1. Mechanisms of Aerial Locomotion
    Falling- decreasing altitudes under gravity, no specializations for producing drag or lift- quickest way of escape for many animals

    Parachuting- vertical displacement under gravity, specializations for increasing drag, minimize terminal velocity to slow down

    • Gliding- lift generated without flapping, propulsion by jumping and gravity
    • “flying lemur”, “flying” squirell, “flying” snake, Alsomitra macrocarpa seed- low
    • terminal velocity

    Flying- lift generated by flapping, propulsion by flapping
  2. Pinnate Muscle
    • Advantages- lots of sacromeres in parallel, no bulge, eg. arthropod leg
    • Disadvantages- short escrusion, some force wasted due to fiber orientation
    • Image Upload 2
  3. Lift
    • A force in the direction perpendicular to traveling
    • Can be up or down
    • Generating by creating a circulatory force
    • Image Upload 4
  4. Bernoulli's Principle
    • An increase in flow (Ek) results in a decrease in pressure (Ep)
    • Force perpendicular to flow-Bernoulli's Effect
    • Extension of the law of conservation of energy.
    • Potential E in fluids is pressure and kenetic E is movement.
    • Can't maintain one if the other changes
    • In sponges, water flows over the top creating movement in the body of the sponge.
    • Image Upload 6
  5. Running
    • Spring loaded inverted pendulum model or pogo stick model
    • Image Upload 8
  6. Walking
    • Mechanical E= Potential E + Kenetic E
    • Image Upload 10
  7. Walking and Running
    • The basic components of efficent terrestrial locomotion.
    • A vector has both magnitude and direction.
    • Image Upload 12
  8. Trade off
    • Within a lever system a muscle can not have both a high mechanical advantage and a high velocity ration.
    • A muscle with a high mechanical advantage can increase speed by increasing muscle length.
    • A muscle with a high velocity ratio can increase force production by increasing cross sectional area.
    • Image Upload 14
  9. Velocity Ratio
    • L0/L1
    • The lever arms complete their arm movements during the same amount of time. A long lever has a greater displacement and so moves faster than a shorter lever.
    • Image Upload 16
  10. Mechanical Advantage
    • L1/L0
    • The longer the in level with respect to the out level, the higher the mechanical advantage and the more power the muscle can use against its load.
    • Image Upload 18
  11. Torque
    • product of force and lenght.
    • Can change even if L0 and L1 are constant
    • Image Upload 20
  12. Mechanics of a simple skeletomuscular system
    Image Upload 22
  13. Spindle shaped muscle
    • part parallel fibered part pinnate
    • a common compromise
    • Image Upload 24
  14. Parallel Fibered Muscle
    • Advantages- shorten rapidly, large excrusion
    • Disadvantages- bulges during contraction, relatively few sacromeres in parallel (low force)
    • Image Upload 26
  15. Design of Column and cylinders
    • Hollow cylindrical elements are strong and light
    • ex. arthrod leg segments, light poles, plant stems, vertebrate long bones
    • Image Upload 28
  16. Hydrostatic Skeleton
    • Abdomonial coelom is a fluid filled space that is pressurized to provide support during lifting to help expel feces. When the force is too high and/or the coelomic wall is too weak stuff comes out... inguinal hernia
    • Image Upload 30
  17. Design Principles of Skeletal Structures
    • Build structures with multiple layers to prevent propagation of cracks
    • Image Upload 32
    • Use composite materials- one good in compression and one good in tension
  18. Viscoelasticity
    • stress-strain relationships of biomaterials are often time dependent
    • Image Upload 34
  19. Compliance
  20. Rigidity
  21. Maximum extensibility
    The strain imposed on a material at failure
  22. Maximum Strength
    The stress impossed on a material at failure
  23. Stress Strain Curves
    Image Upload 36
  24. Kinds of Mechanical Forces
    Image Upload 38
  25. Autogyration
    • Lift production
    • The roboseed with samara from maple tree - spins around and chops air creating lift.
    • Form of natural selection to carry it away from the parent tree.
    • Image Upload 40
  26. Magnus Effect
    • High kenetic energy on top and less pressure on the bottom pushing it up.
    • Happens in curve balls and sail boats
    • Snapping shrimp claps. Gasses dissolve in water and it makes bubbles then the cavitation slams shut creating a very intense shock wave
    • Ailanthus tree (tree of heaven)- seed in the middle falls off the tree ans starts t twirl generating lift by autorotation. The horizontal force moves it away from the shadow of the tree

    Image Upload 42
  27. Airfoil
    • Nonrotating object that imposses rotation of air.
    • The speed of air increases over the curvator
    • As soon as wing tip passes,air circulates and begins circulating in a trail
    • Way of generating a magnus effect without spinning
    • Occurs in birds and airplanes
    • Image Upload 44
Card Set
Muscle architecture, movement, mechanical forces, properties, size and shape