Non-Invasive Measurement of Material Properties Principal Investigators: Alexander Mamishev, Ann Mescher Graduate Research Assistants: Kishore Sundara-Rajan, Xiaobei Li, Michael Hegg, and Anil Ogale Sensors, Energy, and Automation Laboratory Department of Electrical Engineering University of Washington

SEAL, EE Department, University of Washington Outline n Introduction n Experimental Results ä Paper Pulp ä Pharmaceutical Products ä Food Products ä Composite Materials ä Plastics n Future work n Conclusions

Introduction

SEAL, EE Department, University of Washington Dielectrometry Research Directions in CPAC / SEAL projects ApplicationFundingCollaboratorStatus (0-10) Moisture in organic products CPACKraft7 Moisture in paper pulp Metso through CPAC Metso5 Curing of composite materials AFOSR, CPAC matching Boeing2 Physical properties of pharmaceutical samples CPAC Wyeth, Aventis, BMS(?) 1 Physical properties of plastics samples GE Plastics (?)1

SEAL, EE Department, University of Washington Fringing Field Interdigital Sensor n For a semi-infinite homogeneous medium placed on the surface of the sensor, the periodic variation of the electric potential along the X-axis creates an exponentially decaying electric field along the Z-axis, which penetrates the medium.

SEAL, EE Department, University of Washington Multiple Resolution Levels n Non-destructive, one-sided access. n Through varying excitation patterns, multiple levels of proximity are possible. n In-plane resolution is proportional to proximity sensing depth.

SEAL, EE Department, University of Washington Sensing Possibilities n Fringing electric fields can detect various characteristics of a sample.

SEAL, EE Department, University of Washington Di-SPEC n Application specific sensor design n In-house designed multi channel data acquisition circuit. n Custom designed user interface. n Integrated real time data processing units. n Modular software architecture.

Recent Experimental Results Paper Project

SEAL, EE Department, University of Washington Experimental Setup n Pulp is blended using a blender to a consistency of a suspension. n Sensor is attached to the outer side of the base of an acrylic tray. n A guard plane is placed underneath the sensor electrodes to provide shielding from external electric fields.

SEAL, EE Department, University of Washington Two Component Pulp n Average normalized error of 1.7%, 2.1% being state of the art.

SEAL, EE Department, University of Washington Common Additives n Whitening Agent ä Titanium dioxide n Filler ä Clay ä Calcium carbonate n Coloring pigments n Sizing and Retention aids

SEAL, EE Department, University of Washington Three Component Pulp

SEAL, EE Department, University of Washington Parameter Selection Algorithm n Automatic selection of parameters and constants based on training data set. n The accuracy of the estimation is dependent on the quality of the training data set. n Two interlinked algorithms operating in parallel ä Learning Algorithm ä Estimation Algorithm

SEAL, EE Department, University of Washington Sample Output from Algorithm n 2 sets of data were used to train the algorithm.

Recent Experimental Results Pharmaceutical Products

SEAL, EE Department, University of Washington Experimental Setup n Fringing Electric Field Sensor with wavelength of 500 microns was used. n Measurements were made using Fluke manufactured RCL meter (Model: PM 6304). n Multiple tablets were placed on the sensor at a time.

SEAL, EE Department, University of Washington Coating Thickness

SEAL, EE Department, University of Washington Drug Signature

SEAL, EE Department, University of Washington API Concentration n Monotonic dependence exists between capacitance and drying time. n One-to-one mapping can be established between capacitance and drying time to calibrate the sensor. n Monotonic dependence exists between capacitance and drying time. n One-to-one mapping can be established between capacitance and drying time to calibrate the sensor.

Recent Experimental Results Cookie Project

SEAL, EE Department, University of Washington New simulation instruments n The moisture and temperature control chamber is used to monitor the aging process of samples. n The table on the right has controllable rotational motion. n The platform has precision controllable vertical motion. n The table can be used as scanner to measure samples at different positions.

SEAL, EE Department, University of Washington Labview Control Interface for the Rotating Table

SEAL, EE Department, University of Washington The Effect of Temperature – I n Measurements of bagel samples placed inside the chamber at different temperature levels. n Capacitance goes down with increasing frequency.

SEAL, EE Department, University of Washington The Effect of Temperature – II n Conductance goes up with increasing frequency.

SEAL, EE Department, University of Washington Simulation of the Aging Process – I n Chamber ambient temperature is set to and maintained at 85 ºF. n Chamber ambient humidity is set to 85%. n Bagel samples are placed inside the chamber. n Electrical measurements are collected when sample moisture content varies till it reaches equilibrium with the environment.

