JPH0415218Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a guide device for assisting a blind person in walking.

Blind people use white canes to avoid obstacles and danger when walking, and they rely on the perception of environmental sounds and wind to understand their surroundings. However, this information alone was insufficient, and a device using ultrasound was devised. Some of these devices are used as ranging devices that change the frequency of sound according to the distance to the obstacle, and others utilize auditory sound source localization, which uses multiple ultrasonic receiving elements to determine the distance and direction of the obstacle. There are devices that localize a corresponding sound image. Since the means of transmitting information to the blind person in these devices is auditory, the environmental sounds mentioned above are masked, and as a result, the amount of information from the environmental sound decreases, and the overall amount of information perceived by the blind person does not increase. Devices using this type have the disadvantage of high current consumption, making them unsuitable as walking aid devices. Furthermore, when blind people take the device away from their hands, they are unable to check whether the power switch is open or closed, which a sighted person can easily do, and they tend to forget to turn off the power switch.

The present invention was developed in view of the above points, and the method of transmitting information obtained from a distance measuring device to a blind person is to use tactile sensation through stimulation of low frequency vibration, and by integrating the vibrator for this purpose with a power switch. When a blind person needs information, he or she presses a push button switch and the power is turned on, at the same time vibrations from the pressing part are transmitted to the fingertips. Therefore, a blind person can perceive the distance to an obstacle, thereby saving power and preventing forgetting to turn off the power.

The distance measuring device used in the device of this invention uses infrared light and can detect objects up to about 10 meters away.

Distance can be measured because infrared light emitted from a light emitting element is projected onto an object in the form of a beam, and the intensity of the infrared light reflected and incident on a light receiving element is inversely proportional to the second power of distance. The intensity of the received light at this time affects the reflectance of the reflective object, but infrared light of about 1 micron has less difference between various objects than visible light, so it is not a practical problem as a walking aid device for the blind. For example, there is only a 10% difference in reflectance between blue and red reflective objects. Additionally, since the emitted light beam can be focused narrowly, it is possible to determine the direction at the same time as distance measurement. It can be used as a short-range radar.

When using ultrasonic waves, it is practically difficult to reduce the aperture of the projection beam to less than 20 degrees, but in the case of the present invention, it can be reduced to about 1/10 of that.

Examples will be described below with reference to the drawings.

Fig. 1 is a block electrical circuit diagram of the device of the present invention, Fig. 2 is a time chart showing the circuit operation, Fig. 3,
FIG. 4 shows the external appearance and sectional view of the device, respectively. Identical symbols represent identical members. Next, the device of the present invention will be explained using FIGS. 1 and 2.

By closing the power switch 2, the battery 1 is connected to the terminal 3 with symbols 4, 5, 12, 15, 1, which will be described later.
A current is supplied to each circuit shown by 6. The output waveform of the oscillation circuit 4 in the part indicated by symbol A is shown in FIG. 2 by symbol A, and the repetition frequency is 100
In hertz, the pulse width is about 10 microseconds. This pulse wave is input to the drive circuit 5 and supplies current to the light emitting diode 6. If the peak current value at this time is 1 ampere, the average current consumption will be about 1 milliampere. Infrared light emitted from the light emitting diode 6 is converted into parallel light by a lens 7 and projected onto an object, and the reflected light is focused by a lens 10 and enters a photodiode 11. Symbols 8 and 9 indicate the directions of the projected light and reflected light, respectively. The photodiode 11 generates a current proportional to the intensity of the incident light, which is converted into a voltage signal that is amplified by the amplifier circuit 12. At this time, disturbance light from the sun and illumination lights also enters the photodiode 11, so the output of the amplifier circuit 12 (the part indicated by symbol B)
The signal waveform of is shown in FIG. 2B.

Since the capacitor 13 and the resistor 14 constitute a high-pass filter, the influence of ambient light is removed. The signal waveform of the part indicated by symbol C is
Shown in Figure C. As described above, the peak value of this pulse is inversely proportional to the second power of the distance to the object. The signal from the bypass filter (portion indicated by symbol C) is input to the sample-and-hold circuit 15 and sampled in synchronization with the output signal of the oscillation circuit 4 (portion indicated by symbol A). The output signal of the sample and hold circuit 15 (the part indicated by symbol D) is
Shown in Figure D. This signal is input to the V/F conversion circuit 16 and oscillates at a frequency (1 kilohertz or less) proportional to the input voltage. The output signal of the V/F conversion circuit 16 (the part indicated by symbol E) is applied to the vibrator 17. Therefore, it vibrates at a frequency that is inversely proportional to the second power of the distance to the object. Next, the pushbutton 18, which integrates the power switch 2 and the vibrator 17, will be explained according to the embodiment shown in FIGS. 5 and 6.

