JP4291830B2 - Tactile information transmission device using mechanical vibration of shape memory alloy as information transmission means - Google Patents

Description

  The present invention relates to an information transmission device that transmits tactile information to a living body using a shape memory alloy.

2. Description of the Related Art Conventionally, information transmission apparatuses that transmit information by using a vibration motor, a piezoelectric element, or the like as a vibration source and stimulating the sense of touch of a human body are known. Further, for example, as disclosed in Patent Document 1, a shape memory alloy and an elastic body are provided, and heating by energization of the shape memory alloy itself, heating by a heating element installed along the shape memory alloy, or laser light irradiation 2. Description of the Related Art There is known an information transmission device that transmits information to the tactile sensation of a human body by deforming a shape memory alloy by a phase change by heating or the like, and returning to an original shape by the elasticity of an elastic body by cooling. In addition, for example, as shown in Patent Document 2, a heat source is provided in the vicinity of the shape memory alloy, and the expansion and contraction of the shape memory alloy is controlled by controlling the voltage and current values to the heat source. Devices for performing are known.
JP 11-219143 A JP-A-11-203040

  However, in a conventional information transmission device using a vibration motor, the size of the mechanical vibration part is large, so information cannot be transmitted to a minute tactile part such as a part of a finger, and information is transmitted to a plurality of locations. When a plurality of vibration motors are driven, vibrations interfere with each other, and it is difficult to transmit detailed information to a plurality of adjacent locations. In addition, it cannot vibrate at a high frequency and has poor energy efficiency. In an information transmission device using a piezoelectric element, information cannot be sufficiently transmitted because the amount of displacement is small.

  Further, in the tactile force sense presentation device as shown in Patent Document 1, information is transmitted by the shape change of the shape memory alloy, but such a shape change has a slow response and it is difficult to exhibit a vibration phenomenon. It is not enough for information transmission.

  Further, in the tactile force sense presentation device as shown in Patent Document 2, since the shape memory alloy is heated by a heat source, it takes time for heating and cooling, and it is impossible to exhibit a vibration phenomenon as described above. is there.

  The present invention solves the above-described problems, can exhibit a vibration phenomenon with good responsiveness, is small and lightweight, has high energy efficiency, and can transmit advanced information such as character information to a living body. An object is to provide an information transmission device.

In order to achieve the above object, an invention according to claim 1 is directed to an information transmission apparatus for a living body using a shape memory alloy, and a shape memory alloy main body and an on / off duty for signal transmission to the shape memory alloy main body. And a pulse generator for applying a pulse voltage of the same or different peak value, the shape memory alloy body is bent into a horseshoe shape and fixed at both ends, and the middle part of the alloy body contacts the living body It is configured such that mechanical vibration is generated by repeating the change of the length of the horseshoe-shaped portion of the alloy body by applying the pulse voltage, and information can be transmitted to the tactile sense of a living body. is there.

According to a second aspect of the present invention , in the information transmission device to a living body according to the first aspect, a plurality of the shape memory alloy main bodies are linearly or planarly or three-dimensionally arranged, and the pulse generator When simultaneously applying a pulse voltage to a plurality of adjacent shape memory alloy bodies, applying a pulse voltage having at least one peak value different before and after the passage of time, and applying a pulse voltage having the same peak value, By applying a pulse voltage with a time difference to one to the other, a living body in contact with the alloy body is given a feeling that an object has moved between the adjacent alloy bodies .

  According to the invention of claim 1, mechanical vibration is generated in the shape memory alloy main body by applying a pulse voltage, the intermediate portion of the horseshoe shape of the alloy is touched to the living body, and information is transmitted to the tactile sense of the living body. it can. As a result, it is small and light, efficient, and exhibits a vibration phenomenon, so that advanced information can be sufficiently transmitted to the living body.

  According to the invention of claim 2, by applying a pulse voltage with a time difference to a plurality of adjacent shape memory alloy main bodies, a sense of tactile movement can be given to the living body, for example, character information can be transmitted. It becomes.

