CN211857421U - Spherical actuator for touch screen - Google Patents

Abstract

The utility model discloses a spherical actuator for a touch screen, which comprises a spherical rotor, a stator part, a spacing part and an excitation part, wherein the spherical rotor consists of a rotor ball and a magneto-rheological elastomer wrapping the rotor ball; the stator part consists of a shell, a stator ring, an upper stator sleeve and a lower stator sleeve fixedly connected with the shell, and the interval part comprises an interval ring embedded in the stator ring and an annular interval clamped between the upper stator sleeve and the lower stator sleeve; the excitation portion includes coils wound on radially outer surfaces of the stator ring and the upper stator sleeve, and the spherical rotor is movably embedded in the upper stator sleeve, the annular space, and the center of the lower stator sleeve. The actuator realizes direct interaction with the touch screen by utilizing the characteristics that the magnetorheological elastomer has electric conduction and magnetic conduction and has a large friction coefficient with the touch screen, and can provide variable lateral feedback force in a large range. The actuator has small volume and low power consumption, can obviously enhance the reality of touch screen interaction, and has wide application prospect.

Description

Spherical actuator for touch screen

Technical Field

The utility model relates to a spherical executor, more specifically relates to a spherical executor for touch-sensitive screen.

Background

In the field of haptics, friction is typically presented as a lateral force that resists finger sliding on an object surface and is perceived by the resulting lateral deformation of the skin and/or proprioception. For friction reproduction on a touch screen, there are two commonly used techniques, ultrasonic vibration and electrostatic attraction, which both provide a variable lateral force for the sliding of a bare finger on the touch screen. Although receiving a great deal of attention, both techniques simultaneously change the state of the entire touch screen when frictionally reproducing and provide the same haptic feedback effect for each contact point. Thus, these methods are primarily applicable to single finger interaction with small touch screen devices, and do not provide locally varying friction for multiple points of contact. To meet the demand for multi-finger or multi-person interaction with touch screens, some studies have utilized ball actuators to provide local lateral force feedback. Ball-based actuators have the advantage of multiple degrees of freedom of motion and can naturally perform 3 degrees of freedom of rotational motion in a single joint. Thus, the application of a ball actuator to touch screen interaction can reduce the use of gearing, thereby making the force haptic device compact and easy to miniaturize. Meanwhile, the spherical actuator has an infinite motion space in a two-dimensional plane, and can provide local force feedback for multipoint interaction. Known lateral force feedback devices based on spherical actuators control the state of motion of a ball over a surface by means of an active actuator. However, none of these devices can directly interact with the touch screen and only produce a small lateral feedback force.

Disclosure of Invention

Utility model purpose: the utility model aims at providing a spherical executor for touch-sensitive screen that possess multi freedom motion ability, can directly interact with the touch-sensitive screen to can export changeable side direction feedback force.

The technical scheme is as follows: the utility model relates to a spherical actuator for touch screen, which comprises a spherical rotor, a stator part, a spacing part and an excitation part; the spherical rotor consists of a rotor ball and a magnetorheological elastomer wrapping the rotor ball; the stator part consists of a shell, a stator ring, an upper stator sleeve and a lower stator sleeve fixedly connected with the shell; the spacing part comprises a spacing ring embedded in the stator ring and an annular spacing clamped between the upper stator sleeve and the lower stator sleeve; the excitation portion includes a coil wound on the radially outer surfaces of the stator ring and the upper stator can; the spherical rotor is movably embedded in the centers of the upper stator sleeve, the annular interval and the lower stator sleeve.

Wherein the thickness of the magnetorheological elastomer is 0.2-2 mm; an outlet hole is reserved at the top of the shell, and an outgoing line of the coil is led out through the outlet hole; the shell, the stator ring, the rotor ball, the upper stator sleeve and the lower stator sleeve form a magnetic yoke, and the magnetic yoke is made of magnetic conductive metal materials; the magnetorheological elastomer is mainly made of natural rubber and hydroxyl iron powder materials, is of an isotropic structure, has the characteristics of electric conduction and magnetic conduction, and has a large friction coefficient with the touch screen; the spacing ring and the annular spacing are made of aluminum alloy, the magnetic permeability of the aluminum alloy is low, the magnetic leakage can be reduced, and the weight of the device is reduced; the upper surfaces of the annular intervals are flush with the horizontal center line of the rotor ball, and the curved surface parts of the upper stator sleeve and the lower stator sleeve have the same surface area, so that the magnetorheological elastomers in the magnetic field activation region have the same magnetic induction intensity distribution, and an ideal force feedback effect is obtained; the spherical rotor is fixed inside the spherical actuator for the touch screen by using the plane bearing, so that the friction force generated when the spherical rotor rotates can be reduced, and the lower stator sleeve is connected to the shell through the screw.

