Biomechanics Biomechanics

Biomechanics
•  applies mechanics to biology
•  physiological and medical
applications are the main points
in this course
Biomechanics
Biomechanics is the science
that examines forces acting
upon and within a biological
structure and effects produced
by such forces.
B.M. Nigg
Historical background
! Leonardo da Vinci, 1452-1519
! Andreas Vesalius, 1514-1564
! Galileo Galilei, 1564-1642
! William Harvey, 1578-1658
! René Descartes, 1596-1650
! Giovanni Alfonso Borelli, 1608-1679
! Robert Boyle, 1627-1691
! Robert Hooke, 1635-1703
! Isac Newton, 1642-1727
! Leonard Euler, 1707-1783
! Thomas Young, 1773-1829
! Jean Poiseuille, 1797-1869
! Adolf Fick, 1829-1901
! ....
Leonardo da Vinci
1
Andreas Vesalius
Galileo Galilei, 1564-1642
Anathomic theatre, Leyden 1610
2
William Harvey, 1578-1658
Giovanni Alfonso Borelli,
1608-1679
The way of solving a Biomechanical problem
2. What about the loading ?
0. Description of the anatomy, the CAD-drawing.
1.  How does the construction work mechanically ?
Kinematics
Limitations
Anatomy
Equations of equilibrium (forces)
Equations of equilibrium (moments)
Outer forces
3
2. What about the loading?
It is not obvious that the position follows
unambiguous from the loading !
ONLY PASSIVE ELEMENTS
Compression
Loading
Tension
The position is given from
the loading
Ligament
Bending
Cartilage
Compression
Loading
Tension
Bending
WITH ACTIVE ELEMENTS
Internal forces
The position can be completely different even if the
loading is the same
3. Constitutive relations
Assistive technology, can it be an advantage?
STRESS
STRAIN
STRESS
COMPACT
BONE
(APATITE
AND
COLLAGEN
Mechanical properties of the
most important constituents
of bone, muscles, tendons,
ligaments, cartilage etc.
TENDON
(COLLAGEN)
STRAIN
4