The EAP-in-Action Session and Demonstration is part of the Electroactive Polymer Actuators and Devices (EAPAD) XXVI conference.

Session Chair:

Iain Anderson The Univ. of Auckland (New Zealand)

This session highlights some of the latest capabilities and applications of Electroactive Polymers (EAP) materials where the attendees are shown demonstrations of these materials in action. Attendees interact directly with technology developers and are given a "hands-on" experience with this emerging technology. The first Human/EAP-Robot Arm Wrestling Contest was held during this session of the 2005 EAPAD conference.

 

EAP Demonstrations:

Commercializing multi-channel high voltage amplifiers for electroactive polymers

Shane Mitchell, Artimus Robotics (United States)




High voltage electronics products from Artimus Robotics feature high voltage amplifiers with integrated high voltage power supplies. These specialized high voltage amplifiers are turnkey, multi-channel devices designed specifically for electrostatic applications. Each device can feature up to 8 independent output channels, each with an integrated control module for near-arbitrary output voltage waveforms (linearly or nonlinearly from 0-100%). Additional features include voltage monitors on each channel, portable power sources (battery), and an application programming interface (API) using serial communication. Current efforts are focused on productization and cost reduction of these products and the development of new features such as bipolar outputs (+/- voltages) and capacitive sensing. This demonstration will highlight the capabilities of these power supplies to drive arrays of HASEL electroactive polymer actuators from Artimus Robotics. However, the capabilities afforded by these devices are applicable to a wide range of electrostatic devices and applications.

Environmental engines using twisted and coiled polymer fibers

Burhan Abbasi, Zhen Jiang, and Geoffrey Spinks, Univ. of Wollongong (Australia)




Environmental engines operate by utilizing freely available energy sources to produce mechanical motion. In this demonstration, we will show continuously rotating engines that are powered by the contraction and expansion of twisted and coiled polymer fiber artificial muscles. The first working prototype uses heat to contract the muscles and ambient cooling for the reverse expansion stroke. The engine is designed to sequentially move the muscle through heating and cooling zones so that continuous motion is produced. The mechanical work and power output of the engine will be demonstrated by lifting weights attached to the engine's drive shaft. Material properties and engine designs that affect the power output will be demonstrated.

Haptic devices for refreshable and dynamic tactile information communication

Qibing Pei, Hyeon Ji Hong, Yuxuan Guo, Kede Liu, Yang Luo, and Ziqing Han, Univ. of California, Los Angeles (United States)


Figure 1: (left) A refreshable Braille display based on a variable stiffness polymer and (right) a haptic device based on high-performance dielectric elastomer stack.

Soft Materials Research Laboratory has developed two distinctive electroactive polymers for haptic applications: a multi-line Braille display (Figure 1A) and a haptic device (Figure 1B). The bistable electroactive polymer is stiff at ambient temperature, but highly compliant and stretchable with consistent resistance above its transition temperature (~40 ºC). This enables localized electrode heating to selectively activate specific Braille cells to depict Braille characters. A functional prototype Braille device will be demonstrated. Meanwhile, the processable, high-performance dielectric elastomer is capable of dynamic, large-strain actuation. We will also showcase a haptic device based on stacked dielectric elastomer films, capable of generating various haptic force patterns.

Resonance-optimized dielectric elastomer pump demonstrator

Matthias Baltes, ZeMA gGmbH (Germany), Daniel Bruch, Univ. des Saarlandes (Germany), Paul Motzki, ZeMA gGmbH and Univ. des Saarlandes (Germany), and Stefan Seelecke, ZeMA gGmbH and Univ. des Saarlandes (Germany)




This demonstrator serves as a functional prototype designed to address performance challenges encountered with dielectric-based pumps. The primary objective of this demonstrator is to illustrate our capability to align the mechanical resonance frequency with our designated working frequency to suit specific load requirements. By tailoring various elements, including the pump chamber, pump membrane geometry, basing mechanism, and dielectric elastomer configuration, the pump achieves a resonance-optimized system.

Furthermore, we demonstrate the capability to adapt our electrical input in such a way that the system remains at a resonance-optimized working point, even when encountering different loads. This adaptive feature allows the demonstrator to consistently deliver peak performance across a range of specific load requirements.

