1 / 22

Andreas Schrempf, Thomas Minarik Upper Austria University of Applied Sciences Medical Engineering

Andreas Schrempf, Thomas Minarik Upper Austria University of Applied Sciences Medical Engineering Linz, Austria andreas.schrempf@fh-linz.at. An interactive activity- monitoring device for use in home- rehabilitation . Upper Austria University of Applied Sciences.

yves
Download Presentation

Andreas Schrempf, Thomas Minarik Upper Austria University of Applied Sciences Medical Engineering

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Andreas Schrempf, Thomas Minarik Upper Austria University of Applied Sciences Medical Engineering Linz, Austria andreas.schrempf@fh-linz.at An interactive activity- monitoring device for use in home- rehabilitation

  2. Upper Austria University of Applied Sciences 4th International Conference MRH | Pilsen June 30th 2011

  3. Upper Austria University of Applied Sciences 4th International Conference MRH | Pilsen June 30th 2011

  4. Faculty of Applied Health and Social Sciences Campus Linz ... Education: Applied Health and Social Sciences Research: - Medical Engineering - Assisting Technologies and Processes for the Elderly Rehab. Amb. Linz Hospital Diakonissen GKK-OOE Health Ins. Comp. Emergency Hospital Linz General Hospital Linz University of Applied Sciences Campus Linz Pediadric and Gynecological Clinic Linz Most of the medical partners are within a square km. Neurological Clinic Wagner Jauregg Linz 4th International Conference MRH | Pilsen June 30th 2011

  5. Activity Measurement Application Areas Application and Benefits : • preventive care • measures taken to prevent diseases • motivation factor • therapy evaluation • objective measures of the therapy progress • Documentation • assessment • therapy control • compare exercise measurement data against golden reference • adjust intensity according progress, • provide feedback 4th International Conference MRH | Pilsen June 30th 2011

  6. Device DevelopmentActilab – Features • developed in cooperation with g.tec medical engineering • Device development – g.tec medical engineering • Algorithm development – FH-OOE • Mobile system • duration, intensity, frequency of activity • Intended to become a medical device • Triaxial accelerometer • measuring range: ±18g • Resolution: ~ 6.25mg • Barometric pressure sensor • Measurement range 30-120kPa • Resolution: ~10cm • GSM module 4th International Conference MRH | Pilsen June 30th 2011

  7. Device DevelopmentNEON – Features • developed in cooperation with spantec GmbH • Triaxial accelerometer • measuring range: ±8g • Resolution: ~ 3.9mg • Barometric pressure sensor • 30 kPa - 120 kPa measuring range • Resolution: 1.5 Pa ( ∼ 10cm at s.l.) • GPS module • accuracy position: 5m CEP (Circular error probable) • accuracy velocity: 0.1m/s • update rate: 1Hz 4th International Conference MRH | Pilsen June 30th 2011

  8. Device DevelopmentNEON – Features ANT module mini USB connector LEDs 4th International Conference MRH | Pilsen June 30th 2011

  9. Device DevelopmentNEON – Features • Compatible with all ANT(+) devices • e.g. Garmin HRM1G • micro SD-card • 2 GB data memory • UART connection to local PC • ANT module • 2.4GHz wireless networking protocol designed for wireless sensor networks • network (internet) connection possible (bridging) 4th International Conference MRH | Pilsen June 30th 2011

  10. Device DevelopmentCommunication Concepts Actilab NEON 4th International Conference MRH | Pilsen June 30th 2011

  11. AccelerometryCOM moves during Walking Center Of Mass (COM) moves during walking according to the different phases of the walking cycle 4th International Conference MRH | Pilsen June 30th 2011

  12. AccelerometryCOM moves during Walking Frequency and amplitudes change depending on walking speed 4th International Conference MRH | Pilsen June 30th 2011

  13. AccelerometryCOM moves during Walking vertical acceleration: Putting an activity measurement device near to the COM allows to measure these movements in terms of the accelerations. 4th International Conference MRH | Pilsen June 30th 2011

  14. AccelerometryPA -Energy Expenditure Physical activity level (according to WHO) (1.2 sitting, 1.8-1.9 walking) Total Energy Expenditure (TEE) TEE = BMR + DIT + PA • BMR: basal metabolic rate BMR • DIT: diet induced thermogenesis • PA: physical activity 4th International Conference MRH | Pilsen June 30th 2011

  15. AccelerometryPA - Energy Expenditure Estimation ( modified Goldman equation) • T: terrain factor • : overall efficiency • m: body mass • v: walking speed • a(v): total average acceleration, depends on walking speed • dh/dt: change of elevation per time unit • g: gravity constant 4th International Conference MRH | Pilsen June 30th 2011

  16. AccelerometryPA - Energy Expenditure • overall efficiency, depends on age, fitness level, gender, … • estimation based on mean acceleration (indoor/outdoor) • measured by GPS (outdoor) • measured by acceleration sensors • measured by barometric pressure sensor (indoor/outdoor) • measured by GPS (outdoor) 4th International Conference MRH | Pilsen June 30th 2011

  17. AccelerometryPA - Energy Expenditure running a(t) LP | . | HP walking mean total body acceleration • High-pass filtering (offset, artefacts) • rectifying (power) • Low-pass filtering (mean acceleration) • distinguishing between no activity, walking and running • estimation of walking speed 4th International Conference MRH | Pilsen June 30th 2011

  18. AccelerometryPA - Energy Expenditure running walking Estimation of walking speed (based only on accelerations) 4th International Conference MRH | Pilsen June 30th 2011

  19. AccelerometryPA - Energy Expenditure dE/dt [kcal/min/kg] HR [bpm] heart-rate measurements allows to estimate the EE: • depends on age, • depends on fitness level, • depends on gender, • different for walking and running, • hysteresis, • direct measurement of the energy expenditure (allows to quantify the efficiency) 4th International Conference MRH | Pilsen June 30th 2011

  20. AccelerometryAccuracy Assessment forest (low GPS signal quality) altitude: GPS vs. pressure sensor • pressure sensor requires stable weather conditions, • GPS accuracy limited, when low signal quality • GPS may loose signal, does not work indoor 4th International Conference MRH | Pilsen June 30th 2011

  21. AccelerometryAccuracy Assessment altitude GPS (low signal quality) stairs up, then down altitude barometer round trip walking speed prediction by accelerometer (problem: up and down) stairs down walking speed GPS walking speed: GPS vs. barometric press. sensor • pressure sensor requires stable weather conditions, • GPS may loose signal, does not work indoor • --> sensor fusion 4th International Conference MRH | Pilsen June 30th 2011

  22. AccelerometrySensorfusion/Autom. Calibration Solutions: • Sensor fusion combining GPS and barometric pressure sensor. Weighting of signal depends on signal quality and/or availability • Individual calibration of speed prediction algorithm, during good GPS-signal quality • Individual calibration of efficiency using heart-rate monitor Problems: GPS signal only available outdoor GPS: altitude low accuracy, especially for small altitude differences barometric height measurement only valid for short time or during stable weather conditions Speed prediction by accelerometer not accurate enough when going up or down Efficiency not constant varies between different subjects (depending on age, fitness level or pathology)V 4th International Conference MRH | Pilsen June 30th 2011

More Related