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Next: Materials Up: Common sense Ontologies Previous: Time


The Blocks World is a simple example of we can model and describe space.

However common sense notions such a place object x near object y are not accommodated.

Now objects have a spatial extent while events have a temporal extent.

So we might try to extend of common sense theory of time.

However space is 3D and there are many more relationships than those for time so it is not a good idea.

Another approach is view objects and space at various levels of abstraction. E.g. We can view most printed circuit boards as being a 2D object.

Choosing a representation means selecting relevant properties at particular levels of granularity.

For instance we can define relations over spaces such as inside, adjacent etc.

We can also define relations for curves, lines, surfaces, planes and volumes. E.g. along, across, perpendicular etc.