Sharing landmark information using mixture of Gaussian terrain spatiograms

In this paper we evaluate the use of a novel spatial histogram, the terrain spatiogram, as a common representation for exchanging landmark information between robots working as a team to map an area. Individual robots use range sensors to provide the spatial dimension of the spatiogram and video for the image dimension. We have previously shown that terrain spatiograms can be shared between robots in a heterogeneous team to recognize landmarks and to fuse observations from multiple sensors or multiple platforms. A terrain spatiogram using a mixture of Gaussians (MOG) model is introduced and a corresponding normalized spatiogram similarity measure defined. Two methods to generate a MOG terrain spatiogram are presented and compared experimentally using indoor and outdoor landmark information transferred between two different models of robot equipped with differently configured stereocameras.