Foundations of biomechanics Flashcards
Basic biomechanic principles
What is the study of kinematics?
It describes the spatial and temporal components of motion
What are the two types of kinematics?
Linear/translational and angular
What is translational motion?
Motion along a line, where all points on a body/object move the same distance, the same direction, at the same time
Does linear motion have to be in a straight line?
No, it can either be rectilinear (traditional, straight line), or curvilnear (follows a curved path)
What is angular motion?
Motion around an axis (the joints of the body)
What is general motion?
It is a combination of linear and angular motion. E.g. in cycling, the torso is in linear motion, whilst the lower limbs are in angular
How can kinematic data be collected?
Accelerometers, high-speed photographs, high-speed video/optoelectric system, digital positional data
What is an optoelectric system?
Method whereby markers are placed on relevant points of the limb to track motion. The markers emit signals which are picked up by cameras and informs them of their position in space, allowing a digitisation to be formed of the movement.
What does a Spatial Reference System show, and what method is used?
It shows the position-location of a body in space at some instant of time, typically using the Cartesian Coordinate System (both 2D and 3D)
What is a scalar measurement? Examples too.
Provides only magnitude. E.g. speed, mass
What is a vector measurement? Examples too.
Provides both magnitude and direction. E.g. velocity, acceleration, weight
What is the formula for velocity?
Displacement/time
What does running kinematics measure?
Analyses running gait by stride length and stride rate, providing speed
How does one read a velocity graph?
By the slope. +ve and -ve slopes indicate the responding velocity, whilst gradient of 0 typically indicates a change in direction
What is the first central method formula?
V xi = (xi+1 - xi-1)/2dt
What is the study of kinetics?
It is the study of the causes of motion
What is the formula for Newtons?
1N = 1kg*1.0m.s^-2 as F=ma