A Mobile Data Acquisition Platform for Photometric Stereo

The Photometric Stereo Method [14] (PSM) is a wellknown technique in the Computer Vision field that recovers3D shape from a set of images of a still scene, usinga single fixed-pose camera. Every image in the set is takenwhile a change in the direction of the light source occurs.Commonly, the acquisition of PMS imagery implies usingrigid platforms with a static configuration of light sources[5, 13]. In this paper, we explore the use of a mobile platformas an alternative way to obtain PSM imagery. Usinga 5 DOF robotic arm, a light source (placed over the endeffector of the robot) is moved around an object so as to observeconstraints concerning the elevation and azimuth angleof the illumination vector. These constraints are basedon work by Drbohlav and Chantler [3], where a theoreticalstudy about an optimal lightning configuration is introduced.Experiments with objects showing varying reflectanceproperties demonstrate the feasibility of the mobile platformfor the purposes of gathering PSM imagery.