CN105943324A - An ultrasonic wave-based walking stick for the blind - Google Patents

Abstract

The invention provides an ultrasonic wave-based walking stick for the blind. The ultrasonic wave-based walking stick comprises an ultrasonic wave sensor, a photosensitive detection circuit, a single-chip microcomputer, an alarm circuit and a lighting circuit. The ultrasonic wave sensor emits an ultrasonic wave signal and receives an ultrasonic wave signal reflected back when the signal encounters a barrier; the single-chip microcomputer obtains the distance between the ultrasonic wave detection circuit and the barrier according to the duration from the time when the ultrasonic wave sensor emits the ultrasonic wave signal to the time when the ultrasonic wave sensor receives the ultrasonic wave signal reflected back when the signal encounters the barrier. When the distance between the ultrasonic wave sensor and the barrier is less than a safe distance, the alarm circuit generates vibration and gives voice prompt. The photosensitive detection circuit senses the intensity of external light, and when the illumination intensity is less than a set threshold value, the lighting circuit emits light.

Description

A crutch for the blind based on ultrasound

technical field

The invention relates to crutches for the blind, in particular to a crutch for the blind based on ultrasound.

Background technique

A cane is a simple walking aid, usually a wooden or metal stick with a handle on the top, which acts as a "third leg" for walking and keeps the body stable. Now there are also three-legged or four-legged ones, which enhance the anti-slip effect, and some are combined with a small folding stool. Crutches are generally used by the elderly and disabled.

With the development of science and technology, various types of crutches have appeared on the market, and there are also those specially designed for the blind. However, the functions of the crutches for the blind appearing on the market are relatively single, and they do not bring much convenience to the blind.

Contents of the invention

The technical problem to be solved by the present invention is to provide a crutch for the blind based on ultrasonic waves, which can detect obstacles on the road and give feedback to the blind, and at the same time, can prompt passers-by to walk in the opposite direction by emitting light when the light is weak.

In order to solve the problems of the technologies described above, the technical solution of the present invention is:

A crutch for the blind based on ultrasound, comprising an ultrasonic sensor, a photosensitive detection circuit, a single-chip microcomputer, an alarm circuit and a lighting circuit, the ultrasonic detection circuit sends an ultrasonic signal, and the ultrasonic detection circuit receives the ultrasonic signal reflected back by an obstacle, the The single-chip microcomputer obtains the distance between the ultrasonic detection circuit and the obstacle according to the time from when the ultrasonic detection circuit sends the ultrasonic signal to when the ultrasonic detection circuit receives the ultrasonic signal reflected by the obstacle. When the distance between obstacles is less than the safety distance, the alarm circuit generates vibration and voice prompts, the photosensitive detection circuit senses the intensity of external light, and when the light intensity is less than a set threshold, the lighting circuit emits light.

The trigger measurement pin of the ultrasonic sensor is electrically connected to the general-purpose output port of the single-chip microcomputer, and the feedback pin of the ultrasonic sensor is electrically connected to the general-purpose input port of the single-chip microcomputer.

The model of the single-chip microcomputer is STC15W204S.

The alarm circuit includes a first triode and a vibration motor, an output port of the microcontroller is electrically connected to the base of the first triode, and the collector of the first triode is connected to a positive 4.5V voltage , the emitter of the first triode drives the motor.

The alarm circuit includes a voice chip, a fifth capacitor, a sixth capacitor, a ninth capacitor, a horn and a second light-emitting diode, and the two output ports of the single-chip microcomputer are respectively electrically connected to the edge-triggered sound playback terminal of the voice chip and the The level of the voice chip triggers the playback terminal, the recording terminal of the voice chip is electrically connected to the fifth capacitor to the ground, the automatic gain control terminal of the voice chip is electrically connected to the ninth capacitor to the ground, and the voice chip is electrically connected to the ninth capacitor to the ground. The anode of the second light-emitting diode is connected to a positive 4.5V voltage, and the sixth capacitor is electrically connected between the ground terminal of the voice chip and the direct mode terminal of the voice chip, and the digital ground of the voice chip is connected to the voice chip. The analog grounds of the voice chips are electrically connected to the ground, the power supply terminal of the voice chip is connected to a positive 4.5V voltage, the oscillating resistance terminal of the voice chip is grounded, and the speaker output terminal of the voice chip drives the speaker.

