biomechanics module

Download Biomechanics module

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  • 1. Biomechanics ModuleNewtons lawsMusculoskeletal levers and mechanical advantageClassification of force systems Vector addition and resolution

2. Biomechanics ModuleNewtons Laws Law of Inertia Law of Acceleration Law of Action-Reaction 2 3. Biomechanics ModuleLaw of Inertia (equilibrium)3 Hall, Basic Biomechanics, 5th ed 4. Biomechanics ModuleLaw of Inertia (equilibrium)4 5. Biomechanics ModuleLaw of Acceleration5 6. Biomechanics ModuleLaw of Acceleration6 7. Biomechanics ModuleLaw of Acceleration 7 8. Biomechanics ModuleLaw of AccelerationB10 pounds8 9. Biomechanics ModuleNewtons Laws Law of InertiaWithin object Law of Acceleration Law of Action-Reaction Between objects 9 10. Biomechanics Module Law of Action-Reaction For every action, there is an equal and opposite reaction (Forces occur in pairs) Between two objects10 11. Biomechanics Module Law of Action-Reaction For every action, there is an equal and opposite reaction (Forces occur in pairs) Between two objects Objects must be in contact11 12. Biomechanics Module Law of Action-Reaction For every action, there is an equal and opposite reaction12 13. Biomechanics ModuleLaw of Action-Reaction Ground reaction forceBodyGRF = weight 13 Hall, Fig 12-1 14. Biomechanics Module Musculoskeletal Levers Why is Charlie Brown up in the air?14 15. Biomechanics Module Musculoskeletal Levers Why is Charlie Brown up in the air?15 16. Biomechanics Module Musculoskeletal Levers (Force A)(MAA) vs (Force B)(MAB) Charlie Brown is up in the air if:(Charlies force)(MA) < (Linus force)(MA) Force A MAA MAB Force B fulcrum,pivot point16 17. Biomechanics Module Musculoskeletal Levers Interaction between the forces or loads on the segment and the joint Levers: two forces and a pivot point (fulcrum, axis) Internal force (muscle) External load (gravity etc) Pivot point (joint)(N.B. not consistent w/ Levangie)17 18. Biomechanics Module Musculoskeletal Levers First class lever Second class lever Third class lever Differentiated by the relative position of the internal force, external load, and pivot point18 19. Biomechanics Module Musculoskeletal Levers First class lever Internalforce fulcrum, pivot point19 20. Biomechanics Module Musculoskeletal Levers Second class leverInternal forcefulcrum, pi vot point20 21. Biomechanics Module Musculoskeletal Levers Third class leverInternal force fulcrum,pivot point21 22. Biomechanics Module Mechanical advantage 22 23. Biomechanics Module Mechanical advantage First Class Lever ExtExt IntMech Adv = 1 iffulcrum in middle fulcrum,pivot point External MA= Internal MA23 24. Biomechanics Module Mechanical advantage Second Class LeverExt IntMech Adv > 1fulcrumExternal MA < Internal MA24 25. Biomechanics Module Mechanical advantage Third Class LeverInt ExtMech Adv < 1fulcrumExternal MA>Internal MA25 26. Biomechanics ModuleClassification of force systems Linear same segment same plane same line26 27. Biomechanics ModuleClassification of force systems Linear same segment same plane same line Concurrent same segment same plane common point of application 27 28. Biomechanics ModuleClassification of force systems Linear same segment same plane same line Concurrent same segment same plane common point of application Parallel same segment same plane parallel to each other 28 29. Biomechanics Module Fun with Forces Vector addition Composition Tip to tail Parallelogram Vector resolution Graphical Trigonometric Application to human movement Parallel forces Perpendicular forces29 30. BiomechanicsVector addition Composition Works with collinear vectors Same direction (addition) + = Opposite direction (subtraction) + = 30Hall, Fig 3-11, 3-12 31. BiomechanicsVector addition Addition (composition) Works with collinear vectors 31Hall, Fig 3-11, 3-12 32. BiomechanicsVector addition Addition (composition) Works with collinear vectors 32Hall, Fig 3-11, 3-12 33. BiomechanicsVector Addition Tip to tail Concurrent vectors (vectors which can intersect) += = += =33Hall, Fig 3-13 34. BiomechanicsVector addition Addition tip to tail 34 Hall, Fig 3-13 35. BiomechanicsVector addition Addition tip to tail 35 Hall, Fig 3-13 36. BiomechanicsVector Addition Addition parallelogram + = = + = = 36 Hall, Fig 3-13 37. BiomechanicsVector addition Addition parallelogram 37 Hall, Fig 3-13 38. BiomechanicsVector addition Addition parallelogram 38 Hall, Fig 3-13 39. Biomechanics Vector Resolution Resolving a vector into perpendicular components Methods: Graph paper Trigonometry39 40. Biomechanics Vector Resolution Graphically40 Hall, Fig 3-15 41. Biomechanics Vector Resolution Graphically41 Hall, Fig 3-15 42. Biomechanics Vector Resolution Graphically42 Hall, Fig 3-15 43. BiomechanicsVector Resolution Angle Sin Cos Trigonometric0 0 130 0.500.87 3045 0.710.71oppositeadjacent55 0.820.5760 0.870.590 1 060adjacentopposite 43 Hall, Fig 3-15 44. BiomechanicsVector Resolution Angle Sin Cos Trigonometric0 0 130 0.500.87 3045 0.710.71oppositeadjacent55 0.820.5760 0.870.590 1 060 adjacentopposite 44 Hall, Fig 3-15 45. BiomechanicsVector Resolution Angle Sin Cos Trigonometric0 0 130 0.500.87 3045 0.710.71opposite 10adjacent55 0.820.57 8.760 0.870.590 1 060 adjacentopposite 5.0 45 Hall, Fig 3-15 46. BiomechanicsVector ResolutionAngle Sin Cos Trigonometric 0 0 1 30 0.500.873045 0.710.71opposite adjacent 1055 0.820.57 60 0.870.5 90 1 060 adjacent opposite46Hall, Fig 3-15 47. BiomechanicsVector ResolutionAngle Sin Cos Trigonometric 0 0 1 30 0.500.873045 0.710.71opposite 1010 adjacent 55 0.820.57 8.78.7 60 0.870.5 90 1 060 adjacent opposite 5.05.047Hall, Fig 3-15 48. BiomechanicsVector ResolutionAngle Sin Cos Trigonometric 0 0 1 30 0.500.8720sin(55) = 16.4 45 0.710.71 55 0.820.57 60 0.870.5 90 1 0 55 20cos(55) = 11.448Hall, Fig 3-15 49. BiomechanicsVector ResolutionAngle Sin Cos Trigonometric 0 0 1 30 0.500.87 45 45 0.710.71 55 0.820.57 60 0.870.5 90 1 0 5530 Hypotenuse = 10049Hall, Fig 3-15 50. BiomechanicsVector Resolution Angle Sin Cos Trigonometric0 0 130 0.500.87 457145 0.710.717155 0.820.57 825060 0.870.590 1 0 55 5787 30 Hypotenuse = 100 50 Hall, Fig 3-15 51. BiomechanicsVector Resolution Angle Sin Cos Trigonometric0 0 1 How does angle change the composition? 30 0.500.8745 0.710.7155 0.820.5760 0.870.590 1 090 6045 30051 52. Biomechanics Module Application to human movement Resolve force into: Perpendicular force Rotation Parallel force Compression Position dependent perpendicularparallel52 53. Biomechanics Module End of Biomechanics Module Dont forget to take the quiz53