Presentation is loading. Please wait.

Presentation is loading. Please wait.

KNR 352: Quantitative Analysis in Biomechanics Dr. Steve McCaw 227B438-3804 www.castonline.ilstu.edu/mccaw.

Similar presentations


Presentation on theme: "KNR 352: Quantitative Analysis in Biomechanics Dr. Steve McCaw 227B438-3804 www.castonline.ilstu.edu/mccaw."— Presentation transcript:

1 KNR 352: Quantitative Analysis in Biomechanics Dr. Steve McCaw 227B

2 Topics Basic Operations requiredBasic Operations required Dealing with vectorsDealing with vectors Review from 282 (Basic Biomechanics)Review from 282 (Basic Biomechanics) KinematicsKinematics Calculations of basic quantitiesCalculations of basic quantities Displacement, velocity, accelerationDisplacement, velocity, acceleration KineticsKinetics CalculationsCalculations GRF, CofP, JMFGRF, CofP, JMF EnergeticsEnergetics CalculationsCalculations Power, WorkPower, Work

3 Performance Injury

4 TASK Performance Injury

5 Task Factors Basic SkillBasic Skill WalkingWalking JumpingJumping Take off & LandingTake off & Landing RunningRunning Take off & LandingTake off & Landing What joint actions are occurring?What joint actions are occurring? What muscles are active?What muscles are active? What are the risks?What are the risks?

6 Task Factors Basic SkillBasic Skill Complex TaskComplex Task ThrowThrow Assembly TaskAssembly Task Curl upCurl up Hitting a baseballHitting a baseball What joint actions are occurring?What joint actions are occurring? What muscles are active?What muscles are active? What are the risks?What are the risks?

7 TASK Performance Injury Environment

8 Environmental Factors Weather/field/floor conditionsWeather/field/floor conditions Friction====>stability, tissue loadsFriction====>stability, tissue loads

9 Environmental Factors Weather/field/floor conditionsWeather/field/floor conditions GravityGravity space travel & platformsspace travel & platforms

10 Environmental Factors Weather/field/floor conditionsWeather/field/floor conditions GravityGravity Open/closed taskOpen/closed task dynamic vs. static environmentdynamic vs. static environment

11 Environmental Factors Weather/field/floor conditionsWeather/field/floor conditions GravityGravity Open/closed taskOpen/closed task Rules on the game/of the jobRules on the game/of the job # of players# of players field dimensionsfield dimensions workplace layoutworkplace layout temporal constraintstemporal constraints

12 TASK Performance Injury EnvironmentIndividual

13 Individual Factors Cognitive abilityCognitive ability

14 Individual Factors Cognitive abilityCognitive ability AnthropometricsAnthropometrics

15 Individual Factors Cognitive abilityCognitive ability AnthropometricsAnthropometrics Psychological statePsychological state

16 Individual Factors Cognitive abilityCognitive ability AnthropometricsAnthropometrics Psychological statePsychological state Fitness & HealthFitness & Health Skill levelSkill level

17 TASK Performance Injury EnvironmentIndividual

18 TASK Performance Injury EnvironmentIndividual

19 TASK Performance Injury EnvironmentIndividual Modulated by force: described by mechanics

20 Every structure that participates in the movement of the body does so according to physical and physiological principles. Hamilton & Luttgens, Kinesiology: Scientific basis of Human Motion, 10 th edition.

21 Mechanics influence of force on bodies Biomechanics: force on biological organismsBiomechanics: force on biological organisms biomechanics of fluidsbiomechanics of fluids circulation (lung, blood, artery)circulation (lung, blood, artery)

22 Mechanics influence of force on bodies Biomechanics: force on biological organismsBiomechanics: force on biological organisms biomechanics of fluidsbiomechanics of fluids biomechanics of deformable solidsbiomechanics of deformable solids bones, ligaments, tendonsbones, ligaments, tendons

23 Mechanics influence of force on bodies Biomechanics: force on biological organismsBiomechanics: force on biological organisms biomechanics of fluidsbiomechanics of fluids biomechanics of deformable solidsbiomechanics of deformable solids biomechanics of rigid bodiesbiomechanics of rigid bodies body as “rigid links” at “frictionless hinges”body as “rigid links” at “frictionless hinges”

24

25 Mechanics KinematicsKinematics description of pattern of motiondescription of pattern of motion how farhow far how fasthow fast how consistenthow consistent Kinetics

