Shape-transformable switch apparatus based on electrorheological fluid

1. A shape-transformable switch apparatus comprising:

a housing comprising:

an accommodating region with a high voltage electrode accommodating an Electrorheological (ER) fluid;

a first filling portion in contact with the high voltage electrode and filled with the ER fluid, wherein the ER fluid is configured to change viscosity and rigidity; and

a second filling portion;

a switch cover shielding an upper portion of the housing, the switch cover configured to change a shape based on changes of the viscosity and of the rigidity of the ER fluid; and

a controller configured to allow a voltage to be applied to the high voltage electrode for generating an electrostatic attraction so that the ER fluid is deformed thereby changing the shape of the switch cover,

wherein the second filling portion forms a step with the first filling portion, protruding from the first filling portion and connecting to a center portion of the switch cover, and

wherein the second filling portion is filled with the ER fluid.

2. The apparatus of claim 1 , wherein the housing further comprises:

a ground electrode configured to change its shape by the electrostatic attraction when the voltage is applied to the high voltage electrode, and

a thin-film member configured to change its shape together with the ground electrode when the shape of the ground electrode is changed, the thin-film member being configured to press against the ER fluid in the first filling portion.

3. The apparatus of claim 1 , wherein a width of the first filling portion is larger than a width of the second filling portion.

4. The apparatus of claim 2 , wherein the thin-film member is arranged on opposite sides of the protrusion of the second filling portion at the first filling portion together with the ground electrode, and wherein the thin-film member is configured to press the ER fluid filled in the first filling portion when the electrostatic attraction is generated thereby allowing the ER fluid to flow to the second filling portion.

5. The apparatus of claim 1 , wherein the switch cover comprises a soft material.

6. The apparatus of claim 1 , wherein the switch cover is formed in a flat shape, and is configured such that a shape of the center portion of the switch cover is changed to protrude by the ER fluid that flows from the first filling portion to the second filling portion.

7. The apparatus of claim 1 , further comprising a sensor disposed inside the housing, wherein the sensor is configured to sense a contact state by using a change in capacitance that is changed according to an approach distance of an object.

8. The apparatus of claim 7 , wherein the sensor comprises a carbon electrode layer and is attached to an inner side of the switch cover.

9. The apparatus of claim 7 , wherein the controller is configured to control the voltage based on an input of the sensor such that the voltage is applied to the high voltage electrode when a capacitance increases.

10. The apparatus of claim 1 , wherein, in a state in which the shape of the switch cover is changed, the controller is configured to control the voltage such that the voltage applied is turned off when it is determined that a pressure is applied to the switch cover, thereby allowing the shape of the switch cover to return to an initial shape.

11. The apparatus of claim 1 , wherein the ER fluid is deformed based on changes to a magnetic field.