CartPosition (X,Y,Z) N10 Bytes Array (in metres)
– CartPositionAccuracy (X,Y,Z) N11 Bytes Array of CartPositionAccuracy
– SpherPosition (r,φ,θ) N12 Bytes Array (in metres and degrees)
– SpherPositionAccuracy (r,φ,θ) N13 Bytes Array of SpherPositionAccuracys
Velocity of Position
– CartVelocity (X,Y,Z) N14 Bytes Array (in metres)
– CartVelocityAccuracy (X,Y,Z) N15 Bytes Array of – CartVelocityAccuracys (X,Y,Z)
– SpherVelocity (r,φ,θ) N16 Bytes Array (in metres and degrees)
– SpherVelocityAccuracy (r,φ,θ) N17 Bytes Array of SpherVelocityAccuracys
Acceleration of Position
– CartAccel (X,Y,Z) N18 Bytes Array (in metres)
– CartAccelAccuracy (X,Y,Z) N19 Bytes Array of CartAccelAccuracys
– SpherAccel (r,φ,θ) N20 Bytes Array (in metres and degrees)
– SpherAccel (r,φ,θ) N21 Bytes Array (in metres and degrees)
DescrMetadata N22 Bytes Descriptive Metadata

5     Conformance Testing

A Data instance Conforms with MPAI-OSD V1.2 Position (OSD-OPS) if:

  1. The Data validates against the Position ’s JSON Schema.
  2. All Data in the  Position ’s JSON Schema have the specifies type.

6     Performance Assessment