26 Mechanics KinematicsKinematics description of pattern of motiondescription of pattern of motion how farhow far how fasthow fast how consistenthow consistent temporal aspectstemporal aspects durationsdurations sequencingsequencing Kinetics

27 Mechanics KinematicsKinematics description of pattern of motiondescription of pattern of motion how farhow far how fasthow fast how consistenthow consistent temporal aspectstemporal aspects durationsdurations sequencingsequencing Kinetics study of forces that cause motion

28 Mechanics KinematicsKinematics description of pattern of motiondescription of pattern of motion how farhow far how fasthow fast how consistenthow consistent temporal aspectstemporal aspects durationsdurations sequencingsequencing Kinetics study of forces that cause motion magnitude direction line of action point of application

29 F = m a

30 Force CAUSES acceleration

31 F = m a Force CAUSES acceleration Force CAUSES injury

32 Fundamental Concepts for Biomechanical Analysis Units of Measure: ISU (International system of Units, ie the Metric System)Units of Measure: ISU (International system of Units, ie the Metric System)

33 Fundamental Concepts for Biomechanical Analysis Units of Measure: ISU (International system of Units, ie the Metric System)Units of Measure: ISU (International system of Units, ie the Metric System) Base UnitsBase Units length: meter (m)length: meter (m) mass: gram (g)mass: gram (g) time: second (s)time: second (s)

34 Motion Change in position of a body with respect to timeChange in position of a body with respect to time

35 Motion quantify POSITIONquantify POSITION location in 3D space: Plocation in 3D space: P three reference axes: X, Y, Zthree reference axes: X, Y, Z Cartesian system: axes at 90 o (orthogonal)Cartesian system: axes at 90 o (orthogonal)

36 ISB Convention: 2D X Y 0,0 Progression

37 ISB Convention: 3D X Y 0,0,0 Z Vertical Medio-Lateral Anterior-Posterior

38 Scalars and Vectors Scalar quantityScalar quantity described by magnitude alonedescribed by magnitude alone massmass volumevolume distancedistance speedspeed Vector quantity requires description of magnitude and direction force momentum impulse displacement velocity acceleration

39 Parallelogram Law for Addition of Vectors Sum of two vectors (resultant, R) equals the diagonal of the parallelogram with sides equal to the two vectors.Sum of two vectors (resultant, R) equals the diagonal of the parallelogram with sides equal to the two vectors. Draw on board, tail to tailDraw on board, tail to tail Triangle Rule: tip to tailTriangle Rule: tip to tail commutative: R = A + B = B + Acommutative: R = A + B = B + A Polygon Rule: extends to 3 or more vectorsPolygon Rule: extends to 3 or more vectors

40 Review: Basic Trigonometry Right angle TriangleRight angle Triangle naming conventionsnaming conventions Pythagorean TheoremPythagorean Theorem Trig functionsTrig functions Sine, Cosine, Tangent (slope)Sine, Cosine, Tangent (slope) Inverse TangentInverse Tangent

41 Coordinate Systems Rectangular or Cartesian Coordinate SystemRectangular or Cartesian Coordinate System P = P x + P yP = P x + P y Polar coordinate systemPolar coordinate system P = r and ӨP = r and Ө Polar to rectangularPolar to rectangular (use SOH and CAH)(use SOH and CAH) Rectangular to PolarRectangular to Polar use Pythagorean Thereom and arctanuse Pythagorean Thereom and arctan Examples: P to R: degrees R to P: F v = 1300 N & F A/P = 100 N

42 Adding Force (vectors) by Summing Components Force: magnitude & direction need to be calculatedForce: magnitude & direction need to be calculated

43 Adding Force (vectors) by Summing Components Force 1 = 50 N at -45 degreesForce 1 = 50 N at -45 degrees Force 2 = 30 N at 90 degreesForce 2 = 30 N at 90 degrees Solve for Resultant

44 Adding Force (vectors) by Summing Components Force 1 = 50 N at -45 degreesForce 1 = 50 N at -45 degrees Force 2 = 30 N at 90 degreesForce 2 = 30 N at 90 degrees Force 3 = 75 N at 28 degreesForce 3 = 75 N at 28 degrees Force 4 = 15 N horizontal & 13 N verticalForce 4 = 15 N horizontal & 13 N vertical Solve for Resultant

45 New & Useful Information Radian – the angle created by the arc on a circle with the length of the radius of the circle (~ 57.3 degrees) Arc length = 1 radius

46 Calculate the resultant force from Coracobrachialis and Pectoralis Major Coracobrachialis = 1200 N, PM = 1700 N

47 Effect of tension development on angle of muscle insertion and muscle activation level. Given: Muscle force = 90 N /cm 2 x-sectional area X-sectional area = 4 cm 2 Muscle Ө relaxed = 50° Muscle Ө active = 85° Required: 150 N force along tendon Calculate: Percentage of max muscle force developed to produce the 150 N of force.

