Control device, input system, and control method

A control device according to the embodiment includes an operation detecting unit and a driving unit. The operation detecting unit detects a pressing operation onto an operation surface of a panel having the operation surface. The driving unit drives a vibration element attached to the panel to vibrate the panel. Moreover, the driving unit generates an initial vibration having a lower frequency than that of a main vibration in advance of the main vibration when the pressing operation is detected by the operation detecting unit.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2017-157252, filed on Aug. 16, 2017, the entire contents of which are incorporated herein by reference.

FIELD

The embodiment discussed herein is directed to a control device, an input system, and a control method.

BACKGROUND

There is a conventional input system that gives a feel to a user to make the user recognize that the input system has received a user's operation onto an operation surface of a panel. In regard to the input system, there has been proposed a technology for generating a click feel by vibrating a vibration element at a voltage having a waveform obtained by applying an envelope to a sine wave when the operation surface of the panel is manipulated (see, e.g., Japanese Laid-open Patent Publication No. 2013-109429).

However, the conventional technology has room for improvement in improving an operational feeling to be given to a user when the same operational feeling as an operational feeling onto a mechanical switch is given to the user.

SUMMARY

A control device according to the embodiment includes an operation detecting unit and a driving unit. The operation detecting unit detects a pressing operation onto an operation surface of a panel having the operation surface. The driving unit drives a vibration element attached to the panel to vibrate the panel. Moreover, the driving unit generates an initial vibration having a lower frequency than that of a main vibration in advance of the main vibration when the pressing operation is detected by the operation detecting unit.

DESCRIPTION OF EMBODIMENT

Hereinafter, a control device, an input system, and a control method according to an embodiment will be explained in detail with reference to the accompanying drawings. In addition, the illustrative embodiment disclosed below is not intended to limit the present invention.

First, a configuration example of an input system1according to the embodiment will be described by usingFIG. 1A.FIG. 1Ais a diagram illustrating a configuration example of the input system1. As illustrated inFIG. 1A, the input system1according to the embodiment includes a panel10, a vibration element14, and a control device20.

The panel10includes a support plate11, a protective layer12, and a pressure sensor13. The pressure sensor13and the protective layer12are sequentially laminated on the support plate11. The protective layer12is formed of, for example, a resin member such as a resin film. The surface of the protective layer12is an operation surface15of the panel10.

The pressure sensor13is a sensor, e.g., a pressure-sensitive-resistance touch sensor, which can detect a contact position and an operational pressure onto the operation surface15of the panel10. The contact position and operational pressure are manipulated by a user U. The vibration element14is attached to the panel10, and is vibrated with a driving voltage Vo output from the control device20.

The control device20drives the vibration element14to vibrate the panel10in response to a user's pressing operation (hereinafter, may be referred to as user's operation) onto the operation surface15of the panel10. The control device20includes an operation detecting unit40and a driving unit41.

The operation detecting unit40detects a user's operation on the basis of the contact position detected by the pressure sensor13. The driving unit41drives the vibration element14to vibrate the panel10on the basis of a detection result of the user's operation detected by the operation detecting unit40.

When the user's operation is detected by the operation detecting unit40, the driving unit41drives the vibration element14to vibrate the panel10so as to give the same operational feeling as an operational feeling onto a mechanical switch to the user U. Hereinafter, although it will be explained that the user's operation is performed by a finger50of the user U, the user's operation may be performed by a stylus pen etc.

FIG. 1Bis a diagram illustrating the outline of a control method. An example of vibrations of the panel10is illustrated inFIG. 1B. As illustrated inFIG. 1B, when a pressing operation is detected by the operation detecting unit40, the control method according to the embodiment generates an initial vibration having a low frequency than that of a main vibration (times t1to t2), and then generates the main vibration with respect to the panel10(times t2to t3).

An initial vibration is a vibration for showing the user U a repulsive force when pressing an actual mechanical switch. In other words, an initial vibration can allow the panel10to provide a sense pushing a mechanical switch to the user U.

A main vibration is a vibration for giving a click feel of the mechanical switch to the user U. In other words, the control method according to the embodiment does not only give a click feel by using a main vibration, but also gives a depth feel of the mechanical switch by using an initial vibration in advance of the main vibration.

