43 БЪЛГАРСКА АКАДЕМИЯ НА НАУКИТЕ • BULGARIAN ACADEMY OF SCIENCES ПРОБЛЕМИ НА ТЕХНИЧЕСКАТА КИБЕРНЕТИКА И РОБОТИКАТА, 62 PROBLEMS OF ENGINEERING CYBERNETICS AND ROBOTICS, 62 София • 2010 • Sofia Ultrasonic Positioning System for Mobile Robots Nayden Chivarov*, Stefan Shivarov** * Institute of Systems Engineering and Robotics, 1113 Sofia ** Code Assitance Ltd., 1606 Sofia E-mails: nshivarov@code.bg shivarov@code.bg 1. Introduction Positioning systems are widely used today in many fields of applications. A similar system is the Global Positioning System (GPS) [1]. It is a world-wide positioning and navigation system, used for civil, as well as military purposes. It allows comparatively precise determining of the location and route of persons, cars and other vehicles, etc. The precision of the system is good enough for navigation throughout the whole road map of the world and is even better for military purposes. However, this precision is far from adequate for other purposes, where smaller areas with increased accuracy requirements apply, i.e., robot navigation for industrial or service applications. Such scenarios require their own positioning and navigation system in order to achieve adequate precision in a centimeter or even milimeter range. Several types of systems covering these tasks have been developed today, employing similar techniques to the common GPS system, but implemented either with infrared or ultrasonic waves (or combination of both). Due to the specific requirements in such applications and the search for economically adequate solutions, radio waves are mostly used as a tool for synchronization rather than a primary source of distance/coordinate information.