The article describes a study of problem of estimating the position coordinates of Autonomous Biomimetic Underwater Vehicle (ABUV) using two methods: dead reckoning (DR) and extended Kalman filter (EKF). In the first part of the paper, navigation system of ABUV is described and scientific problem with underwater positioning is formulated. The main part describes a way of estimating the position coordinates using DR and EKF and a numerical experiment involving motion of ABUV along the predetermined test distance. The final part of the paper contains a comparative statistical analysis of the results, carried out for assessing the accuracy of estimation of the position coordinates using DR and EKF methods. It presents the generalized conclusions from the research and the problems relating to the proper placement of the components of the system measuring distances.
 Felski A. Nowak A. Woźniak T. Accuracy and availability of EGNOS - results of observations ‘Artificial Satellites’ 2011 Vol. 46 No. 3.
 IMU VN-200 user manual [online] http://www.vectornav.com [access 20.03.2016].
 Mazlan A. N. A. McGookin E. Modelling and Control of a Biomimetic Autonomous Underwater Vehicle. In Proc. International Conference on Control Automation Robotics & Visions Guangzhou 2012 China pp. 88-93.
 Moreno D. An object oriented Matlab framework for underwater SLAM using side scan sonar ‘Actas de las XXXV Jornadas de Automática’ 2014 Valencia Spain pp. 6-14.
 Naus K. Evaluation of accuracy the position of the vessel designated stereoscopic cameras system ‘Reports on Geodesy’ 2010 No. 1 (88) pp. 79-87.
 Naus K. Accuracy in fixing ship’s positions by CCD camera survey of horizontal angles ‘Geomatics and Environmental Engineering’ 2011 Vol. 5/4 pp. 47-61.
 Naus K. Wąż M. Accuracy in fixing ship’s positions by camera survey of bearings ‘Geodesy and Cartography’ 2011 Vol. 60 No. 1 pp. 61-73.
 Naus K. Narloch A. Distribution of the accuracy of position coordinates fixed using coastal navigation methods against two and three navigational markers ‘Logistyka’ 2014 No. 3 pp. 4606-4614.
 Naus K. Electronic navigational chart as an equivalent to image produced by hypercatadioptric camera system ‘Polish Maritime Research’ 2015 Vol. 22 No. 1 (85) pp. 3-9.
 Naus K. Wąż M. Precision in determining ship position using the omnidirectional map to visual shoreline image comparative method ‘Journal of Navigation’ 2016 Vol. 69 Issue 02 pp. 391-413.
 Specification of Hydromodem Micron Data Modem [online] http://www.tritech.co.uk/product/micron-data-modem [access 20.03.2016].
 Szymak P. et al. Report on stage no 2 from development project no. DOBR-BIO4/ 033/13015/2013 entitled ‘Autonomous underwater vehicle with silent undulating propulsion for underwater ISR’ Polish Naval Academy Gdynia 2015.
 Tian S. He B. Chen S. Liu G. Application of forward-looking scanning sonar on Simultaneous Localization and Mapping for an Autonomous Underwater Vehicle In Proc. ICCEE International Conference on Computer and Electrical Engineering Singapore 2012 Vol. 53 No. 2.02 pp. 28-35.
 Wang S. Chen L. Huosheng Hu H. Gu D. Single Beacon based localization of AUVs using moving horizon In Proc. IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) Tokyo 2013 pp. 885-900.