Maciej Kalarus

IMU –Inertial Measurement Unit(gyro + accelerometer)

• provides angular rate/linear acceleration• do not provide navigation solution!

INS – Inertial Navigation System(set of 3-axial gyros and accelerometers + integration algorithm)

• provides navigation solution (3-dimentional solution – linear, angular parameters)

INS and IMU are commonly used as synonyms

TerminologyTerminology

Integration modes• uncoupled mode• loose integration, open loop• tight integration, closed loop• ultra-tight integration

The Northrop Grumman Navigation Systems Division (NSD) LN-260 is a Form, Fit, and Function replacement INS/GPS for the F-16.

ApplicationsApplications

Personal navigation Personal navigation –– system architecturesystem architecture

Knowledge-Based System (KBS)

Human locomotion model

DeadRockoning (DR)

Algorithms

Data Collection

Sensor Calibration

Auxiliary data(image/map)

step length (SL)headingaltitude

navigation solution

navigation solution (EKF)

GPSINS

BarometerCompass

Step sensors

Personal navigationPersonal navigation

Independent modelling od Step Length (SL) using Artificial Neural Networks (ANN)and Fuzzy Logic (FL)+ heading determined by gyro - INS HG1700

Indoor navigationIndoor navigation

Indoor navigation Indoor navigation –– summarysummary

Long term accuracy of dead reckoning inside the buildings requires additional information e. g. digital pictures /maps.

3-Axis Rate Gyro 3-Axis Accelerometer 3-Axis Magnetometer

Mobile GPS LaboratoryMobile GPS Laboratory

Power RequirementsInput Voltage 10 VDC - 32 VDCPower 1.2W maxMeasurementsAngular rateRange ±300 °/secNon-Linearity 0.1% of FSNoise Density 0.05 °/sec/Hz0.53dB Bandwidth 20 HzAccelerationRange ±6 gNon-Linearity 0.3% of FSNoise Density 150 mg/Hz0.53dB Bandwidth 20 HzAttitude Accuracy (Tilt) 0.4° (1 s)Position Accuracy 2m CEP, WAAS/EGNOS availableData Output RatesPosition , Velocity, attitude, rates, accelerations 50 HzRaw GPS measurements 5 Hz (WAAS/EGNOS)PhysicalSize 1.50” W x .87” H x 1.67” DWeight 55 grams

MEMSMEMS

Micro-Electro-Mechanical Systems (MEMS)Built using silicon micro-machining techniquesUses Coriolis effect using vibrating elements

Fc -Force m -mass w -angular velocity v –velocity

AdvantagesSmall size, low weight, low power, inexpensive to produce

DisadvantagesMEMS less accurate than fiber-optic based or ring laser gyrosComplex algorithms needed to generate solutionsLoses accuracy quickly due to bias drift characteristics

MEMSMEMS

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INS mode

VG mode

Mobile GPS Laboratory Mobile GPS Laboratory –– ttest resultsest results

INS solution valid for about 20 seconds during GPS outagesINS + GPS did not significantly improve accuracy using the MIDG-INSData during GPS outage followed theoretical trend

ConclusionsConclusions

• use MEMS to improve GPS measurements • develop a testing platform to measure static/dynamic parameters of the IMU• use additional sensors to improve navigation solution during GPS outages• develop INS-GPS for people and mobile robots

Our plansOur plans

czy może- to use….- to develop…???