HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

HASTACHigh stability Altimeter

SysTem for Air data Computers

André LarsenR&D Director

Memscap Sensor Solution

SIXTH FRAMEWORK PROGRAMMEPRIORITY 4

Aeronautics and Space

EC contract no. AST4-CT-2005-012334

www.hastac.biz

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

HASTAC project outcomeHASTAC will develop:

A uniqe MEMS basedsensor with excellentlong term stabilityA hermetic sensor package optimised for aerospace applicationsAn optimised altimeter pressure transducerA new digital ADUDemonstration of theperformance in a rotary wing test fligth

Technology for a better society

Project factsTotal cost: 2.895.000 €Funding: 1.500.000 €Duration: 35 monthsStart date: 11 Jan 2005

Project webwww.hastac.biz

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

Strategic objective To increase the safety in all in-flight situations, particularly low visibility situations, by improving the transducers used in Air Data Computers for aircraft applications.

Improved aircraft performance1. Auto pilot situations in the reduced vertical separation

minima legislation of 1000ft (RVSM)2. Demanding manual flying situations in darkness and low

visibility3. Increased reliability in altitude information for manual and

automated Air Traffic Control systems used in transponder applications

4. Aircraft Traffic Collision Avoidance Systems will also benefit from more accurate and reliable altitude information

Why

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

Sensor element•Long term drift factors•Modelling, simulation & design•Process development•Fabrication & prototypes•Test & characterisation

Sensor package•Theoretical study•Design & pilot production•Assembly of pilot batch•Test & qualifications

Transducer•Concept & feasibility•Design of prototypes•Development & optimisation•Industrial prototypes•Test & certification

Air Data Computer•Technical specifications•Design of hardware & software•Pilot batch manufacturing•Performance test•Safety of flight qualification

Aircraft flight test•Flight test program•Helicopter installation•Ground testing•Safety of flight qualification•Test flight•Data analysis

Project consortium

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

WP3 TP4000This Work Package aim to make a high end transducer for

the new SP83 sensor

High accuracy and stability better than 0.01%fs/year

The program includes optimization of:Excitation methodNoise to signal ratioCalibration processCalibration method and technique

Activities:DO-254 proceduresQualification and testing

Deliverables :Engineering prototype to WP4Industrial prototype to WP4

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

TP2000Units

Low cost version of TP4000:Single ADCSP82Faster calibrationEasier compensation

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

TP4000Input to design

Increased focus on safety and reliability

Dual ADC based on experience with TP2000 and FTA

Evaluate methods for calibration

Large storage capacity to achieve higher accuracy in compensation method

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

TP4000Usage of TP2000 experience

TP4000

TP2000

SPI

Power

Temperature

Pressure Sensor

Excitation

AD7793

EEPROM

Reference, regulator, filter, protection

External system

AD7794 Pressure

Temperature

PB

PB PB TB

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

TP4000Difference from TP2000

Additional built in test during power-up:Verify AD7793 by using AD7794Use AD7793 to verify AD7794Verify drift in pressure bridge versus temperature bridgeVerify sensor excitation

In addition:More than double sample rate versus TP2000Possibility for synchronised pressure and temperature conversionLoss of function probability (MTBF) only ~5% worse than TP2000Misleading information probability (FTA) ~100% better than TP2000

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

CalibrationHow it worksProcedure:

Apply pressures and temperaturesCollect ADC dataCurve fit to referenceWrite constants to unit and verify

Temperature (left) and pressure (right) versus time for calibration and verification

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

Curve fit methodsData from a representative TP2000 (110767)

260 curve fit methods were compared

High order Chebyshevpolynomials have most potential

Chebyshev FTaylor FTaylor FFourier PChebyshev PChebyshev PChebyshev PChebyshev PType

-0.08800.0575H-0.06970.0327G-0.05720.0295F-0.02510.0151E-0.00380.0142D-0.00350.0142C-0.00400.0047B-0.00360.0039AMinMaxID

Deviation (%FS)Equation

P=polynomialF=function

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

TP4000Calibration procedure

T ADC80 points

P ADC25 points

Chebyshev curve fit

Bilinearinterpolation matrixgeneration

Measured data:• T ADC• P ADC• P Ref xx coefficients

Write to TP4000(8.2kB)

Improved curve fit and constants:

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

Matrix size vs max deviation

TP2000 110767

TxP=80x25

→ D<0.005%

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

TP4000Safety featuresThese features ensure safe operation of the TP4000:

Voltage regulator with high, low and reverse polarity protectionRegulator low power supply voltage detectionHardware lock input for write protection of EEPROMESD protection devices

These features can be implemented in external system for safety:Error detection on EEPROM communication by CRCError detection on ADC communication by multiple readRange checks on ADCs and calculated outputs (pressure, temperature)Communication timeout for loss of function detectionVerify ADCs against each otherVerify sensor excitationVerify drift of sensor bridge (temperature)

New from TP2000 to TP4000

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

TP4000Target Specification

Parameter Min / Typical Max Unit Power-supply 6.5* 20 V Current consumption 5* mA Pressure range (absolute) 50 1150 mBar Overpressure 200 % FSO Total pressure error (absolute) ±0.02** % FSO Long term stability (at ambient temperature) ±0.01** % FSO / year Pressure resolution <0.00005* % FSO Output noise ±0.001* % FSO Conversion time 25* ms Response time 50* ms Total temperature error < ±1* °C Temperature resolution <0.0002* °C Calibration temperature range -40 80 (105***) °C Operating temperature range -40 105* °C

* Estimate based on experience from other pressure transducers.** Estimate based on expected effect of improved calibration procedure and new SP83.*** Larger temperature range possible. This can influence the accuracy.

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

New generation of silicon MEMS barometric pressure sensors and fully compensated and digitized Transducers (TP4000)

Sensor systems with significantly improved altitude accuracy capabilities over time, target is better than 100ppm/year (0.01%/year)

Aircraft flight testing will demonstrate the effectiveness of the improvement

The new generation of transducers with a new silicon micro sensor (absolute pressure sensing element) as the key component, will also be available for other application areas, such as transponders and cabin pressure control systems.

How

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

WP 1 Sensing elementMiNaLab facility

Clean room area:SINTEF: 800 m2

University of Oslo: 600 m2

A full silicon processing line for MEMS and radiation detectorsCapacity of 10.000 6”wafers/year Located at the campus of University of Oslo240 MNOK investeted in scientific equipment and laboratory infrastructure

Technology for a better society

WP 1 Sensing elementLong term drift factorsModelling, simulation & designProcess developmentFabrication & prototypesTest & characterisation

HASTAC is carried out with financial support from the European Community FP6 Research Area 4 – Aeronautics & Space

ADU and Flight testNext generation air data unit development

Primarily to integrate HASTAC transducerElectronic interfaceSoftware interface

Optimise design of interfacesEvaluate performance in lab simulated environment over extended time period

Flight testExpose ADU and transducers to representative real life environmentSevere vibration environment experienced on helicoptersHigh hours utilisation on emergency services helicopterMonitor transducer performance during evaluation period and beyond