48 Additional Problems Available from web

49 Motion Change in position of a body with respect to timeChange in position of a body with respect to time quantify POSITIONquantify POSITION quantify TIMEquantify TIME Motion-capture systems

50 Motion Capture Pre 1985: FilmPre 1985: Film RedLake Locam: 500 fpsRedLake Locam: 500 fps ~ $125 roll (film + developing)~ $125 roll (film + developing) Working in the “dark”Working in the “dark” RecordRecord Send for processingSend for processing Hope it all turns out ok.Hope it all turns out ok. All black, badly focused, missed critical eventAll black, badly focused, missed critical event Manual DigitizingManual Digitizing

51 Motion Capture Pre 1985: FilmPre 1985: Film Post 1985: High speed videoPost 1985: High speed video Immediate feedbackImmediate feedback Easy to adjustEasy to adjust Reduced cost (once system paid for)Reduced cost (once system paid for) Auto Digitizing AvailableAuto Digitizing Available

52 Example Video

53 Reflective Markers

54 Motion Capture Pre 1985: FilmPre 1985: Film Post 1985: High speed videoPost 1985: High speed video Post 1990: Active Marker SystemsPost 1990: Active Marker Systems No visible recording of performerNo visible recording of performer Tracks x,y coordinates of markers onlyTracks x,y coordinates of markers only FAST.FAST. $$$$$$$$

55 Principles of Recording 1.Maximize image size within field of view. Field of view: rectangular area recorded Field Height Field Width Field Depth

56 Photographic Dimensions

57 Principles of Recording 1. Maximize image size within field of view. Optimize calibrated volume. Volume: Height x Width x Depth.

58 Principles of Recording 1.Optimize calibrated volume 2.Ensure always within field of view

59 Principles of Recording 1.Optimize calibrated volume 2. Ensure always within field of view Stay within calibrated volume 1.Landing 2.Run 3.Jump

60 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3.Ensure adequate pre and post recording  Torry’s 16 mm thesis recording 1.Landing: air time, post max knee (max extension) 2.Lifting (bench & squat): before descent, post ascent Video Tapes are Cheap

61 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3. Ensure adequate pre and post recording  Torry’s 16 mm thesis recording Capture adequate pre-initial and post-final activity 1.Landing: air time, post max knee (max extension) 2.Lifting (bench & squat): before descent, post ascent Server space is Cheap

62 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3. Ensure adequate pre and post recording Capture adequate pre-initial and post-final activity  Important for video processing 1.Smoothing process

63 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3.Capture adequate pre-initial and post-final activity 4.Use as slow a video speed as feasible Standard video: 30 frames per secondStandard video: 30 frames per second High speed: 60, 120  2000 fpsHigh speed: 60, 120  2000 fps Lo speed = Improved quality of recording Hi speed = capture more frames of activity

64 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3.Capture adequate pre-initial and post-final activity 4. Use as slow a video speed as feasible Set at 200 fps. Ensure an even multiple of EMG or GRF (??)

65 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3.Capture adequate pre-initial and post-final activity 4.Set at 200 fps. 5.Make shutter speed as short as possible Too short: not enough light Too long: “comets” rather than round markers

66 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3.Capture adequate pre-initial and post-final activity 4.Set at 200 fps. 5. Make shutter speed as short as possible Too short: not enough light Too long: “comets” rather than round markers

67 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3.Capture adequate pre-initial and post-final activity 4.Set at 200 fps. 5.Make shutter speed as short as possible 6.Depth of field 1.Is 2D an appropriate assumption? 2.ISU Lab: record 3D even if 2D is of interest

68 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3.Capture adequate pre-initial and post-final activity 4.Set at 200 fps. 5. Make shutter speed as short as possible 6.Depth of field 1.Is 2D an appropriate assumption? 2.ISU Lab: record 3D even if 2D is of interest

69 Principles of Recording 1.Optimize calibrated volume 2.Stay within calibrated volume 3.Capture adequate pre-initial and post-final activity 4.Set at 200 fps. Pilot Test