As a result, it is possible to give the same operational feeling as an operational feeling onto an actual mechanical switch to the user U, and thus it is possible to improve an operational feeling to be given to the user U.

Next, the configuration of an electronic system100including the input system1according to the embodiment will be described by usingFIG. 2.FIG. 2is a block diagram illustrating the electronic system100.

The electronic system100illustrated inFIG. 2is, for example, an in-vehicle system mounted on a vehicle. However, the embodiment is not limited to such an example. The electronic system may be a computer system etc. including PC (personal computer).

The electronic system100includes the input system1and a display device2. The input system1includes an input unit9and the control device20. The input unit9includes the panel10and the vibration element14described above. The pressure sensor13of the panel10is, for example, a pressure-sensitive-resistance touch sensor. However, the pressure sensor13may be a sensor other than the pressure-sensitive-resistance sensor.

The vibration element14is attached to the front face or back face of the panel10. The vibration element14is, for example, a linear resonance actuator. However, the vibration element14may be a piezoelectric element etc. Although it is not illustrated, the input unit9may include an amplifying unit that amplifies a driving voltage output from the control device20and outputs the amplified voltage to the vibration element14.

FIG. 3is a diagram illustrating an arrangement example of the vibration element14according to the embodiment. In the example illustrated inFIG. 3, the input unit9includes two vibration elements14. The two vibration elements14are arranged around the operation surface15. The number of the vibration elements14is not limited to two. Therefore, the number may be one, or may be three or more. Furthermore, the arrangement of the vibration elements14is not limited to the example illustrated inFIG. 3. For example, the vibration element14may be arranged at a position (e.g., the central portion of the operation surface15) corresponding to the operation surface15of the panel10.

Returning toFIG. 2, the control device20will be described. The control device20includes a storage21and a controller22. The storage21stores therein mode information30, timing information31, and operation determination information32. The mode information30is, for example, information indicating the type of vibration modes set via an input unit not illustrated. One of a fixed mode and a variation mode is set as the type of a vibration mode.

A fixed mode is a mode for vibrating the panel10in a fixed vibration pattern in response to a pressing operation of the user U onto the operation surface15of the panel10. A variation mode is a mode for vibrating the panel10in a vibration pattern according to the state of a pressing operation.

The timing information31is information for defining the occurrence time of each vibration, and includes information indicating first to third times T1to T3to be described later. The operation determination information32is information for determining a user's operation, and includes information indicating first to third threshold values Pth1to Pth3corresponding to operational pressures of the user U onto the operation surface15.

The controller22includes the operation detecting unit40and the driving unit41. The operation detecting unit40acquires detected information indicating a contact position and an operational pressure of the user U onto the operation surface15that are detected by the pressure sensor13. Furthermore, the operation detecting unit40acquires the operation determination information32stored in the storage21.

The operation detecting unit40detects an operation of the user U onto the operation surface15of the panel10on the basis of the detected information acquired from the pressure sensor13and the operation determination information32acquired from the storage21. The operation detecting unit40can detect various operations such as a pressing operation and a slide operation of the user U.

For example, when the contact position of the user U onto the operation surface15continues to be at the same position and the operational pressure is not less than the first threshold value Pth1, the operation detecting unit40can determine that there is a pressing operation of the user U onto the operation surface15.

When the pressing operation is detected by the operation detecting unit40, the driving unit41drives the vibration element14to vibrate the panel10with an initial vibration W1and then to vibrate the panel10with a main vibration W2having a higher frequency than that of the initial vibration W1.

Herein, a relationship between an operating force and an operation position onto a mechanical switch will be described.FIG. 4is a diagram illustrating operational feeling characteristics onto a mechanical switch. InFIG. 4, an operating force is a pressing force onto an operation surface of a mechanical switch, and an operation position is a push position onto the mechanical switch in a stroke direction.

As illustrated inFIG. 4, when a pressing operation of the user U onto the mechanical switch is started, the user U needs to increase an operating force from an operation position S0corresponding to push-start onto the mechanical switch to an operation position S1. When the operating force reaches F1at the operation position S1, a necessary operating force is decreased up to an operation position S2, and then the necessary operating force is increased. After that, the operating force reaches an operation position S3corresponding to an ending position.

