Patent ID: 8226194

Claim:
An apparatus comprising: a print head configured to, during a printing operation, deposit one or more printing substances onto a print surface of a print medium; navigation sensors configured to provide (i) during a mapping operation, mapping data of a print spot of the print surface, wherein the mapping operation occurs prior to the printing operation, and wherein the mapping data includes three dimensional location information of the print spot of the print surface, and (ii) during the printing operation, positioning data of the apparatus; a position module configured to based upon the mapping data received from the navigation sensors, generate mapping information of the print surface, and based upon the positioning data received from the navigation sensors, generate positioning information indicating three dimensional location information of the apparatus relative to the print medium; and a print module configured to control the print head to cause the print head to deposit or to not deposit the one or more of the printing substances onto the print spot based, at least in part, on comparing the positioning information to the mapping information, wherein the mapping data includes a first tilt value associated with the print spot, and the positioning data includes a second tilt value associated with the apparatus, the second tilt value being related to a position of the print head with respect to the print surface, and wherein the print module is further configured to cause the print head to deposit or to not deposit the one or more of the printing substances onto the print spot based, at least in part, on whether the second tilt value is within a predetermined range of the first tilt value.