Transcript Final Presentation 2804 kb Friday, December 7

Need for Ergometer in Research
 Blood Flow Research and Analysis
 Quantifiable Client Specifications
 Ergometer Construction
 Challenges and Solutions
 Testing and Conclusions
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Device to facilitate blood flow analysis during
exercise
Femoral artery is imaged using ultrasound
Test subject will use the ergometer to
maintain a kicking motion against a constant
workload
Leg must passively return to original position
No commercially available device
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Metabolic, neural, and mechanical influences
on control of blood flow
◦ Altered by age or disease
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Discovery of natural chemicals’ role such as
adenosine and its effects on blood flow
Cardiovascular disease associated with blood
flow abnormality
Can exercise restore normal blood flow?
Drug companies can develop drugs to mimic
effects of exercise
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Measure blood flow
in femoral artery
Examine how smaller
blood vessels
regulate upstream
(femoral) blood flow
Infuse drugs into the
femoral artery to
isolate blood
pathways
http://www.gehealthcare.com/usen/ultrasou
nd/images/cmeadi_fig3_500.jpg
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Custom-made cycle
for use in MRI
◦ Wood and plastic
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Image blood flow
during exercise
Compare healthy
individuals to those
with vascular disease
Cycle ergometer prototype
for use in MRI at Stanford
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Part of a Monark
exercise bike and
a car seat
Rollerblade boot
with the toe cut
out
Device was
unreliable, and
had variable
forces
Altered Monark stationary
bike in use at Mayo Clinic
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Constant wattage (range 0-100 W)
Kick rate 30-60 KPM
Chair positioned 30º from vertical
Adjust for heights 5’4” to 6’4”
Flexible range of motion while kicking
◦ 90˚ - 180˚ range
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Passive return to rest position
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Output to computer through Powerlab and a
BNC cable
Adjustable workload
Under $2,000
Easily portable (with wheels)
Minimum lifespan of five years
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Frame built from steel pipe
Car seat fastened to frame
◦ Adjustable for proper subject placement
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Snowboard binding to connect foot to
resistance
Aluminum bar to connect boot to crank arm
Ball joints allow for lateral deviation during kick
Crank arm connects pulley to aluminum bar
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Brake attached to pulley via belt
Servo motor adjusts magnetic brake force
Console used to electronically adjust motor
settings through servo motor
Kicking motion propels crank arm
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PowerLab interface for kick rate data
Sensor to detect rotations of the pulley
Each drop in voltage corresponds to one kick
Distance (time) between voltage drops
determines kick rate
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Subject size and pedal bar length
Passive leg return-EMG screenshot
Consistent work load and power output
Ten minute stability test
New crank arm
Force transducer in pedal bar
No EMG activity
(passive return)
Rectus
Femoris
Vastus
Lateralis
Vastus
Medialis
Low Resistance
High Resistance
Multiple holes to
allow for adjustable
range of motion
12"
Item
Amount
Mc Master-Carr Order#1
•Clamps to attach seat
•Steel tubes to mount pulley
•Steel sheet to mount brake
$208.50
Mc Master-Carr Order#2
•Washers
•Ball joint linkages
•Threaded pedal bars
$72.54
Mc Master-Carr Order#3
•Alternate length pedal bars
$29.24
Home Depot
•Nuts and Bolts
Total (This semester)
Last Semester’s Total
Grand Total
$5.00
$315.28
$335.00
$650.28
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Maximal Perfusion of Skeletal Muscle in Man (Per Andersen
and Bengt Saltin) 1984
Chi-hua Fitness Co., Ltd.
http://www.chihua.com.tw/English/MAIN.htm
Joe Halfen, Director of Quality, Octane Fitness
Custom MRI cycle tracks blood flow during exercise
http://ability.stanford.edu/Press/mricycle.html
Role of adenosine in regulating the heterogeneity of skeletal
muscle blood flow during exercise in humans
http://jap.physiology.org/cgi/content/full/103/6/2042
Additional Thanks To:
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Lab of Pulmonary Medicine
Ken Ma
ECB Shop