Furthermore, when the user U starts an operation for releasing the finger50from the mechanical switch from the operation position S3, a necessary operating force is suddenly decreased from F2, but the necessary operating force is increased from the operation position S2to the operation position S1. The reason is because a rubber switch built in the mechanical switch is pushed down and then is returned. The user U instantaneously feels a pressure immediately before releasing the finger50from the mechanical switch.

Therefore, the driving unit41gives vibrations corresponding to areas61and62illustrated inFIG. 4to the panel10to give the same operational feeling as an operational feeling onto the mechanical switch to the user U. The area61is a predetermined range before and behind the operation position S2at which the operating force has the minimum value. The area62is a range from the operation position S2, immediately before releasing the finger50of the user U from the mechanical switch, to the operation position S1.

FIG. 5is a diagram illustrating an example of a vibration of the panel10generated by the driving unit41. As illustrated inFIG. 5, when a user's operation is detected by the operation detecting unit40, the driving unit41causes the panel10to generate the initial vibration W1and then causes the panel10to generate the main vibration W2. After that, the driving unit41causes the panel10to generate a sound source vibration W3. The vibrations W1to W3are a vibration in a depthwise direction (Z-axis direction illustrated inFIG. 1) of the panel10.

Herein, the sound source vibration W3is a waveform to present an operational sound to the user U. The sound source vibration W3is a waveform of a main frequency or an original sound that occurs during an operation of the mechanical switch as a simulated target. The sound source vibration W3is a vibration having a higher frequency than that of the main vibration W2.

In other words, the sound source vibration W3can allow the panel10to generate an operational sound when pushing down an actual mechanical switch. As described above, it is possible to give an operational feeling closer to a mechanical switch to the user U by presenting an operational sound of an actual mechanical switch. Furthermore, because the sound source vibration W3vibrates the panel10to generate an operational sound, a separate speaker for generation an operational sound is not required.

In other words, cost reduction of the input system1can be achieved. In addition, a sound caused by the sound source vibration W3is, for example, a clicky sound when pushing down the mechanical switch.

As described above, an operational feeling of a mechanical switch is presented by using the initial vibration W1and the main vibration W2, and an operational sound of the mechanical switch is presented by using the sound source vibration W3. In other words, an operational feeling of the mechanical switch can be presented by using an acoustic sense as well as a tactile sense. Therefore, it is possible to give the same operational feeling as that of the mechanical switch to the user U.

The driving unit41causes the panel10to generate the vibrations W1to W3on the basis of the type of vibration modes set in the storage21. It is preferable that the initial vibration W1has a frequency not more than 300 MHz and a frequency in a range of ½ to ¼ of the main vibration W2.

Next, the fixed mode and the variation mode described above will be described. Hereinafter, it will be described in the order of the fixed and variation modes. First, the fixed mode will be described. In the fixed mode, the driving unit41can generate the vibrations W1to W3on the basis of the timing information31and the operation determination information32stored in the storage21.

When the pressure of the user's operation is not less than the first threshold value Pth1on the basis of the operation determination information32stored in the storage21, the driving unit41detects that there is the operation of the user U onto the operation surface15. Then, the driving unit41applies a sinusoidal driving voltage Vo1to the vibration element14and causes the panel10to generate the initial vibration W1until the first time T1elapses from a detection timing (time t10) of the user's operation on the basis of the timing information31stored in the storage21.

As a result, in times t10to t11(first time T1), the panel10is caused to generate the initial vibration W1and thus the user U can be caused to feel a repulsive force when pushing the switch. Herein, the initial vibration W1is not limited to the shape of a sine wave. Therefore, the initial vibration W1may be the shape of a rectangle, a sawtooth wave, or a triangular wave.

Next, the driving unit41applies a sinusoidal driving voltage Vo2to the vibration element14in the second time T2between time t11and time t12on the basis of the timing information31stored in the storage21. The driving voltage Vo2is a voltage by which the frequency of the vibration element14becomes higher than the driving voltage Vo1.

As a result, a click feel can be given to the user U by instantaneously giving vibrations having relatively different frequencies to the user U. Furthermore, it is preferable that the main vibration W2has a comparatively short time. For example, the main vibration W2is a vibration within two periods of a sine wave. In other words, even if a sound is output from the panel10due to the main vibration W2, the output time is short.

