An Improved Ultrasonic-Based Localization Using Reflection Method

In this paper, an ultrasonic-based localization using ultrasonic reflection method is proposed. Experiment environment includes a mobile robot and four poles forming a square around the measuring site. Ultrasonic sensors built on the poles serve as receivers and the mobile robot serves as a transmitter, and all ultrasonic sensors are integrated with their Zig-Bee modules. By the sequential ultrasonic signal transmission between the robot and the poles, the ultrasonic sensors on the poles can then measure the time-of-flight (TOF) without interference to calculate the distance between the receiver and transmitter ends. According to an established two-dimensional coordinate model, position of the robot can be obtained based on the distance measurements. Thanks to Zig-Bee modules, position information of the robot can be instantly conveyed to a remote PC for monitoring the robot and path planning. Extensive experiments conducted have shown a satisfactory accuracy of the coordinates of the mobile robot can be obtained via the proposed localization scheme.