Record Details     « New Search       Brief Record Full Record MARC Record     Bibliographic Data Control Number UPD-00014951850 Date and Time of Latest Transaction 20090717042358.0 General Information 080209s1996 ph a 000 eng Language Code eng Cataloging Source DML Authentication Code DMLUC Local Call Number LG 995 1996 E6 A53 Main Entry - Personal Name Andales, Zaldy A. Title Statement An auto-orienting error-recovering fuzzy navigation system for initially unknown environments : design and simulation / Zaldy A. Andales Publication, Distribution, Etc. 1996 Physical Description 185 leaves : ill General Note Computer print-out Dissertation Note Thesis (M.S.)--University of the Philippines, Diliman Summary, Etc. The main objective of the study was to device and integrate fuzzy logic-based auto-orienting and error-recovering schemes for a fuzzy navigation system of an Automated Guided Vehicle (AGV) placed in an initially unknown, stationary and flat environment. As a testbed for simulation, AGV and environment simulators were created. As a basis for the fuzzy navigation rules, the AGV assumed four inputs (three ultrasonic range sensor values and the target direction) and two outputs (AGV direction and speed). A single photo sensor was assumed for detecting targets. A fuzzy navigation system was implemented employing 81 IF-THEN rules. For the auto-orienting scheme, it was assumed that multiple targets were placed near perimeter walls, and a fuzzy wall-following system was successfully implemented to automatically detect all targets and map out their locations. For error-recovery, a fuzzy spiral search system was successfully devised for recovery from shift and dislocation errors. This strategy required the AGV to scan its vicinity by following a spiral path until the target was found. A fuzzy wall-following search system, on the other hand, successfully provided recovery from timeouts and trap errors. Thus all errors were effectively recovered from with minimal assumed sensors installed. These schemes were integrated with the normal fuzzy navigation system to form the Integrated Fuzzy Navigation System (IFNS). Switching between schemes was managed by an over-all task planner. To evaluate the IFNS, an A* Heuristic Search-based Configuration Space System was implemented (ACSS). The ACSS, being an optimal path finding technique served as the standard. Results showed that the path efficiency was 84.9899% with respect to the optimal. However, by employing sub-goals or intermediated targets as guides, the path length efficiency improved to 94.7859%. Sub-goals also proved to be effective in eliminating trap and timeout situations Subject Added Entry - Topical Term Automated guided vehicles systems   Fuzzy logic   Fuzzy systems Collection Category FI Location UP DENG-II LG 995 1996 E6 A53 Room-Use Only E2-33t Collection Category UP Location UP DARCHIVES LG 995 1996 E6 A53 Room-Use Only UARD-8605t   UP DENG-II LG 995 1996 E6 A53 Room-Use Only E2-33t Textual Physical Form Designator Thesis           Physical Location University of the Philippines Diliman Main Library: University Archives LG 995 1996 E6 / A53 Diliman: College of Engineering Library II LG 995 / 1996 E6 A53 Diliman: College of Engineering Library II LG 995 1996 E6 / A53           Digital Copy Not Available          Add to Book Cart  |   Download MARC