The alarm circuit includes a seventh capacitor, an eighth capacitor, a tenth capacitor, a microphone and a recording button, the microphone input end of the voice chip is electrically connected to one end of the seventh capacitor, and the other end of the seventh capacitor is connected to the The microphone, one end of the tenth capacitor is electrically connected to the recording indicating end of the voice chip, the microphone reference end of the voice chip is electrically connected to one end of the eighth capacitor, and the other end of the eighth capacitor is respectively It is electrically connected with the microphone, the positive 4.5V voltage, and the other end of the tenth capacitor, and the recording end of the voice chip is grounded through the recording button.

The model of the voice chip is ISD1820.

The lighting circuit includes a first light-emitting diode and a first resistor, an output port of the single-chip microcomputer is electrically connected to the cathode of the first light-emitting diode, and an anode of the first light-emitting diode is electrically connected to the first resistor to a positive electrode. 4.5V voltage.

The photosensitive detection circuit includes a photoresistor. When the light intensity becomes weaker, the resistance value of the photoresistor becomes larger. The single-chip microcomputer outputs a low level, so that the first light-emitting diode emits light to remind passers-by walking in the opposite direction.

The cane for the blind also includes a power supply circuit, wherein the power supply circuit includes an electrical plug-in, a first switch, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor and a voltage stabilizing chip, and the output terminals of the electrical plug-in are respectively Electrically connect one end of the first capacitor and one end of the second capacitor, the output end of the electrical plug-in is electrically connected to the first switch to the input end of the voltage stabilizing chip, and the output end of the voltage stabilizing chip Respectively connect the positive 4.5V voltage, one end of the third capacitor and one end of the fourth capacitor, the ground terminal of the electrical plug-in, the other end of the second capacitor, and the other end of the first capacitor , the ground end of the voltage stabilizing chip, the other end of the third capacitor and the other end of the fourth capacitor are grounded.

The beneficial technical effect brought by the technical solution adopted in the present invention is:

Use ultrasonic technology to detect roadblocks, and feed back to the blind through vibration and voice broadcasts to improve the walking efficiency of the blind;

The photoresistor is used to sense the light intensity. When the light intensity is less than an adjustable threshold, the LED can emit light to remind passers-by who are walking in the opposite direction.

Description of drawings

Fig. 1 is a system block diagram of an embodiment of the present invention;

Fig. 2 is a circuit diagram of an embodiment of the present invention;

Fig. 3 is a working flow diagram of an embodiment of the present invention.

detailed description

In order to make the object, technical solution and advantages of the present invention clearer, various embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

Comprehensively referring to Figure 1 and Figure 2, the STC15W204S MCU is electrically connected to the ultrasonic sensor, photosensitive detection circuit, alarm circuit and lighting circuit respectively. The distance between the ultrasonic wave and the obstacle is obtained from the time when the ultrasonic sensor sends the ultrasonic signal to the time when it receives the ultrasonic signal sent back by the obstacle. When the distance between the ultrasonic detection circuit and the obstacle is less than the safe distance, the alarm circuit vibrates and voice prompts. The photosensitive detection circuit senses the intensity of external light, and when the light intensity is less than a set threshold, the lighting circuit emits light.

The trigger measurement pin Trig of the ultrasonic sensor is electrically connected to the general output port p1.2 of the STC15W204S microcontroller, and the feedback pin Echo of the ultrasonic sensor is electrically connected to the general input port p1.3 of the STC15W204S microcontroller.

The alarm circuit includes a first triode Q1 and a vibration motor B1, an output port p1.0 of the STC15W204S microcontroller is electrically connected to the base of the first triode Q1, and the collector of the first triode Q1 is connected to a positive 4.5V voltage , the emitter of the first triode Q1 drives the motor B1, when the base of the first triode Q1 is at a high level, the vibration motor B1 does not vibrate; when the base of the first triode Q1 is at a low level, it emits The pole and the collector are turned on, and the vibration motor B1 vibrates.