Has the advantages that: compared with the prior art, the utility model, its advantage is: 1. the magnetorheological elastomer with the conductive and soft characteristics is used as a medium for contacting the touch screen, so that the touch screen can detect the position where interaction occurs in real time, the friction coefficient between the magnetorheological elastomer and the touch screen is remarkably increased, and the variable lateral feedback force can be provided in a larger range; 2. the used magnetorheological elastomer has magnetic conductivity, can control the lateral output force of the spherical actuator through a magnetic field induced by current, and has the characteristic of simple control method; meanwhile, because the magnetorheological elastomer is of an isotropic structure, under the excitation of a certain current level, the actuator can output a lateral force with stable magnitude in the process that the spherical rotor rotates on the touch screen; 3. the provided spherical actuator is a passive actuator, has the obvious advantages of small volume and low power consumption compared with an active actuator, better meets the requirement of multi-degree-of-freedom man-machine interaction, and can obviously enhance the reality of the interaction between a user and a virtual environment by providing multi-degree-of-freedom force/moment feedback which changes along with an interaction scene for the interaction between multiple fingers or multiple people and a touch screen.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a perspective view of the present invention;

fig. 3 is a usage state diagram of the present invention.

Detailed Description

As shown in fig. 1 and 2, the spherical actuator for the touch screen mainly comprises a spherical rotor, a stator part, a spacing part and an excitation part, and the actuator comprises a housing 1, a coil 3, a planar bearing 4, a stator ring 5, a spacing ring 6, a magnetorheological elastomer 7, a rotor ball 8, an upper stator sleeve 9, an annular space 10, a screw 11, a lower stator sleeve 12 and the like. The spherical rotor is a ball with the outer surface of a rotor ball 8 wrapped with a magnetorheological elastomer 7, and the thickness of the magnetorheological elastomer 7 is 0.2-2 mm; most of the volume of the spherical rotor is embedded inside the actuator. The magnetorheological elastomer 7 is contacted with the curved surface parts of the upper stator sleeve 9, the annular interval 10 and the lower stator sleeve 12 and the small balls in the plane bearing 4. The stator part consists of a shell 1, a stator ring 5, an upper stator sleeve 9 and a lower stator sleeve 12, wherein the upper surface of the shell 1 is provided with an outlet hole 2. The spacer portion comprises a spacer ring 6 and an annular spacer 10, the spacer ring 6 being embedded within the stator ring 5, the annular spacer 10 being sandwiched between an upper stator sleeve 9 and a lower stator sleeve 12. The excitation part comprises a coil 3 wound on the radially outer surface of the stator ring 5 and the upper stator sleeve 9, with the lead-out wires leading out through the outlet holes 2. The fixed part comprises a plane bearing 4 and a screw 11; the plane bearing 4 can not only reduce the friction force when the spherical rotor rotates, but also fix the position of the spherical rotor in the actuator; screws 11 are used to secure the housing 1 and the lower stator casing 12 together. The housing 1, the stator ring 5, the rotor ball 8, the upper stator sleeve 9 and the lower stator sleeve 12 form a magnetic yoke, which are made of a magnetically conductive metal material. The magnetorheological elastomer 7 is mainly made of natural rubber and hydroxyl iron powder materials, is of an isotropic structure, and has the characteristics of electric conduction, magnetic conduction and large friction coefficient with a touch screen. The spacer rings 6 and the annular spacers 10 are made of an aluminium alloy with a low magnetic permeability to reduce magnetic leakage and the weight of the device. The spherical actuator for the touch screen has three freedom degrees of motion and can respectively rotate, nutate and precess around an x/y/z axis of a rectangular coordinate system. The upper surface of the annular space 10 is flush with the horizontal centre line of the spherical rotor. The curved surface parts of the upper stator sleeve 9 and the lower stator sleeve 12 have the same surface area, so that the magnetorheological elastomer 7 in the magnetic field activation region has the same magnetic induction intensity distribution, and an ideal force feedback effect is obtained.

