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Microflown TechnologiesThe Netherlands

www.microflown.cominfo@microflown.com

Microflown: a new category of sensors

Introduction

Company Introduction1994: Invention Microflown by Hans-Elias de Bree at University Twente

1997: Ph.D. Hans-Elias de Bree

1998: Founding Microflown Technologies B.V. (de Bree, Koers)

2001: Industrializing product

2003: Introduction broad banded sensor element

2004: First applications scientifically proven / first arrays sold

2005: Rapid growth in (automotive + aerospace) industry

2005: De Bree appointed Professor ‘Vehicle Acoustics’ at the HAN University, Arnhem School of Automotive Engineering

2008: Strategic decision to explore the defense & security market

2010: 20 FTE company, 2 MEURO turnover

Company Introduction• Main markets Microflown is focusing on are Automotive, Aerospace and

Defense• 2 million euro turnover• Rapidly growing company• Own faculty at the Han University of Automotive engineering in Arnhem• Within total of 20 FTE employed, we count:

• Two professors• Two more PhD• Two academic engineers• Eight engineers a higher vocational level• Five EU nationalities (Dutch, German, Italian,Scottish, Spanish)

ReferencesAutomotive - OEMAudi, BMW, DAF Paccar, Daimler, Ford, Freightliner, Harley Davidson, Honda, Isuzu, Mazda, Nissan, PSA Group ( Peugeot - Citroën ), Renault Samsung, TATA, Toyota, VolkswagenAutomotive - OthersAISIN, Behr Group, Eaton USA, Faurecia, Fontijne Grotnes, Harman Becker Automotive Systems, ISM Automotive, Jatco, Mirror Controls International, Mitsuba, Rieter Automotive, Rietschle Thomas, Robert Bosch, Siemens VDO, StankiewiczAerospaceAirbus France, Airbus Germany, DLR ( German Aerospace Center ), General Electric Propulsion Systems, Progency Systems Corporation

ReferencesDefense & SecurityAeronautical Development Establishment Bangalore, Batelle, BBN, Dutch Ministery of Defense, University of the Federal Armed Forces ( Germany), Naval Post Graduate School, Wehr Technische DienstTest housesLMS International, Mueller-BBM, Ricardo UK, SPEKTRAOther IndustriesASML, BOSE, CAE Engineering and Services, Canon, CNAM, EMPA, Fisher-Rosemount, INRS, INSA, KAZ, KNMI, Kobe Seitetsusyo, MSX International, Nippo Hoso Kyokai, Oticon, Pioneer, RION, Sick Maihak, Sony

Microflowns

Working principleMicrophone measures sound pressure (result)

Microflown measures Particle Velocity (cause)

Acoustical <-> electrical <-> energySound pressure <-> voltage <-> potentialParticle velocity <-> amperes <-> kinetic

Working principle

PRESSURE WAVEPRESSURE WAVE

Working principle

PRESSURE WAVE PRESSURE WAVE ≠ ≠ PARTICLE VELOCITYPARTICLE VELOCITY

Working principle

Microflown SEM picture: two heated wires

Working principle

ou tpu t

T[k

]velocity

d is tance 0

u pstream d ow n stream

Working principle

Working principleSurface velocity measurement:• No background noise and reflection problems

Figure of eight High surface velocity and low surface pressure

Low surface velocity and high surface pressure

Working principle

Mems based sensorClean room technology is used to create the small elements on a waver

University of Twente

Working principle

Wirebonded elements

Standard probes

Scanning Probes• 1D Velocity• For small object• High temperatures• Non contact vibration

Standard probesPU probes• Particle Velocity• Sound Pressure• 1D Sound Intensity• 1D Sound Energy• Impedance

Standard probes

PU Probes: Placement of p and u

Standard probesMetal Mesh• Wind shield, DC

flow up to 2 m/s• Protecion of the

wires• Calibration

including mesh

Standard probes Array applications: From product development till end of line control

Standard probesUSP probes• 3D Particle Velocity• Sound Pressure• 3D Sound Intensity• 3D Sound Energy• Impedance• Acoustic Vector Sensor

Standard probes

3D Sound Chip

Standard probesApplication examples• Hostile fire localization• Air to ground applications (PGM, UAV’s, etc.)• Border control (passive, unattended ground sensor node)• Passive surveillance (also in urban environment)• Environmental monitoring• Etc.

Standard probes

Standard signal conditioner

Standard probes

Standard signal conditioner• Powering the sensor• Option for hardware correction• High or low gain setting

Standard probesHigh dB Scanning Probe• Above 135dB acoustics becomes non linear• Standard sensor overloads at 130dB• Measurement at 170dB is possible with packaged sensor

Calibration

CalibrationStanding Wave TubeLoudspeaker on one side, reference pressure microphone at the other sidein the tube, known relation between pressure at the end and pressure and velocity in the tube

Reference microphone

loudspeaker

PU probe

Standing wave <->

CalibrationPiston on a SphereKnown relation between sound pressure and particle velocity in front of the speaker.Use a reference pressure microphone to calibrate the Microflown probe.