Electroactive Polymers Presented by Daniel Gunter, Evan Lawrence, - - PowerPoint PPT Presentation
Electroactive Polymers Presented by Daniel Gunter, Evan Lawrence, Kaylee Levine, and Zachary Miller Biological Muscles Definition of an actuator: device that converts input energy into mechanical energy Muscles as actuators
Presented by Daniel Gunter, Evan Lawrence, Kaylee Levine, and Zachary Miller
➢ Definition of an actuator: device that converts input energy into mechanical energy ➢ Muscles as actuators
○ Resilient ○ Flexible ○ Large forces ○ Sleek
➢ Muscles: a longtime subject of scientific interest
○ “Animal electricity” Luigi Galvani, 1792 ○ Role of Ca2+
➢ Biomimicry: the imitation of natural biological designs or processes ➢ 1670s: Robert Hooke ➢ Polymers
○ Lightweight, cheap, flexible ○ Response to stimuli
➢ Electroactive polymers
○ Large deformation for small input ○ 1990s: major breakthroughs
“[EAPs] will enable faster implementation of science fiction ideas into engineering reality.”
➢ Biomimetic robots ➢ Exoskeletons ➢ Unmanned aerial vehicles ➢ Space
(https://www.youtube.com/watch?v=6cdfWdHZRrE) (https://www.youtube.com/watch?v=XoyA_w0DDDc)
➢ Linear Actuators
○ Several layers of dielectric elastomer sheets wrapped around a spring. Called a spring roll ○ Voltage causes the film of sheets to squeeze in thickness while relaxing in length, causing the roll to extend. ○ Applications in prosthetics and automation.
➢ Bending Actuators
○ Electrodes are attached at various locations along circumference of Spring Roll ○ Voltage causes these locations to extend, causing the entire roll to bend away ○ Applications in steerable medical catheters
➢ Push-Pull Actuators
○ Spring Rolls configured to work against each other ○ Transferring voltage from one roll to the other can shift the position of the device back and forth ○ Similar to the opposing bicep and tricep muscles that control movement in the human arm ○ Applications in prosthetics
➢ Sensors
○ All dielectric elastomer devices experience a change in capacitance when they deflect. ○ When calibrated, this change in capacitance can be used as a sensor. ○ Can be incorporated into fabrics, fibers, strips, or coatings. ○ Application in seat belt sensors
➢ Energy Harvesting Devices
○ All dielectric elastomer devices experience a change in capacitance when they deflect. ○ This change can be manipulated through the use of electronics and produce usable electrical energy. ○ Applications for the military and other serviceman such as Policeman and Firefighters.
➢ Surface Texturing
○ Sheets of polymers are coated with patterns of electrodes with dots attached to them. ○ The electrodes are stimulated, causing the dots to be raised to varying heights. ○ Applications in “active camouflage” and improving aerodynamic characteristics of moving
Ionic Polymer Metal Composites
Chemically Plated electrodes
Carbon Nanotubes
Interactions
https://en.wikipedia.org/wiki/Ionic_polymer%E2%80%93metal_composites https://www.cambridge.org/core/services/aop-cambridge-core/content/view/090016905913EB7D9A0FB791F2B325B8/S088376940000 4590a.pdf/carbon_nanotube_electroactive_polymer_materials_opportunities_and_challenges.pdf
Ionic Polymer Gels
Alkaline
Conductive Polymer
○ P-type ○ N-type
Electrorheological Fluid
http://iopscience.iop.org.pitt.idm.oclc.org/article/10.1088/0964-1726/20/4/045006/pdf https://www.intechopen.com/books/smart-actuation-and-sensing-systems-recent-advances-and-future-challenges/simultaneous-smart- actuating-sensing-devices-based-on-conducting-polymers https://www.mdpi.com/2076-0825/4/3/135
Piezoelectric Polymers
https://www.youtube.com/watch?v=hsd7_vQqt5w
https://en.wikipedia.org/wiki/Piezoelectricity
Liquid Crystal Elastomers
Ferroelectric Polymers
https://www.sciencedirect.com/science/article/p ii/S0924424714004488 http://www.electricalbasicprojects.com/what-is-hysteresis-loss-hysteresis-loop/
➢ Lack of established fabrication processes ➢ CNT’s use are widespread and thus have more concrete methodologies ➢ Extensive Lab procedures create highly controllable results ➢ DIY low resolution EAP
○ “Fun” activity ○ Not highly controllable
➢ Prepare surface
○ Sandblasting and washing
➢ Ion Exchange via immersion in metal complex ➢ Primary Plating via immersion → layers of metal appear on surface ➢ Secondary Plating dependent on success of Primary Plating ➢ Heavily controllable process
○ Concentrations are described very specifically
Using inexpensive and dry materials
WW-EAP Fabrication Recipes. (n.d.). Retrieved from https://ndeaa.jpl.nasa.gov/nasa-nde/lommas/eap/EAP-recipe.htm Mohsen Jahanshahi and Asieh Dehghani Kiadehi (May 9th 2013). Fabrication, Purification and Characterization of Carbon Nanotubes: Arc-Discharge in Liquid Media (ADLM), Syntheses and Applications of Carbon Nanotubes and Their Composites, Satoru Suzuki, IntechOpen, DOI: 10.5772/51116. Electroactive Polymers. (n.d.). Retrieved from http://materiability.com/portfolio/electroactive-polymers-diy/ Wang, Qing Ming. (2017). Lecture 1: Introduction and Transducer Models. University of Pittsburgh. http://www.pitt.edu/~qiw4/Academic/MEMS1082/Lecture1.pdf Martonosi, Anthony N. (July 20, 2000). “Animal electricity, Ca2+ and muscle contraction. A brief history of muscle research.” Acta Biochimica Polonica, Volume 47 (No. 3), 493–516. “What is Biomimicry?” Biomimicry.org. https://biomimicry.org/what-is-biomimicry/ Brinson, Hal F., & Brinson, Catherine L. (2008). Polymer Engineering Science and Viscoelasticity: An Introduction. Retrieved from https://link.springer.com/content/pdf/10.1007%2F978-0-387-73861-1.pdf The Uses of the Future in Early Modern Europe (Eds: A. Brady, E. Butterworth), Routledge, New York 2009. Huang, Gregory T. (December 1, 2002). “Electroactive Polymers.” MIT Technology Review. https://www.technologyreview.com/s/401750/electroactive-polymers/#comments Bar-Cohen, J. (2004). Bellingham, WA: SPIE