Fuzzy Sensor Fusion and Curve Approximation for indoor Map Building

Abstract

This study uses a wheeled mobile robot to explore unknown indoor environment and build up a map of the unknown environment. The robot utilizes ultrasonic and infrared sensors with indoor positioning system to detect obstacles and identify unknown environment. Fuzzy system and sensor fusionare applied to control design. The proposed scheme can control the wheeled mobile robot move along walls and avoid obstacles. Angle and distance of the wheeled mobile robot are used to obtain the path trajectory. With sensed data of obstructions and walls, a map of unknown environment can be generated by curve fitting methods. The map building scheme is tested in different terrains and the experiments confirm that the proposed scheme works properly.

Exploring an Unknown Environment Using Ultrasonic and Infrared Sensors

“…In Ref. 4, the indoor positioning system (StarGazer) is not integrated in the control scheme, and the maximum average errors in the X-and Y-coordinates are 6.5 and 6.2 cm, respectively. In Ref.…”

“…3. (4) Coordinate definitions are given as follows: X-and Y-axes are the global coordinate system; X2 and Y2 are axes of the WMR's local coordinate system; x t and y t are the coordinates of the destination with respect to X and Y axes; x k and y k are the coordinates of the WMR center with respect to X and Y axes; X t ' and Y t ' are the coordinates of the destination with respect to X2 and Y2 axes; θ is the included angle between the X-axis and the center of the WMR; θ e is the included angle between the Y2 axis and the object; φ is the included angle between the X2 axis and the object; and de is the distance between the center of the WMR and the object. The velocity component of the WMR can be approximated with the following difference equation…”

“…In this study, different approaches were applied to map building, all of which have been successfully applied to map building in previous work. (4) Here we provide more comprehensive descriptions of these curve fitting methods and add the StarGazer to the control scheme to provide more accurate position information on the WMR for map building.…”

“…The advantages of the WMR are high-speed mobility, ease of control, and large energy storage capacity. (1)(2)(3)(4)(5)(6)(7)(8) The focus of WMR study is on how to make it work efficiently in various applications. The motivation for this research is to develop an intelligent control system for a WMR exploring an unknown environment.…”

A Review of Sensing Technologies for Indoor Autonomous Mobile Robots

“…The latter was designed to track the target robot. Juang J. G. et al [ 40 ] designed wheeled mobile robots with integrated ultrasonic and infrared sensors that can move along walls and avoid obstacles. Ultrasonic and infrared sensors were used to detect obstacles and identify unknown environments.…”