The alarm circuit includes the ISD1820 voice chip, the fifth capacitor C5, the sixth capacitor C6, the ninth capacitor C9, the speaker LS1 and the second light-emitting diode D2, and the two output ports p3.6 and p3.7 of the STC15W204S microcontroller are respectively electrically connected to the ISD1820 voice The edge of the chip triggers the playback terminal PLAYE and the level of the ISD1820 voice chip triggers the playback terminal PLAYL. The recording terminal REC of the ISD1820 voice chip is electrically connected to the fifth capacitor C5 to ground, and the automatic gain control terminal AGC of the ISD1820 voice chip is electrically connected to the first capacitor. Nine capacitors C9 to ground, the anode of the second light-emitting diode D2 is connected to a positive 4.5V voltage, the digital ground VSSD of the ISD1820 voice chip and the through mode terminal FT of the ISD1820 voice chip are electrically connected to the sixth capacitor C6, and the digital ground of the ISD1820 voice chip The ground VSSD and the analog ground VSSA of the ISD1820 voice chip are electrically connected to the ground, the power supply terminal VCC of the ISD1820 voice chip is connected to a positive 4.5V voltage, the oscillating resistor terminal ROSC of the ISD1820 voice chip is grounded, and the speaker LS1 output terminals SP+ and SP- of the voice chip are driven Horn LS1.

The alarm circuit includes the seventh capacitor C7, the eighth capacitor C8, the tenth capacitor C10, the microphone MK1 and the recording button S2, the microphone input terminal MIC of the ISD1820 voice chip is electrically connected to one end of the seventh capacitor C7, and the other ends of the seventh capacitor C7 are respectively It is electrically connected with the microphone MK1, one end of the tenth capacitor C10, and the recording indicator end RECLED of the ISD1820 voice chip, and the microphone reference end MICREF of the ISD1820 voice chip is electrically connected with one end of the eighth capacitor C8, and the other end of the eighth capacitor C8 is respectively connected to the microphone MK1 , the positive 4.5V voltage, and the other end of the tenth capacitor C10 are electrically connected, and the recording terminal REC of the ISD1820 voice chip is grounded through the recording button S2. After the ISD1820 voice chip is powered on, the recording prompt content can be modified through the recording button S2. The steps are to press and hold the recording button S2, speak to the microphone MK1, release the recording button S2, and the recording is completed, and the next voice prompts the content of the previous recording.

The lighting circuit includes a first light-emitting diode D1 and a first resistor R1, an output port p1.1 of the STC15W204S microcontroller is electrically connected to the cathode of the first light-emitting diode D1, and the anode of the first light-emitting diode D1 is electrically connected to the first resistor R1 to positive 4.5 V voltage.

The photosensitive detection circuit includes a photosensitive resistor. When the light intensity becomes weaker, the resistance value of the photosensitive resistor becomes larger. When the resistance value of the photosensitive resistor is greater than the set threshold, after passing through the comparator of the STC15W204S single-chip microcomputer, the STC15W204S single-chip microcomputer outputs a low level, so that The first light-emitting diode D1 emits light to remind passers-by walking in the opposite direction.

The cane for the blind also includes a power supply circuit, wherein the power supply circuit includes an electrical plug-in P1, a first switch S1, a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4 and a voltage regulator chip REG1117-5, so The No. 2 pin of the output end of the electrical plug-in P1 is electrically connected to one end of the first capacitor C1 and one end of the second capacitor C2 respectively, and the No. 2 pin of the output end of the electrical plug-in P1 is electrically connected to the first capacitor C1. Switch S1 to the input terminal IN of the voltage stabilizing chip REG1117-5, the output terminal OUT of the voltage stabilizing chip REG1117-5 is respectively connected to the positive 4.5V voltage, one end of the third capacitor C3 and the fourth capacitor One end of C4, pin No. 1 of the ground terminal of the electrical plug-in P1, the other end of the second capacitor C2, the other end of the first capacitor C1, and the ground terminal of the voltage stabilizing chip REG1117-5 GND, the other end of the third capacitor C3 and the other end of the fourth capacitor C4 are grounded.