Therefore, a sound output from the panel10can be restrained within the range in which the user U cannot recognize the sound. As a result, the user U can avoid getting an unpleasant feeling.

As described above, the driving unit41continuously generates the initial vibration W1and the main vibration W2. As a result, the driving unit41can give a repulsive force according to a mechanical switch to the user U and further give a click feel to the user U. In other words, it is possible to give the same operational feeling as that of an actual mechanical switch. Herein, “continuously generating the initial vibration W1and the main vibration W2” means that the initial vibration W1and the main vibration W2are generated seamlessly as illustrated inFIG. 5, but includes generating the initial vibration W1and the main vibration W2at short intervals.

Next, the driving unit41applies a driving voltage Vo3to the vibration element14to generate the sound source vibration W3in the third time T3between time t12and time t13on the basis of the timing information31stored in the storage21. The driving voltage Vo3is a voltage by which the frequency of the vibration element14becomes higher than the driving voltage Vo2.

As described above, the sound source vibration W3is a vibration for presenting an operational sound of the mechanical switch to the user U. Furthermore, the sound source vibration W3is, for example, a frequency at which the finger50of the user U cannot feel a vibration.

In other words, the initial vibration W1and the main vibration W2are vibrations for presenting an operational feeling of the mechanical switch to the user U by using a tactile sense, and the sound source vibration W3is a vibration for presenting an operational sound to the user U by using an acoustic sense.

As described above, in the fixed mode, the driving unit41can apply to the vibration element14driving voltages Vo respectively corresponding to the first to third times T1to T3according to the timing information31on the basis of the timing information31stored in the storage21so as to give the same operational feeling as an operational feeling onto the mechanical switch to the user U.

Next, the variation mode will be described. In the variation mode, the driving unit41generates the vibrations W1to W3on the basis of an operational pressure F onto the operation surface15detected by the pressure sensor13and the operation determination information32stored in the storage21.

FIG. 6is a diagram illustrating a relationship between the vibration of the panel10and the operational pressure F of the user U onto the operation surface15in the variation mode. In the example illustrated inFIG. 6, the user U starts a pressing operation at time t20, and then the operational pressure F of the user U onto the operation surface15is increased.

The driving unit41repeatedly determines whether the operational pressure F is not less than the first threshold value Pth1. When it is determined that the operational pressure F is not less than the first threshold value Pth1(time t21), the driving unit41applies the driving voltage Vo1to the vibration element14. As a result, the driving unit41causes the panel10to generate the initial vibration W1.

Next, the driving unit41determines whether the operational pressure F is not less than the second threshold value Pth2or is less than the first threshold value Pth1. When it is not determined that the operational pressure F is not less than the second threshold value Pth2or is less than the first threshold value Pth1, the driving unit41continues to apply the driving voltage Vo1to the vibration element14.

As a result, the driving unit41can cause the panel10to continuously generate the initial vibration W1so as to more appropriately give the user U a repulsive force when pushing the switch.

When the operational pressure F is not more than the first threshold value Pth1, the driving unit41sets a voltage to be applied to the vibration element14to zero to stop the vibration of the panel10. On the other hand, when it is determined that the operational pressure F is not less than the second threshold value Pth2(time t22), the driving unit41applies the driving voltage Vo2to the vibration element14within the second time T2(between time t22and time t23). As a result, the driving unit41can cause the panel10to generate the main vibration W2so as to give a click feel to the user U.

Next, the driving unit41determines whether the operational pressure F is not more than the third threshold value Pth3. When it is determined that the operational pressure F is not more than the third threshold value Pth3(time t23), the driving unit41applies the driving voltage Vo3to the vibration element14within the third time T3(between time t23and time t24). As a result, an operational sound can be presented to the user U.

As described above, in the variation mode, the driving unit41generates the vibrations W1to W3on the basis of the operational pressure F of the user U onto the operation surface15of the panel10and the operation determination information32stored in the storage21. For that reason, even if the operational pressure F and the contact time in the pressing operation are different between users, a suitable operational feeling for each of the users can be given.