70 Calibration Real Life recorded on VideoReal Life recorded on Video Scale video dimensions to real lifeScale video dimensions to real life 2D: set up camera, record known length in plane of action2D: set up camera, record known length in plane of action Perpendicular alignment is criticalPerpendicular alignment is critical Scaling factorScaling factor Digitize recording of rulerDigitize recording of ruler Sf = actual length (m) / digitized length (arbitrary units)Sf = actual length (m) / digitized length (arbitrary units)

71 Calibration Real Life recorded on VideoReal Life recorded on Video Scale video dimensions to real lifeScale video dimensions to real life 2D: set up camera, record known length in plane of action2D: set up camera, record known length in plane of action 3D: set up cameras, record calibration Wand and calibration triangle on Force Platform.3D: set up cameras, record calibration Wand and calibration triangle on Force Platform.

72 Marker Selection Where to put the reflective markers?Where to put the reflective markers? What are you measuring?What are you measuring? Segments & joints of interestSegments & joints of interest Lower Body?Lower Body? Upper Body?Upper Body? Trunk?Trunk? Stick figure of landing in sagittal plane

73 Marker Selection Where to put the reflective markers?Where to put the reflective markers? What are you measuring?What are you measuring? Segments & joints of interestSegments & joints of interest Lower Body?Lower Body? Upper Body?Upper Body? Trunk?Trunk? Stick figure of landing in sagittal plane

74 Marker Selection Where to put the reflective markers?Where to put the reflective markers? What are you looking at?What are you looking at? Landmarks defining segment endpointsLandmarks defining segment endpoints

75 Marker Selection Where to put the reflective markers?Where to put the reflective markers? What are you looking at?What are you looking at? Landmarks defining segment endpointsLandmarks defining segment endpoints ISU Lab All landings on force platform Spatially synchronized within calibration grid No need for markers on floor

76 Motion Change in position of a body with respect to timeChange in position of a body with respect to time quantify POSITIONquantify POSITION quantify TIMEquantify TIME Linear Motion: translation rectilinear curvilnear

77 Motion Change in position of a body with respect to timeChange in position of a body with respect to time quantify POSITIONquantify POSITION quantify TIMEquantify TIME Linear Motion: translation rectilinear: straight line curvilnear: curved line (parabolic)

78 Motion Change in position of a body with respect to timeChange in position of a body with respect to time quantify POSITIONquantify POSITION quantify TIMEquantify TIME Linear Motion Angular Motion: rotation

79 Motion Change in position of a body with respect to timeChange in position of a body with respect to time quantify POSITIONquantify POSITION quantify TIMEquantify TIME Linear Motion Angular Motion General motion

80 Motion Change in position of a body with respect to timeChange in position of a body with respect to time quantify POSITION: from motion trackerquantify POSITION: from motion tracker quantify TIME  ?quantify TIME  ? Linear Motion Angular Motion General motion

81 Time in Video Analysis 200 images per second200 images per second 1 second / 200 frames = seconds between frames1 second / 200 frames = seconds between frames

82 Motion Position: location in spacePosition: location in space Displacement (distance)Displacement (distance) change of positionchange of position

83 Motion Position: location in spacePosition: location in space Displacement (distance)Displacement (distance) change of positionchange of position Velocity (speed)Velocity (speed) change of position with respect to timechange of position with respect to time This is motionThis is motion

84 Motion Position: location in spacePosition: location in space Displacement (distance)Displacement (distance) change of positionchange of position Velocity (speed)Velocity (speed) change of position with respect to timechange of position with respect to time This is motionThis is motion AccelerationAcceleration change of velocity = change of motionchange of velocity = change of motion

85 Force Push or pull exerted by one body on another body that causes or tends to cause a change in motion of each bodyPush or pull exerted by one body on another body that causes or tends to cause a change in motion of each body

86 Force a derived unit in mechanicsa derived unit in mechanics body: massbody: mass change in motion: accelerationchange in motion: acceleration new location in space and timenew location in space and time 1 newton = 1 N = 1 kg m / s / s

87 Mass Quantifies linear inertiaQuantifies linear inertia resistance of a body to a change in linear motionresistance of a body to a change in linear motion AnthropometryAnthropometry measure of body dimensionsmeasure of body dimensions ht, wt, girth, segment length, densityht, wt, girth, segment length, density Body Segment ParametersBody Segment Parameters mass, center of mass (gravity), radius of gyrationmass, center of mass (gravity), radius of gyration


Download ppt "KNR 352: Quantitative Analysis in Biomechanics Dr. Steve McCaw 227B438-3804 www.castonline.ilstu.edu/mccaw."

Similar presentations


Ads by Google