In use, as shown in fig. 3, the ball actuator is connected to the hand-held device 13 through threads on the upper portion of the housing 1 and is integrated into the lower portion of the hand-held device 13. When the hand-held device 13 is held by the user's hand and slid over the touch screen 14, the spherical rotors in the spherical actuators come into contact with the touch screen 14 and roll over the touch screen 14. Due to the fact that the magnetorheological elastomer 7 on the surface of the spherical rotor has the conductive characteristic, the touch screen 14 can detect the position where interaction occurs in real time, and then the target lateral force needing to be fed back to a user is calculated through a force touch rendering algorithm. The target lateral force signal is sent to a control circuit integrated in the handheld device 13 through Bluetooth, and the current value required to be input into the coil 3 is obtained. Because the magnetorheological elastomer 7 has the characteristic of magnetic conductivity, the magnetic field generated by electrifying the coil 3 can be transmitted in the magnet yoke and the magnetorheological elastomer 7, so that a closed magnetic circuit is formed. Under the action of the magnetic field, attraction can occur between the curved surface portions of the upper stator sleeve 9 and the lower stator sleeve 12 and the rotor ball 8, and the attraction force enables friction torque to be generated between the curved surface portions of the upper stator sleeve 9 and the lower stator sleeve 12 and the magnetorheological elastomer 7, and the friction torque is divided by the radius of the spherical rotor, namely the lateral force fed back to a user by the spherical actuator. In addition, the soft characteristic of the magnetorheological elastomer 7 can obviously increase the friction coefficient between the magnetorheological elastomer and the touch screen 14, so that the range of lateral force reproduced to a user is enlarged, and the reality sense of interaction is stronger.

Claims (9)

1. A spherical actuator for a touch screen is characterized by comprising a spherical rotor, a stator part, a spacing part and an excitation part; the spherical rotor consists of a rotor ball (8) and a magnetorheological elastomer (7) wrapping the rotor ball (8); the stator part consists of a shell (1), a stator ring (5), an upper stator sleeve (9) and a lower stator sleeve (12) fixedly connected with the shell (1), and the spacing part comprises a spacing ring (6) embedded in the stator ring (5) and an annular spacing (10) clamped between the upper stator sleeve (9) and the lower stator sleeve (12); the excitation part comprises coils (3) wound on the radial outer surfaces of the stator ring (5) and the upper stator sleeve (9), and the spherical rotor is movably embedded in the centers of the upper stator sleeve (9), the annular space (10) and the lower stator sleeve (12).

2. The spherical actuator for a touch screen according to claim 1, wherein the thickness of the magnetorheological elastomer (7) is 0.2-2 mm.

3. The spherical actuator for the touch screen according to claim 1, wherein an outlet hole (2) is formed at the top of the housing (1), and an outlet of the coil (3) is led out through the outlet hole (2).

4. Spherical actuator for touch screens according to claim 1, characterized in that the housing (1), stator ring (5), rotor ball (8), upper stator sleeve (9) and lower stator sleeve (12) constitute a magnetic yoke.

5. Spherical actuator for touch screens according to claim 1 or 4, characterized in that the housing (1), the stator ring (5), the rotor ball (8), the upper stator casing (9) and the lower stator casing (12) are made of a magnetically conductive metal material.

6. Spherical actuator for touch screens according to claim 1, characterised in that the spacer ring (6) and the annular spacer (10) are made of an aluminium alloy.

7. A ball actuator for touch screen according to claim 1, wherein the upper surface of the annular space (10) is flush with the horizontal centre line of the rotor ball (8).

8. The spherical actuator for touch screen according to claim 1, wherein the curved portions of the upper stator case (9) and the lower stator case (12) have the same surface area.

9. Spherical actuator for touch screens according to claim 1, characterized in that the spherical rotor is fixed inside the spherical actuator for touch screens with a plane bearing (4), and the lower stator casing (12) is attached to the housing (1) by means of screws (11).

Images