JP6852664B2 - Tactile presentation device, tactile presentation system, computer program and storage medium - Google Patents

Description

The present invention relates to a tactile presentation device, a tactile presentation system, a computer program and a storage medium.

Conventionally, a configuration has been provided in which a tactile sensation is presented when the user touches the touch panel. In the configuration that presents the sense of touch, the frequency at which a person can easily detect the sense of touch is about several tens of Hz. As a configuration for generating vibration of about several tens of Hz, a configuration in which a vibrating body is placed below the vibrating object to be vibrated, the vibration of the vibrating body is propagated to the vibrating object, and the vibrating object is indirectly vibrated is disclosed. (See, for example, Patent Document 1).

Japanese Patent No. 60789935

However, in the configuration of Patent Document 1 described above, since the vibration target is indirectly vibrated by utilizing resonance, it is not possible to realize a steep vibration rising characteristic, and the tactile sensation is appropriately presented. There is a problem that cannot be done. In order to realize the rising characteristic of steep vibration, it is necessary to directly vibrate the vibrating object without using resonance. As a configuration for directly vibrating the vibrating object, a configuration in which the vibrating object is vibrated by using an actuator can be considered. Specifically, if the touch panel is to be vibrated, a configuration is conceivable in which the touch panel is suspended by a leaf spring and connected to the movable yoke, an electromagnetic force is generated in the fixed yoke, and the movable yoke is sucked.

In such a configuration, the suction force of the actuator that sucks the movable yoke is significantly affected by the yoke gap distance, which is the gap distance in the suction direction between the fixed yoke and the movable yoke, so that the influence of the yoke gap distance is reduced. There is a need. However, in the configuration in which the touch panel is suspended at a plurality of places by leaf springs, the yoke gap distance varies due to individual differences during assembly. In addition, if the period of use is long, the yoke gap distance may vary due to the settling of the leaf spring due to aging. Therefore, it is necessary to devise so as not to change the tactile sensation even if the yoke gap distance changes.

The present invention has been made in view of the above circumstances, and an object of the present invention is to periodically measure the gap distance in the suction direction between the fixed yoke and the movable yoke to prevent individual differences and aging. It is an object of the present invention to provide a tactile presentation device, a tactile presentation system, a computer program and a storage medium capable of stably presenting a tactile sensation without being affected.

According to the first aspect of the present invention, the movable yoke (11) connected to the vibration target (3) and the fixed yoke (6) are provided, and an electromagnetic force is generated in the fixed yoke to attract the movable yoke. Then, the vibrating object is vibrated to present a tactile sensation. The measuring unit (10) measures the yoke gap distance, which is the gap distance between the fixed yoke and the movable yoke in the suction direction. The control unit (17) calibrates the yoke clearance distance measured by the measuring unit when in the neutral state, and uses the calibrated yoke clearance distance to apply the electromagnetic force generated in the fixed yoke when vibrating the vibrating object. To control.

Even if there is a variation in the yoke gap distance due to individual differences or changes over time, the vibration target can be vibrated while the variation is eliminated. As a result, by periodically measuring the gap distance between the fixed yoke and the movable yoke in the suction direction, it is possible to stably present the tactile sensation without being affected by individual differences or aging.

Perspective view schematically showing the overall configuration of the first embodiment Longitudinal side view showing the configuration of the actuator An exploded perspective view showing the components of the actuator Functional block diagram The figure which shows the relationship between the actuator suction force and the spring reaction force, and the yoke clearance distance (part 1). The figure which shows the relationship between a sensor current ratio and a sensor clearance distance Operation sequence Flowchart showing calibration process Flowchart showing consistency calculation process The figure which shows the relationship between the actuator suction force and the spring reaction force, and the yoke clearance distance (part 2). Operation sequence showing the second embodiment

(First Embodiment)
Hereinafter, the first embodiment of the present invention will be described with reference to FIGS. 1 to 10. As shown in FIG. 1, the tactile presentation system 1 includes a display 2 having a rectangular display surface 2a, a touch panel 3 (corresponding to a vibration target) covering the entire display surface 2a, and four corners of the display 2. It has four actuators 4a to 4d arranged below the. The touch panel 3 is made of a transparent material so that the user can visually recognize the icon or the like displayed on the display surface 2a.

In the present embodiment, the configuration in which the number of actuators is "4" is illustrated, but when the area of the display surface 2a is large or the weight of the display 2 or the touch panel 3 is large, the number of actuators is increased. Is also good. That is, any number of actuators may be designed as long as the display 2 and the touch panel 3 are evenly supported. The four actuators 4a to 4d have the same configuration, and the actuators 4a will be described as a representative.

