Patent Document ID: 5499306
Application ID: 08206828
Patent Status: 1

Claim One:
1. A position and attitude recognition method for determining the position and attitude of an image pickup means with respect to an object having three-dimensional shape, the method comprising: an image pickup step using the image pickup means for taking two-dimensional image information of the object; an image processing step for extracting actual image feature representing the shape of an object, on the basis of said two-dimensional image information of said object taken by said image pickup means; a search region setting step for setting a search region with a plurality of discrete space points having a required accuracy in discrete value and allocated in the vicinity of said image pickup means whose position and attitude are estimated based on external information; perspective transformation equation calculating step for obtaining a perspective transformation equation for calculating two-dimensional estimated image feature of said object to be obtained when a view of said object is taken by said image pickup means located at each of said discrete space points of said search region, derived from the three-dimensional shape of said object; an error calculating step for calculating an error between said actual image feature extracted by said image processing step and said estimated image feature calculated by said perspective transformation calculating step for each of said discrete space points; and a searching step for searching each of said discrete space points to find a space point which has a minimum error between said actual image feature and said estimated image feature, thereby determining the position and attitude of said image pickup means with respect to said object.