1 4 Operation, mechanisms and applications •Ken Gilleo PhD •ET-Trends LLC
Mar 26, 2015
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4 Operation, mechanisms and applications
•Ken Gilleo PhD•ET-Trends LLC
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Motion (actuators)Motion (actuators)• Actuators (“motors”)
Electrical (input) Thermal (usually from electrical)
Photonic (for MOEMS, OE)
• Sensors (output); usually electrical signals Capacitance Piezoresistive Resonant beam Electron tunneling Photonic Chemical Biological/biochemical
TYPES
POWER
Change/outputis caused bymechanicalmotion/force
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Actuator ClassesActuator Classes• Electrostatic/capacitive
Linear comb drive Rotary comb drive Horizontal parallel plates
• Electromagnetic Linear Rotary Integrated coils or external field Permanent or soft magnetic films
• Thermal Bimorph: dissimilar materials Shape memory alloys
• Pneumatic/hydraulic• Mechanical conversions/translations
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MEMS EnginesMEMS Engines
• Electrostatic; very efficient
• Thermal; easy to implement
• Electromagnetic, smaller
• Pneumatic
• Hydraulic
• Photoelectric (energy through fiber)
*Surface area is relatively high, mass is very low; surface effects are important
*Surface area is relatively high, mass is very low; surface effects are important
*
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Electrostatic (ES)Electrostatic (ES)
Charged
Charged
Anchor point
shuttle
ES Unit
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Thermal Engines (T)Thermal Engines (T)• Expansion
Material, external; inkjet
Bimorph beam - bending
• High force, moderate displacement
• Frequency limited by conductivity
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Bimorph Beam (Thermal)
Bimorph Beam (Thermal)
Resistive heater
off
onLow CTE
High CTE
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ElectromagneticElectromagnetic
U of WisconsinCalTech
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MEMS PumpsMEMS Pumps• Actuation Mechanisms
Electrostatic Thermal Magnetic Pneumatic Piezoelectric Ultrasonic
• Direct Fluidic Actuation Fluidic phase change Electrohydrodynamic (EOF, electrophoresis, etc) Direct fluidic actuation mechanisms
Debiotech STMicroelectronics insulin pump
Bellows: Air Pump
Thermal Inkjet
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Sensors – the #1 ClassSensors – the #1 Class
• Capacitance
• Piezoresistive
• Resonant beam
• Electron tunneling
• Photonic
• Chemical
• Biological/biochemical
Popular forAccelerometers, mics, more
Popular forAccelerometers, mics, more
Manyprinciples
Manyprinciples
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Inertial Sensors (motion)
Inertial Sensors (motion)
• Accelerometers Capacitor
Resonant
Multiple axis
• Gyroscopes
ADI
ADIJPL
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Accelerometer/GyrosAccelerometer/Gyros• Automotive
Sensing: crash, torque, vibration (well-being) Navigation; GPS back-up Active suspension
• Consumer Input device; computer, games, phones Sports training, medical therapeutic Alarms; burglar, seismic (earthquake) Stabilization, camera
• Military Ordnance; guidance, condition, attack warning Operator input/control Aiming; gun, camera (stabilization)
• Industrial Sensing: vibration, tilt, direction, rate Stabilization Monitoring Robotics; position, contact, feedback, etc.
