An apparatus and method for optically inferring an absolute pose of a manipulated object in a real three-dimensional environment from on-board the object with the aid of an on-board optical measuring arrangement. At least one invariant feature located in the environment is used by the arrangement for...http://www.google.co.uk/patents/US7826641?utm_source=gb-gplus-sharePatent US7826641 - Apparatus and method for determining an absolute pose of a manipulated object in a real three-dimensional environment with invariant features