SEAL, EE Department, University of Washington Simulation of the Aging Process – II

SEAL, EE Department, University of Washington Simulation of the Aging Process – III

SEAL, EE Department, University of Washington Multi-Channel FEF Sensor Design n Figures of merits ä Signal strength ä Measurement sensitivity ä Dynamic range ä Penetration depth ä Robustness to disturbance factors n Major design concerns ä Choice of sensor substrate and electrode material ä Choice of sensor geometry ä Size limitations ä Number of channels ä The position and geometry of the back plane Effect of substrate thickness

Recent Experimental Results RTM Project

SEAL, EE Department, University of Washington Transparent Film Sensor n ITO (indium tin oxide) sputtered film on PET (polyester) substrate n Can be integrated in FEF or parallel-Plate configuration n Transparency allows for coupling with IR sensor n Flexibility allows for complex geometry applications

SEAL, EE Department, University of Washington Spectroscopy Analysis

SEAL, EE Department, University of Washington Fill Front Position Detection n Independent measurements of fill-front position by sensors and camera show good correspondence.

SEAL, EE Department, University of Washington Prototype Sensor Design

Recent Experimental Results Plastics

SEAL, EE Department, University of Washington Moisture Absorption Initial Measurement After 2 hrs in Water After a Time Delay Data Interpretation

SEAL, EE Department, University of Washington Future Work n Testing at manufacture sites (food, possibly paper) n Real-time imaging and profiling (all applications) n Increased sophistication of parameter estimation algorithms (all applications) n Demonstration of real-time feedback process control (composites, possibly food) n Further exploration of promising applications (pharmaceuticals, possibly polymers) n Better integration with analytical chemistry research in CPAC, standardization and sensor fusion

SEAL, EE Department, University of Washington Publications n K. Sundara-Rajan, L. Byrd, and A. V. Mamishev, "Estimation of Moisture Content in Paper Pulp Containing Calcium Carbonate Using Fringing Field Impedence Spectroscopy," Appita Journal, (submitted) n K. Sundara-Rajan, L. Byrd, and A. V. Mamishev, "Estimation of Moisture Content in Paper Pulp Containing Titanium Dioxide Using Fringing Field Impedance Spectroscopy," TAPPI Journal, (submitted) n K. Sundara-Rajan, L. Byrd, and A. V. Mamishev, "Moisture Measurement in Paper Pulp Using Fringing Field Dielectrometry," IEEE Sensors Journal, (submitted) n K. Sundara-Rajan, L. Byrd, and A. V. Mamishev, "Estimation of Moisture Content in Paper Pulp Containing Titanium Dioxide Using Fringing Field Impedance Spectroscopy," Tappi Spring Conference, Atlanta, (submitted) n K. Sundara-Rajan, L. Byrd, and A. V. Mamishev, "Estimation of Moisture Content in Paper Pulp Containing Calcium Carbonate Using Fringing Field Impedance Spectroscopy," 58th Appita Annual Conference, Cannberra, Australia, (submitted) n K. Sundara-Rajan, X. Li, N. Semenyuk, and A. V. Mamishev, "Moisture Measurement in Paper Pulp Using Fringing Field Impedance Spectroscopy," IEEE Sensors Conference, Toronto, Canada, October 2003.

SEAL, EE Department, University of Washington Publications (Cont’d) n X. Li, A. S. Zyuzin, and A. V. Mamishev, "Measuring Moisture Content in Cookies Using Dielectric Spectroscopy," IEEE CEIDP Conference, Albuquerque, New Mexico, October n X.Li, C, Zrybko, R. Magaletta, and A. V. Mamishev “Dielectrometry Based Sensing of Moisture Content Distribution in Cookie Dough,” accepted by IFT International Food Safety and Quality Control Conference and Expo (2003). n X. Li, A. S. Zyuzin, and A. V. Mamishev “Impedance Spectroscopy Sensing of Moisture Content in Cookie Dough,” submitted to IEEE Transactions on Dielectrics and Electrical Insulation. n B.Minaie, W. Li, J. Gou, Y. Chen, A.V. Mamishev, and A. Mescher, "Direct Adaptive Control of Resin Transfer Molding," SAMPE 2003, Long Beach, USA, May, n A. A. Ogale, M. Hegg, A. Mescher, A. V. Mamishev, and B. Minaie “Fill Front Detection Using Dielectric Sensors in Resin Transfer Molding Process,” accepted by ICCE (International Conference on Composite/Nano Engineering) 2003.

SEAL, EE Department, University of Washington n Undergraduate Research Assistants  Leslie Byrd II  Nick Semenyuk  Cheuk Wai Mak  Patrick Aubin  Gio Hwang  Alexei Zyuzin  Chika Kato  Nanaul Lwai  Yu Cheung Tse  Victor Loui Acknowledgements

SEAL, EE Department, University of Washington n We are grateful to Drs. Robert Magaletta and Carol Zrybko (Kraft Foods), Mahendra Muhnidasa and Seyhan Nuyan (Metso Automation), William Herb (Boeing), and Gideon Oenega (Wyeth) for their help and advice in the most recent stages of this project. n Matching support from AFOSR and NSF is gratefully acknowledged. n Additional funding is also provided by Metso Automation and Kraft Acknowledgements