Next Article in Journal
Estimation of Biomass and Canopy Height in Bermudagrass, Alfalfa, and Wheat Using Ultrasonic, Laser, and Spectral Sensors
Previous Article in Journal
Research on Odor Interaction between Aldehyde Compounds via a Partial Differential Equation (PDE) Model
Article Menu

Export Article

Open AccessArticle
Sensors 2015, 15(2), 2902-2919;

Testing Accuracy of Long-Range Ultrasonic Sensors for Olive Tree Canopy Measurements

Dpto. de Ingeniería Rural, Área de Mecanización y Tecnología Rural, Universidad de Córdoba, Córdoba 14005, Spain
Dpto. de Ingeniería Aeroespacial y Mecánica de Fluidos, Área de Ingeniería Agroforestal, Universidad de Sevilla, Ctra. de Utrera, km 1. 41013 Sevilla, Spain
Author to whom correspondence should be addressed.
Received: 22 December 2014 / Revised: 16 January 2015 / Accepted: 22 January 2015 / Published: 28 January 2015
(This article belongs to the Section Physical Sensors)
Full-Text   |   PDF [5475 KB, uploaded 28 January 2015]   |  


Ultrasonic sensors are often used to adjust spray volume by allowing the calculation of the crown volume of tree crops. The special conditions of the olive tree require the use of long-range sensors, which are less accurate and faster than the most commonly used sensors. The main objectives of the study were to determine the suitability of the sensor in terms of sound cone determination, angle errors, crosstalk errors and field measurements. Different laboratory tests were performed to check the suitability of a commercial long-range ultrasonic sensor, as were the experimental determination of the sound cone diameter at several distances for several target materials, the determination of the influence of the angle of incidence of the sound wave on the target and distance on the accuracy of measurements for several materials and the determination of the importance of the errors due to interference between sensors for different sensor spacings and distances for two different materials. Furthermore, sensor accuracy was tested under real field conditions. The results show that the studied sensor is appropriate for olive trees because the sound cone is narrower for an olive tree than for the other studied materials, the olive tree canopy does not have a large influence on the sensor accuracy with respect to distance and angle, the interference errors are insignificant for high sensor spacings and the sensor’s field distance measurements were deemed sufficiently accurate. View Full-Text
Keywords: ultrasonic sensor; canopy characterization; olive tree; sensor accuracy; sensor interference ultrasonic sensor; canopy characterization; olive tree; sensor accuracy; sensor interference

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Gamarra-Diezma, J.L.; Miranda-Fuentes, A.; Llorens, J.; Cuenca, A.; Blanco-Roldán, G.L.; Rodríguez-Lizana, A. Testing Accuracy of Long-Range Ultrasonic Sensors for Olive Tree Canopy Measurements. Sensors 2015, 15, 2902-2919.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top