WO2018151040A1 - Tactile sensation presenting device - Google Patents

Abstract

This tactile sensation presenting device 1 is provided with, for example, a manipulation part 2 which has a manipulation surface 200, an actuator 4 which has a piezoelectric element 40 for detecting a load applied to the manipulation surface 200 and a metal shim 41 integrated with the piezoelectric element 40, and a pushing element 5 which is provided between the manipulation part 2 and the metal shim 41 and by which deformation of the metal shim 41 increases along with a manipulation pressing down on the manipulation surface 200.

Description

Tactile presentation device Cross-reference of related applications

This application claims the priority of Japanese Patent Application No. 2017-024673 filed on Feb. 14, 2017, the entire contents of Japanese Patent Application No. 2017-024673 incorporated herein by reference. To do.

The present invention relates to a tactile sense presentation device.

A tactile transmission device comprising: an input unit; a plurality of vibration units provided in the input unit; and a control unit that vibrates a part of the plurality of vibration units according to the pressed input position. It is known (for example, refer to Patent Document 1).

This tactile sensation transmission device uses a piezoelectric element as a vibration part, and is configured to detect a load applied to the input part by the piezoelectric element.

JP 2011-90615 A

Among such tactile transmission devices, for example, there is a device in which a load is directly applied to the piezoelectric element by a pusher provided in the input unit, and an unexpected excessive load is applied to the input unit. The piezoelectric element may be damaged.

An object of the present invention is to provide a tactile sensation presentation apparatus that can suppress the breakage of a piezoelectric element when an unexpected load is applied.

A tactile sense presentation device according to an embodiment of the present invention includes an operation unit having an operation surface, a piezoelectric element that detects a load applied to the operation surface, an actuator having a metal shim integrated with the piezoelectric element, and an operation surface. An operation portion in which the deformation of the metal shim due to the operation of pushing down is increased, and a pusher provided between the metal shims.

According to one embodiment of the present invention, it is possible to provide a tactile sensation providing apparatus capable of suppressing breakage of a piezoelectric element when an unexpected load is applied.

FIG. 1A is a top view showing a tactile sensation presentation apparatus according to an embodiment. 1B is a cross-sectional view of the cross section taken along line I (b) -I (b) in FIG. 1A as viewed from the direction of the arrow. FIG. 2A is an explanatory diagram illustrating an actuator of the tactile sense presentation device according to the embodiment. FIG. 2B is a side view showing the actuator according to the embodiment. FIG. 2C is a block diagram of the tactile sense presentation device according to the embodiment. FIG. 2D is an explanatory diagram illustrating a database included in the tactile sensation presentation apparatus according to the embodiment. FIG. 3 is a flowchart showing the operation of the tactile sense presentation device according to the embodiment.

(Summary of embodiment)
A tactile sense presentation device according to an embodiment includes an operation unit having an operation surface, a piezoelectric element that detects a load applied to the operation surface, an actuator having a metal shim integrated with the piezoelectric element, and a push-down operation surface It has an operation part in which the deformation of the metal shim accompanying the operation becomes large and a pusher provided between the metal shims.

In this tactile sensation presentation device, since the operation unit and the piezoelectric element do not contact each other, the piezoelectric element is applied when an unexpected load is applied, compared to the case where the operation unit or the pusher provided in the operation unit contacts the piezoelectric element. Damage to the element can be suppressed.

[Embodiment]
(Outline of the tactile presentation device 1)
1A is a top view showing a tactile sensation presentation apparatus according to an embodiment, and FIG. 1B is a cross-sectional view taken along line I (b) -I (b) in FIG. . 2A is a schematic view showing an actuator of a haptic presentation device according to an embodiment, FIG. 2B is a side view showing the actuator, FIG. 2C is a block diagram of the haptic presentation device, and FIG. It is explanatory drawing which shows the database which a tactile sense presentation apparatus has. Note that, in each drawing according to the embodiment described below, the ratio between figures may be different from the actual ratio. In FIG. 2C, main signals and information flows are indicated by arrows.

