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Title: Surface roughness effects on ionic polymer-metal composite (IPMC) sensitivity for compression loads
The soft and compliant nature of ionic polymer-metal composite (IPMC) sensors has recently been investigated for various applications in soft robotic and mechatronic devices. Recent results of physics-based chemoelectromechanical modeling suggest that IPMC asymmetric surface roughening may enhance the sensitivity under compression. This paper presents initial experimental results on IPMC compression sensors fabricated with varying degrees of asymmetric surface roughness. The roughness is created through a simple mechanical sanding process on the base polymer material, referred to as "polymer abrading technique'", followed by traditional electroless plating to create electrodes. Sample sensors are characterized by measuring the voltage response under different compressive loads. The results show consistently increased sensor sensitivity of the asymmetrically roughened IPMCs versus a control sample. Sensitivity increases non-monotonically with rougher electrode surfaces, where maximum sensitivity of about 0.0433 mV/kPa is achieved with sensor electrodes with 53-74~micrometer abrasions. More variability is also observed through augmented electrode roughness, suggesting greater flexibility for IPMC sensor design. These results align with predictions from the existing physics-based chemoelectromechanical model.  more » « less
Award ID(s):
1809852
NSF-PAR ID:
10344332
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Electroactive Polymer Actuators and Devices (EAPAD) XXIV
Volume:
PC12042
Page Range / eLocation ID:
PC120420L
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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