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Title: Bistable electroactive polymers for refreshable tactile displays
Bistable electroactive polymers (BSEP) combine shape memory with large-strain actuation at the rubbery state to achieve rigid-to-rigid actuation. The stiffness of the BSEP is tunable via glass transition or phase changing. The reversible melting-crystallization of the polymer chains in the phase changing BSEP contributes to the stiffness change within a narrow temperature range. A modulus change of more than 1000 folds can be achieved within 3 °C. Additionally, large actuation strains rivaling those of VHB acrylic elastomers can be obtained at the rubbery state. Explorations regarding potential applications of this material have been focused on tactile displays. In one design, Joule heating of a serpentine-shaped compliant electrode coated on a BSEP film, coupled with a pneumatic pressure source has been employed to raise diaphragm dots with 1.5 mm base diameter to heights up to 0.7 mm. The resulting Braille electronic readers could thus be actuated with low voltages.  more » « less
Award ID(s):
1700829
PAR ID:
10140226
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Proc. SPIE 10966, Electroactive Polymer Actuators and Devices (EAPAD) XXI
Volume:
10966
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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