transducers & general applications. automotive & off-road braking systems, common fuel rail,...
Post on 19-Dec-2015
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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)
• 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)
• 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
• 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