The tactile sense presentation device 1 is arranged, for example, on the steering of a vehicle, and is configured to operate an electronic device mounted on the vehicle. The tactile sense presentation device 1 is a small operation device that is operated by an operation finger such as a thumb while holding a steering wheel. In addition, arrangement | positioning of the tactile sense presentation apparatus 1 is not limited to this, For example, you may arrange | position near the display part of the said electronic device, etc. as an operation part of an electronic device.

For example, as shown in FIGS. 1A to 2C, the tactile sense presentation device 1 includes an operation unit 2 having an operation surface 200, a piezoelectric element 40 that detects a load applied to the operation surface 200, and an integrated body with the piezoelectric element 40. The actuator 4 having the metal shim 41, and the pusher 5 provided between the metal shim 41 and the operation unit 2 that greatly deforms the metal shim 41 when the operation surface 200 is pushed down. ing. The actuator 4 is configured to detect a load and add vibration to the operation surface 200.

For example, as shown in FIG. 2A, the piezoelectric element 40 has a symmetrical shape with the pusher 5 as the center. The piezoelectric element 40 has a through hole 405. The pusher 5 is inserted into the through hole 405 and deforms the piezoelectric element 40 via the metal shim 41 in accordance with an operation of pushing down the operation surface 200 (push operation).

The tactile sense presentation device 1 further detects the touch sensor 3 as a detection unit that detects the position of the operation finger that has touched the operation surface 200 and a reference load for each of a plurality of regions defined on the operation surface 200. load force threshold determined for each region based on the load, and a drive signal S ₃ of each region for driving the actuator 4, based on the load threshold for operation finger is detected region It drives the actuator 4 by a drive signal S ₃ corresponding to the region as well as determining the operating Te and a control unit 8 for presenting tactile feedback, the by.

Therefore, the tactile sense presentation device 1 is configured to detect a load applied to the operation unit 2 and present tactile feedback by vibration.

The operation surface 200 is, for example, the surface of the operation unit 2 shown in FIGS. 1A and 1B. For example, the operation surface 200 is defined by a central region (central region 27) and a plurality of regions (upper region 23 to right region 26) located across the central region. The definition of the area of the operation surface 200 is not limited to this, and can be arbitrarily set according to the specification of the tactile sense presentation device 1.

Here, when the tactile presentation device 1 can instruct the movement of the cursor displayed on the display device, for example, the operator moves the cursor upward by pressing the upper area 23, and moves the cursor downward by pressing the lower area 24. It is possible to move in the left direction by pushing the direction and the left region 25, and in the right direction by pushing the right region 26. For example, when the operator presses the central area 27 while selecting a desired icon or the like with the cursor, execution of the function of the selected icon is determined.

As an example, when a push operation is determined for a region, the tactile sense presenting apparatus 1 presents tactile feedback imitating a click feeling when a button is pushed. The tactile feedback is not limited to this, and may be a tactile sense indicating that an operation has been accepted.

(Configuration of operation unit 2)
The operation unit 2 includes, for example, a touch sensor 3 and a base 20. The load applied to the operation unit 2 acts on the piezoelectric element 40 via the pusher 5 and the metal shim 41. The vibration generated by the actuator 4 is transmitted to the operation unit 2 through the metal shim 41 and the pusher 5.

The touch sensor 3 is bonded to the base 20. For example, as shown in FIG. 1A, the base 20 is formed in a disk shape using a resin, and the operation surface 200 which is the surface thereof is formed with arrows and characters in the vertical and horizontal directions by printing, laser, or the like. Yes.

As a modification, for example, the base 20 is formed of a transparent resin in which a light-blocking region that blocks light and a light-transmitting region that transmits light are formed on the surface, and a substrate having a light emitting unit is disposed between the touch sensor 3 and the base 20. May be. In this case, since the light from the light emitting part is transmitted through the base 20 and emitted from the transmissive area, the transmissive area is illuminated.

As a modification, the operation unit 2 is not limited to a circular shape or a symmetric shape in a top view, and may have another shape.

(Configuration of touch sensor 3)
For example, as shown in FIG. 1B, the touch sensor 3 includes a substrate 30 and an electrode unit 31. The touch sensor 3 has a disk shape according to the shape of the operation unit 2. The substrate 30 is, for example, a rigid substrate. The electrode portion 31 of the touch sensor 3 is attached to the front surface 30a side of the substrate 30, and the presser 5 is attached to the back surface 30b side.

