Haptic Actuator Using Magnetorheological Elastomer and Magnetorheological Fluid

Abstract

To provide a haptic actuator using a magnetorheological elastomer and a magnetorheological fluid. [Solution] The magnetorheological elastomer surrounds an iron elastomer and a magnetorheological fluid, and the increased stiffness of the magnetorheological elastomer and the increased viscosity of the magnetorheological fluid can provide kinesthetic feedback in response to an external force. When an alternating magnetic field is applied, the shape is repeatedly compressed and restored to generate vibrations, providing vibration feedback.

Description

[Technical field]

[0001] The present invention relates to a haptic actuator using a magnetorheological elastomer and a magnetorheological fluid, and more specifically, to a haptic actuator using a magnetorheological elastomer and a magnetorheological fluid, which has a configuration in which a magnetorheological elastomer surrounds an iron elastomer and a magnetorheological fluid, and which can provide kinesthetic feedback in response to an external force by increasing the rigidity of the magnetorheological elastomer and the viscosity of the magnetorheological fluid, and which can provide vibration feedback by repeatedly compressing and restoring its shape when an alternating magnetic field is applied, thereby generating vibrations. [Background technology]

[0002] In general, magnetorheological fluids (MR fluids) are fluids that have the effect of increasing the flow resistance of the fluid when a magnetic field is applied, and exhibit a phenomenon similar to the ER effect. Magnetorheological fluids are fluids in which paramagnetic particles are dispersed in a solvent with low permeability, and when there is no magnetic field applied, they behave like a Newtonian fluid in which the particles move freely, but when there is a magnetic field applied, the particles become charged and form a chain structure, exhibiting the behavior of a Bingham fluid with yield stress.

[0003] Such magnetorheological fluids are used in the design, manufacture, positioning, and vibration control of a variety of application devices, such as shock absorbers, impact dampers, engine mounts, and car suspensions.

[0004] Meanwhile, currently developed MR dampers are very expensive and large in volume, so they are mainly used in the fields of automobiles, railways, and civil engineering / construction. In order to use them in haptic footwear or VR controller buttons, the volume and weight must be reduced, and there is a need to significantly reduce production costs compared to current levels to increase price competitiveness. This means that technological development to satisfy this requirement is currently required. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Korean Patent No. 10-2311171 Summary of the Invention [Problem to be solved by the invention]

[0006] In order to solve the above problems, the present invention aims to provide a haptic actuator using a magnetorheological elastomer and a magnetorheological fluid, which has a configuration in which an iron elastomer and a magnetorheological fluid are surrounded by a magnetorheological elastomer, and which can provide kinesthetic feedback in response to an external force by increasing the rigidity of the magnetorheological elastomer and the viscosity of the magnetorheological fluid, and which can provide vibration feedback by repeatedly compressing and restoring its shape when an alternating magnetic field is applied, thereby generating vibrations. [Means for solving the problem]

[0007] A haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to one embodiment of the present invention includes a magnetorheological elastomer housing 110 having a hollow portion 111 formed therein, an elastomer 120 provided within the magnetorheological elastomer housing 110, and a magnetorheological fluid 130 filled in the hollow portion 111. When an external magnetic field is applied, the rigidity of the magnetorheological elastomer housing 110 is increased and the viscosity of the magnetorheological fluid 130 is increased, thereby increasing resistance to external forces. When an external alternating magnetic field is applied, the magnetorheological elastomer housing 110 repeatedly compresses and restores in the direction of the external magnetic field, thereby generating vibrations.

[0008] In one embodiment, the magnetorheological elastomer housing 110 may correspond to a cylindrical shape with a hollow interior.

[0009] In one embodiment, the magnetorheological elastomer housing 110 may be hollow and formed to have a size corresponding to the area of ​​the sole of the footwear.

[0010] In one embodiment, a plurality of elastomers 120 may be provided in the inner hollow portion 110 of the magnetorheological elastomer housing 110 having a size corresponding to the area of ​​the sole of the footwear.

[0011] In one embodiment, when a magnetic field is generated locally from a specific external magnetic field generating device among a plurality of external magnetic field generating devices installed in the entire sole area of ​​the footwear, the stiffness and viscosity of the magnetorheological elastomer housing 110 and the magnetorheological fluid 130 in an area adjacent to the area where the magnetic field is generated can be locally increased.