(First embodiment)
An information transmission apparatus according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a configuration of an information transmission apparatus according to the present embodiment. The information transmission apparatus according to the present embodiment includes a small vibration actuator 1 that performs vibration motion, a pulse generator 2 that generates a pulse voltage that causes the small vibration actuator 1 to perform vibration motion, and a pulse voltage generated by the pulse generator 2. And a voltage amplifier 3. FIG. 2 shows a configuration of the small vibration actuator 1 provided in the information transmission apparatus according to the present embodiment. The small vibration actuator 1 includes two lead wire portions 4, an insulating portion 5 that fixes the lead wire portion 4, and a shape memory alloy that is bent and connected to the tips of the two lead wire portions 4 in a horseshoe shape. A main body 6 is provided. The insulating part 5 has a diameter of 5 mm. The shape memory alloy body 6 is formed by bending a shape memory alloy having a diameter of 50 μm, a length of 5 mm, and a resistance value of 2Ω. The shape memory alloy main body 6 only needs to have a strength that does not impair the robustness. Then, the shape memory alloy main body 6 generates heat due to its own resistance and rises in temperature.

  Next, the operation of the information transmission apparatus configured as described above will be described. The pulse generator 2 generates a pulse wave that vibrates the shape memory alloy body 6 of the small vibration actuator 1, and the voltage amplifier 3 amplifies the pulse wave to a predetermined voltage. The amplified pulse wave is energized to the shape memory alloy body 6 via the lead wire portion 4. The operation of the shape memory alloy body 6 when a pulse wave is applied to the shape memory alloy body 6 will be described with reference to FIG. FIG. 3 shows the relationship between the temperature and length of the shape memory alloy body 6. The horizontal axis indicates the temperature of the shape memory alloy main body 6, and the vertical axis indicates the length of the shape memory alloy main body 6. Since the shape memory alloy body 6 has a resistance value, it generates heat when a voltage is applied, and contracts by 7% when the temperature is equal to or higher than the temperature T2, and is 0.93L from the original length L. Becomes shorter. When no voltage is applied, the heat is dissipated, and when the voltage is cooled to a temperature T1 or lower, the original length L is restored. And while the heating above the temperature T2 and the cooling below the temperature T1 are repeated by the application of the pulse wave, the length of the shape memory alloy body 6 repeats the change to the length L and the length 0.93L, The shape memory alloy body 6 vibrates.

  Next, a method of applying a pulse wave that vibrates the small vibration actuator 1 will be described with reference to FIG. FIG. 4 shows a state of applying a pulse wave. The horizontal axis indicates time, and the vertical axis indicates voltage. FIG. 4A shows the ratio of the on time and off time of the pulse wave. The shape memory alloy main body 6 requires a cooling time since it cannot be reheated and contracted unless it is radiated and cooled once it is heated and contracted. The on / off duty, which is the ratio of the voltage application time during which the shape memory alloy body 6 is heated and the voltage non-application time during which the shape memory alloy body 6 is cooled, is effectively about 1:20 when the applied voltage is 1V. If the voltage non-application time is shorter than this, cooling is insufficient and vibration does not occur. When the voltage application time in FIG. 4A is 1 to 100 ms, the voltage non-application time is 20 to 2000 ms.

  FIG. 4B shows a voltage application method when preheating the shape memory alloy body 6. When 0.3 V is applied as an offset voltage, the shape memory alloy body 6 is preheated, and the peak value of the pulse wave can be lowered to vibrate the shape memory alloy body 6.

  FIG. 4C shows a voltage application method in which the peak value of the pulse wave is changed. The peak values are changed to 1V, 1.2V, 0.5V, 1.5V, 0.7V, and 1.2V. When the crest value is low, the shape memory alloy main body 6 vibrates weakly, and when the crest value is high, the shape memory alloy main body 6 vibrates strongly. By changing the height of the peak value, the strength of vibration of the shape memory alloy main body 6 can be adjusted.

  FIG. 4D shows a voltage application method in which when applying a pulse wave intermittently, the time for applying the pulse wave is made constant and the interval for applying the pulse wave is changed. The time for applying the pulse wave is a constant time between 10 ms and 500 ms, and the interval time for applying the pulse wave is changed between 10 ms and 1 s. When the interval time is short, the stimulus given to the living body becomes strong, and when the interval time is long, the stimulus given to the living body becomes weak. The stimulus given to the living body can be adjusted by changing the interval time for applying the pulse wave.