As shown in FIGS. 2 and 3, the actuator 4a includes a case 5, a fixed yoke 6 fixed to the case 5, a bobbin 8 around which a winding coil 7 is wound, and a sensor circuit board. It has a gap distance sensor 10 mounted on a sensor circuit board 9, a movable yoke 11 arranged above the fixed yoke 6, and a leaf spring 12 (corresponding to an elastic member). One end of the leaf spring 12 is fixed to the case 5 from the bolt 13 and the nut 14, and the movable yoke 11 is caulked and fixed to the other end side to be integrated. The four corners of the lower surface of the display 2 and the other end of the movable yoke 11 are connected via a stay 15. That is, the four corners of the lower surface of the display 2 are suspended by the leaf springs 12.

When a drive current flows through the winding coil 7, a magnetic field is generated around the winding coil 7, an electromagnetic force is generated in the fixed yoke 6, an actuator attractive force is generated, and the movable yoke 11 is attracted and integrated. The leaf spring 12 is displaced. When the drive current to the winding coil 7 is stopped, the actuator suction force disappears, and the leaf spring 12 tries to return to the original position, that is, the position before the actuator suction force is generated. At this time, since the leaf spring 12 is connected to the display 2 via the stay 15, the display 2 and the touch panel 3 vibrate integrally in the vertical direction, and when the user is touching the touch panel 3, the display spring 12 and the touch panel 3 vibrate in the vertical direction. Vertical vibrations are presented as a tactile sensation.

The gap distance sensor 10 is arranged below the movable yoke 11, and has a light emitting portion that emits infrared light toward the lower surface portion of the movable yoke 11 and the emitted infrared light is reflected by the lower surface portion of the movable yoke 11. It has a light receiving unit that receives reflected light. The light receiving unit is, for example, a phototransistor. When the gap distance sensor 10 receives the reflected light by the light receiving unit, the gap distance sensor 10 measures the amount of the reflected light received and converts it into a current value, and outputs the current value as a sensor current value. Gap distance The sensor gap distance (“Xa” in FIG. 2), which is the vertical gap distance between the sensor 10 and the lower surface of the movable yoke 11, is the gap in the suction direction between the fixed yoke 6 and the movable yoke 11. It is wider than the yoke gap distance (“Xb” in FIG. 2), which is a distance, and the following relationship is established between the sensor gap distance and the yoke gap distance.
Sensor clearance distance = York clearance distance + offset

The tactile presentation system 1 has a functional block shown in FIG. 4 as an electrical configuration. The tactile presentation system 1 includes a host 16, a control microcomputer 17, and the above-mentioned four actuators 4a to 4d. The control microcomputer 17 has a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an I / O (Input / Output), and is stored in a non-transitional substantive storage medium. By executing the computer program, the process corresponding to the computer program is executed, and the overall operation of the tactile presentation system 1 is controlled. In the present embodiment, since the four actuators 4a to 4d are the control targets, one control microcomputer 17 is provided separately from the four actuators 4a to 4d, and the four actuators 4a to 4d are controlled by one. Although the configuration controlled by the microcomputer 17 is illustrated, if one actuator is to be controlled, the function of the control microcomputer 17 may be provided inside the actuator. That is, the tactile presentation device includes at least one actuator and a control microcomputer that controls at least one actuator.

The actuators 4a to 4d each include a drive circuit 18 for passing a drive current through the winding coil 7 and a clearance distance sensor 10. When the user touches the touch panel 3, the gap distance sensor 10 measures the amount of reflected light according to the user's operation, converts it into a current value, and outputs the current value as a sensor current value to the control microcomputer 17. The control microcomputer 17 identifies the actuators 4a to 4d by ID, and when the sensor current value is input from the gap distance sensor 10, it is specified that the user has touched the touch panel 3, and the sensor current values of the actuators 4a to 4d are used. An operation detection signal that can identify the output source of the obtained gap distance is output to the host 16.

When the host 16 inputs an operation detection signal from the control microcomputer 17, the host 16 identifies the touch position where the user is touching the touch panel 3 by a touch panel controller (not shown), and associates the specified touch position with the display object. Decide whether to present a tactile sensation. In the present embodiment, since the actuators 4a to 4d are arranged below the four corners of the display 2, the touch panel controller determines the displacement of the gap distance obtained from the sensor current value output from each gap distance sensor 10. , The touch position where the user is touching the touch panel 3 can be specified by proportionally allocating according to the arrangement of the actuators 4a to 4d. When the host 16 determines the tactile sensation to be presented to the user, the host 16 outputs a vibration command signal capable of specifying the data defining the tactile sensation to be presented to the control microcomputer 17 based on the determined tactile sensation.

