The invention discloses an obstacle detection method and system, which relate to the technical field of obstacle detection and are used to solve the problem of low accuracy of existing obstacle detection, the need to configure multiple ultrasonic transmitting device arrays to expand the detection range, and the need to configure a separate voice system for detection. Prompt question. The method includes: obtaining the phase information that needs to be adjusted for the digital speaker in the target object; each sound-emitting pixel unit generates sound waves of different phases according to the phase information, and superimposes the different sound waves on each other to form ultrasonic beams of different directivities; and receives the ultrasonic beam and transmits it to the target. The echo signal is reflected by obstacles within a preset distance range around the object; based on the echo signal, the type of obstacle and the distance between the obstacle and the target object are determined and a prompt sound is generated. The obstacle detection method provided by the present invention can expand the obstacle detection range without configuring multiple ultrasonic transmitting device arrays, and does not need to configure a separate voice system, thereby reducing costs.
1. An obstacle detection method, characterized by comprising:
Obtain the phase information that needs to be adjusted for the digital speaker in the target object; the digital speaker includes multiple sound-emitting pixel units;
Each of the sound-emitting pixel units generates acoustic wave pulse signals of different phases according to the phase information, and the different acoustic wave pulse signals are superimposed on each other to form ultrasonic beams of different directivities;
Receive an echo signal reflected by the ultrasonic beam transmitted to an obstacle within a preset distance range around the target object;
Determine the type of obstacle and the distance between the obstacle and the target object according to the echo signal;
A prompt tone is generated based on the type of obstacle and the distance.
2. The obstacle detection method according to claim 1, characterized in that the target object is a vehicle; the types of obstacles include static obstacles and dynamic obstacles; The distance beeps for obstacles include:
When the type of obstacle is a static obstacle, the first prompt sound is emitted according to the distance between the obstacle and the vehicle; when the type of obstacle is a dynamic obstacle, the first prompt sound is emitted according to the distance between the obstacle and the vehicle. The distance between the object and the vehicle emits a second prompt sound. The first prompt sound is used to remind the driver to avoid obstacles. The second prompt sound is used to remind the driver to avoid obstacles and warn of dynamic obstacles. Avoid vehicles.
3. The obstacle detection method according to claim 2, wherein generating a prompt sound according to the type of the obstacle and the distance includes:
Divide the distance between the obstacle and the target object into hazard levels; the smaller the distance, the higher the hazard level;
A prompt sound corresponding to the danger level is generated according to the danger level; the higher the danger level, the higher the urgency of the prompt sound.
4. The obstacle detection method according to claim 1, characterized in that the digital speakers include a plurality of digital speakers, the digital speakers correspond to sensors one-to-one, and the sensors are used to receive the echo signals, so Before obtaining the phase information that needs to be adjusted for the digital speaker in the target object, it also includes:
Obtaining an audio signal, the audio signal containing phase information that needs to be adjusted by the digital speaker in the target object;
Perform a preset waveform combination on the audio signal so that the digital speaker emits ultrasonic beams of different wavelengths, and the sensor detects the echo signal of the preset waveform combination and processes it;
The audio signal is encoded so that the sensor receives ultrasonic waves emitted by a corresponding digital speaker.
5. The obstacle detection method according to claim 1, characterized in that the target object is a sitting posture correction glasses, and the digital speaker and sensor are arranged in the sitting posture correction glasses. The distance between the obstacle and the beeping sound includes:
Determine whether the distance between the obstacle and the sitting posture correction glasses is less than the preset distance value. If the distance between the obstacle and the sitting posture correction glasses is less than the preset distance value, a message is issued to remind the user of the distance. Alert sound when an obstacle is too close.
6. The obstacle detection method according to claim 1, characterized in that, after receiving the echo signal reflected by the ultrasonic beam transmitted to the obstacle within a preset distance range around the target object, it further includes:
The echo signal is sent to an amplifier circuit for amplification, and the type of obstacle and the distance of the obstacle are determined based on the amplified echo signal.
7. The obstacle detection method according to claim 1, characterized in that the range of the directional ultrasonic beam emitted by the digital speaker is 30°, and the range of the directional ultrasonic beam emitted by the digital speaker is smaller than the obstacle detection range, in sequence. Forming directional ultrasound beams pointing in different directions includes:
After the digital speaker emits a directional ultrasonic beam pointing in the first direction, it emits a directional ultrasonic beam pointing in the second direction until the range of the emitted directional ultrasonic beam is equal to the obstacle detection range.
8. The obstacle detection method according to claim 4, wherein determining the type of obstacle and the distance between the obstacle and the target object according to the echo signal includes:
Extract the amplitude information and phase value of the echo signal; and obtain the time difference between the digital speaker transmitting the ultrasonic wave and the sensor receiving the echo signal;
Determine the distance and position of the obstacle based on the amplitude information, phase value and time difference;
The type of obstacle is determined based on the location of the obstacle corresponding to each echo signal.
9. An obstacle detection system, characterized in that it is applied to the obstacle detection method according to any one of claims 1 to 8, the system includes: a control unit and a digital speaker, the digital speaker includes a plurality of sound pixel unit;
The control unit obtains the phase information that needs to be adjusted for the digital speaker in the target object;
The control unit controls each of the sound-emitting pixel units to generate acoustic wave pulse signals of different phases according to the phase information, and superimposes the different acoustic wave pulse signals on each other to form ultrasonic beams of different directivities in turn;
The control unit receives the echo signal reflected by the ultrasonic beam transmitted to obstacles within a preset distance range around the target object;
The control unit determines the type of obstacle and the distance between the obstacle and the target object based on the echo signal;
The control unit generates a prompt sound according to the type of the obstacle and the distance.
10. The obstacle detection system according to claim 9, characterized in that the obstacle detection system further includes a sensor and an amplification circuit, the sensor is used to receive the ultrasonic beam emitted to a preset distance around the target object. The amplifying circuit is used to amplify the echo signal reflected by the obstacles within the range and send it to the control unit.
Technical field
The present invention relates to the technical field of obstacle detection, and in particular to an obstacle detection method and system.
Background technique
Due to the advantages of easy directional emission of ultrasonic waves, good directivity, easy control of intensity, slow energy consumption, long propagation distance in the medium, and no need for direct contact with the object being measured, ultrasonic waves are often used for distance
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