The touch sensor 3 is, for example, a capacitive touch sensor. The touch sensor 3 is configured to output a detection signals S ₁ to determine whether the operation to any region on the region 23 to the central region 27 defined at least on the operation surface 200 a finger is in contact ing.

The electrode unit 31 of the touch sensor 3 includes, for example, detection electrodes having shapes corresponding to the shapes of the upper region 23 to the central region 27. The touch sensor 3 is configured to output a detection signals S ₁ a signal of the electrostatic capacitance detected for each area to the control unit 8.

As a modification, the touch sensor 3 includes a plurality of drive electrodes and a plurality of detection electrodes that intersect and are insulated from the drive electrodes, and the capacitance detected by all combinations of the drive electrodes and the detection electrodes. it may be configured to output to the control unit 8 as a detection signal S _1. The control unit 8 is, for example, determines an area from coordinates the operation finger is detected in the coordinate system set on the operating face 200 on the basis of the detection signal S _1.

The upper area 23 is an area surrounded by a dotted line around an upward arrow on the paper surface of FIG. 1A. The lower region 24 is a region surrounded by a dotted line around a downward arrow. The left region 25 is a region surrounded by a dotted line around the left-pointing arrow. The right area 26 is an area surrounded by a dotted line around a right-pointing arrow. The central area 27 is an area surrounded by a dotted circle at the center of the operation unit 2. A circle surrounded by dotted lines having a wider interval than the other dotted lines indicates the outer shape of the actuator 4.

The above-mentioned pusher 5 is formed in a cylindrical shape with resin, for example, and transmits the load of the operation unit 2 to the metal shim 41 of the actuator 4.

(Configuration of actuator 4)
The actuator 4 is a unimorph type piezoelectric actuator provided with a piezoelectric element 40 and a metal shim 41 as shown in FIG. 1B, for example.

For example, as shown in FIG. 1B, the actuator 4 is attached to an attachment portion 14 formed on the support portion 10. The attachment portion 14 has a shape into which the metal shim 41 of the actuator 4 is fitted. The mounting portion 14 is formed with a recess 12 that allows the actuator 4 to bend due to the load applied to the operation surface 200 and the vibration applied to the operation surface 200. The recess 12 is formed on the bottom surface of the mounting portion 14.

When the load is applied to the metal shim 41, the pusher 5 is attached to a position where the displacement is large. In other words, the pusher 5 is attached to a position where the amplitude is large when the actuator 4 is vibrating. The position where the displacement is large is the center when the metal shim 41 has a disk shape. The position where the displacement is large may be the center, the center of gravity, or the end that is the free end depending on the shape of the metal shim 41.

The piezoelectric element 40 has, for example, a disk shape as shown in FIGS. 2A and 2B, and is configured by sandwiching a piezoelectric body 401 between a first electrode 400 and a second electrode 402. Examples of the material of the piezoelectric body 401 include lithium niobate, barium titanate, lead titanate, lead zirconate titanate (PZT), lead metaniobate, and polyvinylidene fluoride (PVDF). The piezoelectric body 401 is a stacked piezoelectric body formed by stacking films formed using these materials, for example. The piezoelectric body is configured to be polarized in the thickness direction so that the piezoelectric constant is d33, and the output is increased with respect to deformation in the thickness direction.

The piezoelectric body 401 is easily broken by deformation due to an excessive load. Therefore, in this embodiment, as shown in FIG. 1B, the pusher 5 to which the load of the operation unit 2 is transmitted is inserted into the through hole 405 so as not to directly contact the piezoelectric element 40.

The first electrode 400 is electrically connected to the control unit 8 through the metal shim 41 and the wiring. The second electrode 402 is electrically connected to the control unit 8 through a wiring.

For example, as shown in FIG. 2A, the metal shim 41 has a disk shape with a radius larger than that of the piezoelectric element 40. The metal shim 41 is formed of, for example, conductive phosphor bronze or stainless steel.

