Accurate Estimation of Airborne Ultrasonic Time-of-Flight for Overlapping Echoes

Sensors

Esther G. Sarabia¹  Jose R. Llata²  Sandra Robla²  Carlos Torre-Ferrero² 

[1] Electronic Technology and Automatic Systems Department, School of Industrial and Telecommunications Engineering, University of Cantabria, Avda. de Los Castros s/n 39005, Santander, Spain;

关键词: airborne ultrasounds;    accurate time of flight;    dynamic response model;    hidden echo detection;    hidden echo time of flight;    overlapping echoes;    robotics;    autonomous navigation;   

DOI  :  10.3390/s131115465

来源: mdpi

【 摘 要 】

In this work, an analysis of the transmission of ultrasonic signals generated by piezoelectric sensors for air applications is presented. Based on this analysis, an ultrasonic response model is obtained for its application to the recognition of objects and structured environments for navigation by autonomous mobile robots. This model enables the analysis of the ultrasonic response that is generated using a pair of sensors in transmitter-receiver configuration using the pulse-echo technique. This is very interesting for recognizing surfaces that simultaneously generate a multiple echo response. This model takes into account the effect of the radiation pattern, the resonant frequency of the sensor, the number of cycles of the excitation pulse, the dynamics of the sensor and the attenuation with distance in the medium. This model has been developed, programmed and verified through a battery of experimental tests. Using this model a new procedure for obtaining accurate time of flight is proposed. This new method is compared with traditional ones, such as threshold or correlation, to highlight its advantages and drawbacks. Finally the advantages of this method are demonstrated for calculating multiple times of flight when the echo is formed by several overlapping echoes.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.