carbon nanotube (cnt) aerogel muscles
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Yi Rao, UC Berkeley 1
Carbon Nanotube (CNT) Aerogel Muscles
Yi Rao
May 4th, 2008
Yi Rao, UC Berkeley 2
By Ray H. Baughman, UT Dallas
Natural Muscle CNT AerogelDensity (kg/m3) 1037 1.5
Strain (%) 20-40 220
Strain Rate (%/s) 50 3.7×104
Stress (MPa) 0.1-0.35 3.2
Work per Cycle (J/Kg) 40 30
Operating temp. (K) Ambient 80-1900
Cycle Life * 106k 140k
Yi Rao, UC Berkeley 3
Preparation of CNT Aerogel Sheet Actuator
CNT Aerogel Sheet is drawn from straight sidewalls of MWNT Speed: 2m/s Outer diameter: 12nm with 9 walls
MWNT forest were synthesized by catalytic CVD
Yi Rao, UC Berkeley 4
Measurement of Actuation
The CNT sheet is expanded by change repulsionApply voltage to positively charge to CNT sheet
Changes is recorded by optical diffraction
Yi Rao, UC Berkeley 5
Actuation in width and thickness directionVoltage, L/W ratio and temperature dependence
Sheets num
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Operating at resonance with low voltage
Q is 455, the strain can be 30% with Vrms=10V
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Actuation in the length direction (Strength)
Different applied voltageto width expansion
Stress on length direction and work capacity
Yi Rao, UC Berkeley 8
Conclusion and Drawback
The CNT Aerogel muscle shows some amazing properties compared with human muscle
Strain, Strain Rate, Stress Density Temperature tolerance
But there are still some concerns The material volume is not large and dense enough for real use The property of CNT sheet becomes worse when add more layers The apply voltage on low frequency is too large Very high cost ($100/g)
Yi Rao, UC Berkeley 9
Complementary: Aerogel Aerogel is a solid-state material with the lowest known density Aerogel is gel in which the liquid component of the gel has been
replaced with gas. Aerogel is thermal insulator
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