[0012] In one embodiment, the magnetorheological elastomer housing 110 may be provided in a plurality of units corresponding to the area of ​​the sole of the footwear.

[0013] In one embodiment, the elastomer 120 may have upper and lower sides contacting the interior upper and lower surfaces of the magnetorheological elastomer housing 110, respectively.

[0014] In one embodiment, upon application of an external magnetic field, iron particles within the magnetorheological fluid 130 may become vertically aligned between the elastomer 120 , disrupting compression of the elastomer 120 .

[0015] In one embodiment, when an external AC magnetic field is applied, a portion of the magnetorheological elastomer housing 110 is compressed in the direction of application of the external AC magnetic field, and when the direction of application of the external AC magnetic field is changed, the shape of the magnetorheological elastomer housing 110 is restored to its original shape due to the elastic force of the elastomer 120, and this process may be repeated.

[0016] In one embodiment, when an external force is applied from the top to the bottom in the absence of an external magnetic field, the magnetorheological elastomer housing 110 may be compressed downward, decreasing in height and deforming so that the sides extend outward. Effect of the Invention

[0017] According to one aspect of the present invention, the increased stiffness of the magnetorheological elastomer and the increased viscosity of the magnetorheological fluid can provide kinesthetic feedback in response to an external force, and has the advantage that vibration feedback can be provided by repeatedly compressing and restoring the shape upon application of an alternating magnetic field, generating vibrations.

[0018] In addition, according to one aspect of the present invention, the simplified and compact structure allows application to areas requiring ultra-small volume applications such as tactile footwear and VR controllers, thereby offering the advantage of significantly reducing production costs and improving price competitiveness. [Brief description of the drawings]

[0019] [Figure 1] 1 is a diagram showing a configuration of a haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to an embodiment of the present invention. [Diagram 2] 1 is a diagram illustrating a concept in which resistance is increased when a magnetic field is applied to a magnetorheological elastomer housing 110. FIG. [Diagram 3] 1 is a diagram showing a state in which the shape of a magnetorheological elastomer housing 110 is deformed by application of an external magnetic field. [Figure 4] 1 is a diagram showing a state in which vibration of a magnetorheological elastomer housing 110 is generated by application of an external AC magnetic field. [Diagram 5] 1 is a diagram showing an embodiment in which a haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to the present invention is applied to an actuator including a coil and a ferromagnetic housing. [Figure 6]1 is a diagram showing an embodiment in which a haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to the present invention is applied to a button of a VR controller. [Figure 7] 1 is a diagram showing an embodiment in which a haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to the present invention is applied to a tactile shoe sole. [Figure 8] 1. This is a diagram showing an embodiment in which an electro-rheological elastomer housing is applied instead of the magnetorheological elastomer housing 110 shown in FIG. 1, and an electro-rheological fluid is applied instead of the magnetorheological fluid 130. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] In the following, preferred embodiments are presented to facilitate understanding of the present invention. However, the following embodiments are provided only to facilitate understanding of the present invention, and the contents of the present invention are not limited to the embodiments.

[0021] FIG. 1 is a diagram showing the configuration of a haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to one embodiment of the present invention, and FIG. 2 is a diagram showing the concept of increasing resistance force when a magnetic field is applied to a magnetorheological elastomer housing 110.

[0022] 1 and 2, a haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to an embodiment of the present invention is broadly composed of a magnetorheological elastomer housing 110, an elastomer 120, and a magnetorheological fluid .

[0023] First, the magnetorheological elastomer housing 110 has a hollow portion 111 formed therein, and the elastomer 120 and the magnetorheological fluid 130 are accommodated in the hollow portion 111. More specifically, the hollow portion 111 forms a space sufficient to accommodate the elastomer 120 and the magnetorheological fluid 130. In this case, even if the shape of the magnetorheological elastomer housing 110 is deformed by being pressed or crushed by an external force, the magnetorheological elastomer housing 110 itself surrounds the elastomer 120 and the magnetorheological fluid 130, so that the magnetorheological fluid 130 can be prevented from leaking out.

[0024] Such magnetorheological elastomer 110 may basically have a hollow cylindrical shape. In one embodiment, the magnetorheological elastomer 110 may be formed in a shape similar to the shape of the sole of the tactile footwear, and may be formed to have a size corresponding to the area of ​​the sole of the footwear.

