Transducers

&

General Applications

Automotive &

Off-road

Braking systems, common fuel rail, fuel tank level, auto crash testing, car alarms,

tire pressure, vehicular safety

Medical

Disposable blood pressure sensors, respirators, ventilators, sleep apnea, infusion pump, pacemaker, electronic stethoscope, renal and blood separation pressure sensors, ambulatory medical devices

Commercial Building

Air duct flow, elevator load detection

Business & Retail Equipment

Beverage dispensing, security protection, ATM banknote thickness, coin counting and validation

AppliancesWashing machine level and load imbalance, microwave food weight, touch-sensitive controls

Solutions by Industry

Traffic & Mass Transit

Traffic counters, weigh-in-motion, toll collection, train brakes and controls

Power & Utilities

Tank liquid level, gas turbines, nuclear power plant controls, water purifiers, flow meters, power generation controls

Industrial

Machinery

Manufacturing process controls, valve and flow controls, compressor output, paint sprayers, stamping machine load cells

Consumer Electronics

E-Pen digitizer, musical instrument pickups, pedometer, bathroom scale, directive speakers, sports scoring, parking meter

Aerospace & Defense

Flight controls, missile firing/guidance, fuel/oil pressure, air traffic avoidance, safe weapons firing, fence/perimeter security

Solutions by Industry

Pumps

Compressors

Railroad

Diesel engines

Paint sprayers

Refrigeration

Chillers

Automotive Test equipment

Fertilizer spraying

Refrigeration

Diesel enginesAirlesspaint sprayers

Application of micro-fused Sensors

• Micro-Electromechanical Systems (MEMS)– MEMS design and simulation– Micromachining (Silicon and glass);

wafer processing (strategic partnerships)– Packaging, test, calibration

• Pressure Sensors– Die or packaged, absolute & gauge– Metal isolated (vacuum/oil filled)

• Accelerometers– 1-2 axis; piezoresistive transduction– 3-layer structure (dampening, shock protection)

• Development Efforts– Flow, Hydrogen, Humidity Sensors– Small, low G accelerometer

Pressure Sensors

Mass Accelerometer

Sensor Technology (MEMS – IC Sensors)

Disposable blood pressure Atomic force microscope

Infusion pumps

IC Sensors Application

• Linear Displacement: LVDT, LVIT, LCIT

– Non-contact, electromagnetic device

– Infinite resolution (sub-micron;2 nm applications)

– Excellent null repeatability

– Rugged designs for harsh conditions

– Variety of sizes (>1” to 12”) and options

(AC/DC, high temp, compensation, etc.)

– Standard or custom engineered

– Gage heads and readout systems

– Large installed base

• Rotary Displacement: RVIT, RVDT, RSYN, R120LC

– Non-contacting design means virtually infinite rotational life

– Infinite resolution

– 360 degree rotation

– Variety of standard sizes and options or custom engineered

Schaevitz Linear andRotary Sensors

Sensor Technology (Linear/Rotary Displacement)

Industrial Actuators

Sub-sea Operations

lifts

Wheel Alignment

Sensor Technology (Linear/Rotary Displacement)

• Piezoelectric Polymer Characteristics– Transmitter or receiver– Wide dynamic range (nano strain – 109 Newtons)– Broad frequency response (0.1 Hz – 100 MHz)– Die cut into any shape– Spun into cable– Patterned metallizations

(electrodes, sputtering)– Flexible, robust, inert, biocompatible

• Applications– Electronic stethoscope– Ultrasonic pen digitizer– Anti-tamper sensor– Traffic cable (weigh-in-motion, speed, toll)– Security fencing/cable– Activity monitor– Vibration sensor (appliances, alarms)– Sonar– Dynamic impact load cell– Ultrasonic directional speakers– Microphones (musical instrument pickup)

Piezo converts mechanical strain to voltage…and changes dimension with applied voltage

PCMCIA Anti-tamper Panel

Sensor Technology (Piezoelectric Film)

Vibration

Traffic

Remote reading water meter

Piezoelectric Sensor Application

• Capacitive Tilt Sensors– Single and dual axis– 0.1 degree resolution– Temperature compensated

• Fluid Level Sensor– Spring-mounted float produces

readings through a Hall Effect device– Oil, transmission fluid for off-road vehicles

• Duralith Keypads and Membrane Switches– Advanced graphics and durability– Applications include medical devices, point-of-sale,

hand-held scanners, equipment control panels• Value-Added Assembly

– Highly cost-competitive, one-stop approach– Housings and subassemblies for medical equipment

consumer electronics, automotive components, etc.

