| || || Robots -- Control systems|
| || || Development of an automatic guided vehicle with an obstacle avoidance system |
Author: Kumar, Shivendra.
Institution: University of the South Pacific.
Subject: Robots -- Control systems , Vehicles, Remotely piloted , Intelligent control systems
Call No.: pac TJ 211 .35 .K85 2003
Copyright:Under 10% of this thesis may be copied without the authors written permission
Abstract: Optical guidepath following automatic guided vehicles (AGV) have its applications limited due to its inability to avoid obstacles that block its path forward. This research therefore develops an AGV that follows optical guidepath for navigation and is able to able to maneuver around obstacles. An algorithm that detects obstacles and avoids them is presented first. This algorithm, called the guidepath following certainty grid (GFCG) method uses data from infra red (IR) ranging sensors located in front of the AGV to detect and avoid obstacles. After maneuvering around the obstacle using the contour of the obstacle, the AGV rejoins the guidepath and resumes its movement towards its destination. Details on the framework of the AGV, its control circuitry and organization of intelligence are then discussed. The aluminum framework housing the circuitry and load/ unload unit uses DC motors for movement. The AGV receives information about its environment from IR sensors in the front and the side, line tracing sensors and a hall effect compass. Coordination and processing of intelligence is performed by a PIC16F877 microcontroller. Experimental results on line tracing, response distances and obstacle avoidance are presented thereafter. Results in line tracing and response distances exhibit orientation errors of the AGV. The response distance of the AGV upon detecting an obstacle or a station is also presented along with path maps taken by the AGV to avoid obstacles placed at different positions. The conclusion summarizes the features and capabilities of the AGV and discusses the implications of this research to the region. Areas of further research are also discussed.