When the control microcomputer 17 inputs a vibration command signal from the host 16, the control microcomputer 17 identifies the data defining the tactile presentation from the input vibration command signal. The control microcomputer 17 specifies a pressing detection value corresponding to a pressing force applied to the touch panel 3 when the user touches the touch panel 3 due to the displacement of the clearance distance obtained from the sensor current value input from the clearance distance sensor 10. When the specified pressure detection value has a predetermined relationship with the threshold value, a drive signal corresponding to the specified data is output to the drive circuit 18. That is, the control microcomputer 17 sets a threshold value for each area of the button switch displayed on the touch panel 3, and outputs a drive signal to the drive circuit 18 when the pressure detection value exceeds the threshold value. In this case, the threshold value is used to distinguish operations such as lightly pressing the touch panel 3 for a short time, lightly pressing for a long time, deeply pressing for a short time, and deeply pressing for a long time. Is the threshold value of. The drive signal output by the control microcomputer 17 to the drive circuit 18 is a PWM signal. Further, the pressing detection value is a total value obtained by multiplying the amount of change in output from the state in which the pressing force is not applied in each gap distance sensor 10 by a constant determined by the mechanical structure.

When the drive signal is input from the control microcomputer 17, the drive circuit 18 outputs the drive current specified by the input drive signal to the winding coil 7 and generates a magnetic field around the winding coil 7 to generate a fixed yoke 6 An electromagnetic force is generated in the coil to generate an actuator attraction force.

Here, the relationship between the above-mentioned yoke gap distance and the actuator suction force will be described. The yoke gap distance is preferably 1 mm or less in order to effectively use the actuator suction force. When the actuator suction force becomes large, the moving distance of the movable yoke 11 becomes long, and when the movable yoke 11 collides with the fixed yoke 6, a collision sound is generated. Since the generation of a collision sound causes discomfort to the user, the control microcomputer 17 needs to control the actuator suction force so that the movable yoke 11 does not collide with the fixed yoke 6. That is, it is necessary for the control microcomputer 17 to measure the yoke clearance distance and use the measured yoke clearance distance to feedback-control the drive current flowing through the winding coil 7 to control the actuator suction force.

The relationship between the actuator suction force and the spring reaction force (corresponding to the elastic force) and the yoke gap distance shows the characteristics shown in FIG. In FIG. 5, the solid line shows the relationship between the actuator suction force and the yoke gap distance, and the broken line shows the relationship between the spring reaction force and the yoke gap distance. The spring reaction force is an elastic force generated when the leaf spring 12 is displaced from the neutral state, and the neutral state is a state in which the actuator suction force is not generated.

The actuator attraction force is inversely proportional to the yoke clearance distance, and is proportional to the square of the current flowing through the winding coil 7 in a range where magnetic saturation of the electromagnet does not occur. Assuming that the actuator suction force is "Fcoil", the electromagnetic force generation coefficient is "α", the current value of the drive current flowing through the winding coil 7 is "i", and the yoke clearance distance is "L", the following relationship is established. To establish.
Fcoil = α × i∧2 / L (∧ indicates exponentiation)

On the other hand, the spring reaction force is proportional to the position displacement of the leaf spring 12 from the neutral state. Assuming that the spring reaction force is "Fk", the elastic modulus is "k", and the displacement amount is "ΔL", the following relationship is established.
Fk = −k × ΔL
When the actuator suction force and the spring reaction force are balanced and the leaf spring 12 is stopped, the following relationship is established.
Fcoil + Fk = 0

In FIG. 5, the characteristics when the current value of the drive current flowing through the winding coil 7 on the solid line A1 is “i1”, and when the current value of the drive current flowing through the winding coil 7 on the solid line A2 is “i2”. Assuming that the characteristic, the solid line A3 is the characteristic when the current value of the drive current flowing through the winding coil 7 is "i3", the following relationship is established.
i1 <i2 <i3

In this case, if the drive current is less than the current value "i3", the movable yoke 11 does not collide with the fixed yoke 6, but if the drive current is less than the current value "i3", the movable yoke 11 collides with the fixed yoke 6. That is, the maximum current value of the drive current at which the movable yoke 11 does not collide with the fixed yoke 6 is the current value “i3”.

