Multiview calibration of an active vision head

In this paper a method to automatically calibrate a pan/tilt head using an imaging vision system is shown. The vision sub-system uses two cameras. Both cameras must be calibrated before. A pattern to perform the automated calibration has been constructed. The camera calibration, using that pattern, consists of two stages: capture the data online and calibrate offline in few seconds. The first task has been subdivided in another two: detection and tracking the pattern. To obtain the value of the parameters that govern the behaviour of the system, the 3D positions of the pattern points are matched in both cameras. The problem becomes a problem of minimising the position error of pattern points given by the active vision head to the real ones given by the external camera. Check and test the calibration of the system is straightforward viewing the residual errors obtained by the minimisation algorithm. Thus, an automated calibration of the active vision head based on a multiview approach has been performed.