Implementation of Implementation of physical Sensorsphysical Sensors

Jesse McVaneyJesse McVaney

BME281 URIBME281 URI

Modern SensorsModern Sensors

1917 - Langevin uses piezoelectric 1917 - Langevin uses piezoelectric effect to create sonar.effect to create sonar.

1925 – Dr. Tsuji develops the first 1925 – Dr. Tsuji develops the first combustible gas monitor.combustible gas monitor.

1958 – Kilby develops first integrated 1958 – Kilby develops first integrated circuit for Texas Instruments making it circuit for Texas Instruments making it possible to significantly reduce the possible to significantly reduce the size of circuits.size of circuits.

Sensor TypesSensor Types

Motion/ PositionMotion/ Position ForceForce TemperatureTemperature VibrationVibration Current/ ResistanceCurrent/ Resistance LightLight ChemicalChemical

ExamplesExamples

www.sparkfun.com

Homemade SensorsHomemade Sensors

StandardsStandards

Sensors may have to comply with Sensors may have to comply with strict standards to be implemented strict standards to be implemented for medical use.for medical use.

Degree of accuracy, maintenance Degree of accuracy, maintenance schedule, material all factor in to how schedule, material all factor in to how a sensor may be implemented.a sensor may be implemented.

American National Institute Standard American National Institute Standard code ANSI Z540 covers these code ANSI Z540 covers these requirementsrequirements

Instruments may have to undergo Instruments may have to undergo periodic calibrations (Annual, periodic calibrations (Annual, monthly, Case per Case)monthly, Case per Case)

Calibrations may require a standard Calibrations may require a standard at least ten times as accurate as the at least ten times as accurate as the instrument under test (Fluke)instrument under test (Fluke)

Implantable sensors may need to be Implantable sensors may need to be constructed of certain materials to constructed of certain materials to avoid toxicity, allergic reaction, or to avoid toxicity, allergic reaction, or to withstand the environment they are withstand the environment they are operating in.operating in.

CostCost

Prices vary widely depending on the Prices vary widely depending on the material, intended use and liability material, intended use and liability coverage.coverage.

ANSI codes are meant to protect ANSI codes are meant to protect patients but may consequently make patients but may consequently make some procedures or equipment some procedures or equipment unaffordable. unaffordable.

FutureFuture

Less expensive synthetic material.Less expensive synthetic material. Clearer transmission signalsClearer transmission signals Faster sample ratesFaster sample rates Smaller implantable/wearable Smaller implantable/wearable

devicesdevices Fewer Calibrations needed.Fewer Calibrations needed.

Sources citedSources cited Image 08880-03-L <www.sparkfun.com/products/8880>Image 08880-03-L <www.sparkfun.com/products/8880> Image 08685-03-L <www.sparkfun.com/products/8685>Image 08685-03-L <www.sparkfun.com/products/8685> Image 09265-1 <www.sparkfun.com/products/9265?>Image 09265-1 <www.sparkfun.com/products/9265?> Fluke: "Why calibrate test equipment?“. FLUKE Corporation, 2004.Fluke: "Why calibrate test equipment?“. FLUKE Corporation, 2004.