Tactile detection device and tactile transmission system

Abstract

To enable detection of tactile sensations felt by fingertips or the like with a simple configuration.SOLUTION: A tactile detection device comprises: a piezoelectric sensor including a piezoelectric film that generates electric charges through deformation when pressure is applied; and a detection circuit that converts the electric charges generated by the piezoelectric sensor into the voltage. The piezoelectric sensor is disposed in direct or indirect contact with the skin surface, and on the skin surface, when an object is touched, the voltage converted from the electric charges generated by the piezoelectric sensor is used as a tactile detection signal. Further, the tactile detection signal is sampled at a predetermined frequency, and converted into a pulse voltage with a constant short interval for each sampling signal, the pulse voltage is then applied to an electrode in contact with the skin of a tactile presenter to present the tactile sensation.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a tactile detection device that digitizes the tactile sensation felt by a fingertip or the like, and a tactile transmission system that transmits the tactile data obtained by the tactile detection device.

Background Art

[0002] In recent years, tactile presentation devices that present a pseudo-tactile sensation to the skin of a finger or the like have been developed. For example, a tactile presentation device has been developed that reproduces various tactile sensations, such as the tactile sensation when a finger rubs against a smooth surface or the tactile sensation when a finger rubs against a rough surface, by vibrating a vibrating member attached to the finger. By using such a tactile presentation device, for example, tactile sensations linked to an image can be presented to give the subject a feeling as if they have actually touched what is shown in the image.

[0003] As a method of presenting tactile sensation, in addition to the method of physically vibrating a vibrating member, there is a method of applying a stimulus by an electrode. Since the electrode can be configured to be relatively small, it is suitable. Patent Document 1 describes a technique for presenting tactile sensation by bringing a minute electrode disposed on a substrate into contact with a finger and applying an electrical stimulus.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, as described in Patent Document 1, although the development of techniques for presenting tactile sensation to a fingertip or the like has progressed, it cannot be said that the technique for appropriately detecting and digitizing the tactile sensation itself felt by a human fingertip or the like has progressed. That is, when digitizing the tactile sensation felt by a fingertip, it is necessary to correctly detect the vibration of the fingertip corresponding to the tactile sensation with a sensor or the like. In order to accurately detect the vibration of the fingertip, it is necessary to attach a vibration detection sensor of a certain size to the fingertip for detection, and a relatively large-scale detection device is required.

[0006] If the vibration detection sensor attached to the fingertip or the like can be miniaturized, it becomes possible to easily detect the sense of touch and convert it into data. Then, if the vibration data corresponding to the obtained sense of touch is transmitted to a tactile presentation device described in Patent Document 1 or the like, the sense of touch felt by the tactile sensor in real time can be presented to another tactile presenter. However, such a tactile presentation device could not be realized by the conventional technology.

[0007] In view of such a point, an object of the present invention is to provide a tactile detection device capable of easily detecting a sense of touch, and a tactile transmission system for transmitting the tactile data obtained by the tactile detection device.

Means for Solving the Problems

[0008] The tactile detection device of the present invention includes a piezoelectric sensor provided with a piezoelectric film disposed on a base film, which generates charges when deformed by the application of pressure, and a detection circuit that converts the charges generated by the piezoelectric sensor into a voltage. And the tactile detection device of the present invention arranges the piezoelectric sensor in a state of being in contact with the skin surface, and in the vicinity of the skin surface, when touching an object, the charges generated in the piezoelectric sensor are converted into a voltage by the detection circuit to obtain a tactile detection signal.

[0009] In addition, the tactile transmission system of the present invention is a tactile transmission system that transmits the sense of touch felt by the tactile sensor through the skin to the tactile presenter. The tactile transmission system of the present invention includes a piezoelectric sensor equipped with a piezoelectric film that is worn in a state of being in direct or indirect contact with the skin surface of a tactile detector, and generates electric charges when deformed by the application of pressure, a detection unit that samples the tactile detection signal obtained by converting the electric charges generated by the piezoelectric sensor into a voltage at a predetermined frequency, a waveform processing unit that sets the signal sampled by the detection unit as a pulse voltage at a constant short time interval for each sampling signal, and a pulse application unit that applies the pulse voltage at a constant short time interval obtained by the waveform processing unit to an electrode in contact with the skin of the tactile presenter.