Next, the gap distance sensor 10 will be described. As described above, when the gap distance sensor 10 receives the reflected light by the light receiving unit, the gap distance sensor 10 measures the amount of the reflected light received and converts it into a current value, and outputs the current value as a sensor current value to the control microcomputer 17. To do. When the control microcomputer 17 inputs the sensor current value from the gap distance sensor 10, the input sensor current value is converted into a distance, and the vertical gap distance between the gap distance sensor 10 and the lower surface portion of the movable yoke 11 is calculated. Specify as the sensor clearance distance. In this case, as described above, the following relationship is established between the sensor clearance distance and the yoke clearance distance.
Sensor clearance distance = yoke clearance distance + offset That is, in the present embodiment, the yoke clearance distance can be obtained by obtaining the sensor gap distance and subtracting the offset from the obtained sensor gap distance.

The relationship between the sensor current value and the sensor clearance distance shows the characteristics shown in FIG. The vertical axis is the sensor current ratio, which is a value obtained by normalizing the measured sensor current value with a specific sensor current value. The horizontal axis is the sensor clearance distance.

In FIG. 6, the change in the sensor clearance distance and the change in the sensor current ratio are not in a linear relationship. When the sensor clearance distance is relatively small and is about 1 mm or less, almost all of the infrared light emitted from the light emitting portion reaches the lower surface portion of the movable yoke 11, and the sensor current ratio increases as the sensor clearance distance increases. Increases. On the other hand, when the sensor gap distance is relatively large and is about 1 mm or more, the infrared light emitted from the light emitting portion is attenuated before reaching the lower surface portion of the movable yoke 11, and as the sensor gap distance increases. The sensor current ratio decreases.

The sensor current value is affected by the individual difference of the clearance distance sensor 10, the temperature effect, the reflectance of light in the reflector, etc., but the sensor current value measured as described above should be normalized with a specific sensor current value. So, these effects can be offset. For example, in a phototransistor generally used for a gap distance sensor 10, the sensor current value increases regardless of the amount of reflected light when the temperature rises, but the temperature is normalized by dividing by a specific sensor current value. The impact can be mitigated. Further, the individual difference of the gap distance sensor 10 can be similarly reduced. Here, for the specific sensor current value used for normalization, it is mechanically restricted to adjust the position of the movable yoke 11 so that the current value output from the clearance distance sensor 10 becomes the maximum sensor current value. For reasons of difficulty, it is the sensor current value in the neutral state.

However, the sensor clearance distance is unknown from the sensor current value in the neutral state, and the change in the sensor clearance distance and the sensor current ratio are obtained only by the sensor current ratio normalized by the sensor current value in the neutral state where the sensor clearance distance is unknown. The accuracy is low because the ratio with the change of the sensor changes depending on the sensor clearance distance. Therefore, it is necessary to accurately obtain the sensor clearance distance when normalizing the sensor current value.

The process of accurately determining the sensor clearance distance in the neutral state is defined as the calibration process (calibration). Since the variation in current measurement accuracy, magnetomotive force, spring constant, etc. is smaller than the variation in sensor clearance distance, the accuracy of current measurement, magnetomotive force, and spring constant are treated as having no error.

Next, the operation of the above configuration will be described with reference to FIGS. 7 to 10. FIG. 7 shows an operation sequence between the host 16 and the control microcomputer 17, and FIGS. 8 and 9 show the calibration process and the consistency calculation process executed by the control microcomputer 17, respectively. Here, the case where the tactile presentation system 1 is mounted on the vehicle will be described.

When the host 16 detects the user's boarding by switching the accessory signal from off to on, for example (A1), the host 16 needs to output a start request signal to the control microcomputer 17 and shift the tactile presentation system 1 to a state in which tactile presentation is possible. It is determined whether or not there is (A2). When the host 16 determines that it is necessary to shift the tactile presentation system 1 to a state in which the tactile presentation system 1 can be presented (A2: YES), the host 16 waits for the input of the activation response signal from the control microcomputer 17.

When the control microcomputer 17 inputs a start request signal from the host 16, the control microcomputer 17 shifts from the stopped state to the start state (B1), outputs a start response signal to the host 16, and shifts to the calibration process described in detail later (B2, Corresponds to the calibration procedure). The control microcomputer 17 starts the calibration process, and when the calibration process is completed, waits for the input of the tactile request data from the host 16.

When the host 16 inputs the activation response signal from the control microcomputer 17, it displays on a display device (A3) that the preparation for tactile presentation is completed (A3), and indicates whether or not the user has performed a touch operation on the touch panel 3. Monitor (A4). When the host 16 determines that tactile presentation is necessary due to the user performing a touch operation on the touch panel 3 (A5: YES), the host 16 outputs tactile request data to the control microcomputer 17.

