Biomechanics - ENGG 3150 - Final Exam Prep
- Looks at forces acting on
a biological structure
- Looks at the effects of
What is Biomechanics?
those forces on structures
- Multidisciplinary
- Trying to quantify forces
- Movement of a segment
What 3 elements can be
- Tissue Deformation
studies by looking at external
- Tissue Adaption
and internal Forces?
Concentric Contractions contraction shortens your muscle as it acts against resistive force (like
a weight).
muscles lengthen while producing force—usually by
Ecentric Contractions
returning from a shortened (concentric) position to a
resting position.
What type of tissue stabilizes Ligaments
joints in the body?
- Right to privacy and non-participation
Name the 3 rights of - Right to remain anonymous
participants? - Right to confidentiality
, - Strain gauge sends out signal
- As it bends, more light is
transmitted and this
How does a corresponds to degree
Goniometer Work? Are angles
Goniometers Linear?
How many calibration points - Yes they are linear
should be used?
How should it be calibrated? - 6 to 8 points is advised
- If the ROM being tested is 0 to 180 degrees, it would be
best to calibrate between these 2
degree values. Interpolation is desired over extrapolation.
What is R^2? - Coefficient of determination
What is the desirable value? - 0.9 +
2x10^12 = 4096 bit
10 V/4096 bits = 0.0024 V/bit
Powered by a 5 volt source,
the goniometer can be used
Goniometer is powered by a 5
between 0 and 190 degrees.
volt source A/D card has a 10
The goniometer is connected
volt range.
to a 12 bit A/D card which So the Goniometer only uses ½ of the full bit range
allows input voltages of 0 to 10
volts. Calculate the number of So 4096 bit / 2 = 2048 bits
bits/degree. If you need to be 2048 bits / 190 degrees = 10.8 bits/degree
able to resolve 2 degrees, is
the number of bits/degree This is good because we want a couple of degrees as
acceptable (briefly justify your opposed to 1 degree so that we are able to differentiate
answer)? (2 Marks) between degrees
- Half the Sampling rate or two times the size of the
What is Nyquist's
highest frequency content in the signal
Theorem? Why is it
- Confident is the representation of the signal because it is
used?
represented with minimized noise
If you want to increase signal
- Sample much higher - 100 Hz
clarity, what do you do?
What does increasing the - Reduces the attenuation and results in a sharper roll off
filter order do? Are there and over all a sharper looking signal, therefore the rate
risks with high filter orders? of attenuation is much lower
If the resulting signal after - Yes, you risk over filtering the data and losing the integrity of the
original signal
filtering is distorted at the start
- represented with minimized noise
and end, what can you do?
- You can pad with extra data at the start and end
What 2 instruments were - LP: Goniometers and VICON
used with Low Pass filters and - HP: EMG
name 1 for High Pass?
- The higher the cutoff frequency, the closer the signal is to the
How to choose an appropriate original signal
- To high can allow for noise to come thru and loo low
cut-off frequency?
can eliminate parts of the signal
- Looks at forces acting on
a biological structure
- Looks at the effects of
What is Biomechanics?
those forces on structures
- Multidisciplinary
- Trying to quantify forces
- Movement of a segment
What 3 elements can be
- Tissue Deformation
studies by looking at external
- Tissue Adaption
and internal Forces?
Concentric Contractions contraction shortens your muscle as it acts against resistive force (like
a weight).
muscles lengthen while producing force—usually by
Ecentric Contractions
returning from a shortened (concentric) position to a
resting position.
What type of tissue stabilizes Ligaments
joints in the body?
- Right to privacy and non-participation
Name the 3 rights of - Right to remain anonymous
participants? - Right to confidentiality
, - Strain gauge sends out signal
- As it bends, more light is
transmitted and this
How does a corresponds to degree
Goniometer Work? Are angles
Goniometers Linear?
How many calibration points - Yes they are linear
should be used?
How should it be calibrated? - 6 to 8 points is advised
- If the ROM being tested is 0 to 180 degrees, it would be
best to calibrate between these 2
degree values. Interpolation is desired over extrapolation.
What is R^2? - Coefficient of determination
What is the desirable value? - 0.9 +
2x10^12 = 4096 bit
10 V/4096 bits = 0.0024 V/bit
Powered by a 5 volt source,
the goniometer can be used
Goniometer is powered by a 5
between 0 and 190 degrees.
volt source A/D card has a 10
The goniometer is connected
volt range.
to a 12 bit A/D card which So the Goniometer only uses ½ of the full bit range
allows input voltages of 0 to 10
volts. Calculate the number of So 4096 bit / 2 = 2048 bits
bits/degree. If you need to be 2048 bits / 190 degrees = 10.8 bits/degree
able to resolve 2 degrees, is
the number of bits/degree This is good because we want a couple of degrees as
acceptable (briefly justify your opposed to 1 degree so that we are able to differentiate
answer)? (2 Marks) between degrees
- Half the Sampling rate or two times the size of the
What is Nyquist's
highest frequency content in the signal
Theorem? Why is it
- Confident is the representation of the signal because it is
used?
represented with minimized noise
If you want to increase signal
- Sample much higher - 100 Hz
clarity, what do you do?
What does increasing the - Reduces the attenuation and results in a sharper roll off
filter order do? Are there and over all a sharper looking signal, therefore the rate
risks with high filter orders? of attenuation is much lower
If the resulting signal after - Yes, you risk over filtering the data and losing the integrity of the
original signal
filtering is distorted at the start
- represented with minimized noise
and end, what can you do?
- You can pad with extra data at the start and end
What 2 instruments were - LP: Goniometers and VICON
used with Low Pass filters and - HP: EMG
name 1 for High Pass?
- The higher the cutoff frequency, the closer the signal is to the
How to choose an appropriate original signal
- To high can allow for noise to come thru and loo low
cut-off frequency?
can eliminate parts of the signal