Advantages of the Invention

[0010] According to the present invention, the tactile sensation felt by the tactile detector can be detected with high precision by the piezoelectric sensor, and a tactile detection signal can be obtained. Furthermore, by sampling the obtained tactile detection signal and applying it to the electrode, the tactile sensation felt by the tactile detector can also be made to be felt by another tactile presenter.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0012] Hereinafter, an embodiment of the present invention (hereinafter referred to as "this example") will be described with reference to the accompanying drawings. As shown in FIG. 1, the tactile transmission system of this example includes tactile detection sensors 30a, 30b, 30c, 30d, 30e attached to five fingers of the hand H1 of the tactile detector, and electrodes 23a, 23b, 23c, 23d, 23e attached to five fingers of the hand H2 of the tactile presenter that presents the tactile sensation detected by the tactile detector. Then, the tactile sensations detected by the tactile detection sensors 30a, 30b, 30c, 30d, 30e are transmitted to the tactile presenter by the electrodes 23a, 23b, 23c, 23d, 23e and reproduced.

[0013] In addition, in FIG. 1, an example in which the tactile detection sensors 30a to 30e and the electrodes 23a to 23e are attached to all five fingers is shown, but the number of the tactile detection sensors 30a to 30e and the number of the electrodes 23a to 23e are just examples. For example, one tactile detection sensor 30a may be attached to one finger of the tactile detector, and the electrode 23a may be attached to one finger of the tactile presenter.

[0014] The tactile detection sensors 30a to 30e are piezoelectric sensors that detect electric charges according to tactile sensations, although the detailed configuration will be described later. The tactile detection sensors 30a to 30e are connected to the tactile transmission device 10. The tactile transmission device 10 processes the detection signals of the tactile detection sensors 30a to 30e and generates applied signals for the electrodes 23a, 23b, 23c, 23d, 23e.

[0015] In addition, as will be described below, the tactile transmission device 10 obtains tactile detection signals from the tactile detection sensors 30a to 30e and performs a tactile transmission process of generating signals to be applied to the electrodes 23a to 23e based on the tactile detection signals. Therefore, the tactile transmission device 10 can also be said to be a tactile detection device when viewed from the operation of performing tactile detection.

[0016] [Configuration of Tactile Transmission Device] The tactile transmission device 10 is configured by a computer, which is an information processing device for example, and includes an acquisition unit 11, a waveform processing unit 12, a storage unit 13, and a transmission unit 14. The acquisition unit 11 includes a detection unit 11a that converts the charge that changes according to the detection of the sense of touch by the tactile detection sensors 30a to 30e into a voltage signal. The voltage signal converted by the detection unit 11a in the acquisition unit 11 is a detection signal (tactile detection signal) of vibration corresponding to the sense of touch felt by the tactile detector. That is, the tactile detection sensors 30a to 30e detect the vibration of the finger when the finger of the tactile detector touches (rubs) the surface of an object, and obtain a tactile detection signal corresponding to the vibration.

[0017] For example, when the tactile detection sensors 30a to 30e perform an operation of rubbing an object with a rough (minutely uneven) surface at the location of the fingertip of the tactile detector, a detection signal due to the vibration of the finger corresponding to the roughness (minute unevenness) is obtained. The detection signal output by the tactile detection sensors 30a to 30e is a signal due to a change in charge, and in the detection unit 11a in the acquisition unit 11, a voltage detection signal (analog signal) corresponding to the vibration of the finger is obtained by a current / voltage conversion circuit (not shown).

