To introduce the RSL concept and the Information Model, the example in Figure 1 has been introduced. It shows an example of objects and their relative spatial locations.

The example shows a table with its location (green coordinate system at the foot of the table) relative to the base coordinate system (blue coordinate system below the table) and a defined attach-point at the corner of the table (red coordinate system) on which a chess board and chess pieces are placed. Other objects can be defined in relation to the attach-point at the corner of the table, such as the brown queen or the chessboard.

For an object (e.g. the chess board) positions (e.g. fields) can be defined as attach-points, which span up coordinate systems where other objects (e.g. chess pieces) can be placed i.e. their positions will be described with respect to the attach-point.

The chess pieces on the board can be related to the chess board or to a field on the board, so changing the position of the board would have no impact on the position of chess pieces, which are related directly or indirectly to the chess board. Changing the position of the table would not impact the relative positions of all those objects, which are directly or indirectly related to the table position.

The yellow arrow describes an alternate frame for the position of the white king, related directly to the base reference coordinate system (blue).

Annex C provides detailed example views for the use of the Relative Spatial Location concept described with this example of a chess board on a table.

Figure 1 – Example of a chess table with relative positions of objects