Symbols 22 and 23 in FIG. 5 represent the housing of the push button switch, respectively, and the electrical switch housed inside the housing 22 is closed only when the cap 23 is pressed by the cap of the push button that serves as the pressing part. There is. Symbol 30 is a lead-out line of such an electric switch.

The diaphragm 24 has a push button switch housing 2 on its top surface.
A voice coil 25 is fixed to the lower surface of the voice coil 2, and the periphery of the voice coil 25 is supported by a housing 27 via an edge 26 so as to move up and down. A magnet 28 is fixed to the housing 27 inside the voice coil 25. Therefore, by passing a low frequency current, that is, the output at point E in FIG.
4, transmitted to the housing 22 and cap 23.

FIG. 6 shows a different embodiment from FIG. 5, and the same symbols represent the same members. A piezoelectric element 32 that vibrates in the thickness direction is fixed to the upper surface of the pressing portion 31, and a cap 23 serving as a push button is further fixed to the upper surface of the piezoelectric element 32. Therefore, by applying a low frequency voltage to the piezoelectric element 32, it vibrates vertically at the same frequency, and this vibration is transmitted to the cap 23. An electric switch (not shown) is housed inside the housing 22, and as in the embodiment shown in FIG.
By pressing 3 with your finger from above to below, the electric switch (shown as symbol 2 in Figure 1) is activated.
is injected. At this time, the vibration of the frequency and width corresponding to the distance information to the object is transmitted to the finger, so the blind person can obtain information about the direction and distance of the object, and it becomes an auxiliary means for walking. . Fifth
The symbol 29 in the figure is a lead wire of the voice coil 25, and the symbol 29 in FIG. Further, the symbol 30 is also a lead-out line of an electric switch.

Figure 3 is an external view of the device of the present invention, and Figure 4 is
It shows the cross section. Next, both will be explained together.

Symbol 19 is a casing (outer casing), which is made by plastic molding. Lenses 7 and 10 are fixed to the front, and a light emitting diode 6 and a photodiode 11 are fixed to the rear thereof, and are located at approximately the focal point of each lens.

Symbol 21 is an electric circuit board with a first
Circuits indicated by symbols 4, 5, 12, 15, and 16 in the figure are installed, but are omitted and not shown. Symbol 1 is a dry battery, which supplies power to the board 21 via a terminal 20 (which serves as a battery holder).

Symbol 18 indicates the push button (cap) of the push button switch explained with reference to FIGS. Then, as mentioned above, the finger will sense vibrations, allowing the user to know the distance and direction to the object. Therefore, when a blind person wants to know the distance of an obstacle that is far away while walking, he can hold the device of the present invention in his hand and press the vibrator with his fingertip, and the distance to the obstacle in the direction he is facing can be determined. It is transmitted to the blind person as frequency vibrations. This has the effect of providing a practical walking aid device for blind people in which the power is turned off at the same time by simply removing the finger from the vibrator when the information is not needed.

[Brief explanation of the drawing]

Fig. 1 is a block electrical circuit diagram of the device of the present invention, Fig. 2 is a time chart showing electrical signals of each part of Fig. 1, and Figs. 3 and 4 are an external view and a cross section showing the inside of the device of the present invention, respectively. It is a diagram. FIGS. 5 and 6 are explanatory diagrams, respectively, of a member that integrally constitutes a power switch and a vibrator used in the device of the present invention. 1... Battery, 2... Power switch, 3... Terminal, 4... Oscillation circuit, 5... Drive circuit, 6... Light emitting diode, 7, 10... Lens, 11... Photo diode, 12... Amplifier circuit, 13... Capacitor, 14... Resistor, 15... Sample hold circuit, 16... V/F conversion circuit, 17... Vibrator, 18... Push button, 19, 22, 27...
Housing, 20... Battery holder, 21... Electric circuit board, 23... Cap, 24... Vibration plate, 25...
... Voice coil, 26 ... Edge, 28 ... Magnet, 29, 30 ... Lead wire, 31 ... Pressing part, 32 ... Piezoelectric element.

Claims (1)

[Scope of utility model registration request] An infrared light emitting device converges infrared light into a narrow beam by a converging optical system and emits it forward, and a converging optical system converges the reflected light from the irradiated object by the emitted beam of the infrared light emitting device. The infrared light emitted from the photoelectric element that receives light and the infrared light emitting device is modulated at a predetermined frequency and output as intermittent infrared light. The output of the photoelectric element is synchronously detected, and the output of the photoelectric element is detected proportional to the received light intensity. an electric circuit that obtains an electric signal that provides distance information to an object; an oscillation circuit that generates electric vibrations that have a frequency and amplitude that correspond to the magnitude of the electric signal that provides distance information obtained from the electric circuit;
A manual electric switch that opens and closes the power supply circuit of the electric circuit and oscillation circuit described above, and a device that transmits the vibrations of a vibrator operated by the electric vibrations of the oscillation circuit to a human hand to sense the distance to an object. A guide device for a blind person characterized by comprising: