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.
  • The following media used types are supported: Audio; Visual; Audio-Visual; Haptic; Smell; RADAR; LiDAR; Ultrasound.
  • Error is the estimated absolute value of the measured spatial and angular values of each of CartPosition, SpherPosition, CartVelocity, SpherVelocity, CartAccel, SpherAccel.

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

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, Audio-Visual, Haptic, Smell, RADAR, LiDAR, Ultrasound.
– Precision N10 Bytes one of single precision, double precision
Position
– CartPosition (X,Y,Z) 12/24 Bytes Array (in metres)
– SpherPosition (r,φ,θ) 12/24 Bytes Array (in metres and degrees)
Velocity of Position
– CartVelocity (X,Y,Z) 12/24 Bytes Array (in metres)
– SpherVelocity (r,φ,θ) 12/24 Bytes Array (in metres and degrees)
Acceleration of Position
– CartAccel (X,Y,Z) 12/24 Bytes Array (in metres)
– SpherAccel (r,φ,θ) 12/24 Bytes Array (in metres and degrees)
Errors
– ErrCartPosition N11 Bytes Error of CartPosition
– ErrSpherPosition N12 Bytes Error of SpherPosition
– ErrCartVelocity N13 Bytes Error of CartVelocity
– ErrSpherVelocity N14 Bytes Error of SpherVelocity
– ErrCartAccel N15 Bytes Error of CartAccel
– ErrSpherAccel N16 Bytes Error of SpherAccel
DescrMetadata N17 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