When the tactile request data is input from the host 16, the control microcomputer 17 identifies the input tactile request data (B3) and uses the sensor clearance distance obtained by the calibration process to generate the tactile sensation to be presented (B4, Corresponds to the electromagnetic force control procedure). The control microcomputer 17 outputs the drive signal to the actuators 4a to 4d, and when it is determined that the generated tactile presentation is completed (B5: YES), the control microcomputer 17 outputs the tactile presentation completion data to the host 16.

When the host 16 inputs the tactile presentation completion data from the control microcomputer 17, it determines whether or not the tactile presentation system 1 needs to be maintained in a tactile presentation capable state (A6). When the host 16 determines that the tactile presentation system 1 needs to be maintained in a tactile presentation capable state (A6: YES), the host 16 returns to step A4 described above, and repeats step A4 and subsequent steps. When the host 16 determines that it is no longer necessary to maintain the tactile presentation system 1 in a tactile presentation capable state (A6: NO), the host 16 outputs a stop request signal to the control microcomputer 17, and a stop response signal from the control microcomputer 17. Wait for input.
When the control microcomputer 17 inputs a stop request signal from the host 16, the control microcomputer 17 shifts from the start state to the stop state (B6) and outputs a stop response signal to the host 16.
When the host 16 inputs a stop response signal from the control microcomputer 17, the host 16 displays on a display device (A7) that the tactile presentation is completed (A7).

Next, the calibration process executed by the control microcomputer 17 will be described. In the present embodiment, the case where the control microcomputer 17 executes the calibration process immediately after the transition from the stopped state to the started state is described, but in addition to immediately after the transition from the stopped state to the started state, it takes a long time. The calibration process may be executed even when the variation in the position displacement generated by each of the actuators 4a to 4d becomes large during the use of the above, or when the user performs a predetermined operation, or the like. That is, the control microcomputer 17 may execute the calibration process at any timing.

When the control microcomputer 17 starts the calibration process, the control microcomputer 17 sets the drive current to "0" (S1). In this state, the actuator suction force is not generated, and the movable yoke 11 is not sucked. Next, the control microcomputer 17 measures the sensor current value input from the gap distance sensor 10 in this state. In this case, the control microcomputer 17 may improve the measurement accuracy by using the average value or the effective value of the sensor current values in the period of the preset time width or by waiting for the sensor current value to stabilize.

Next, the control microcomputer 17 sets the target position displacement to be gradually larger than the previous target position displacement (S3), feedback-controls the drive current, and inputs the drive current and the clearance distance sensor 10 at that time. The current value is measured (S4). That is, when the drive current increases, the actuator attraction force increases, the spring reaction force increases in proportion to the position displacement of the leaf spring 12 from the neutral state, and the actuator stops at a position where the actuator attraction force and the spring reaction force are balanced. Therefore, the control microcomputer 17 sets the displacement at the position where the actuator attraction force and the spring reaction force are balanced as the target position displacement, and feedback-controls the drive current.

The control microcomputer 17 monitors the sensor current value and the position of the leaf spring 12 calculated from the sensor current value during the feedback control of the drive current, and the sensor current value or the position of the leaf spring 12 is a predetermined threshold value during the feedback control. It is determined whether or not the above change has occurred (S5). If the control microcomputer 17 determines that the sensor current value or the position of the leaf spring 12 has changed to or more than a predetermined threshold value (S5: YES), there is a possibility that disturbance such as a user's touch operation or running vibration has occurred. , The calibration process is interrupted. Further, the control microcomputer 17 monitors the user's touch operation during the feedback control, and determines whether or not the user's touch operation is performed during the feedback control (S6). If the control microcomputer 17 determines that the user's touch operation has been performed during the feedback control, the calibration process is also interrupted in this case as well.

The control microcomputer 17 estimates the user's operation amount from the deviation amount between the assumed position displacement and the actual position displacement from the drive current, and if the operation amount exceeds a predetermined threshold value and exhibits a tactile sensation, the control microcomputer 17 is calibrated. The user's operation can be continuously detected even while the operation process is being executed, and the tactile sensation can be presented. Further, when the calibration process is interrupted, the control microcomputer 17 detects the operation amount using the sensor clearance distance in the neutral state calculated last, and does not update the sensor clearance distance in the neutral state.

The control microcomputer 17 waits for a time in which the predetermined position stabilizes in order to improve the measurement accuracy, that is, a predetermined feedback control time elapses (S7). When the control microcomputer 17 determines that the predetermined feedback control time has elapsed (S7: YES), the control microcomputer 17 shifts to the consistency calculation process for obtaining the sensor clearance distance at which the consistency is maximized (S8).

