Patent ID: 6175357
Filing Date: 2001-01-16
Classification: G06F

Abstract:
A method of tracking attitude of a device comprising the steps of:fixing a two-dimensional array of photosensors to said device;attaching an optical means to said device to image features of an environment onto said photosensors, said optical means having a lens system for providing a focus for imaging by said array, said lens system having a characteristic of introducing curvilinear distortion of an image to said array;utilizing said two-dimensional array to acquire a first image of features within a field of view of said array, said array having a shape to achieve compensation of said curvilinear distortion, including having arcuate edges to establish said compensation;storing said first image;utilizing said two-dimensional array to acquire a second image of features within said field of view at a time subsequent to acquiring said first image, said first and second images being images of regions that are largely overlapping such that there are features common to both of said first and second images;correlating said first and second images to detect differences in location of said common features within said first and second images; andbased upon said step of correlating, forming an attitudinal signal indicative of any changes in angular orientation of said device during an interval between acquiring said first and second images.