Lab meeting update Samson Phan Sept 24, 2010. In the beginning…
Lab meeting update
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Lab meeting update Samson Phan Sept 24, 2010
description
Lab meeting update. Samson Phan Sept 24, 2010. In the beginning…. Conclusions. HIC numbers associated with collisions are insufficient to cause concussions HIC & concussions: are they really a good measure? Automotive Laceration scales are too insensitive. - PowerPoint PPT Presentation
Transcript of Lab meeting update
Lab meeting update
Samson Phan Sept 24, 2010
In the beginning…
Conclusions
• HIC numbers associated with collisions are insufficient to cause concussions– HIC & concussions: are they really a good
measure?
• Automotive Laceration scales are too insensitive.
• Automotive based injury indices insufficient for robot human collisions
So we built a model…
02
46
810
0
0.05
0.110
4
106
108
1010
velocityrobot radii
Ma
teri
al p
rop
ert
y fu
nct
ion Wassink et al
µ = 0.4
µ = 0.8
Bruise Volumes
And a sensor…
Sensor ResultsNormal 30 degrees
68.2 68.25 68.3 68.35 68.4 68.45 68.5 68.55
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50
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data1
data2
data3
data4
146.05 146.1 146.15 146.2 146.25 146.3 146.35
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600
800
1000
data1
data2
data3
data4
Why similar patterns?Sensors are spaced too far?Sensors are not being sampled quickly enough?
Capacitance Leakage?
225 230 235 240 245 250
-100
-50
0
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Capacitance Leakage?Sensor # No touch
Freq (KHz)Finger TouchFreq (KHz)
Pen TouchFreq (KHz)
Delta between Finger and Pen
1 640 507 480 27
2 663 542 490 52
3
4 809 700 580 120
5 720 600 500 100
6 960 740 730 10
7 760 645 600 45
8 865 680 640 40
Inertia Coupling
Frequency Stiffnes Experimental (by Sami Haddadin)
Theory
High High Ilower Ilower+xIupper
High Low Ilower Ilower
Low High Ilower+Iupper Ilower+Iupper
Low Low Ilower+xIupper Ilower+xIupper
0<x<1
Questions
• Why the difference between theory and experiment (if it really exists)– Zero Order Hold? Backlash?– Is there a response rate threshold that is deleterious?– What happens when reaction time is less than collision
time?• Does the source of stiffness matter?
– Preliminary results suggests so– How do hydraulics/pneumatics (PAMS) behave?
(0<x<1)• Initial operating pressure variations
Future Work
• Conduct Collision Tests with Adept Setup to see varying effects of stiffness on Inertia coupling
• Use HSR arm setup to explore stiffness source effects. – Pneumatics, electromagnetic
motors
Experimental Setup
Adept Setup HSR Setup
How does stiffness affect collision?
Want to know more?HSR meeting @4 pm in Gates
GOOD LUCK SAL!
