Development of automated milking equipment: Detection of teat location by image processing

The purpose of this study is to develop an automatic teat-cup attachment in milking robot. By processing a two-valued image from a small CCD camera, a method of detecting the teat position of cow was investigated. After proofreading equations between the distance to the teat and the real coordinate were obtained by experiment, simulation using an udder model, a teat model and a marker was carried out, and the accuracy of detecting the teat position was examined. The results of the experiment showed that the maximum and the average errors of Z coordinate using a marker were +6.7mm and 1.5mm, and those of the XY plane coordinate were 2.1mm and 1.2mm respectively, in the space coordinates of a robot arm working range, i.e. X coordinate -40 to +20mm, Y coordinate 370-670mm and Z coordinate to 260-460mm. The error of the detected coordinate using a teat model increased from 0mm (minimum value) in the center area of the image frame to 3.4mm (maximum value) in the fringe area