[0018] Furthermore, in the acquisition unit 11, an analog signal that is a tactile detection signal is amplified by an amplifier (not shown), and then an acquisition process of digitizing and capturing it is performed. The tactile detection signal (digital signal) obtained by the acquisition unit 11 is supplied to the waveform processing unit 12.

[0019] The waveform processing unit 12 performs waveform processing of sampling the supplied digitized tactile detection signal at a relatively low frequency (for example, a frequency within the range of 20 Hz to 300 Hz) for tactile presentation. Note that the sampling frequency at the time of digitization in the acquisition unit 11 is set to a frequency higher than the sampling frequency at the time of conversion to a burst wave in the waveform processing unit 12, or is set to the same frequency as the sampling frequency at the time of conversion to a burst wave in the waveform processing unit 12.

[0020] Furthermore, the waveform processing unit 12 ensures that each sampling value of the sampled data is maintained for a relatively short time. The short time for applying voltage here, that is, the on-pulse width, is, for example, from 0.1 milliseconds to 0.3 milliseconds. Also, the interval between each sampling signal (pulse signal) between the on-pulse width and the next on-pulse width, that is, the off-pulse width, is set to 0.2 milliseconds or more. Thereby, processing is performed to form pulses at a constant short time interval for each sampling signal.

[0021] The tactile detection signal (tactile detection data) obtained by the processing of the waveform processing unit 12 is once stored in the storage unit 13, and then transmitted from the transmission unit 14 to the pulse application device 20 by wire or wirelessly. Note that the transmission unit 14 may transmit the outputs of the tactile detection sensors 30a to 30e processed by the waveform processing unit 12 in real time.

[0022] Also, as shown in FIG. 1, the pulse application device 20 includes a reception unit 21 and a pulse application unit 22. The reception unit 21 receives the tactile detection signal (tactile detection data) transmitted from the tactile transmission device 10. When performing wireless transmission between the transmission unit 14 of the tactile transmission device 10 and the reception unit 21 of the pulse application device 20, for example, wireless communication is performed according to the Bluetooth (registered trademark) standard. The tactile detection signal received by the reception unit 21 is supplied to the pulse application unit 22.

[0023] The pulse application unit 22 applies a pulse voltage to the electrodes 23a, 23b, 23c, 23d, and 23e attached to the five fingers of the hand H2 of the tactile presenter. The surfaces of the skins of the five fingertips of the hand H2 of the tactile presenter are in contact with the respective electrodes 23a, 23b, 23c, 23d, and 23e. Also, although not shown, the ground potential unit is also brought into contact with the surface of the skin of the same finger.

[0024] Then, the pulse application unit 22 applies the tactile detection signal received by the reception unit 21 to each of the electrodes 23a, 23b, 23c, 23d, and 23e. Here, the received tactile detection signal is a pulse signal with a pulse width of on from 0.1 milliseconds to 0.3 milliseconds at a frequency within the range of 20 Hz to 300 Hz. Note that the interval between each off pulse signal is 0.2 milliseconds or more.

[0025] When data specifying the finger that gives the tactile sensation is added to the tactile detection signal (tactile detection data) supplied from the pulse application unit 22 to each of the electrodes 23a, 23b, 23c, 23d, and 23e, among the five electrodes 23a, 23b, 23c, 23d, and 23e, a pulse signal is applied to any one of the electrodes attached to the corresponding finger.

[0026] Note that the tactile transmission device 10 shown in FIG. 1 is composed of a computer, which is a so-called information processing device. That is, when the hardware configuration of the computer as the tactile transmission device 10 is shown below FIG. 1, the tactile transmission device 10 includes a CPU (Central Processing Unit) 10a, a work memory 10b, a storage 10c, an input unit 10d, and a communication interface 10e.

[0027] The CPU 10a is an arithmetic processing unit that reads the program code of the software that realizes the functions performed by the tactile transmission device 10 from the storage 10c and causes the work memory 10b to execute it. By the CPU 10a reading the program code from the storage 10c and executing arithmetic processing in the work memory 10b, various processing functional units are configured in the work memory 10b. For example, the acquisition unit 11 and the waveform processing unit 12 described above are configured in the work memory 10b.

[0028] The storage 10c stores program data and also stores tactile detection signals. The input unit 10d performs input processing of tactile detection signals from the tactile detection sensors 30a to 30e. The communication interface 10e communicates with the pulse application device 20.

[0029] [Configuration Example of Tactile Detection Sensor] FIG. 2 shows a configuration example of the tactile detection sensors 30a to 30e in this example. In FIG. 2, the configuration of the tactile detection sensor 30a is shown, but the other tactile detection sensors 30b to 30e also have the same configuration as the tactile detection sensor 30a.

[0030] FIG. 2A shows the cross-sectional configuration of the tactile detection sensor 30a, FIG. 2B shows the layers of the tactile detection sensor 30a disassembled, and FIG. 2B shows the configuration as viewed from above. As shown in FIG. 2, the tactile detection sensor 30a includes a first electrode 31, an FPC (Flexible printed circuits) 32, a second electrode 33, a piezoelectric film 34, and a conductive thin film member 35. The tactile detection sensor 30a having the configuration described below can be, for example, one called Picoleaf (trade name: registered trademark).

[0031] The first electrode 31 and the second electrode 33 are respectively formed on both main surfaces of the FPC 32 in advance. The second electrode 33 functions as a shield conductor. Although not shown in FIG. 2, the conductive thin film member 35 and the second electrode 33 are patterned on the lower surface side of the FPC 32 so as not to be short-circuited and to be electrically connected to the third electrode 36 shown in FIG. 2B. Further, for example, the piezoelectric film 34 and the FPC 32 are attached with an adhesive sheet or the like.

[0032] The FPC 32 is an insulating base material having flexibility such as polyimide, PET, or liquid crystal polymer. The second electrode 33 is formed on the lower surface side of the FPC 32. The first electrode 31 is formed on the upper surface side of the FPC 32. The first electrode 31 functions as a signal electrode for detecting the charge generated in the piezoelectric film 34. The first electrode 31 extends along the longitudinal direction of the FPC 32 and is electrically connected to a detection terminal portion (not shown). The first electrode 31 and the conductive thin film member 35 are also connected to the ground portion of the detection terminal portion.

[0033] On the upper surface of the first electrode 31, the lower surface of the piezoelectric film 34 is attached. Also, on the upper surface of the piezoelectric film 34, a conductive thin film member 35 is attached. The conductive thin film member 35 is electrically connected to a third electrode 36 (FIG. 2B) formed on the upper surface of the FPC 32. The third electrode 36 extends along the longitudinal direction of the FPC 32 and is electrically connected to the detection element 37. The detection element 37 performs processing to obtain a voltage signal corresponding to the change in charge obtained by the piezoelectric film 34 and constitutes a part of the detection unit 11a. Note that the detection element 37 may not be attached to the tactile detection sensor 30a, and the first electrode 31 and the second electrode 33 may be drawn out to the outside.

[0034] Thereby, the conductive thin film member 35 functions as a shield conductor. Also, according to such a structure, both the signal electrode and the ground electrode can be taken out from the upper surface (the same surface) of the same FPC 32, facilitating mounting. The upper surface of the conductive thin film member 35 is preferably further covered and protected with a PET film or the like. Alternatively, a configuration may be adopted in which no protective film is provided on the upper surface of the conductive thin film member 35.

[0035] As the conductive thin film member 35, for example, a conductive nonwoven fabric with an adhesive formed thereon or a copper foil impregnated with resin with an adhesive formed thereon is used. The conductive thin film member 35 is attached so as to cover the piezoelectric film 34 and also cover the third electrode 36. However, the conductive thin film member 35 does not necessarily have to cover all of them, and it is sufficient if it covers at least a part. The conductive thin film member 35 has a lower rigidity than the first electrode 31 and the second electrode 33 so as not to inhibit the deformation of the piezoelectric film.

[0036] For example, when the first electrode 31 and the second electrode 33 are made of a copper foil with an elastic modulus of about 1.0×109 Pa and the conductive thin film member 35 is made of a conductive non-woven fabric with an elastic modulus of about 1.0×105 Pa to 1.0×106 Pa, the deformation due to pressing is easily transmitted to the piezoelectric film 34, and the deformation of the piezoelectric film 34 is not inhibited. Also, even when the conductive thin film member 35, the first electrode 31, and the second electrode 33 are made of the same material, by making the thickness of the conductive thin film member 35 thinner than the thicknesses of the first electrode 31 and the second electrode 33, the deformation of the piezoelectric film 34 is not inhibited.

[0037] The piezoelectric film 34 is a piezoelectric material that generates charges on the opposing flat film surfaces by expansion and contraction, and a chiral polymer is used. More preferably, the piezoelectric film 34 uses uniaxially stretched polylactic acid (PLA), and more specifically, L-type polylactic acid (PLLA). The uniaxial stretching direction of the polylactic acid forms an angle of approximately 45° with respect to the longitudinal direction of the piezoelectric film. Note that the most preferable angle is 45°, but it may be within a range of ±10°.

[0038] The chiral polymer has a helical structure in the main chain and has piezoelectricity when uniaxially stretched and the molecules are oriented. Since the chiral polymer generates piezoelectricity through molecular orientation treatment such as stretching, there is no need to perform a poling treatment like other polymers such as PVDF or piezoelectric ceramics. In particular, polylactic acid has no pyroelectricity, so even when heat from the user's finger or the like is transmitted, the amount of detected charge does not change. Also, the piezoelectric constant of uniaxially stretched PLLA belongs to a very high category among polymers. For example, the piezoelectric strain constant d14 of PLLA can obtain a high value of 10 to 20 pC / N by adjusting conditions such as stretching conditions, heat treatment conditions, and the blending of additives. Furthermore, the piezoelectric constant of PLLA does not vary over time and is extremely stable.

[0039] Note that the stretching ratio of the piezoelectric film is preferably about 3 to 8 times. By performing heat treatment after stretching, the crystallization of the stretched and broken chain crystals of polylactic acid is promoted, and the piezoelectric constant is improved. When biaxially stretching, the same effect as uniaxial stretching can be obtained by making the stretching ratios of the respective axes different. For example, when stretching 8 times in a certain direction as the X axis and 2 times in the Y axis direction orthogonal to that axis, the effect on the piezoelectric constant is almost the same as that when performing uniaxial stretching 4 times in the X axis direction. Since a simply uniaxially stretched piezoelectric film is liable to tear along the stretching axis direction, the strength can be increased somewhat by performing biaxial stretching as described above. Using the piezoelectric film 34 as a chiral polymer (polylactic acid) is just an example, and for example, it is also feasible with PVDF.

[0040] The signal electrode and the ground electrode of the tactile detection sensor 30a configured in this way are connected to the acquisition unit 11 of the tactile transmission device 10 shown in FIG. 1. In the example of FIG. 2, the FPC 32 as the base film is configured in a strip shape, and the strip-shaped FPC 32 is connected in a ring shape. Thereby, the tactile detection sensor 30a has a ring shape and can be worn on the finger of the hand H1 of the tactile detector. When worn on the finger of the hand H1, the conductive thin film member 35 on the piezoelectric film 34 is in a state of contacting the skin surface of the finger. When a protective film is provided on the surface of the conductive thin film member 35, the conductive thin film member 35 is in a state of indirectly contacting the skin surface of the finger. Such a tactile detection sensor 30a using the piezoelectric film 34 is very sensitive and can detect pressure (pushing), and can detect a minute displacement in units of, for example, 1 μm. In addition, the tactile detection sensor 30a using the piezoelectric film 34 has no sensitivity variation due to temperature (the body temperature of the wearer) and generates little noise.