When a load is applied to the operation surface 200 of the actuator 4, a load is applied to the piezoelectric element 40 via the operation unit 2, the pusher 5 and the metal shim 41, and the piezoelectric body 401 is deformed. The piezoelectric element 40 outputs a voltage corresponding to this deformation. In addition, when a voltage is applied between the first electrode 400 and the second electrode 402, the piezoelectric body 401 is deformed according to the voltage. Actuator 4, a voltage output according to the load and output to the control unit 8 as a load signal S _2, oscillates together with the metal shim 41 is deformed in accordance with a voltage based on the driving signal S ₃ output from the control unit 8 It is configured as follows.

(Configuration of control unit 8)
The control unit 8 includes, for example, a CPU (Central Processing Unit) that performs operations and processes on acquired data according to a stored program, a RAM (Random Access Memory) that is a semiconductor memory, a ROM (Read Only Memory), and the like. Microcomputer. In the ROM, for example, a program for operating the control unit 8 and a database 80 are stored. For example, the RAM is used as a storage area for temporarily storing calculation results and the like. The control unit 8 has a means for generating a clock signal therein, and operates based on the clock signal.

The control unit 8 is configured to convert the load the load signals S ₂ output from the actuator 4.

Database 80, for example, as shown in FIG. 2D, a load threshold and the driving waveform of each area, and a touch threshold Th _10.

The load threshold Th ₁ to the load threshold Th ₅ are thresholds determined based on the load detected by the actuator 4 as a result of adding a reference load for each region. Specifically, the load threshold Th ₁ of the upper region 23 is determined based on the load detected when the reference load is added to the upper region 23. Similarly, the load threshold Th ₂ to the load threshold Th ₅ of the lower region 24 to the central region 27 are determined based on the load detected when the reference load is applied to each of the lower region 24 to the central region 27. It is done.

The drive waveforms Wa ₁ to Wa ₅ are information regarding the drive signal S ₃ for each region. The drive waveform Wa ₁ is a waveform determined so that the operator can fully recognize the haptic feedback by changing the amplitude, the frequency, and the like based on the haptic feedback generated by the drive signal S ₃ having the reference waveform. is there. Similarly, the driving waveforms Wa ₂ to Wa ₅ are each changed in amplitude, frequency, etc. based on the haptic feedback generated by the driving signal S ₃ having the reference waveform, so that the operator can fully recognize the haptic feedback. It is a waveform determined so as to be able to.

Note the control unit 8 as a modified example, it may store the driving signal S ₃ of each area in the database 80. The control unit 8 may store the drive waveform or drive signal for each region as a function in the database 80.

The touch threshold Th ₁₀ is a threshold for determining contact with the touch sensor 3. Control unit 8 determines a region where the touch threshold Th ₁₀ or more electrostatic capacitance is detected on the basis of the detection signals S ₁ to be input.

Control unit 8 determines by comparing the touch threshold value Th ₁₀ read from the capacitance and the database 80 for each area based on the detection signal S ₁ is operated finger touches area. Next, the control unit 8, when the region is determined and compared to the load based on the load signal S ₂ reads the load threshold value corresponding to the region from the database 80. The control unit 8, the load is greater than or equal to the load threshold, when the push operation on the region is determined, in order to generate haptic feedback, the drive signal S ₃ reads a driving waveform of the area from the database 80 Generate and drive the actuator 4 to present tactile feedback.

Control unit 8 outputs in electronic devices connected generated by the operation information S ₄ including the region information push operation is performed based on the determination result.

Hereinafter, the operation of the tactile sense presentation device 1 according to the present embodiment will be described with reference to the flowchart of FIG.

(Operation)
The control unit 8 of the tactile sensation presentation device 1 compares the capacitance for each region based on the detection signal S ₁ acquired from the touch sensor 3 with the touch threshold Th ₁₀ read from the database 80, and the operation finger Monitor for contact.

When “Yes” in Step 1 is established, that is, when the touch of the operating finger is detected (Step 1: Yes), the control unit 8 reads the load threshold value of the region where the touch is detected from the database 80 and reads the load signal. compared to the load based on S _2, it monitors whether or not the push operation is performed (Step2).