Next, a relationship between an image displayed on the display device2and an input operation of the user U will be described.FIG. 7is a diagram illustrating an example of a screen65that is displayed on the display device2. The screen65illustrated inFIG. 7is a menu screen that is displayed on the display device2. Six icons71to76(hereinafter, may be collectively referred to as “icon70”) are displayed on the menu screen.

When the user U performs a pressing operation for selecting the icon70with respect to the operation surface15, the driving unit41causes the panel10to sequentially generate the vibrations W1to W3described above.

Herein, the operation determination information32in the storage21includes, for each of the six icons71to76, different combination information of the vibrations W1to W3, the first to third threshold values Pth1to Pth3, and the first to third times T1to T3.

In other words, when a pressing operation onto the icon70is detected, the driving unit41can generate the vibrations W1to W3and change the vibrations W1to W3for each the icon70.

As described above, a different feel for each the icon70can be given to the user U by generating the different vibrations W1to W3for each the icon70. As a result, the user U can be caused to recognize an operation onto each the icon70by using a difference of a tactile sense so as to improve operationality. Vibrations for the six icons71to76may be all the same vibrations W1to W3.

Next, a processing procedure that is executed by the control device20according to the embodiment will be described by usingFIG. 8.FIG. 8is a flowchart illustrating a processing procedure that is executed by the control device20. A processing procedure to be described below is performed by the controller22of the control device20.

As illustrated inFIG. 8, the controller22first determines whether a mode is a fixed mode (Step S100). When the mode is the fixed mode (Step S100: Yes), the controller22determines whether the operational pressure F is not less than the threshold value Pth1(Step S101).

When the operational pressure F is not less than the threshold value Pth1(Step S101: Yes), the driving unit41generates the initial vibration W1(Step S102) and then generates the main vibration W2(Step S103). After that, the driving unit41generates the sound source vibration W3to generate an operational sound (Step S104), and terminates the process. Furthermore, when the operational pressure F is less than the threshold value Pth1(Step S101: No), the controller22repeatedly performs the process of Step S101.

On the other hand, when the mode is not the fixed mode (Step S100: No), the controller22determines whether the operational pressure F is not less than the threshold value Pth1(Step S105). When the operational pressure F is less than the threshold value Pth1(Step S105: No), the controller22continues to perform the process of Step S105.

Furthermore, when the operational pressure F is not less than the threshold value Pth1(Step S105: Yes), the driving unit41generates the initial vibration W1(Step S106), and determines whether the operational pressure F is not less than the threshold value Pth2(Step S107).

When the operational pressure F is less than the threshold value Pth2(Step S107: No), the controller22determines whether the operational pressure F is less than the threshold value Pth1(Step S108). Herein, when the operational pressure F is less than the threshold value Pth1(Step S108: Yes), the controller22stops the initial vibration W1(Step S109) and terminates the process. Furthermore, when the operational pressure F is not less than the threshold value Pth1(Step S108: No), the controller22continues to perform the process after Step S106.

On the other hand, when the operational pressure F is not less than the threshold value Pth2(Step S107: Yes), the driving unit41generates the main vibration W2(Step S110) and determines whether the operational pressure F is not more than the threshold value Pth3(Step S111).

When the operational pressure F is not more than the threshold value Pth3(Step S111: Yes), the driving unit41generates the operational sound (S112) and terminates the process. Furthermore, when the operational pressure F is larger than the threshold value Pth3(Step S111: No), the controller22continues to perform the determination process of Step S111.

As described above, the control device20according to the embodiment includes the operation detecting unit40and the driving unit41. The operation detecting unit40detects a pressing operation onto the operation surface15of the panel10having the operation surface15. The driving unit41drives the vibration element14attached to the panel10to vibrate the panel10. Furthermore, when the pressing operation is detected by the operation detecting unit40, the driving unit41generates the initial vibration W1having a lower frequency than that of the main vibration W2in advance of the main vibration W2. Therefore, the control device20according to the embodiment can give the same operational feeling as an operational feeling onto a mechanical switch to the user U and thus can improve an operational feeling to be given to the user U.

A case where the vibration element14generates the vibrations W1to W3in a depthwise direction of the panel10has been explained in the embodiment described above. However, the present embodiment is not limited to this. In other words, the embodiment can be applied to a case where the vibration element14vibrates the panel10along an X-axis direction or a Y-axis direction illustrated inFIG. 1A.