[0025] Elastomer 120 is provided in the vertical direction inside magnetorheological elastomer 110, and basically, one elastomer is provided, but the number and arrangement of elastomer 120 can be changed as much as you want depending on the shape and size of magnetorheological elastomer 110.

[0026] When an external magnetic field or an external AC magnetic field is applied to the magnetorheological elastomer 110, its shape can be deformed depending on the direction of the applied magnetic field, which will be described later.

[0027] The elastomer 120 is provided in the magnetorheological elastomer housing 110 and is arranged to face the up-down direction. The elastomer 120 is mainly made of steel (iron), and the upper and lower sides of the elastomer 120 are provided so as to contact the inner upper and lower sides of the magnetorheological elastomer housing 110, respectively.

[0028] Because the elastomer 120 has its own elasticity, when a physical external force is applied to the upper or lower side, or when an external magnetic field is applied to the magnetorheological elastomer housing 110, the shape of the magnetorheological elastomer housing 110 is deformed, the elastomer 120 can be compressed accordingly.

[0029] When the elastomer 120 is compressed, the elastomer 120 maintains its elasticity independently, so that when the object applying the external force disappears or the external magnetic field applied to the magnetorheological elastomer housing 110 disappears, the elastomer 120 returns to its original state, and the magnetorheological elastomer housing 110 can also return to its original shape.

[0030] In addition, the remaining area of ​​the hollow portion 111 of the magnetorheological elastomer housing 110, except for the elastomer 120, is filled with the magnetorheological fluid 130. Therefore, when the viscosity of the magnetorheological fluid 130 is increased by an external magnetic field, the elastomer 120 is not compressed because the iron particles constituting the magnetorheological fluid 130 are aligned vertically between the elastomer 120, and the resistance force can be structurally increased, as will be described later.

[0031] The magnetorheological fluid 130 is filled in the hollow portion 111 so as to fill the remaining area except for the elastomer 120, and when an external magnetic field is applied, the viscosity of the magnetorheological fluid 130 increases, thereby hindering the compression of the elastomer 120. When the external magnetic field is removed in this state, the viscosity of the magnetorheological fluid 130 returns to its original viscosity, and in this case, the elastomer 120 can be compressed again as usual.

[0032] Next, a more detailed description will be given of a state in which the magnetorheological elastomer housing 110 and the magnetorheological fluid 130 are deformed by an external magnetic field or an external AC magnetic field, and are repeatedly compressed and restored in the direction of the applied magnetic field, thereby generating vibration.

[0033] FIG. 3 is a diagram showing the state in which the shape of the magnetorheological elastomer housing 110 is deformed by the application of an external magnetic field, and FIG. 4 is a diagram showing the state in which vibration of the magnetorheological elastomer housing 110 is generated by the application of an external alternating magnetic field.

[0034] First, referring to FIG. 3, when an external magnetic field is applied outside the magnetorheological elastomer housing 110, the rigidity of the magnetorheological elastomer housing 110 increases due to the external magnetic field, and the structural resistance to external forces increases, thereby suppressing deformation of the shape.

[0035] At the same time, the viscosity of the magnetorheological fluid 130 filled in the magnetorheological elastomer housing 110 increases. Since the iron particles in the magnetorheological fluid 130 are aligned vertically between the elastomer 120, the elastomer 120 is not compressed, and the structural resistance is further increased, so that deformation can be further suppressed.

[0036] Such points may be applied to buttons (e.g., buttons on a VR controller) that potentially limit externally applied pressure, or may be applied to the soles of shoes worn by the user to provide a variety of kinesthetic feedback.

[0037] 4, when an external AC magnetic field is applied to the outside of the magnetorheological elastomer housing 110, the shape of the magnetorheological elastomer housing 110 is deformed in the direction of the external AC magnetic field. At this time, the inner elastomer 120 is compressed accordingly, but when the direction of the external AC magnetic field is reversed, the shape of the magnetorheological elastomer housing 110 is restored to its original state by the restoring force of the elastomer 120. When this process is repeated, vibrations can be generated in the magnetorheological elastomer housing 110. This point can be applied to a button (e.g., a button of a VR controller) that may limit the pressure applied from the outside to generate vibrations, or can be applied to the sole of a shoe worn by a user to provide vibration feedback in response to a stepping action.