This achievement is made possible by the benefits of dielectric elastomers (DEs), including their high-frequency operation, flexibility in design, scalability, and more. By showcasing this adaptability, our demonstrator shows an approach for overcoming existing limitations in dielectric elastomer technology in the field of pump applications, presenting a pathway toward more efficient and versatile pump systems.

Tactile Fingertips™ and Synthetic Muscle™ in robotics for human-like grip

Lenore Rasmussen, Calum Briggs, Yanni Sporidis, and Peter Vicars, Ras Labs, Inc. (United States)


EAP Sensing: Human-like grip, feedback, & dexterous control in robots – from apples to raspberries – and everything in between.

Ras Labs makes Tactile Fingertips™, which are remarkably like human fingertips, but are more sensitive and robust (20,000,000+ cycles) with 25X faster response times. Tactile Fingertips are based on Synthetic Muscle™, which is a class of electroactive polymers (EAPs) that sense pressure (gentle pressure to high impact), contract and expand at low voltage, and attenuate force. Tactile Fingertips™ touch sensors will be demonstrated gently handling a variety of objects using both electric and pneumatic robotic grippers.

Synthetic Muscle was retrofitted into a small linear actuator. A human with their finger can push against the plunger that is in connection with the EAP system in its expanded state inside a porous tube within the actuator. Of interest is that when the electricity is stopped (0 V), the EAP continues to shape-morph in the direction of its last mode (either contraction or expansion).

TouchDetect: Tactile sensation for industrial robotic grippers, enabled by soft elastomers

Artem Prokopchuk, Institute for Semiconductors and Microsystems, TU Dresden (Germany)


Figure 1: A robotic gripper gets its touch sensitive feedback from TouchDetect

PowerON’s first product is a flexible skin called "TouchDetect", which gives robotic grippers fingertip sensitivity (Figure 1). It registers how objects are gripped, preventing slipping, twisting and damage. This sensitivity enables automation of processes that were previously only possible manually. These include, for example, the handling of soft, bendable rubber objects or textile products, glassware, food and much more.

TouchDetect consists of a variable number of touch-sensitive pixels (taxels). The skin is composed of silicone and conductive inks made of different kinds of carbon. It comes with hard-ware-enabled anti-ghosting. Ghosting is a parasitic signal/effect appearing in passive sensor/resistor networks, sometimes also misunderstood as electrical crosstalk. We will demonstrate its capabilities and introduce the TouchDetect Development Kit.

Towards artificial muscles using PDMS thin fiber actuators

Magdalena Skowyra, Christopher Daniel Woolridge, Zhaoqing Kang, Florina-Elena Comanici, Liyun Yu, and Anne Ladegaard Skov, Danish Polymer Ctr., Technical Univ. of Denmark (Denmark)


Figure 1. PDMS thin fiber actuator: (a) a muscle fiber diagram, (b) PDMS hollow fiber bundle, (c) PDMS single fiber before and (d) after manual stretching. Copyrights: www.highnorth.co.uk/articles/skeletal-muscles-cycling.

The fibular properties of natural muscles are mimicked using thin polydimethylsiloxane (PDMS) fiber actuators providing stable linear strains up to 9% at 50V/µm in both wet and dry conditions. Silicone hollow fibers are produced using a wet spinning technique through a photocurable thiol-ene reaction, enabling homogenous long fibers of external diameter of ~500 µm and a uniform wall thickness of ~80 µm. Fiber actuators are prepared using ionic liquid as an inner electrode and ionogel or ionic liquid as an outer electrode, in a dry or wet state, respectively. A single fiber can hold up to 200 times its weight and its dimensions and properties are tunable by changing the stoichiometry, UV illumination time, and flow rate. During the demonstration session, the fiber actuator will be shown to work both in dry and wet states, consequently stretching and lifting an object, demonstrating the strength and application possibilities of the device.

---

Event Details

FORMAT: 5–10-minute presentations followed by live demonstrations and casual Q&A.
SETUP: Room for standing to view demos and theater style seating.

.