When voltage is applied to the dielectric elastomer actuator (DEA), the electrodes coated on both sides of the soft material are stretched and deformed (the surface area of the electrode part seems to increase or decrease as it looks).
Video
Materials
- Elastomer sheet (Acrylic elastomer, VHB4910J by 3M)
- Stencil sheet (PET with release treatment of silicon, design is explained in the instruction)
- Carbon powder (Black Pearl 2000 by Cabot)
- Ring Frame (POM, inner diameter : 80mm, outer diameter : 100mm, thickness : 10mm)
- Guide paper (The diameter of the circle is 26.6mm)
- Aluminium tape
- Gloves
Tools and Equipments
- High voltage power (~5.5kV)
- Pen
- Cutter
- Brush
- Spatula
Directions
Draw the guide line
Cut the elastomer sheet in the size of 80mm x 80mm. Place the sheet on the guide paper with the sticky side facing up. Draw the guide line on the elastomer sheet. The diameter of the circle is 26.6mm.
Stretch
Peel off the film from the elastomer sheet. Put the sheet on the acrylic frame and stretch it little by little. This process adds triaxial strain, which has the effect of thinning the film’s thickness, constraining the direction of movement, improving the withstand voltage, and controlling rigidity.
Stretch even more
Stretch the elastomer sheet until the guide line meets the acrylic frame.
Cut off
Cut the excess elastomer sheet off. The frame is done!
Stencil sheet
Place the stencil sheet on the center of the frame. The diameter of the circle is 30mm and the width of the wiring part is 5mm.
Design of the Stencil Sheet
Carbon Powder
Put a single dose of carbon powder on the elastomer sheet with a spatula. Spread it on the sheet as thin and as even as possible with a brush.
Take off
Discard the excess powder and remove the stencil sheet.
The opposite side
Place the other acrylic frame on top. Turn it over to make another electrode on the opposite side. Do the same process from “Stencil sheet”. But the electrode should be rotated 90 degrees.
Wiring
Cut the aluminum tape in the width of the electrode’s wiring part. Attach the tape to the wiring parts on each side of the elastomer sheet. Fold the excess tape.
Connect power
Connect the electrodes to a high voltage power supply. For safety, ensure that the negative electrode is on the top. (The positive electrode is dangerous!). The voltage should be around 0~5.5kV.
Basic Principles
DEA (Dielectric elastomer actuator) changes its size, shape and volume based on the electric field. DEA consists of a thin elastomeric film (this time we used an acrylic elastomer sheet), sandwiched between two compliant electrodes. When a strong current flows, the soft elastomer film stretches due to the electrodes pulling it from both sides.
More Informations
- Instructor in video : Satoshi Nakamaru
Additional research (Recommended by the instructor)
- Research paper : High-speed electrically actuated elastomers with strain greater than 100%
- Research paper : Flexible and Stretchable Electrodes for Dielectric Elastomer Actuators
- Research video : Primitive / Bending Type
- Research center : EPFL
- Art Work : Elastomeric Escapisms