[0038] Below, we will explain examples in which the haptic actuator 100 using such a magnetorheological elastomer and magnetorheological fluid is applied to various areas such as an actuator consisting of a coil and a ferromagnetic housing, buttons on a VR controller, and the soles of haptic footwear.

[0039] FIG. 5 is a diagram showing an embodiment in which a haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to the present invention is applied to an actuator consisting of a coil and a ferromagnetic housing, FIG. 6 is a diagram showing an embodiment in which a haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to the present invention is applied to a button of a VR controller, and FIG. 7 is a diagram showing an embodiment in which a haptic actuator 100 using a magnetorheological elastomer and a magnetorheological fluid according to the present invention is applied to the sole of a tactile footwear.

[0040] Referring to FIG. 5, the haptic actuator 100 using the magnetorheological elastomer and magnetorheological fluid according to the present invention can be applied to an actuator composed of a coil and a ferromagnetic housing.

[0041] At this time, the actuator composed of the coil and the ferromagnetic housing may correspond to a button, a damper, etc., and when a magnetic field is applied, a magnetic field is formed in the entire inside of the coil and the ferromagnetic housing as shown in Fig. 5(b). At this time, the shape deformation of the magnetorheological elastomer housing 110 can be suppressed to the maximum extent due to the increase in the rigidity of the magnetorheological elastomer housing 110 and the increase in the viscosity of the magnetorheological fluid 130 in the haptic actuator 100 using the magnetorheological elastomer and the magnetorheological fluid, and therefore the resistance of the magnetorheological elastomer housing 110, the elastomer 120, and the magnetorheological fluid 130 is maximized without decreasing the height, so that a strong resistance can be applied to the actuator composed of the coil and the ferromagnetic housing.

[0042] In addition, when an external AC magnetic field is applied, the shape of the magnetorheological elastomer housing 110 is deformed in the direction of the applied external AC magnetic field by the external AC magnetic field. At this time, the inner elastomer 120 is compressed accordingly. When the direction of the applied external AC magnetic field is reversed, the shape of the magnetorheological elastomer housing 110 is restored to its original state by the restoring force of the elastomer 120. When this process is repeated, vibration can be generated in the actuator composed of a coil and a ferromagnetic housing.

[0043] 6, the haptic actuator 100 using the magnetorheological elastomer and magnetorheological fluid according to the present invention can also be applied to the buttons of a VR controller. Normally, the buttons are freely pressed, but when a magnetic field is applied, the shape deformation of the magnetorheological elastomer housing 110 is suppressed to the maximum extent due to the increase in the rigidity of the magnetorheological elastomer housing 110 and the increase in the viscosity of the magnetorheological fluid 130 in the haptic actuator 100 using the magnetorheological elastomer and magnetorheological fluid, thereby providing various user experiences that prevent the buttons from being pressed. By utilizing this, the buttons can be selectively pressed in various environments such as games and VR content.

[0044] 7, the haptic actuator 100 using the magnetorheological elastomer and magnetorheological fluid according to the present invention can also be applied to the sole of a haptic footwear. More specifically, the sole of the haptic footwear may be provided with a separate external magnetic field generating device composed of a coil, an electromagnet, an EPM, etc. A plurality of external magnetic field generating devices may be provided in the sole of the haptic footwear, and all the external magnetic field generating devices may generate a magnetic field collectively, or a specific external magnetic field generating device may generate a magnetic field locally.

[0045] In this case, a magnetorheological elastomer housing 110 having a size and area corresponding to the shape of the sole of the tactile footwear is provided under the external magnetic field generating device. A plurality of elastomers 120 may be disposed inside the magnetorheological elastomer housing 110. In this state, when a magnetic field is locally generated from a specific external magnetic field generating device, the stiffness and viscosity of the magnetorheological elastomer housing 110 and the magnetorheological fluid 130 in an area adjacent to the area where the magnetic field is generated may be locally increased.

[0046] In addition, when an external alternating magnetic field is generated by an external magnetic field generating device, vibrations can be generated from the magnetorheological elastomer housing 110 in an area adjacent to the area where the magnetic field is generated. As a result, when the haptic footwear is applied to a situation such as virtual reality, various virtual terrains can be expressed and provided to the wearer of the shoe through changes in stiffness and vibration.

