Patent ID: 7583835
Filing Date: 2009-09-01
Classification: B25J,G05B

Abstract:
1. A process for gripping an object ( 4 ) by means of a robot arm ( 1 ) equipped with a camera ( 2 ), the arm making displacements towards the object, comprising the steps of: using the camera to take a chain of images ( a computer performing the following: wherein the selected points are at boundaries of elements of the images with the first image and the second image compared by computing respective distances Δjk between each points Aj selected in the fist image and each point Bk selected in the second image, polling said distances Δjk for selecting one of said polled distances represented by a majority distance Δm appearing the greatest number of times assuming the selected points in the first image and in the second image separated by the majority distance to belong to the object, computing the position of the object by means of the majority distance, the displacement of the arm between the first image and the second image and known parameters of the camera and wherein the position of the object with respect to the camera is determined as a distance Z from the camera to the object and said distance Z is equal to F(D/ΔpRp)−1), where F is a focal length of a camera lens, ΔpTp is the majority distance and D is a displacement of the arm between the instants at which the first image and the second image were taken.