  FIG. 4E shows a voltage application method in which, when a pulse wave is applied intermittently, the interval at which the pulse wave is applied is constant and the time for applying the pulse wave is changed. The interval time for applying the pulse wave is a constant time between 10 ms and 1 s, and the time for applying the pulse wave is changed between 1 ms and 50 ms. When the application time is long, the stimulus given to the living body becomes strong, and when the application time is short, the stimulus given to the living body becomes weak. The stimulus given to the living body can be adjusted by changing the time for applying the pulse wave.

  By applying a pulse wave to the shape memory alloy body 6 as described above, the shape memory alloy body 6 can be vibrated, and information can be transmitted to the sense of touch of the living body. Since the shape of the shape memory alloy main body 6 is a horseshoe shape, information can be better transmitted to the tactile sensation by arranging the shape memory alloy body 6 so that the apex of the shape memory alloy main body 6 touches the part where the human body senses the tactile sensation. Moreover, since the small vibration actuator 1 can be made small, it is possible to stimulate a very small portion. When the small vibration actuator 1 is attached to the hand, the middle finger, the base of the little finger, the tip of the index finger, etc. have been confirmed as sensitive parts, so that they may be placed on the part with emphasis. Also, in terms of safety, the voltage applied to the shape memory alloy body 6 is as low as several volts, does not particularly require insulation, and the temperature does not rise so much, so there is no need to pay particular attention to the temperature.

  The information transmission device using mechanical vibration of the small vibration actuator 1 according to the present embodiment as information transmission hand throw is small and light, has high energy efficiency, can respond to high frequencies, and has a very high resolution of the vibration source. In addition, if a vibration of about 0.5 Hz is given alone, it can be felt like a human pulse, and if a vibration of 10 to 200 Hz is applied, it can give a crisp touch.

  The small vibration actuator 1 has various uses. For example, the small vibration actuator 1 may be used alone when it is arranged on a cane used by a person and a signal is transmitted to the cane, or when it is attached to a dog collar. The frequency is good at about 1 Hz. If the frequency is higher than this, the living body is uncomfortable, and if it is lower, it is difficult to recognize. The on / off duty may be 1:20. When the on ratio is smaller than this, the living body is difficult to recognize, and when it is larger than this, vibration does not continue. It is also possible to transmit advanced information by vibration by combining a plurality of small vibration actuators 1 instead of a single unit. It can also be used for pulse generators for medical education, mobile phone information transmission, information transmission for the handicapped, and amusement. Further, the connection between the shape memory alloy main body 6 and the lead wire portion 4 may be in another form different from the present embodiment. The shape memory alloy body 6 is connected to the lead wire portion 4 at one end and an intermediate portion thereof, the other end of the shape memory alloy body 6 not connected to the lead wire portion 4 is used as a free end, and the free end is brought into contact with a living body. Vibrate. Since the amplitude width of the free end is increased, information can be transmitted to the tactile sense better.

(Second Embodiment)
An information transmission apparatus according to a second embodiment of the present invention will be described with reference to FIG. The information transmission device according to the present embodiment provides information to a living body using a plurality of small vibration actuators 1 of the information transmission device according to the first embodiment. FIG. 5 shows the configuration of the information transmission apparatus according to the present embodiment. The information transmission device according to the present embodiment has a shape of a gripping rod 21, and connects a plurality of small vibration actuators 1, a drive amplifier 22 that drives the small vibration actuator 1, and the small vibration actuator 1 and the drive amplifier. Wiring 23 is provided. The small vibration actuator 1 is attached to the grip bar 21 so that the shape memory alloy main body 6 contacts the belly of the fingertip, which is a sensitive part of the palm tactile sensation when the grip bar 21 is gripped. At this time, when an electrical signal at 0.1 Hz to 1 kHz is applied to the shape memory alloy body 6 via the drive amplifier 22, mechanical vibration is generated, and the vibration is transmitted to the palm portion in contact with the shape memory alloy body 6. The Furthermore, when the strength of an electric signal and its period are changed in time series, and applied as, for example, a PWAM wave, a combination of various mechanical vibrations can be experienced in time series on the part of the human body in contact with the shape memory alloy 22. it can. If some meaning is given in advance to the mechanical vibration intensity, cycle, and combination, it is transmitted as information having a complicated meaning.