The control microcomputer 17 assumes a sensor clearance distance in a neutral state, and calculates the positional displacement of the sensor clearance distance when a drive current in the actuators 4a to 4d is applied using the relationship between the actuator attraction force and the spring reaction force. .. By executing the consistency calculation process, the control microcomputer 17 assumes a sensor clearance distance in a neutral state that has not been calculated accurately, and the sensor clearance distance that maximizes the consistency with the actually measured sensor current ratio. Ask for.

When the control microcomputer 17 starts the consistency calculation process, the sensor gap distance in the neutral state is set to "X0", the sensor current value input from the gap distance sensor 10 in the neutral state is set to "Isout0", and the drive current is set to "Idrv1". Then, the sensor current value input from the gap distance sensor 10 when the drive current "Idrv1" is passed through the winding coil 7 is set to "Isout1". The control microcomputer 17 is a sensor that maximizes the consistency of the sensor current value "Isout0", the drive current "Idrv1", and the sensor current value "Isout1" when the drive current "Idrv1" is passed through the winding coil 7 in the neutral state. The gap distance "X0" is calculated. In the control microcomputer 17, the minimum value of the sensor clearance distance 10 in the design is set to "X0MIN", the maximum value is set to "X0MAX", the sensor clearance distance is temporarily placed in the variable "XT0", and the variable "XT0" is set to the minimum value "X0MIN". ”To the maximum value“ X0MAX ”.

The control microcomputer 17 sets "X0MIN" as the initial value of the sensor clearance distance "XT0", sets a sufficiently large value for the error MIN (S11), and sets the sensor current ratio and the sensor clearance distance shown in FIG. 6 to each other. Using the relationship, the sensor current ratio at the sensor clearance distance "XT0" is obtained as "Israt0" (S12). In the actual processing, the control microcomputer 17 interpolates from the relationship between the sensor gap distance and the sensor current ratio of a plurality of sensors corresponding to the graph characteristics on the software.

Next, the control microcomputer 17 uses the neutral sensor current value "Isout0" as a reference, and when the output ratio conversion coefficient of the gap distance sensor 10 is "Isconv", the output ratio conversion coefficient "Isconv" is calculated by the following formula. (S13).
Isconv = Israt0 / Isout0

Next, the control microcomputer 17 sets the sensor current ratio when the movable yoke 11 is sucked to "Isra1", and obtains the sensor current ratio "Isra1" by the following formula (S14).
Isra1 = Isconv x Isout1

Further, the control microcomputer 17 uses the relationship between the sensor current ratio and the sensor clearance distance shown in FIG. 6 to obtain the sensor clearance distance “X1” in the sensor current ratio “Isra1” (S15).
Next, the control microcomputer 17 sets the actuator suction force as "Fcoil", and obtains the actuator suction force "Fcoil" by the following formula (S16).
Fcoil = α × Idrv1 ∧ 2 / (X1-ds) (∧ indicates power)
Note that "dz" is an offset between the sensor clearance distance and the yoke clearance distance.

Next, the control microcomputer 17 sets the spring reaction force to "Fk" and obtains the spring reaction force "Fk" by the following formula (S17).
Fk = -k × (X1-XT0)
The control microcomputer 17 obtains the error between the actuator suction force "Fcoil" and the spring reaction force "Fk" by the following formula (S18).
Error = | Spring reaction force + Actuator suction force | (| A | indicates the absolute value of A)

The control microcomputer 17 compares the calculated error with the error MIN, determines whether or not the calculated error exceeds the error MIN, and evaluates the magnitude of the calculated error (S19). When the control microcomputer 17 determines that the calculated error is smaller than the error MIN (S19: YES), the error MIN = error and the sensor clearance distance "X0" = "XT0" (S20).

The control microcomputer 17 increases the sensor clearance distance "XT0" by a predetermined step amount "STEPX" (S21). That is, the control microcomputer 17 sets the suction target position displacement of the movable yoke 11 so as to gradually increase from the previous target position displacement. The step size “STEPX” is a step of the sensor clearance distance “XT0” used in the calculation for obtaining consistency, and is a value predetermined from the time allowed in the calibration process and the required accuracy.