As shown in Figure 3, firstly initialize the STC15W204S microcontroller. When night comes, the light intensity is less than the set threshold (defined by the photoresistor), the first light emitting diode D1 in the lighting circuit emits light; when it is daytime, the light intensity is greater than the set threshold, the first light emitting diode D1 of the lighting circuit Does not shine. The ultrasonic sensor emits ultrasonic signals to continuously detect obstacles. When an obstacle is encountered within the detection range, the alarm circuit will generate vibration and voice prompts to remind blind users to change the walking direction and pay attention to safety.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (8)

1. a blind-man crutch based on ultrasound wave, it is characterised in that: include ultrasonic sensor, photosensitive inspection Slowdown monitoring circuit, single-chip microcomputer, circuit for alarming and lighting circuit, described ultrasound detection circuit sends ultrasonic signal, Described ultrasound detection circuit receives meets the ultrasonic signal that reflects of barrier, described single-chip microcomputer according to from Described ultrasound detection circuit sends ultrasonic signal and receives chance barrier to described ultrasound detection circuit The time of the ultrasonic signal reflected obtains the distance between described ultrasound detection circuit and barrier, When distance between described ultrasound detection circuit and barrier is less than safe distance, described circuit for alarming produces Voice message is vibrated and is sent in life, and described photosensitive detection circuit sensing external light intensity, when intensity of illumination is little In time setting threshold value, described lighting circuit is luminous.

2. blind-man crutch as claimed in claim 1, it is characterised in that: the triggering of described ultrasonic sensor Measure pin to electrically connect with the general purpose outputs mouth of described single-chip microcomputer, the feedback pin of described ultrasonic sensor Electrically connect with the universal input port of described single-chip microcomputer.

3. blind-man crutch as claimed in claim 1, it is characterised in that: the model of described single-chip microcomputer is STC15W204S。

4. blind-man crutch as claimed in claim 1, it is characterised in that: described circuit for alarming includes the one or three Pole pipe and vibrating motor, an output port of described single-chip microcomputer electrically connects with the base stage of described first audion, The colelctor electrode of described first audion connects positive 4.5V voltage, and the emitter stage of described first audion drives described Motor.

5. blind-man crutch as claimed in claim 1, it is characterised in that: described circuit for alarming includes voice core Sheet, the 5th electric capacity, the 6th electric capacity, the 9th electric capacity, loudspeaker and the second light emitting diode, described single-chip microcomputer Two output ports are electrically connected the edging trigger playback end of described speech chip and described speech chip Level triggers playback end, described speech chip recording end electrically connect described 5th electric capacity to ground, institute's predicate The automatic growth control end of sound chip electrically connects described 9th electric capacity to ground, the sun of described second light emitting diode Pole connects positive 4.5V voltage, the ground terminal of described speech chip and described speech chip direct mode operation end it Between electrically connect the 6th electric capacity, being digitally jointly electrically connected with the simulation of described speech chip ground of described speech chip Ground connection, the power supply of described speech chip terminates positive 4.5V voltage, the concussion resistance termination of described speech chip Ground, the loudspeaker outfan of described speech chip drives described loudspeaker.

6. blind-man crutch as claimed in claim 5, it is characterised in that: described circuit for alarming includes the 7th electricity Appearance, the 8th electric capacity, the tenth electric capacity, microphone and record button, the microphone input of described speech chip is electrically connected Connect one end of described 7th electric capacity, the other end of described 7th electric capacity respectively with described microphone, described tenth electricity The one end held and the recording indication end electrical connection of described speech chip, the microphone reference edge electricity of described speech chip Connect one end of described 8th electric capacity, the other end of described 8th electric capacity respectively with described microphone, positive 4.5V Voltage, the other end electrical connection of described tenth electric capacity, the recording end of described speech chip is pressed by described recording Button ground connection.

7. blind-man crutch as claimed in claim 1, it is characterised in that: the model of described speech chip is ISD1820。

8. blind-man crutch as claimed in claim 1, it is characterised in that: described lighting circuit includes first The negative electrode of optical diode and the first resistance, an output port of described single-chip microcomputer and described first light emitting diode Electrical connection, the anode of described first light emitting diode electrically connects described first resistance to positive 4.5V voltage.