[0041] [Example of Transmission Processing of Tactile Detection Signal] FIG. 3 is a flowchart showing an example of processing in the tactile transmission device 10 and the pulse application device 20. First, the tactile transmission device 10 samples the input tactile detection signal (voltage signal) as pulse data sampled at a low frequency for tactile presentation within the range of 20 Hz to 300 Hz, and performs waveform processing such that each on-pulse width is from 0.1 ms to 0.3 ms (step S11). Here, the off-pulse width is set to 0.2 ms or more. Then, the transmission unit 14 transmits the tactile presentation data obtained in step S11 to the pulse application device 20 (step S12). The tactile transmission device 10 repeatedly executes the processes of steps S11 and S12.

[0042] The pulse application device 20 receives the tactile presentation data transmitted in step S21 (step S21). Then, the pulse application unit 22 applies a pulse voltage corresponding to the tactile presentation data received in step S21 to any one of the finger electrodes 23a to 23e (step S22). The pulse application device 20 repeatedly executes the processes of steps S21 and S22.

[0043] [Examples of Sensor Detection Signals and Electrode Application Signals] Next, examples of the sensor detection signal supplied to the tactile transmission device 10 in this example and the tactile presentation signal obtained by processing the sensor detection signal will be described. FIG. 4 is an enlarged view showing a part of the tactile detection signal (analog signal) supplied from the tactile detection sensors 30a to 30e to the acquisition unit 11 of the tactile transmission device 10. The horizontal axis in FIG. 4 is time, and the vertical axis is a physical quantity corresponding to the vibration state for touch, for example, voltage.

[0044] As shown in FIG. 4, the tactile detection signal supplied to the acquisition unit 11 has the characteristic α of a curve corresponding to the vibration state indicating touch. The variation in the physical quantity of this characteristic α corresponds to the touch obtained from the locations touched by the tactile detection sensors 30a to 30e.

[0045] FIG. 5 shows the time change of the tactile presentation data obtained when the tactile detection signal shown in FIG. 4 is processed by the tactile transmission device 10 in this example. The horizontal axis in FIG. 5 is time, and the vertical axis is the physical quantity (voltage) applied to the electrode. As already described, the waveform processing unit 12 of the tactile transmission device 10 performs processing to obtain a pulse signal with an on-pulse width between 0.1 ms and 0.3 ms at a specific frequency (period) within the range of 20 Hz to 300 Hz. As a result, as shown in FIG. 5, pulse signals P1, P2, P3, ··· in which the signal values at each timing of the tactile detection signal are sampled are obtained.

[0046] The pulse values (peak values) of the respective pulse signals P1, P2, P3, ··· shown in FIG. 5 are values obtained by sampling the tactile detection signal shown in FIG. 4 and change according to the detection state of the touch. Here, the on-pulse width PW is a value set between 0.1 ms and 0.3 ms, and all the pulse signals P1, P2, P3, ··· have the same pulse width value. Also, the off-pulse width set to 0.2 ms or more is the same value for all intervals of the pulse signals P1, P2, P3, ···. The tactile transmission device 10 outputs such pulse signals P1, P2, P3, ··· with the on-pulse width PW, which are applied from the pulse application device 20 to the electrodes 23a, 23b, 23c, 23d, 23e.

[0047] Thereby, the tactile transmission device 10 can present to the finger of the tactile presenter wearing the electrodes 23a to 23e the same touch as the touch detected by the tactile detection sensors 30a to 30e. In this case, each of the pulse signals P1, P2, P3, ··· is a signal generated at intervals set to 0.2 ms or more. Then, the tactile presenter wearing the electrodes 23a to 23e can appropriately feel the electrical stimulation from the tactile transmission device 10 as the touch of the finger.

[0048] If a pulse signal with a relatively large interval as in this example is not used, there is a possibility that the tactile presenter may feel pain when the voltage signal is applied. However, in the case of this example, it is possible to avoid giving such pain and only give a good touch to the tactile presenter.

[0049] [Examples of sensor signals when rubbing the surfaces of various objects] In the examples of FIGS. 4 and 5, a very simple tactile detection signal is shown. However, in the tactile transmission device 10 of this example, it is possible to detect and transmit a tactile sensation corresponding to various tactile detection signals. FIG. 6 shows examples of tactile detection signals output by the tactile detection sensors 30a to 30e when a tactile detector rubs the surfaces of five types of objects. The horizontal axis in FIG. 6 represents time (seconds), and the vertical axis represents a physical quantity (voltage: mV). Here, an example of acquiring data for 2 seconds is shown.

[0050] As the respective data d1, d2, d3, d4, and d5 shown in FIG. 6, examples of data when rubbing with a finger are shown below. Data d1 is a tactile detection signal when rubbing the surface of a plastic corrugated board (so-called plastic corrugated) having a structure similar to that of cardboard with a finger. Data d2 is a tactile detection signal when rubbing the surface of a relatively smooth wallpaper with a finger. Data d3 is a tactile detection signal when rubbing the surface of a hook-and-loop fastener (trade name Magic Tape: registered trademark) with a finger. Data d4 is a tactile detection signal when rubbing the surface of a silicone sheet with a finger. Data d5 is a tactile detection signal when rubbing the surface of an aluminum sheet with a finger.

[0051] As can be seen by comparing the data d1 to d5 shown in FIG. 6, the vibration states detected by the tactile detection sensors 30a to 30e change according to the surface states of the respective materials. Although the respective data d1 to d5 shown in FIG. 6 are analog waveforms, the waveform processing unit 12 of the tactile transmission device 10 in this example samples each of the data d1 to d5 at a specific period (for example, sampling at 200 Hz) and applies them as pulse signals at intervals set to 0.2 msec or more to the electrodes 23a to 23e of the finger of the tactile presenter. Thereby, it is possible to give a tactile sensation similar to the tactile sensation when rubbing the surface of each material to the finger of the tactile presenter who is not touching the object.

[0052] [Another example of electrodes] Note that, as shown in Fig. 1, when the ring-shaped electrodes 23a to 23e are worn on the finger, since the electrodes are present on the fingertips of the finger on which the electrodes 23a to 23e are worn, the electrodes may get in the way when the tactile presenter rubs the surface of an object with the finger. Therefore, each of the electrodes 23a to 23e may be in a mounting state different from the example shown in Fig. 1. For example, as shown in Fig. 7, the electrodes 23x and 23y may be attached to positions close to the nails of the fingers F1 and F2 (the proximal side of the nails).

[0053] The positions where the electrodes 23x and 23y are attached are the proximal sides of the nails of the fingers F1 and F2 as shown in Fig. 7, and since the attached electrodes 23x and 23y do not get in the way, the tactile presenter can touch the surface of the object and feel the touch. Also, even when the electrodes 23x and 23y are attached in the state shown in Fig. 7, the tactile presenter can feel the touch at the fingertips in the same manner as in the case of the ring electrodes as shown in Fig. 1, by the pulse signal applied.

[0054] Also, the point of attaching the tactile detection sensors 30a to 30e to the fingertips to present the touch as shown in Fig. 1 is merely an example. The tactile detector may attach the tactile detection sensors 30a to 30e to other parts of the human skin, and the tactile presenter may attach electrodes to substantially the same parts to detect and present the touch. Note that, in the configuration shown in Fig. 1, the tactile transmission device 10 and the pulse application device 20 are configured as separate devices. In contrast, for example, the tactile transmission device 10 and the pulse application device 20 may be integrated. In this case, for example, by miniaturizing the integrated tactile transmission device and making it wearable on the wrist or the like of the tactile presenter, the touch can be presented to the fingertips more simply.

[0055] Also, in the configuration shown in Fig. 1, the tactile transmission device 10 is configured to process the tactile detection signals output by the tactile detection sensors 30a to 30e. However, the tactile detection signals output by the tactile detection sensors 30a to 30e may only perform the tactile detection process of storing in the storage unit 13, and the storage unit 13 may read out the past tactile detection signals stored at an arbitrary timing and apply the same pulse signals to the electrodes 23a to 23e.