The control microcomputer 17 sets the maximum value of the sensor clearance distance by design to "X0MAX", and compares the sensor clearance distance "XT0" increased by "STEPX" with the maximum value "X0MAX" (S22). When the control microcomputer 17 determines that the sensor clearance distance "XT0" does not exceed the maximum value "X0MAX" (S22: NO), the control microcomputer 17 returns to step S12 described above, and repeats step S12 and subsequent steps. When the control microcomputer 17 determines that the sensor clearance distance "XT0" exceeds the maximum value "X0MAX" (S22: YES), the control microcomputer 17 ends the consistency calculation process.

When the consistency calculation process is completed, the control microcomputer 17 determines whether or not there is a position that satisfies "spring reaction force> actuator suction force" (S9). When the control microcomputer 17 determines that there is a position satisfying "spring reaction force> actuator suction force" (S9: YES), the control microcomputer 17 returns to step S3 described above, and repeats step S3 and subsequent steps. When the control microcomputer 17 determines that there is no position satisfying "spring reaction force> actuator suction force" (S9: NO), the control microcomputer 17 specifies the estimated sensor clearance distance as the sensor clearance distance in the neutral state (S10), and performs calibration processing. To finish. By determining that there is no position that satisfies "spring reaction force> actuator suction force", the control microcomputer 17 specifies that there is no equilibrium point at which the actuator suction force and the spring reaction force are balanced, as shown in FIG. be able to.

As described above, according to the first embodiment, the following effects can be obtained.
In the tactile presentation system 1, an electromagnetic force is generated in the fixed yoke 6 to attract the movable yoke 11, and the touch panel 3 is vibrated to present the tactile sensation. The gap distance is obtained, and the electromagnetic force generated in the fixed yoke 6 when the touch panel 3 is vibrated is controlled by using the sensor gap distance obtained by executing the calibration process. Even if there is a variation in the yoke gap distance due to individual differences or changes over time, the vibration target can be vibrated while the variation is eliminated. As a result, by periodically measuring the gap distance between the fixed yoke 6 and the movable yoke 11 in the suction direction, it is possible to stably present the tactile sensation without being affected by individual differences or aging. ..

(Second embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. The same parts as those in the first embodiment described above will be omitted, and different parts will be described. In the second embodiment, the control microcomputer 17 stores the sensor clearance distance in the neutral state obtained by executing the calibration process in the storage area.

When the control microcomputer 17 inputs a start request signal from the host 16, the control microcomputer 17 shifts from the stopped state to the start state (B1), outputs a start response signal to the host 16, and then uses the sensor gap distance in the neutral state as the sensor gap distance this time. Identify (B11). The control microcomputer 17 specifies the sensor clearance distance stored in the storage area, that is, the sensor clearance distance in the neutral state obtained in the previous calibration process as the previous sensor clearance distance (B12), and this time the sensor clearance distance and the previous time. It is determined whether or not the difference from the sensor clearance distance is equal to or greater than a predetermined value (B13).

When the control microcomputer 17 determines that the difference between the sensor clearance distance this time and the sensor clearance distance last time is equal to or greater than a predetermined value (B13: YES), the control microcomputer 17 shifts to the calibration process described in the first embodiment described above (B2). ). That is, the control microcomputer 17 starts the calibration process, and when the calibration process is completed, waits for the input of the tactile request data from the host 16.

On the other hand, when the control microcomputer 17 determines that the difference between the sensor clearance distance this time and the sensor clearance distance last time is not equal to or more than a predetermined value (B13: NO), the control microcomputer 17 does not shift to the calibration process and inputs the tactile request data from the host 16. Wait. After that, when the control microcomputer 17 inputs the tactile request data from the host 16, the input tactile request data is specified (B3), and the sensor gap distance obtained by the calibration process is used to generate the tactile sensation to be presented. (B4), the same process as in the first embodiment described above is executed.

That is, if the difference between the sensor clearance distance this time and the previous sensor clearance distance is equal to or greater than a predetermined value, the control microcomputer 17 executes the calibration process and uses the latest sensor clearance distance obtained by executing the calibration process. To generate the tactile sensation to be presented. On the other hand, the control microcomputer 17 does not execute the calibration process unless the difference between the sensor gap distance this time and the previous sensor gap distance is equal to or more than a predetermined value, and obtains the sensor gap distance obtained by executing the previous calibration process. Use to generate a tactile sensation to present. The control microcomputer 17 omits the calibration process if the difference between the sensor clearance distance this time and the sensor clearance distance last time is within the allowable range.

As described above, according to the second embodiment, the same effect as that of the first embodiment can be obtained. Also, if the difference between the sensor clearance distance this time and the previous sensor clearance distance is greater than or equal to the predetermined value, the calibration process is executed, but if it is not greater than or equal to the predetermined value, the calibration process is not executed. By omitting it, the power consumption required to execute the calibration process can be suppressed.

