TY - GEN
T1 - The contribution of air to ultrasonic friction reduction
AU - Friesen, Rebecca Fenton
AU - Wiertlewski, Michael
AU - Peshkin, Michael A.
AU - Colgate, J. Edward
N1 - Funding Information:
This work was made possible by funding from NSF Grant IIS-1302422. MW acknowledges the support of ANR-16-CE33-0002-01.
Publisher Copyright:
© 2017 IEEE.
PY - 2017/7/21
Y1 - 2017/7/21
N2 - The origin of friction reduction on an ultrasonically vibrating plate has been the subject of debate. Recent work suggests that friction may be reduced due to intermittent contact caused by bouncing upon the vibrating surface [1], leaving the question of whether other phenomena such as levitation on a squeeze film of air also play a role. To probe the contribution of squeeze film levitation, we investigated the dependence of the friction reduction effect upon air pressure. An artificial finger was placed inside a vacuum chamber, touching an ultrasonic friction reduction device composed of a glass plate vibrated by piezo-actuators. Friction between the finger and the glass was measured by rotating the finger with a motor, and measuring the motor's torque load. Decreased friction is signaled by decreased motor current. Compared to atmospheric pressure, a 98% vacuum inside the chamber was observed to markedly diminish the friction reduction effect, suggesting that squeeze film levitation does indeed play a substantial role in ultrasonic friction reduction.
AB - The origin of friction reduction on an ultrasonically vibrating plate has been the subject of debate. Recent work suggests that friction may be reduced due to intermittent contact caused by bouncing upon the vibrating surface [1], leaving the question of whether other phenomena such as levitation on a squeeze film of air also play a role. To probe the contribution of squeeze film levitation, we investigated the dependence of the friction reduction effect upon air pressure. An artificial finger was placed inside a vacuum chamber, touching an ultrasonic friction reduction device composed of a glass plate vibrated by piezo-actuators. Friction between the finger and the glass was measured by rotating the finger with a motor, and measuring the motor's torque load. Decreased friction is signaled by decreased motor current. Compared to atmospheric pressure, a 98% vacuum inside the chamber was observed to markedly diminish the friction reduction effect, suggesting that squeeze film levitation does indeed play a substantial role in ultrasonic friction reduction.
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U2 - 10.1109/WHC.2017.7989955
DO - 10.1109/WHC.2017.7989955
M3 - Conference contribution
AN - SCOPUS:85034213617
T3 - 2017 IEEE World Haptics Conference, WHC 2017
SP - 517
EP - 522
BT - 2017 IEEE World Haptics Conference, WHC 2017
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 7th IEEE World Haptics Conference, WHC 2017
Y2 - 6 June 2017 through 9 June 2017
ER -