Abslmcr-lhis paper proposes a method for Qmullanmus lodiratiun and mapping tSLAW h an indoor cnvimnment usin8 stereo \ision. Specially designed actilicial landmarks distributed in thc environment arv uhsened and extracted lmm a m i c r a image. The disparity map ob(;lined lrom the stem, &ion syswm is used to obtain the ranges l o these landmark% ' The main contribution of thc paper is the formulation of the mnthcmatieal lramcwrk lor SLAII lor a rubot mo5ing on a plwar surface ammg landmarks distributed in three dimensional space. 'The paper also presents the results of experiments conducted using a Pioneer robot and a Triclops stem, vbiun rpllem. It is demonstrated that accurate mho1 and luarure Ii~atiuns can be oblained using the proposed technique. I. ~N I K O U U C I ' I O \ 1The general SLAM problem has been the subject of sub\tanual rescuch in the past Cew years I I I. SLAM using \'i,inn is hecoming mure and more iniponanr due IO the recent developments in image proce,,ing. Therefurz. vision hased rohot nwipation has attracted cigniticant attenuon 121. 1 1 1 m d 141.Current dereo vi5ion systms c3n provide depth informauun from a scene at frame-raw. ' The di,pant) map provided by a stereo system can be used to detmnine range. bearing and elevation to point feanire\ in the environnient. AIthough extracting feature points from a given 5cene image m a complicated process in 11s own nght. utilizing this knowledge is ablc tu infer the fz3tu1e locations with respect to a three dmiensional world cwrdinatc \y\tenl and in turn using such feature pciinls to localize the robot itself in this ccrirtlinare \ystelii is nothing less of a challenge [SI.I n case of vision bascd SLAM. the challenge i, to provide a con*i\tcnt map building method that dlows the unknown coordinates of features in the environmenr together with the coordinatsi (if the robot. ln ths paper we provide a twhniquec to achieve this and pmvidc some erperiniental resuls tn verify the proposed algorithms.We improw on the e4matiun process based on the extended Kalman filter (EKFj hy sitending it to accomm&tc a three-diniznsional world coordnate model. Thls paper extends the "the process model" module and "the ohwnation tiiodel" from ?I) to lD. 'The other contribution made in thi, paper to the rhree-dimensional SLA.M problem IS the usc of dixplmty maps as a mean, ofextracting spatial information of identined fcatur: positions. 0-7803-8483-Sl041$20.00 WO04 IEEE FORMULATIONAs the robot with a known kinematic model starts at an unknown location and moves through an environment containing a number of features or landmarks, we must provide the procedure how we know and estimate of the robot position and landmark locations in Cartesian coordinates. A. Discrere Robot and Landmark ModelsWe elaborate a discrete time index in this section replacing the continuous time index. The absolute locations of the landmarks are not available. Without prejudice, a linear (synchronous) discrete time model of the evolution of the robot state and the observations of landmarks is ado...

This paper proposes a optimal control method for simultaneous localisation and mapping (SLAM) in an indoor environment using stereo vision. Specially designed artificial landmarks distributed in the environment are observed and extracted from a camera image. The disparity map obtained from the stereo vision system is used to obtain the ranges to these landmarks. The main contribution of the paper is the formulation of the mathematical framework for SLAM for a robot moving on a planar surface among landmarks distributed in three dimensional space. The paper also presents the results of experiments for optimal control conducted using a Pioneer robot and a Triclops stereo vision system. It is demonstrated that accurate robot and feature locations can be obtained using the proposed technique.

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The near-field measurement of fully turbulent jets discharged from a straight circular pipe indicates the presence of quasiperiodic velocity perturbations. The Strouhal number based on the predominant frequency falls in the range of the preferred mode for the jet with a potential core and has an asymptotic value of 0.38 in the high Reynolds number regime. Regular perturbations are not observed in the mixing region immediately downstream from the pipe exit.

This paper proposes a method for simultaneous localisation and mapping (SLAM) in an indoor environment using stereo vision. Specially designed artificial landmarks distributed in the environment are observed and extracted from a camera image. The disparity map obtained from the stereo vision system is used to obtain the ranges to these landmarks. The main contribution of the paper is the formulation of the mathematical framework for SLAM for a robot moving on a planar surface among landmarks distributed in three dimensional space. The paper also presents the results of experiments conducted using a Pioneer robot and a Triclops stereo vision system. It is demonstrated that accurate robot and feature locations can be obtained using the proposed technique.