(Third embodiment)
An information transmission apparatus according to a third embodiment of the present invention will be described with reference to FIG. The information transmission device according to the present embodiment transmits information to the back of the human body by the small vibration actuator 1 of the information transmission device according to the first embodiment. FIG. 6 shows the configuration of the information transmission apparatus according to this embodiment. The information transmission apparatus according to the present embodiment includes a plurality of small vibration actuators 1, a drive amplifier 22 that drives the small vibration actuator 1, and a wiring 23 that connects the small vibration actuator 1 and the drive amplifier. The shape memory alloy main body 6 according to this embodiment is a thin plate formed into a horseshoe shape. When the shape memory alloy body 6 is attached to the entire back of the human body and an electric signal is applied via the drive amplifier 22 as in the second embodiment, complicated information can be transmitted to the back. It should be noted that a structure in which a plurality of thin plates are appropriately pasted to a daily life device such as a chair back, a cane, a mobile phone, etc., which is not directly stuck to the human body but is touched by a sensitive part of the human body. You can also.

(Fourth embodiment)
An information transmission apparatus according to a fourth embodiment of the present invention will be described with reference to FIGS. 7 (a), 8 and 9. FIG. The information transmission device according to the present embodiment gives a tactile dynamic sensation to a living body by using a plurality of small vibration actuators 1 of the information transmission device according to the first embodiment. FIG. 7A shows the configuration of the information transmission apparatus according to the present embodiment. The information transmission apparatus according to the present embodiment includes a plurality of small vibration actuators 1, a multi-pulse generator 7 that generates a pulse voltage to be applied to the small vibration actuator 1, and a multi-voltage amplifier 8 that amplifies the pulse voltage. ing. The plurality of small vibration actuators 1 are arranged in a plane in a plurality of rows, and are arranged so that each shape memory alloy body 6 touches the living body. Since each of the shape memory alloy bodies 6 is connected to the multi-voltage amplifier 8 and individually applied with a pulse wave, the shape memory alloy body of the small vibration actuator 1 at any location covered by the information transmission device. 6 can be vibrated to give information to the living body.

  The arrangement position of the small vibration actuator 1 in FIG. 7A is indicated by coordinates, the position of the L point is (0, 0), and (1, 0) (2, 0) in order from the L point in the direction of the arrow X To do. Further, it is assumed that (0, 1) (0, 2) in order from the point L in the arrow Y direction. When the small vibration actuator 1 is indicated by designating the arrangement position, both the name of the small vibration actuator 1 and the coordinates of the arrangement position are shown as in the small vibration actuator 1 (0, 0).

  A method of applying a pulse wave to the information transmission apparatus according to the present embodiment will be described with reference to FIGS. FIG. 8 shows a tactile sensation felt by the living body when the small vibration actuators 1 mounted at two locations (points A and B) separated by about 60 mm from the living body are vibrated simultaneously and the peak values of the pulse waves at the two locations are changed. Indicates. The horizontal axis represents time, and the vertical axis represents the peak value of the pulse wave applied to the shape memory alloy body 6 of the small vibration actuator 1 mounted at each of two locations (points A and B). Further, the relationship between the magnitude of the stimulus given to the points A and B and the position of the stimulus felt by the living body is indicated by the symbols of the stimulus C and the antenna point D on the side of the graph. The size of the symbol of the stimulus C represents the size of the stimulus, and the position of the symbol of the tactile point D indicates where the living body felt the vibration source between the points A and B. In FIG. 8A, since the peak values of the pulse waves at the points A and B are the same 1 V, the living body feels that there is a vibration source at an intermediate point between the points A and B. In FIG. 8B, since the peak value at point A is 1V and the peak value at point B is 0.5V, the living body feels that there is a vibration source closer to point A. In FIG. 8C, since the peak value at point A is 0.5V and the peak value at point B is 1V, the living body feels that there is a vibration source closer to point B. In FIG. 8D, since the peak value at point A is 0.2V and the peak value at point B is 1V, the living body has a vibration source closer to point B than in FIG. 8C. To feel. In this way, it is possible to cause phantom sensation that makes a tactile sensation feel that a vibration source is present at a place where the vibration source does not actually exist.

  Next, a tactile sensation given to a living body when a pulse wave having the same height at points A and B is applied with a time difference will be described with reference to FIG. In FIG. 9, as in FIG. 8, the horizontal axis indicates time, and the vertical axis indicates the peak value of the pulse wave. Further, the tactile sensation of the moving speed of the vibration source is indicated by a symbol of movement sense E. The state of the moving speed of the vibration source felt by the living body is indicated by the swell of the arrow symbol of the movement sensation E, and the slower the swell, the slower the feeling is felt. 9A to 9D, the peak value of the pulse wave at the points A and B is 1 V, but the time difference from the application of the pulse voltage to the point A to the application of the pulse voltage to the point B is different. 9 (a), 100 ms, FIG. 9 (b), 200 ms, FIG. 9 (c), 350 ms, and FIG. 9 (d), 500 ms. 9A, the living body feels tactile as if the vibration source moved from point A to point B quickly. Then, as the time difference for applying the pulse wave to the points A and B becomes larger, the living body can cause an apparent movement that makes the tactile sensation feel as if the vibration source moved from the point A to the point B slowly.

  As described above, various information can be transmitted to the tactile sensation of the living body according to the application conditions to the two small vibration actuators 1. The operation of the information transmission apparatus according to this embodiment will be described with reference to FIG. When a signal in which the difference in peak value, time difference, application time, etc. are appropriately controlled is given to each of the small vibration actuators 1 in FIG. 7A, the vibration source moves relative to the entire surface on which the small vibration actuator 1 is disposed. It gives a tactile sensation and can transmit character information. For example, a pulse wave having a peak value of 1 V is applied to the small vibration actuator 1 (0, 2) to vibrate, and then a pulse wave having a peak value of 1 V is applied to the small vibration actuator 1 (1, 2) after 500 ms. Vibrate. Subsequently, similarly, a pulse wave is applied in order to the small vibration actuator 1 of (2, 2) (3, 2) (4, 2) (5, 2) (6, 2) to vibrate. The tactile sensation of the living body equipped with the information transmission device is (1, 2) (2, 2) (3, 2) (4, 2) (5, 2) (6, in order from the position (0, 2). The vibration source moves to the position of 2) and feels like being traced. By utilizing this fact, character information can be transmitted to the sense of touch of a living body.

  A specific method for transmitting character information will be described with reference to FIG. In FIG. 7B, the small vibration actuator 1 to which a pulse wave is applied is surrounded by a hatched frame. For example, when transmitting the letters “Large”, first, a pulse wave having a peak value of 1 V is changed from (0, 4) to (1, 4) (2, 4) (3,4) (4, 4) (5, 4). ) (6, 4) is sequentially applied at 500 ms intervals to vibrate. Next, after a few seconds, the vibration is applied in the same manner from (3, 6) to (3, 5) (3,4) (3, 3) (2, 2) (1, 1) (0, 0). Further, after a few seconds, vibration is applied in order from (3, 6) to (3, 5) (3,4) (3, 3) (4, 2) (5, 1) (6, 0). Thus, when a pulse wave is applied to the small vibration actuator 1, the living body changes from (0,4) to (6,4), from (3,6) to (0,0), and from (3,6) to (6 , 0), the vibration source moves and feels as if it was traced, so that the character “Large” can be recognized. Even if a pulse wave is simultaneously applied to the small vibration actuator 1 at the position of the “Large” character to vibrate, the living body can not recognize the character only by feeling vibration at a plurality of places. Character information can be transmitted to the living body by sequentially applying pulse waves to the small vibration actuator 1 with a time interval.