(Other embodiments)
The present disclosure has been described in accordance with the examples, but it is understood that the present disclosure is not limited to the examples and structures. The present disclosure also includes various modifications and modifications within an equal range. In addition, various combinations and forms, as well as other combinations and forms containing only one element, more or less, are also within the scope of the present disclosure.
The configuration is not limited to the configuration applied to the vehicle, and may be a configuration applied to other uses.
The processing performed by the control microcomputer 17 may be performed by the host 16, or the processing performed by the host 16 may be performed by the control microcomputer 17, and how the processing performed by the host 16 and the processing performed by the control microcomputer 17 are distributed. You may.

In the drawing, 1 is a tactile presentation system, 3 is a touch panel, 6 is a fixed yoke, 10 is a gap distance sensor (measurement unit), 11 is a movable yoke, 12 is a leaf spring (elastic member), and 17 is a control microcomputer (control unit). Is.

Claims (8)

A movable yoke (11) connected to a vibrating object (3) and a fixed yoke (6) are provided, and an electromagnetic force is generated in the fixed yoke to attract the movable yoke to vibrate the vibrating object. A tactile presentation device that presents tactile sensation.
A measuring unit (10) for measuring the yoke gap distance, which is the gap distance between the fixed yoke and the movable yoke in the suction direction,
Control that calibrates the yoke gap distance measured by the measuring unit in the neutral state and controls the electromagnetic force generated in the fixed yoke when vibrating the vibrating object by using the calibrated yoke gap distance. A tactile presentation device including a part (17). The control unit sets the suction target position displacement of the movable yoke to be gradually larger than the previous target position displacement, feedback-controls the drive current, and the elastic force is higher than the actuator suction force that sucks the movable yoke. The tactile presentation device according to claim 1, wherein the yoke gap distance is calibrated by specifying a displacement that does not satisfy a large condition. The control unit stores the yoke gap distance used when the vibration target is vibrated as the previous yoke gap distance, and the yoke gap distance measured by the measuring unit in the neutral state is used as the yoke gap distance this time. When the difference between the current yoke gap distance and the previous yoke gap distance is greater than or equal to a predetermined value, the current yoke gap distance is calibrated and generated in the fixed yoke when the vibration target is vibrated. The tactile presentation device according to claim 1 or 2, wherein the electromagnetic force is controlled by using the calibrated yoke gap distance this time. When the difference between the current yoke gap distance and the previous yoke gap distance is less than a predetermined value, the control unit does not calibrate the current yoke gap distance and causes the fixed yoke to vibrate the vibration target. The tactile presentation device according to claim 3, wherein the electromagnetic force generated in the above is controlled by using the previous yoke gap distance. A movable yoke (11) connected to a vibration target (3) and a fixed yoke (6) are provided, and an electromagnetic force is generated in the fixed yoke to attract the movable yoke to make the elastic member (12) elastic. A tactile presentation system including a plurality of tactile presentation devices that vibrate the vibrating object by force to present a tactile sensation.
A measuring unit (10) provided individually for the plurality of tactile presentation devices and measuring the yoke gap distance, which is the gap distance in the suction direction between the fixed yoke and the movable yoke,
Control that calibrates the yoke gap distance measured by the measuring unit in the neutral state and controls the electromagnetic force generated in the fixed yoke when vibrating the vibrating object by using the calibrated yoke gap distance. A tactile presentation system including a part (17). A movable yoke (11) connected to a vibration target (3) and a fixed yoke (6) are provided, and an electromagnetic force is generated in the fixed yoke to attract the movable yoke to make the elastic member (12) elastic. To the control unit (17) of the tactile sensation presenting device that vibrates the vibrating object by force to present the tactile sensation.
A calibration procedure for calibrating the yoke gap distance, which is the gap distance in the suction direction between the fixed yoke and the movable yoke in the neutral state, and
A computer program for executing an electromagnetic force control procedure for controlling an electromagnetic force generated in the fixed yoke when vibrating the vibrating object using the yoke gap distance calibrated by the calibration procedure. In the calibration procedure, the suction target position displacement of the movable yoke is set to be gradually larger than the previous target position displacement, the drive current is feedback-controlled, and the elastic force is higher than the actuator suction force that sucks the movable yoke. The computer program according to claim 6, wherein the yoke clearance distance is calibrated by identifying a displacement that does not satisfy a large condition. A computer-readable, non-temporary storage medium that stores the computer program according to claim 6 or 7.

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