It is the light and soft polymer actuator developed for the first time in the world. This actuator forms the electrode by special chemical plating, and improves the displacement performance greatly by enlarging the surface area of the electrode. This is composite materials of the polymer and the metal. It moves quickly and greatly by the low voltage of about 2V.
Photograph in cross-section of actuator.
The electrode of actuator has fractal-like structure.
   1. A motion is electrically controllable.
   2. It is softness about the same as muscles.
   3. Since it almost consists of polymer, it is light.
   4. It is completely silent when driving.
   5. Generating power becomes large by enlarging size.
   6. A thin device can be made by using the actuator from 0.1 to 10mm.
   7. Movement like the living thing is obtained by combining the actuator elements.
   8. It is possible to move with low electric power (about 0.05 to 0.2W).
   9. It can be worked for a long term (one year).
  10. It works in water or air.
  11. The electromotive force is generated while depending on the deformation of the actuator.

It has many excellent characteristic that is nothing on the conventional motor.A new innovative device can be designed.

1.Basic operating characteristic

The element is made of ion-exchange polymer, and is the hardness about muscles of a living body. Since it is soft, generating power greatly depend on the sizes and structures of actuator. Response frequency also depend on prudence and length.

ribbon sahpe
(mm) 0.2t×1×20 0.2t×1×5 0.5t×3×10 1t×3×10
Response frequency(Hz) 50 500 30 20
Displacement(mm) Three rotations rotations rotations 1/2 rotations
Speed(mm/sec) 50 100 30 20
Generating power(g) 0.02 1.0 6.0 40

donuts shape
(mm) 0.5t×10φ 0.5t×30φ
Response frequency(Hz) 30 30
Displacement(mm) 0.5 0.5
Speed(mm/sec) 0.5 1
Generating power(g) 20 70

2.Working Principle

The mechanism of the bending motion
is due to uni-directional electro-osmosis by cation,
with their polar solvent, toward the cathode. Solvent
enrichment at the cathode and depletion at the anode
cause bending due to differential swelling and shrinkage.

3.Design for Actuator

Ion conductive actuator does various operation depending on the following condition.
  • Actuator size
    Generating power becomes large by enlarging thickness.(Figure of thickness vs power)
    A motion changes with the shape cutting from the film and the shape of a casting.
    (Figure of element length vs power)
  • Actuator shape
    The generation power depends on the rigidity of the actuator and the position of the fulcrum.
    Large power is generated if there are a lot of fulcrums. A tube actuator enables bending of all directions.
  • Ditch for electric insulation
    A curved direction can be controlled by making the insulation ditch. Moreover,
    because the resistance of each insulated actuator changes by making the
    insulation ditch, various movements can be made.
  • Two or more connections
    It moves in the counter direction respectively.
  • The kind of ion
    Because the displacement rate and the amount of displacement depend on the
    kind of the ion, it is possible to select it by the usage.
  • Control of operation
    The displacement, the displacement rate, and the position can be
    controlled by a low electric power.
  • The waveform of applying voltage
    The displacement rate can be controlled even by one cycle or less.
    Movement near the living thing is possible.
  • Position of lead terminal supplying electricity
    The voltage depends on the distance from the terminal because the actuator has a
    little electric resistance. Therefore, because displacement depends on the >
    distance from the terminal, movement can be controlled by the position of
    the terminal.

    4.Basic operation of an actuator(in air)

    Type of 2 direction
    The generation power grows in proportion to the cube
    though displacement and the displacement speed of the actuator
    are in inverse proportion to thickness.
    高分子アクチュエータの動作 高分子アクチュエータの­生力 高分子アクチュエータの­生力 高分子アクチュエータの­生力
    0.2mm thickness 1mm thickness 3mm thickness 5mm thickness

    Type of 4 direction
    The actuator point can be moved in a free all directions by
    arranging the electrode on four sides of the quadratic prism,
    and applying the voltage to the opposed electrodes respectively.
    マイクロマシン 内視鏡
    Type of Hign speed Type of large displacement

    Type of hign power
    High generating power can be demonstrated also with
    by optimizing the shape and the direction of operation.
    レンズ駆動 レンズ駆動
    Donuts shape C shape

    5.Biomimetic motion(under water or in air)

    ヘビ模擬運動 Snake

    The model consist of four-segment ribbon, connected in
    reverse polarity. It moves just like a snake.
    クラゲ模擬運動 Jellyfish

    The model is a single piece with eight-arms free to move
    in the same direction.This is an easy structure, and it
    moves like jellyfish by applying the voltage to upper and
    lower sides.
    面アクチュエータ Control of a curved surface

    Complex movement is possible by the idea of the electric
    insulation ditch on the surface of a film actuator and the
    pattern of the applying voltage. Left animation is a film actuator with 3cm by 3cm.
    人工目玉 Artificial eye

    The eyeball and the eyelid of the living body can move
    exactly according to the idea of shape and cutting.


    It can be held by moving each finger. Since the actuator is soft to the real muscles, excess power is not added.
    ロボットハンド(開) ロボットハンド(閉) ロボットハンド(グー) ロボットハンド(チョキ)

    ロボットハンド開閉動作(動画) ロボットハンド物体把持動作(動画) ロボットハンド物体移動動作(動画)
    Opening-and-closing operation Object holding Object moving

     The specification that moves complexly in all directions is also possible
      though the actuator of animation above is two direction specification.

    ※Those who wish to develop jointly  Please inform web@eamex.co.jp.
    By various demonstrations and the sample, I explain details.

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