  Information transmission with vibration is possible by synchronizing the image with the information transmission apparatus according to the present embodiment. In addition, complex information such as scale information and conversation can be transmitted to the human sense of touch. Specific application examples are as follows. In the first application example, voice data and character data are presented as Braille and character information, and signal data transmitted from Braille blocks, stairs, gates, intersections, etc. It is an information transmission device that converts and presents information, and can transmit effective information to persons with disabilities. In this application example, the portion where the small vibration actuator 1 is disposed may be integrated with the information transmission device main body portion or may be separated. The second application example is an information transmission device according to the first application example, and includes a camera unit, and converts image data into information for tactile sensation. In the third application example, a UBS connection can be made with a personal computer, etc., characters and symbols are read from the screen of the personal computer and converted into character information, and the shape of an arbitrary object is converted into information for tactile sensation. The information from the personal computer can be known by touch. A fourth application example is an information transmission device that is applied to a wristwatch and includes a plurality of small vibration actuators 1 and transmits time as character information to a human body. You can know the time by touch. The fifth application example is an application to a steering wheel of an automobile, and the small vibration actuator 1 is disposed on the steering wheel portion. The information transmission device transmits a drowsy driving warning and information on the direction of travel of the vehicle from the car navigation to the tactile sense of the driver.

  In the information transmission apparatus according to the present invention, the small vibration actuators 1 may be arranged in a line, and if arranged in a line, the information transmission apparatus can be reduced in size and can transmit information only to a necessary part. Further, the small vibration actuator 1 may be arranged three-dimensionally, and if it is arranged three-dimensionally along the living body, more information can be transmitted to the living body.

  The information transmission apparatus can maximize its functions as information transmission means and communication means for persons with disabilities in the eyes and ears. Moreover, it can function effectively in an environment where transmission is restricted by sound information due to restrictions such as noise for others. In addition, since a simulated experience of tactile sensation by mechanical vibration is possible, it can be used for medical treatment, various trainings, games, and reproduction of phenomena in the bulkhead such as a magic hand.

  In addition, this invention is not restricted to the structure of the said various embodiment, A various deformation | transformation is possible in the range which does not change the meaning of invention. For example, the shape memory alloy main body 6 has a diameter of 50 μm, a length of 50 mm, and a linear shape of 2Ω, but may be adjusted so that vibration is generated when a pulse wave is applied regardless of the diameter, length, and resistance value. . The shape of the shape memory alloy main body 6 may be a thin plate. Further, when the temperature becomes higher than a predetermined temperature due to the shape memory effect, the shape memory alloy main body 6 may be bent to cause vibration. In addition, the living body that transmits information by vibration is not limited to a human being but may be an animal such as a dog. Further, the application conditions such as the peak value of the pulse wave, the application time, and the non-application time may be adjusted so that the shape memory alloy body 6 vibrates.

The block diagram of the information transmission apparatus which concerns on the 1st Embodiment of this invention. External view of the small vibration actuator. The characteristic view of the same shape memory alloy main body. The figure which shows the application conditions of the same pulse wave. The block diagram of the information transmission apparatus which concerns on the 2nd Embodiment of this invention. The block diagram of the information transmission apparatus which concerns on the 3rd Embodiment of this invention. (A) is a block diagram of the information transmission apparatus which concerns on the 4th Embodiment of this invention, (b) is explanatory drawing of the transmission method of the character in the information transmission apparatus. The figure which shows the application conditions of the simultaneous stimulation of the same pulse wave. The figure which shows the application conditions of the same peak value of the pulse wave. The block diagram of the information transmission apparatus of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Small vibration actuator 2 Pulse generator 6 Shape memory alloy main body 31 Vibration motor 32 Drive amplifier

Claims (2)

In an information transmission device to a living body using a shape memory alloy,
A shape memory alloy body;
The shape memory alloy main body comprises an on / off duty for signal transmission, and a pulse generator for applying a pulse voltage having the same or different peak value,
The shape memory alloy body is bent into a horseshoe shape and fixed at both ends, and the middle part of the alloy body is configured to be able to contact a living body,
To a living body characterized in that mechanical vibration is generated by repeatedly changing the length of the horseshoe-shaped portion of the alloy body by applying the pulse voltage, and information can be transmitted to the tactile sense of the living body. of the information transmission device. A plurality of the shape memory alloy main bodies are linearly or planarly or three-dimensionally arranged,
The pulse generator has a plurality of adjacent shape memory alloy bodies ,
When applying a pulse voltage at the same time, apply a pulse voltage with a different peak value before and after the passage of time,
When applying a pulse voltage of the same peak value, by applying a pulse voltage with a time difference to the other, the object moved between the adjacent alloy bodies to the living body in contact with the alloy body. The information transmission device to a living body according to claim 1, wherein the sense is given.

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