[0047] Meanwhile, in the haptic actuator 100 using the magnetorheological elastomer and magnetorheological fluid according to an embodiment of the present invention, an electrorheological elastomer may be applied instead of the magnetorheological elastomer of the magnetorheological elastomer housing 110, or an electrorheological fluid may be applied instead of the magnetorheological fluid 130. This will be described as follows.

[0048] FIG. 8 illustrates an embodiment in which an electro-rheological elastomer housing is used instead of the magnetorheological elastomer housing 110 shown in FIG. 1, and an electro-rheological fluid is used instead of the magnetorheological fluid 130. In FIG.

[0049] 8, in the present invention, the magnetorheological elastomer applied to the magnetorheological elastomer housing 110 may be replaced with an electrorheological elastomer (ERE), and the magnetorheological fluid 130 may be replaced with an electrorheological fluid (ERF). In this case, the stiffness and viscosity are increased in the same manner as the magnetorheological elastomer housing 110 and the magnetorheological fluid 130 described above by applying an electric field instead of a magnetic field from the outside, and therefore it can operate like a steel body.

[0050] Although the present invention has been described with reference to preferred embodiments thereof, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention as set forth in the appended claims. [Explanation of symbols]

[0051] 100 ···Haptic Actuator Using Magnetorheological Elastomer and Magnetorheological Fluid 110 Magnetorheological elastomer housing 120 Elastomer 130 Magnetorheological fluid

Claims

1. a magnetorheological elastomer housing (110) having an internal hollow portion (111); an elastomer (120) disposed within the magnetorheological elastomer housing (110); and a magnetorheological fluid (130) filled in the hollow portion (111); Including, The elastomer (120) the upper and lower sides are configured to abut the interior upper and lower surfaces of the magnetorheological elastomer housing (110), respectively; When an external magnetic field is applied, the iron particles in the magnetorheological fluid (130) are aligned vertically between the elastomer (120) to prevent compression of the elastomer (120), and the viscosity of the magnetorheological fluid (130) increases, thereby increasing resistance to external forces. When an external AC magnetic field is applied, the magnetorheological elastomer housing (110) repeatedly compresses and restores in the direction of the external magnetic field, generating vibration; When an external AC magnetic field is applied, a portion of the magnetorheological elastomer housing (110) is compressed in the direction of the applied external AC magnetic field; When the direction of the applied external AC magnetic field is changed, the shape of the magnetorheological elastomer housing (110) is restored to its original shape by the elastic force of the elastomer (120), and this process is repeated. A haptic actuator using a magnetorheological elastomer and a magnetorheological fluid.

2. The magnetorheological elastomer housing (110) comprises: It is cylindrical with a hollow interior. A haptic actuator using the magnetorheological elastomer and magnetorheological fluid according to claim 1.

3. The magnetorheological elastomer housing (110) comprises: The inside is hollow and is formed to have a size corresponding to the sole area of ​​the footwear. A haptic actuator using the magnetorheological elastomer and magnetorheological fluid according to claim 1.

4. A plurality of the elastomers (120) are provided in the inner hollow portion (110) of the magnetorheological elastomer housing (110) having a size corresponding to the sole area of ​​the footwear. A haptic actuator using the magnetorheological elastomer and magnetorheological fluid according to claim 3.

5. When a magnetic field is locally generated from a specific external magnetic field generating device among a plurality of external magnetic field generating devices installed in the entire sole area of ​​the footwear, The stiffness and viscosity of the magnetorheological elastomer housing (110) and the magnetorheological fluid (130) in the area adjacent to the area where the magnetic field is generated are locally increased. A haptic actuator using the magnetorheological elastomer and magnetorheological fluid according to claim 4.

6. The magnetorheological elastomer housing (110) comprises: A plurality of pieces are provided corresponding to the sole area of ​​the footwear. A haptic actuator using the magnetorheological elastomer and magnetorheological fluid according to claim 1.

7. The magnetorheological elastomer housing (110) comprises: When an external force is applied from above to below without applying an external magnetic field, the shape is deformed such that the height is reduced while the surface is compressed downward and the sides are stretched outward. A haptic actuator using the magnetorheological elastomer and magnetorheological fluid according to claim 1.

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