Classification of plastic materials using machine-learning algorithms and microwave resonant sensor

Abstract

The identification of different plastic materials in pellet form using a microwave negative-order-resonance sensor along with the evaluation of classification algorithms from machine learning is presented in this paper. Operation of the sensor is within the unlicensed ISM 2.5 GHz band, and identification of the materials is based on the measured resonant parameters from the sensor. Several classifiers are used to process the resonant parameters having uncertainty factors involved in pellet measurements (air gaps, pellet positions, dimensions and shapes), and performance comparison between the algorithms is carried out in terms of accuracy in the classification. Moreover, the presented measurement method is proposed as a fast, non-destructive, and low-power consumption way to identify plastic raw materials using a low-profile circuit having a high potential of being used in industrial processes.

KEYWORDS:

• Classification algorithms
• microwave sensors
• measurement uncertainty
• plastics
• resonant sensors

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Dania Covarrubias-Martínez

Dania Covarrubias-Martínez Received the B.Sc. degree in electronics engineering from the Universidad Autónoma de Baja California, UABC, Ensenada, Mexico, in 2004 and the M.Sc. degree in electronics from the Centro de Investigación Científica y de Educación Superior de Ensenada, CICESE, Mexico, in 2007, where she is currently pursuing the Ph.D. in electronics.From 2008 to 2012, she was a technical engineer at Cenam, Querétaro, Mexico. From 2013 to 2017, she collaborated in setting up a calibration laboratory at CIDESI, Tijuana, Mexico and, participated in the installation maintenance of radar scatter meters at IIO, Ensenada, Mexico. From 2018 to 2019, she was an RF filter designer at Lark-Engineering in Tijuana, Mexico. Her research interests include designing, modeling, characterization, and implementing RF devices and circuits.

Humberto Lobato-Morales

Humberto Lobato-Morales (S’05–M’14–SM’19) obtained the B.Sc. and M.Sc. degrees in electronics engineering from the Universidad de las Américas-Puebla, UDLAP, Puebla, Mexico, in 2006 and 2008, respectively, and Ph.D. degree in electronics from the Instituto Nacional de Astrofísica, Óptica y Electrónica, INAOE, Puebla, Mexico, in 2013. From 2011 to 2012, he was a Visiting Student with the Electrical Engineering Department, University of California at Los Angeles, UCLA. In 2013, he joined the Centro de Investigación Científica y de Educación Superior de Ensenada, Baja California, CICESE, Mexico, as Assistant Professor with the Department of Electronics and Telecommunications; since 2020 he raised to Associate Prof. His research interests include microwave sensors, filters, multiplexers, antennas and characterization of materials at microwave frequencies. Dr. Lobato-Morales was a recipient of the IEEE MTT-11 Creativity and Originality in Microwave Measurements Award in 2010 and the ROG Most Innovative Design Award in 2012.

Juan M. Ramírez-Cortés

Juan M. Ramirez-Cortes (M’92-SM’04) received the B.Sc. degree from the National Polytechnic Institute, Mexico, the M.Sc. degree from the National Institute of Astrophysics, Optics, and Electronics (INAOE), Mexico, and the Ph.D. from Texas Tech University, all in electrical engineering. He is currently a Titular Researcher at the Electronics Department, INAOE, in Mexico. He is member of the Mexican national research system (SNI), level 2. He currently serves as Executive Vice President of the IEEE Instrumentation and Measurement Society. His research interests include digital signal processing, instrumentation, biometric systems, neural networks and pattern recognition.

Germán A. Álvarez-Botero

Germán A. Álvarez-Botero (S’03-M’14-SM’19) received the Ph.D. degree from the National Institute for Research on Astrophysics, Optics, and Electronics (INAOE), Puebla, Mexico. He was a postdoctoral researcher with the RF Research Group, Universidade Federal de Santa Catarina (UFSC), Florianópolis, Brazil; with the High-Frequency Electronics and Telecommunications Research Group (CMUN), Universidad Nacional de Colombia, Bogotá, Colombia; and with the Microwave Components Group (MCG), Universidad Pública de Navarra (UPNA), Pamplona, Spain. In 2018 he was a visiting researcher Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Toulouse, France. He is currently a Titular Researcher at the Electronics and Telecommunications Department, Center for Scientific Research and Higher Education of Ensenada (CICESE), Mexico. His research interests include the design, characterization, and modeling of active and passive components for RF/Microwave circuits and systems.