- 1. An Ultra-Thin Sensor for Measuring Contact
StressLLNL-PRES-637035This work was performed under the auspices of
theU.S. Department of Energy by Lawrence LivermoreNational
Laboratory under contract DE-AC52-07NA27344.Lawrence Livermore
National Security, LLCJack Kotovsky, Ph.D.
2. Automotive Brake Pads Gaskets Impact Studies In-situ Tire
Monitoring Medical Cartilage Mechanics Podiatry Bedding/Prosthetics
(Pressure Sores) Clinical Tumor Monitoring Industrial Composite
Layups/Lamination Molding Presses Gaskets and Bolted Joints Roller
Systems RoboticsAuthor-9/12/2014-2Lawrence Livermore National
Laboratory LLNL-PRES-637035 3. Commercial Sensors Are
InadequateFunctions Needed: Fuji Pressensor Film Tekscan Sensor
LLNL MEMS SensorRepeated Measurements NoAuthor-9/12/2014-3Lawrence
Livermore National Laboratory LLNL-PRES-637035Yes(~100 load
cycles)YesDynamic Measurements NoYes(~100 load cycles,
limitedbandwidth)Yes, bandwidth ~200kHzAccuracy 10%+/- 3%
(immediatelyfollowing calibration)+/- 3%Hysteresis N.A. 4.5%
2%Minimum Thickness (limitsaccuracy in application)220 m (0.009)
200 m (0.008) 100 m (0.004) 4. The sensor measures contact stress
(squeezing force) between twosurfaces The measurement is: Accurate
Repeatable for long-term (embedded) use Static or dynamic (200
kHz+) This technology was developed to address a measurement gap
Measures real-time interface loads accurately andreproducibly
Measures dynamic interface loads Can be embedded in a product
Withstands harsh environments (-40 C to 70 C, severevibration,
persistent use)Lawrence Livermore National Laboratory
LLNL-PRES-6370354MEMS SensorBond PadDiaphragmDopant Implant
(Piezoresistors)Contact Windows MetallizationDiaphragm Etch Street
Etch 5. This technology conquers a barrier in silicon fabrication
andpackaging LLNL IP: thin MEMS design and paper-thin packaging The
device is similar to successful pressure sensors but is paperthin A
full Wheatstone bridge provides thermal compensation Sensor
measures temperature and/or stress Piezoresistive single-crystal
silicon (large signal) Silicon is perfectly elastic No calibration
loss High bandwidth Load sensitivity tuned by diaphragm
dimensioningLawrence Livermore National Laboratory
LLNL-PRES-637035LLNL Sensor Demonstrates Excellent5Load Performance
6. 900 Independent silicon device islands on860 m
centers220mLawrence Livermore National Laboratory LLNL-PRES-637035
6 7. Application Description Target Customers Current Practice#1
Real-time, Embedded, Nip Roller pinch control Roller-system
manufacturers manual adjustment of pinch =Lawrence Livermore
National Laboratory LLNL-PRES-637035production pauses#2 Robotic
manipulator grip force control Robotics companies Total force
measurement misseslocal interface pressure#3 Automotive tire
molding: Real-time pressure adjustment Tire manufacturers Models
and empirical data#4 Cartilage load sensing for orthopedic implants
and procedures Orthopedic companies Laboratory sensors only#5
Embedded shoe sensor for wear detection and injurypreventionShoe
companies No sensor for embedded shoemonitoring#6 Hospital bed
monitoring for the prevention of bed sores Medical device companies
No sensor for embedded product use#7 Gasket/seal stress sensing
Industrial and Automotive No sensor for real-time interfaceload
measurement#8 Bullet Proof vest/helmet design for the prevention of
blastinjury or impact loading in sportsMilitary and civilian helmet
andarmor manufacturersNo dynamic interface load sensorexists7 8.
The technology is available for commercialization and is production
ready The sensor is in production within the Department of Energy
and continuesto find new internal applications and customers Sensor
critical to LLNL programmatic needs >10 year investment No
research is necessary to bring the single sensor to marketLawrence
Livermore National Laboratory LLNL-PRES-6370358Wmpoweruser.com 9.
Charity [email protected] Livermore National
Laboratory LLNL-PRES-637035 9