Dual-axis Tilt Sensor

Disposable Blood Pressure Sensor Assembly

Sensor Technology (Other Applications)

• Polyvinylidene Fluoride, PVF, PVDF

• Chemical Makeup: CH2-CF2 Polymer Chain

• Engineering Plastic Sold under the Trade Name, Kynar®– Rugged– Chemically Inert– Electrical Insulator

• Uses:– Lining of Chemical Tanks/Pipes– Wire Wrap Insulation– Paints to Protect Steel Structures– Capacitor Film– “Unleaded Gasoline” Labels

What is PVDF?

• High purity, electronics-grade PVDF resin pellets

• Extrude to form relatively thick film

• Stretch (draw ratio 5:1) to orient the film

• Polarize under intense electric field (“poling”) - continuous corona process

• Anneal to achieve temperature stability

• Electrodes: screen-print or vacuum-metallize

• Laminate if required

• Die-cut, using steel-rule die

• Lead-attachment

Manufacturing Piezofilm

g31 -- stretch axisg32 -- transverse to stretch axisg33 -- thickness and polarization axis

Numerical Classification of Axes

• Dynamic transducer material - generates charge or voltage in response to change in stress or temperature

• Excellent linearity - charge/voltage is proportional to applied stress over very wide range

• Dynamic range: over 14 orders of magnitude (>280 dB) - from fC to mC, nV to kV

• High voltage sensitivity (20 x piezoceramic PZT)• Very broad bandwidth: from mHz to GHz• Low Q factor: can be < 1 in water, < 12 in air• High dielectric strength: up to 100 V/micron• flexible material, conforms to curved surfaces

1E-4 1E-2 1E0 1E2 1E4 1E6 1E8 1E10Frequency (Hz)

prototype accelerometer

LLF of ACH-04-08-05 accelerometer

LLF of ACH-01 accelerometer

typical imbalance signals

buried cable upper limit

fence-mounted cable

ultra-high-speed vibration

large-area digitizers

small digitizers

limit of air u/s microscope

u/s flowmeter

ink level switch

particle sizing probe

cryogenic tests

12 decade freq response of piezo film

Frequency Response of Piezo Film

• Temperature limited to < 125 deg C in most applications

• Piezo response varies over operating temperature band

• Wide tolerance on absolute sensitivity, capacitance

• Responds to all 3 axes simultaneously, and thermal

events

• Mechanical boundary conditions may influence output

• Relatively low capacitance, therefore high impedance

• May require careful shielding from EMI/RFI

• Material may not be soldered directly, needs wire/crimps

Limitations of Piezo Film

Piezo film can be modelled as a voltage source in series with a passive capacitance

When connected to a resistive load, the network becomes a high-pass filter

Equivalent Circuit of Piezo Film

Charge preamplifier Charge preamplifier

Interfacing to Piezo Film

• Accelerometers

• Actuators

• Contact microphones

• Flexible switches

• Hydrophones

• Impact/shock sensors

• Motion sensors

• PIR, pyroelectric or thermal sensors

• Piezo cable

• Traffic sensors

• Ultrasonic transducers

Applications of Piezo Film

• Calorie tracker• Fence security sensor• Gun recoil• High-speed pump monitor• Imbalance detection• Leak detection (water transmission)• Loudspeaker motional feedback• Ultracentrifuge bearing monitor• Vehicle motion detector

Applications (Accelerometers)

Accelerometer on subwoofers of new monitors

Each subwoofer is individually controlled, giving absolutely flat response to 20 Hz

Applications (Speaker Motional Feedback)

• Apnea sensors

• Blood pressure cuff microphone

• Coin validation sensor

• Glass-break sensor

• Guitar/acoustic instrument pick-up

• Stethoscope sensor

Applications (Contact Microphone)

Fishman Transducers produce high quality saddle-mounted pick-ups

Pick-ups for guitars, mandolins, harps, pianos…

Applications (Acoustic Guitar Pick-up)

Small element of piezo film as a contact microphone

Listening to the frequencies emitted by coins as they roll down a mechanism

Fake coins have completely different acoustic “signature”

Applications (Coin Validator)

LDTM-028K sensor

(laminated element with added mass)

as a simple accelerometer to detect load imbalance during spin cycle

Applications (Washing Machine Imbalance)

Applications (Ultrasonic Digitizers)

• Electronic white boards; piezo film based air ranging ultrasound transducers

• Retrofit market for 89 million existing white boards• Real time conference calls over the Internet

Mid-Range Surround

Sound Speaker

Applications (Speakers)

NO VOLTAGE APPLIED

VOLTAGE APPLIED