[0056] As a result, for example, when rubbing the surfaces of a plurality of types of objects as shown in FIG. 6, the memory unit 13 can memorize the tactile sensations, and can freely present the selected tactile sensation to the fingertips of the tactile sensation presenter according to the situation at that time.

[0057] Note that as the signal memorized by the memory unit 13, it is preferable to memorize, for example, a pulse signal subjected to waveform processing as shown in FIG. 5. Thereby, the tactile sensation transmission device 10 can read out the stored data of the memory unit 13 and can be directly applied to the electrodes without performing waveform processing.

[0058] In addition, in FIG. 1, the tactile sensation transmission device 10 is illustrated as an example configured by a computer which is an information processing device. On the other hand, the tactile sensation transmission device 10 and the pulse application device 20 may be configured as devices provided with dedicated hardware for performing respective signal processing. When configuring the tactile sensation transmission device 10 as a computer, a program for executing the processing procedure described in the flowchart of FIG. 2 may be prepared, installed in the tactile sensation transmission device 10 which is a computer, and executed by the tactile sensation transmission device 10.

Explanation of Reference Numerals

[0059] 10... Tactile sensation transmission device, 10a... CPU, 10b... Work memory, 10c... Storage, 10d... Input unit, 10e... Communication interface, 11... Acquisition unit, 11a... Detection unit, 12... Waveform processing unit, 13... Memory unit, 14... Transmission unit, 20... Pulse application device, 21... Reception unit, 22... Pulse application unit, 23a, 23b, 23c, 23d, 23e, 23x, 23y... Electrodes, 30a, 30b, 30c, 30d, 30e... Tactile sensation detection sensors, 31... First electrode, 32... FPC (Flexible printed circuits), 33... Second electrode, 34... Piezoelectric film, 35... Conductive thin film member, 36... Third electrode, 37... Detection element

Claims

1. A piezoelectric sensor including a piezoelectric film disposed on a base film that generates electric charges when deformed by an applied pressure, and a detection circuit that converts the electric charges generated by the piezoelectric sensor into a voltage, wherein the piezoelectric sensor is disposed in direct or indirect contact with the skin surface, and when an object is touched on the skin surface, the electric charges generated in the piezoelectric sensor are converted into a voltage by the detection circuit to obtain a tactile detection signal. A tactile detection device.

2. wherein the skin surface is a human skin surface, the base film of the piezoelectric sensor has a shape that can be attached to or installed on the skin surface, and the tactile detection signal is a detection signal of the tactile sensation felt on the skin surface. The tactile detection device according to Claim 1.

3. A tactile transmission system that transmits the tactile sensation felt by a tactile sensor using the skin to a tactile presenter, including a piezoelectric sensor that is worn in a state of being in direct or indirect contact with the skin surface of the tactile sensor and generates electric charges when deformed by an applied pressure, a detection unit that samples the tactile detection signal obtained by converting the electric charges generated by the piezoelectric sensor into a voltage at a predetermined frequency, a waveform processing unit that converts the signal sampled by the detection unit into a pulse voltage with a constant short time interval for each sampling signal, and a pulse application unit that applies the pulse voltage with the constant short time interval obtained by the waveform processing unit to an electrode in contact with the skin of the tactile presenter. A tactile transmission system.

4. wherein the predetermined frequency is a frequency between 20 Hz and 300 Hz, the pulse width of the on-state of the pulse voltage with a short time width is set between 0.1 ms and 0.3 ms, and the pulse width of the off-state of each pulse voltage is 0.2 ms or more. The tactile transmission system according to Claim 3.

5. wherein the piezoelectric sensor is worn on the finger of the tactile sensor, the electrode is worn on the finger of the tactile presenter, and the tactile sensation felt by the finger of the tactile sensor is transmitted to the finger of the tactile presenter. The tactile transmission system according to Claim 3.

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