Introduction to Information

Transcription

1 Introduction to Information Technology: Measurements from Earth to Mars C. S. Campbell Decagon, Devices, Inc. Pullman, WA

2 CSC1 Why do we make measurements? We are always curious to learn more about what surrounds us Understand how things work Predict what will happen in the future Learn what has happened in the past

3 スライド 2 CSC1 add picture of night-time sky Colin S. Campbell, 2009/07/08

4 CSC2 Our inspiration My father s family are farmers in dry area of USA Gave us a passion for Measuring water to grow better crops Learning more about the physical environment How do things like heat and water flow from the soil to the plant and into the atmosphere?

5 スライド 3 CSC2 Add picture of Juniper or sage brush area with farm Colin S. Campbell, 2009/07/08

6 How do we make measurements? A difference in electrical potential produces an electromagnetic (EM) field Poles of a magnet show field lines in iron fillings

7 Typical Capacitor Capacitor Dielectric Material Positive Plate Negative Plate Electromagnetic Field

8 Dielectric Theory: How it works Components of soil Material Dielectric Charge Permittivity stored in EM Field Air 1 Low Soil Minerals 3-7 Low Organic Matter 2-5 Low Ice 5 Low Water 80 High Organic Matter Air Water Soil 1% 15% 35% 50% Small change in water = large change in stored charge

9 Example: How Soil Sensors produce EM Field (measure water) 2 cm Sensor (Side View) 1 cm 0 cm EM Field

10 Getting to Water Content Charging of capacitor directly related to dielectric Sensor circuitry converts capacitor charge to an output of voltage or current Measurement device reads and interprets output Sensor output is calibrated to water content using the volumetric water content method discussed earlier Vol umetric Water Co ontent (θ) FDR Sensor Output

11 Decagon goes to Mars Heat storage in soil is important for many reasons Renewable energy from heating and cooling with soil as the reservoir Contributes to available energy for plant evaporation Correlates with soil moisture Decagon makes needle sensor to measure thermal conductivity Soils ability to transfer heat Interplanetary scientist saw instrument at Interplanetary scientist saw instrument at tradeshow

12 Water On Mars

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14 The Phoenix Scout Mission 2007 (Landed May 25, 2008) Phoenix goal is to understand the provenance of the high latitude ice deposits seen by Odyssey, and to determine whether the icy region is compatible with past or present life. Phoenix will Search for evidence of past or episodic liquid water Search for subsurface ice and clues to its origin Characterize present-day climatic processes Determine the habitability of the excavated zone by seeking energy sources and toxic constituents

15 More on Phoenix Location: Northern polar regions Type: Lander (remains in one place) Instrumented for chemical and physical analysis of Martian soil (regolith) Robot arm scoop for exposing trench, sampling soil, and probing

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17 Thermal and Electrical Conductivity Probe (TECP) Attachment to Robot Arm

18 Observations On Frozen Soil Some fraction of the water in frozen soil is always in the liquid phase (frozen soil is a mixture of mineral, ice, liquid water, and air) When an ice phase is present, the water potential is completely determined by temperature (1.2 MPa/C)

19 Thermal and Electrical Conductivity Probe (TECP) General Overview Regolith (Soil) thermal properties Soil temperature Thermal conductivity it Volumetric heat capacity Soil electrical properties Dielectric constant Electrical conductivity Atmospheric properties Vapor pressure Wind speed

20 Mission animation

21 Phoenix Launch to Mars

22 Pictures courtesy of NASA/JPL-Caltech/University of Arizona

23 Picture under the Lander Pictures courtesy of NASA/JPL-Caltech/University of Arizona

24 Exposed ice under the lander Pictures courtesy of NASA/JPL-Caltech/University of Arizona

25 Scoop Trenches

26 TECP on Mars

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28 Helping the farmer on Earth Fresh water is essential for life Contamination and scarcity of fresh water are issues all over the world Israel is a good example where fresh water is so scarce that people cannot water their gardens this year Farms and gardens could help save significant amounts of water Measurement is the key to turning the water on or off

29 Adding soil moisture control to watering Significant ifi water savings can be gained by controlling irrigation water In the middle of US, one homeowner saved 70% of irrigation water with soil moisture sensor Inexpensive sensors are the problem Most sensors are too expensive or do not work The same technology as flew to Mars can help homeowner Successful implementation ti requires more expensive water or governement subsidies

30 Controlling the water on a Potato Farm Commercial potato farm irrigating with processing water Recycles nitrogen and other plant nutrient Reclaimed water must not reach groundwater Experimental setup ECH 2 OEC5 EC-5 water content sensors installation in pit side wall at 3 depths Monitor inside id and below root zone Track water use

31 Sandy loam water content cm Sensor cm Sensor Volume etric Water Content (m 3 m 3 ) cm Sensor Applied Water Irrigation (mm) 0 4/1/2007 5/2/2007 6/2/2007 7/3/2007 8/3/2007 9/3/2007 0

32 Subset of sandy loam data cm 30 cm 60 cm Applied Water mm Vo olumetric Wa ater Conten t (m 3 m -3 ) Irri igation (mm) 0 0 6/22/2007 6/29/2007 7/6/2007 7/13/2007 7/20/2007 7/27/2007

33 Conclusion Making instrumentation can be both exciting and rewarding Only through innovative decides can we understand more of our world Solving the world s water problems is essential for the sustainability stainabilit of Earth s population