Electronic Nose Sensing in Agriculture

Transcription

1 Electronic Nose Sensing in Agriculture A Feasibility Study dr. ir. Aleksandar Andreski Dept. of NanoPhysics Interfaces Saxion University of Applied Sciences

2 Contents Application: detecting rot in potato storage Piezo-microcantilevers as electronic nose Preliminary Results and Future Work Project Participants Partners

3 Potato Storage Matching supply & demand requires storage on site Storage time ~1 year New harvest is still wet and vulnerable to rot Rot spreads very quickly First few weeks are critical è Monitoring is needed

4 Potato Storage Systems Warehouses are ventilated with active cooling Control of Temperature (and partially Humidity) C0 2 is also monitored 30% losses without warehousing system Big problem in e.g. developing world

5 Potato Storage Systems Multiple T and RH Sensors Automatic Recipes Energy Minimization Can Track Batch from Field to Customer

6 Potato Storage Systems Add one more sensor E-Nose Monitors gas composition in real time Early warning for disease Challenges (specs): Ppm detection limit T and RH compensated Position, sampling?

7 E-Nose Working Prnciple Human olfactory system e-nose: array of non-specific, cross-reactive sensors combined with an information processing system Many Sensors of Some Specificity Literature examples Complex Analyte Statistical Analysis PC2: 24.5% Principal component analysis 4 Q4 Propanol 2 Cyclohexanon Q6 0 Q3 Q2 Anisole Q7 Q8 Q5-2 Toluene Q PC1: 64.6% 2

8 Olfactory Detection of Rot Detection of Potato Storage Disease via Gas Analysis: A Pilot Study Using Field Asymmetric Ion Mobility Spectrometry Massimo Rutolo 1, *, James A. Covington 1, John Clarkson 2 and Daciana Iliescu 1 Sensors 2014, 14, ; doi: /s Many Literature Studies dating back to 1990s Different Types of Rot Different Biomarkers VOC Fingerprinting This line is selected for highest observability. Gas ions mobility spectra Statistical analysis (PCA) and Clustering

9 Olfactory Detection of Rot Detection of Potato Storage Disease via Gas Analysis: A Pilot Study Using Field Asymmetric Ion Mobility Spectrometry Massimo Rutolo 1, *, James A. Covington 1, John Clarkson 2 and Daciana Iliescu 1 Sensors 2014, 14, ; doi: /s Many Literature Studies dating back to 1990s Different Types of Rot Different Biomarkers VOC Fingerprinting

10 Olfactory Detection of Rot The development of a sensor system for the early detection of soft rot in stored potato tubers To cite this article: B P J de Lacy Costello et al 2000 Meas. Sci. Technol Many Literature Studies dating back to 1990s Different Types of Rot Different Biomarkers VOC Fingerprinting VOC Biomarkers Different positions in a crate

11 MicroCantilever Principle Sorption changes Mass & Spring constant è Resonant f shift

12 Δf f = 1 2 Δk k Δm m WATER ACETONE ETHANOL Saturation (%) Saturation (%)

13 Piezoelectric MEMS cantilever with PZT Layer Silicon SiO 2 Pt Photoresist PZT Insulation Gold Pyralin 200um

14 SURFACE MASS LIMIT OF DETECTION SMLOD * Thermomechanical Noise Limit * In practice, limit is due to electronic noise A=Displacement amplitude Device Resonance Quality Surface Minimum SMLOD DMMP DMMP area Frequency factor sensitivity Relative Concentration Concentration Device & Ref Frequency resolution resolution deviation (measured) (estimated) (μμ C ) (MHz) (cμ C. l 1 ) (Hl. μμ C ) (ppb) (ppb) FBAR [122] (b) (b) (b) (c) 60 (e) SAW [34] (b) 158 (c) (b) 87 (b) 42 CMR [123] (b) (b) (d) 0.35 (e) CMUT [124] (b) (b) (d) 3 (e) Nanocantilevers [50] μ-cantilevers [125][126] Table (b) (b) Paul Ivaldi. Modeling, fabrication and characterization of resonant piezoelectric nano mechanical systems for high resolution chemical sensors. Micro and nanotechnologies/microelectronics. Université de Grenoble, English. <NNT : 2014GRENT109>. <tel > (b) (b) (c) PZT offers high transduction factors Higher electronic amplitudes Less electronic noise in practice (d) 2 (e) (e)

15 Readout and Measurements Mechanical resonance Transduced by PZT parasitic Phase-Lock-Loop Resonator Interface + Tracks resonant f automatically + mhz noise with these sensors - Complex to implement in product - Suffers from C P variation Z m Low Piezo-transduction Z m >> Z p weak resonance High Piezo-transduction stonger resonance peaks

16 Readout and Measurements Mechanical resonance Transduced by PZT parasitic Phase-Lock-Loop Resonator Interface + Tracks resonant f automatically + mhz noise with these sensors - Complex to implement in product - Suffers from C P variation

17 Readout and Measurements Frequency noise [mhz rms] RMS readout noise as a function of readout speed Δf f (50 ppb) k PLL Bandwidth [Hz] Δm m eff = 2 Δf f Δm S min 1 ag µm 2 Practical SMLOD (can be lower if we measure slower)

18 Readout and Measurements: ACETONE Cantilever C10 (PEI), Flow of 0.1L/min, PLL Target bandwidth = 60Hz Two Cantilevers Simulatneously, Flow of 50mL/min PLL Target bandwidth 10Hz ppm 0 ppm 0 ppm ppm Resonance freq. [Hz] Shift [mhz] 500 ppm time [s] 1000 ppm 11Hz (11mHz/ppm) Resonant frequency [Hz] ~100ppm ON/OFF Sensor with PEI layer Sensor with PAA layer Noise x10 (unexplained) ppm Time [s] Time [s]

19 Conclusions and Future Work Detection of potato rot via E-nose is present in literature and prior work. Piezo-cantilevers with PZT have: a low theoretical SMLOD good practical properties (high signals) Measurements so far are not conclusive Drift is very high and unpredictable Noise increases with more cantilevers active Sensitivity to parasitics with current readout scheme (PLL) Future Work: Sensitive Layers Layer Deposition Readout Scheme

20 Many Thanks to: Ruud Steenwelle Albert van Hoorn and all students that contributed greatly: Sameh, Bas, Steven, Jorrik, Casper, Ferry. Questions?