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Vibration
- 1. IN THE NAME OF GOD AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 2. AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 VIBRATION SECTION-14 DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 3. AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE F22 fighter
- 4. INTRUDUCTION Definition:Motion repeatedly alternates in direction AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 Examples:Tides & Ocean waves-Earthquakes-Pistons-Turbulent air-Travelling uneven terrain-Helicopters-Low level flight(fixed-wing)-High speed sea-craft Transmission:Direct contact-Air-Water-Soil conduction Significance:Impair visual acuity-Lead to fatigue-Interfere with neuromascular control&speech- DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 5. INTRUDUCTION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 6. PRINCIPLES OF VIBRATION 1-Natural vibration AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 -Mass hanging by a spring(Normal mass spring system) -Repeated interchange of energy(mass: Gravitational& spring:In Extention) -Air resistance for mass & Heat production for spring -Sinusoidal graph:Mass Frequency(C/S-Hz)&Spring Amplitude(Meter) -Damping:Spring heat production-Damper:Piston in an oil-filled cylinder Forced Vibration) DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 7. PRINCIPLES OF VIBRATION 1-Natural vibration Representation of the Measures of Vibration Exposure DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 8. PRINCIPLES OF VIBRATION 2- Forced vibration Mass spring damper system DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 9. MECANICAL PROPERTIES OF BIOLOGICAL TISSUES -Spring:Springiness-Uniform stiffness-Non biological effect AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 Tendon& Muscle:Elasticity_Non-uniform stiffness-Biological effect (Muscle tension & contraction) DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 10. VIBRATION SOURCES 1- Engine 3600rpm(60Hz) 2-Environment:Land travelling-Flying-Sailing DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 11. VIBRATION SOURCES -Low frequency& High amplitude vibration(number of rotor blades&speed-<100Hz) -Three axes motion(vertical-lateral-backward&forward) DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 12. VIBRATION SOURCES Comparison -Propeller-driven aircraft 6000 rpm-100Hz -Fixed-wing jet aircraft:8000 rpm-130Hz -High-pressure(Dual –stage)turbine:13000rpm-230Hz DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 13. VIBRATION SOURCES:Remarkable 1-Atmospheric turbulence 2-Storm-cloud penetration 3-High-speed low level flight DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 14. VIBRATION SOURCES Modified 1-Pilot control 2-aerodynamic charactristics DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 15. MEASURMENT AND ANALYSIS OF VIBRATION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 -Accelerometer: High acceleration impact or below the threshold of human perception DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 16. MEASURMENT AND ANALYSIS OF VIBRATION DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 17. MEASURMENT AND ANALYSIS OF VIBRATION Vibration wave form: 1-Periodic wave:Machinery 2- aperiodic wave:Atmospheric turbulence 3-Vibration spectrum:Amplitude–frequance plot DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 18. BIOMECANICAL EFFECTS OF VIBRATION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 1-Mecanical impedance of the body 2-Body resonances DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 19. BIOMECANICAL EFFECTS OF VIBRATION 1-Mecanical impedance of the body AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 Definition:Force-Vibration Response(Peak oscillatory force/Peak velocity of vibration) DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 20. BIOMECANICAL EFFECTS OF VIBRATION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 Body resonances DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 21. Body resonances Effects: 4-5Hz:Shoulder vibration 5-8Hz:Difficulty in controlling tasks 14-15Hz:Head vibration 15-20Hz:Facial tissues vibration 20-40Hz:Visual Acuity impairment DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 22. EFFECTS OF VIBRATION ON VISION 1- Focus in image formation AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 2- Directed on the fovea without motion (Vestibulo-ocular-R+Pursuit-R) 3-VOR Decreased:Angular velocity >40 degrees/S(outside inviornment) 4- Pursuit-R Decreased:Oscillation>1Hz/S(pilot&instruments>1-2Hz/S) 5-Other factors :Size-Line width-Colour-Brightness-Contrast DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 23. EFFECTS OF VIBRATION ON VISION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 24. EFFECTS OF VIBRATION ON VISION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 (HMDS) made by Vision Systems International, LLC (VSI) recently flew for the first time on an F-35 Joint Strike Fighter aircraft. The HMDS provides the pilot video with imagery in day or night conditions combined with precision symbology to give the pilot situational awareness and tactical capability. The HMDS has been in development for five years and recently completed all required safety of flight tests toward full certification. Helmet-Mounted Display Systems DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 25. EFFECTS OF VIBRATION ON VISION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 26. CARDIOVASCULAR EFFECTS OF VIBRATION 1-An increase in PR at the start of vibration 2-An increase in BP 1-2h afterward vibration 3-Pripheral vasoconstriction 4-Transient arrhythmia 5- Fatal dysrhythmias DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 27. RESPIRATORY EFFECTS OF VIBRATION 1-An increase in RR 2-Oscillatory airflow in 3-4Hz-Gz vibration(effects on gas exchange) 3-Hyperventilation&Hypocapnia DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 28. RESPIRATORY EFFECTS OF VIBRATION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 29. NEUROMASCULAR EFFECTS OF VIBRATION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 1- Reflex contraction(20-100Hz-in directly vibration) 2- Reflex inhibition(in whole body vibration) 3-Neck muscle vibration :Illusion of forward flexion 4- Rectus abdominis vibration :Illusion of extension of the upper trunk 5-Stop vibration :Transient illusion of motion in the opposite direction DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 30. VIBRATION AND MOTION SICKNESS -Whole body vibration:0.2-0.7Hz in seated -Prevention:Supine posture DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 subjects(Gx>Gz)
- 31. INFRASONIC VIBRATION -F<25Hz(if High intensity) -Feeling of ear fullness or pressure-nausea-imbalance-Chest tightness-Tiredness- Vascular injection-Vertical nystagmus-low concentration -Psychological stressor effects DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 32. HUMAN TOLERANCE TO VIBRATION -15 well-motivated volunteers -Tolerance:4-8 Hz vibration -Main symptoms :Precordial & central abdominal pain -Difficulty in breathing:1-3 Hz -Nodal tachycardia DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 33. HUMAN TOLERANCE TO VIBRATION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 34. PROTECTION AGAINST VIBRATION AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 1- Attention to the source of vibration(engine design) 2-Modification of the transmission pathway(dynamic vibration absorbersConnecting the seat-pan and backrest to the body - seat-Active vibration absorption ) 3- Alteration of the dynamic properties of the body DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 35. OCCUPATIONAL HAZARDS OF VIBRATION AVIATION MEDICIN SERIES -VIBRATION WHITE FINGER: ERNSTING S AVIATION MEDICIN -Hand-held vibrating tools FOURTH EDITION-2006 -20-200Hz-after months or years VIBRATION-SECTION14 -Tingling or numbness in the finger-Attacks of finger blanching(cold)-Touch & temprethre sensation impaired-Dusky cyanosis-Finger pulps atrophy(skin necrosis) DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE
- 36. OCCUPATIONAL HAZARDS OF VIBRATION -WHOLE-BODY VIBRATION -4Hz(vertical-fore-aft-rotational) -Disorders of the lumbar spine-stomach-related disorders -Drivers of tractors-earth-moving vehicles and trucks DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14
- 37. AVIATION MEDICIN SERIES ERNSTING S AVIATION MEDICIN FOURTH EDITION-2006 VIBRATION-SECTION14 DR.EBADI.A –FACULTY OF AEROSPACE & DIVING MEDICIN ARMY UNIVERSITY OF MEDICAL SCIENCE F35 fighter