kin 221 - module BA instrumentation and signals

data integrity

instrumentation is important as ____________ helps the signal being collected representing what is being measured

amplitude

the max angle/range a segment travels/moves

frequency

the number of times a segment moves in a cycle

unrestricted

found in healthy people and will have a smaller shear forces in the joints

restricted

often found in unhealthy people and has increased shear forces on joints

analog signal

a transducer turns mechanical into electrical also known as a ______________

transducer

device that converts a form of energy into another

false

transducer will convert electrical to electrical or mechanical

\
t or f

force plate

____________ converts mechanical deformation into electrical energy

LVDT

_____________ converts displacement into electrical energy

continuous

analog information is ______________

discrete

digital information is _______________

true

a computer can only handle digital/binary information, thus analog turns to digital

\
t or f

temporal synchronization

2 devices (ex: video and FP) are synched in respect to time

FP frame = (vid frame-1)\* ratio +1

the equation of a FP frame is _________________

9

if the ratio is 4 FP frames per video frames, then at video frame 3, what is the forceplate frame

17

if the ratio is 4 FP frames per video frames, then at video frame 5 , what is the forceplate frame

false

the sampling frequency should be less than twice the highest frequency

\
t or f

too much data

if the sampling rate is too high then there is

aliasing/erroneous data

if the sampling rate is too low then there is

true

aliasing involves what was being sampled not matching what happened in real life

\
t or f

summation

____________ is the addition of different curves of data with different frequencies

fourier analysis

breaks signal into components (sin waves) with different frequencies

121 Hz

if the signal has a 60 Hz sinewave as it’s highest component what should the sampling frequency

21

if the signal has a 10 Hz sinewave as it’s highest component what should the sampling frequency be

noise

physiological signals are rarely separate from other interfering signals called

systemic noise

this noise is caused from not zeroing the equipment before use

random noise

this noise cannot be corrected and is from soft tissue artifact