Control unit 8, when the push operation force is not less than the load threshold is determined (Step3: Yes), the contact from the database 80 reads out the driving waveform of the detection area and generates a drive signal S ₃ Then, it outputs to the actuator 4 and presents tactile feedback (Step 4).

Here, in step 3, the control unit 8 ends the process when the push operation is not determined (Step 3: No) and the operation is not continued, that is, the contact of the operation finger is not detected (Step 5: No). To do. Further, in step 5, when the contact of the operation finger is continuously detected (Step 5: Yes), the control unit 8 advances the process to step 3 and determines the push operation.

(Effect of embodiment)
The tactile sensation providing apparatus 1 can suppress damage to the piezoelectric element 40 when an unexpected load is applied. Specifically, in the tactile sensation presentation device 1, the operation unit 2 and the piezoelectric element 40 are not in direct contact with each other, and therefore, compared to a case where the operation unit or a pusher provided in the operation unit directly contacts the piezoelectric element. The damage of the piezoelectric element 40 can be suppressed when a load is applied.

Since the pusher 5 is attached to a place where the displacement of the metal shim 41 is large, the tactile sensation presentation apparatus 1 is sufficient while suppressing a decrease in load detection accuracy compared to the case where the pusher directly contacts the piezoelectric element. Haptic feedback can be presented.

The tactile sensation presentation device 1 performs load detection and vibration presentation by a single actuator 4 and sets a load threshold for each region in order to suppress variation in load detection due to a difference in position where an operation is detected. In order to suppress variation in tactile feedback due to a difference in position, a drive signal is determined for each region. Since the upper region 23 to the right region 26 of the present embodiment are located symmetrically with respect to the central region 27, ideally, the load detected by the actuator 4 and the vibration feedback to be presented are the same in each region. Actually different. In addition, the tactile sensation presentation apparatus 1 can be easily downsized because there is one actuator 4. Therefore, the tactile sense presentation device 1 can present sufficient tactile feedback while suppressing a decrease in load detection accuracy even when the tactile sense presentation device 1 is downsized.

As mentioned above, although some embodiment and modification of this invention were demonstrated, these embodiment and modification are only examples, and do not limit the invention based on a claim. These novel embodiments and modifications can be implemented in various other forms, and various omissions, replacements, changes, and the like can be made without departing from the scope of the present invention. In addition, not all combinations of features described in these embodiments and modifications are necessarily essential to the means for solving the problems of the invention. Further, these embodiments and modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Tactile sense presentation apparatus 2 Operation part 3 Touch sensor 4 Actuator 5 Pusher 8 Control part 12 Concave part 40 Piezoelectric element 41 Metal shim 200 Operation surface 405 Through-hole

Claims (7)

An operation unit having an operation surface;
A piezoelectric element for detecting a load applied to the operation surface, and an actuator having a metal shim integrated with the piezoelectric element;
A pusher provided between the operation part and the metal shim, which increases the amount of deformation of the metal shim due to the operation of pushing down the operation surface;
A tactile presentation device. The metal shim has a disc shape,
The presser is located in the center of the metal shim;
The tactile sense presentation device according to claim 1. The metal shim and the piezoelectric element have a disk shape,
The metal shim has a larger radius than the piezoelectric element,
The tactile sense presentation device according to claim 1. The piezoelectric element has a symmetrical shape around the pusher,
The tactile sense presentation device according to any one of claims 1 to 3. The piezoelectric element has a through hole,
The pusher is inserted into the through hole and deforms the piezoelectric element through the metal shim in accordance with an operation of pushing down the operation surface.
The tactile sense presentation device according to any one of claims 1 to 4. The actuator is supported by a support;
The support portion has a recess that allows the actuator to bend.
The tactile sense presentation device according to any one of claims 1 to 5. The actuator is configured to detect a load and add vibration to the operation surface,
A detection unit for detecting a position of an operation finger in contact with the operation surface;
A load threshold value determined for each region based on a load detected by adding a reference load to each of the plurality of regions defined on the operation surface, and a drive signal for each region for driving the actuator. A control unit that determines an operation based on a load threshold value of a region in which an operation finger is detected and drives the actuator by a drive signal corresponding to the region to present tactile feedback;
A tactile sensation presentation apparatus according to claim 1, comprising:

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