ADI
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Now owned by ADI
3-Axis Accelerometer
Z-Axis Gyroscope
Dual-Axis Gyroscope
ResonantAccelerometers
INERTIALINERTIAL
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Accelerometer Applications
Accelerometer Applications
• ABS/Antiskid
• Airbag Deployment
• Anti-Rollover Detection
• Battery Disconnect
• Crash Alerting
• Dynamic Suspension
• Dynamic Ride Control
• Dynamic Cruise Control
• Electronic Park Brake
• Fleet Monitoring
• Fuel Shutoff
• Headlight Leveling
• Inertial Navigation – backup
• Misfire Detection
• Security/Antitheft
• Seatbelt Tensioning
• Stability Systems
• Tilt Sensing
• Tire Motion
• Tire Pressure
• Transmission
• Monitor Vehicle Performance
• Active Subwoofers• Ambulatory Training • Appliances • Binoculars• Blood Pressure Monitor • Camcorders Stabilizer• Digital Pens • Digital Cameras Stabilizer• Disk Drive Monitoring • Game Controllers Handheld GPS • Head Tracking Inertial Navigation • Laptop Anti-Theft • Laptop Drop Detection • Joysticks Mouse - 3D• Out-of-Balance Medical Devices • Sleep Monitor Pedometers • Sports Training – golf• Sports Training – fly cast• Sports Training – batting• Tilt Sensing • Virtual Reality I/O• Wearable Computing I/O
• Antenna Alignment
• Antenna Switches
• Construction Leveling
• Machine
• Health Equipment
• Tilt Sensing
• Fork Lift Positioning
• Marine Navigation
• Platform Leveling
• Seat Damping
• Seismic
• Gas Shutoff
• Satellite Dish Alignment
• Satellite Gyroscopes
• Ship mechanical monitoring
• Shock Sensing
• UAVs
• UMVs
• Vibration Monitoring
Industrial/Scientific/Military Automotive Consumer
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Fuel Pressure Sensor
Injector Pressure Sensor
• Pressure Sensors Fuel Tire Manifold Injector AC Mass air Break Fuel vapor Oil
AC Pressure Sensor
AutomotivePressure Sensors
AutomotivePressure Sensors
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Pressure SensorsPressure Sensors
• Transducers Piezoresistor Capacitor Resonant beam
Internal ref. pressure
Thin diaphragm
Transducer
Resonating beam (F1) Resonating beam is now under tension; (F2)
Vacuum
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Chemical SensorsChemical Sensors
Readily detects H2, CO, Alcohols, Hydrocarbons
Reactive surface adsorbs gases
i
Heater
Chem-sensor gate; adsorbing metal like Pd
Adsorption lowers threshold voltage since a dipole is induced.
Chem-FET
Vs Vd
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Mechanical TransferMechanical Transfer• Gears
• Wheels
• Levers
• Rackets
• Shuttles; walking beams
• Hinge & lock
• Articulated beams
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Power Device ClassesPower Device Classes
1. Extractors using ambient energy
2. Converters: energy-1 energy-2
3. Relays for power (not signal)
4. Power controllers (beyond relays)
5. Generators using fuel
1. Uses waste energy, 2. Uses generated energy
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Power ExtractorsPower ExtractorsTypically utilize machine mechanical vibrations
C1
C2
Changing capacitor plate spacing generates power; reverse damper.
Machines produce mostly 1 KHz to 5 KHz vibrations
C2 an be replaced with a magnet.
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Power MEMSPower MEMS• Chemical fuel to:
Mechanical rotation, reciprocation, etc.
Fluid or gas pumping force
Electrical (fuel cell)
Thrust; rocket
Mechanical Electrical (turbo-generator)
• Photonic to electrical (really just a converter)
• Mechanical, electrical to chemical (battery)
10 to 100 watts 100 K to 1-million RPM
10 to 100 watts 100 K to 1-million RPM
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Gas TurbineGas Turbine
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TI MOEMS: DLPTI MOEMS: DLPon off
Ref. “Digital Light Processing TM for High-Brightness, High-Resolution Applications” Larry J. Hornbeck, Ti.com
on
on
on
on
on
off
Over 8-million partsOver 8-million parts
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TexasInstrumentsDLPTM
1,400,000 mirrors in one module
1,400,000 mirrors in one module
animation by kbganimation by kbg
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Session SummarySession Summary
• Most MEMS are directly electrically powered
• Electrostatic is simplest; very popular
• Bimorph is ideal for no/low wear beams
• Many kinds of mechanical transfer
• Sensors will remain largest market
• Reliability issues on some, but not all MEMS