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 measure spatial and angular values of each of CartPosition, SpherPosition, CartVelocity, SpherVelocity, CartAccel, SpherAccel.
  • Measurement of Error is assumed to be the same for the three components of each value set.

3      Syntax

https://schemas.mpai.community/OSD/V1.1/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
– 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
ObjectPositionID N4 Bytes  Identifier of Object Position.
General    
– CoordType bit 0 0: Cartesian, 1: Spherical
– ObjectTypeID bit 1-2 00: Digital Human; 01: Generic; 10 and 11: reserved
– MediaTypeID bit 3-5 000: Audio; 001: Visual; 010: Audio-Visual; 011: Haptic; 100: Smell; 101: RADAR; 110 LiDAR; 111: Ultrasound.
– Cart Precision bit 6 0: single precision; 1: double precision
– SpherPrecision bit 7 0: single precision; 1: double precision
– SpatialAttitudeMask 2 Bytes 3*3 matrix of booleans (by rows)

Position Velocity Acceleration
Cartesian
Spherical
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 N5 Bytes Err/CartPosition*100
– ErrSpherPosition N6 Bytes Err/SpherPosition*100
– ErrCartVelocity N8 Bytes Err/CartVelocity*100
– ErrSpherVelocity N9 Bytes Err/SpherVelocity*100
– ErrCartAccel N11 Bytes Err/CartAccel*100
– ErrSpherAccel N12 Bytes Err/SpherAccel*100
DescrMetadata N13 Bytes Descriptive Metadata

5       Data Types

Object Types, Media Types, and Coordinate Types are required.

6       To Respondents

Respondents are requested to comment on Functional Requirements and Object Type ID, Media Type ID, and Coordinate Type ID.