Flying- lift generated by flapping, propulsion by flapping
Advantages- lots of sacromeres in parallel, no bulge, eg. arthropod leg
Disadvantages- short escrusion, some force wasted due to fiber orientation
A force in the direction perpendicular to traveling
Can be up or down
Generating by creating a circulatory force
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.
Spring loaded inverted pendulum model or pogo stick model
Mechanical E= Potential E + Kenetic E
Walking and Running
The basic components of efficent terrestrial locomotion.
A vector has both magnitude and direction.
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.
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.
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.
product of force and lenght.
Can change even if L0 and L1 are constant
Mechanics of a simple skeletomuscular system
Spindle shaped muscle
part parallel fibered part pinnate
a common compromise
Parallel Fibered Muscle
Advantages- shorten rapidly, large excrusion
Disadvantages- bulges during contraction, relatively few sacromeres in parallel (low force)
Design of Column and cylinders
Hollow cylindrical elements are strong and light
ex. arthrod leg segments, light poles, plant stems, vertebrate long bones
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
Design Principles of Skeletal Structures
Build structures with multiple layers to prevent propagation of cracks
Use composite materials- one good in compression and one good in tension
stress-strain relationships of biomaterials are often time dependent
The strain imposed on a material at failure
The stress impossed on a material at failure
Stress Strain Curves
Kinds of Mechanical Forces
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.
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
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
Muscle architecture, movement, mechanical forces, properties, size and shape