Distance testing and tested object contour recognition method based on ultrasonic sensor module

Abstract

The invention relates to the technical field of sensors, in particular to a distance test and tested object contour recognition method based on an ultrasonic sensor module, which comprises the following steps: applying a driving signal to an ultrasonic sensor to emit ultrasonic waves; echo signals are collected in real time, and filtering signals are generated; carrying out real-time statistics on a primary echo peak value and transit time from the filtered signal; calculating the distance between the ultrasonic sensor and the measured object in real time based on the transit time, and judging whether the measured object is convex or concave according to the distance between the ultrasonic sensor and the measured object; and the convex or concave degree of the measured object is judged by combining the change trend of the continuous primary echo peak value. According to the invention, obstacle distance measurement and contour recognition can be realized without adding an additional sensor.

Description

Technical Field

[0001] The present application relates to the field of sensor technology, and in particular to a distance testing and object contour recognition method based on an ultrasonic sensor module. Background Art

[0002] With the rapid development of smart devices, sweeping robots are an important tool for household cleaning. Their environmental perception ability is crucial to cleaning efficiency and obstacle avoidance. In practical applications, sweeping robots need to quickly and accurately detect obstacles in the surrounding environment to avoid collisions or jams. Ultrasonic sensors are widely used in sweeping robots due to their low cost and strong anti-interference ability to detect the distance and material of obstacles. However, the functions of ultrasonic sensors in the prior art are usually limited to distance measurement or simple material detection, and cannot provide detailed shape and contour information of obstacles.

[0003] At present, in order to improve the ability of sweeping robots to perceive obstacles, the existing technology mainly adopts the method of adding optical sensors or using ultrasonic sensors that transmit and receive multiple objects or transmit and receive multiple objects. Although the above methods can improve the perception ability to a certain extent, they all have problems such as high cost, complex equipment or insufficient adaptability. In view of the above shortcomings, there is an urgent need for a method that can measure the distance of obstacles and recognize the contours of the shapes without adding additional sensors, so as to reduce costs while improving the accuracy and reliability of environmental perception. Summary of the invention

[0004] This application provides a distance test and object contour recognition method based on an ultrasonic sensor module, which can achieve obstacle distance measurement and shape contour recognition without adding additional sensors. This application provides the following technical solutions:

[0005] In a first aspect, the present application provides a distance test and object contour recognition method based on an ultrasonic sensor module, the method comprising:

[0006] Applying a driving signal to the ultrasonic sensor to emit ultrasonic waves;

[0007] Collect echo signals in real time and generate filtered signals;

[0008] Counting the peak value and transit time of an echo from the filtered signal in real time;

[0009] Calculating the distance between the ultrasonic sensor and the object to be measured in real time based on the transit time, and judging whether the object to be measured is convex or concave according to the distance between the ultrasonic sensor and the object to be measured;

[0010] The degree of protrusion or depression of the object to be measured is determined by combining the changing trend of the continuous peak values ​​of the primary echoes.

[0011] In a specific embodiment, applying a driving signal to the ultrasonic sensor to emit ultrasonic waves comprises:

[0012] A driving signal is applied to both ends of the ultrasonic sensor probe to stimulate the sensor to emit ultrasonic waves. The driving signal is in the form of a bidirectional square wave, the driving frequency is 300kHz, the number of single waves is 5, the driving voltage is 10V, and the interval time of the driving waveform is 10ms.

[0013] In a specific implementation scheme, the real-time acquisition of echo signals and generation of filtered signals includes:

[0014] Performing bandpass filtering on the collected echo signal;

[0015] Use dynamic noise floor detection method to identify the baseline of environmental noise, and restore the echo signal in combination with the filtering result;

[0016] Output the processed filtered signal.

[0017] In a specific implementation scheme, the real-time statistics of an echo peak value and a transit time from the filtered signal include:

[0018] The ultrasonic sensor starts counting when it emits ultrasonic waves. After the ultrasonic waves are reflected by the object being measured, the ultrasonic receiving circuit detects the echo signal and amplifies and filters it. When the ultrasonic echo is identified, the counting stops at the same time. The value obtained by the counter at this time is the transit time.

[0019] In a specific possible implementation scheme, the real-time calculation of the distance between the ultrasonic sensor and the object to be measured based on the transit time, and the determination of whether the object to be measured is convex or concave according to the distance between the ultrasonic sensor and the object to be measured include:

[0020] Based on the known ultrasonic propagation speed c, the distance D between the ultrasonic sensor and the object to be measured is calculated: D = c*t / 2.

[0021] In a specific possible implementation manner, the real-time calculation of the distance between the ultrasonic sensor and the object to be measured based on the transit time, and judging whether the object to be measured is a protrusion or a depression according to the distance between the ultrasonic sensor and the object to be measured further comprises:

[0022] Determine the shape of the surface of the object being measured based on the distance change calculated in real time;

[0023] If the detected distance increases, it means that the object being measured is concave;

[0024] If the detected distance decreases, it means that the object being measured is a convexity;

[0025] If the detected distance remains unchanged, it means that the object being measured is a plane.

[0026] In a specific implementation scheme, judging the degree of protrusion or depression of the object under test by combining the continuous change trend of the peak value of the primary echo includes:

[0027] If there is a change difference between the peak values ​​of consecutive echoes, it means that the object being measured is a vertical protrusion / depression;

[0028] If there is almost no change difference in the peak values ​​of consecutive echoes, it means that the object being measured is convex / concave at 45 degrees;

[0029] Combined with the protrusions and depressions previously determined based on the distance, the outline of the object being measured is identified.

[0030] In the second aspect, the present application provides a distance test and object contour recognition system based on an ultrasonic sensor module, which adopts the following technical solutions:

[0031] A distance test and object contour recognition system based on an ultrasonic sensor module, comprising:

[0032] An ultrasonic transmitting module, used for applying a driving signal to the ultrasonic sensor to transmit ultrasonic waves;

[0033] A filter signal generation module, used for real-time acquisition of echo signals and generation of filter signals;

[0034] A data statistics module, used for real-time statistics of an echo peak value and a transit time from the filtered signal;

[0035] A distance judgment module, used for calculating the distance between the ultrasonic sensor and the object to be measured in real time based on the transit time, and judging whether the object to be measured is convex or concave according to the distance between the ultrasonic sensor and the object to be measured;

[0036] The primary echo peak value judgment module is used to judge the degree of protrusion or depression of the object under test based on the change trend of the continuous primary echo peak values.

[0037] In a third aspect, the present application provides an electronic device comprising a processor and a memory; the memory stores a program, and the program is loaded and executed by the processor to implement a distance test and object contour recognition method based on an ultrasonic sensor module as described in the first aspect.

[0038] In a fourth aspect, the present application provides a computer-readable storage medium, in which a program is stored. When the program is executed by a processor, it is used to implement a distance test and a contour recognition method of an object to be measured based on an ultrasonic sensor module as described in the first aspect.

[0039] In summary, the beneficial effects of this application include at least:

[0040] 1) This application uses an existing single ultrasonic sensor module to achieve distance measurement and contour recognition, without the need for additional optical sensors or multi-transmitter ultrasonic sensors. This effectively reduces the cost of hardware equipment and reduces the space occupied by the system, making the device more compact and convenient for integrated application in sweeping robots.

[0041] 2) While measuring distance in real time, the shape of the object being measured, including protrusions, depressions and their degree, is accurately identified through the characteristic changes of the echo signal. Through dynamic background noise detection and filtering processing, environmental noise interference is eliminated to ensure the accuracy of the measurement signal, thereby improving the adaptability to complex environments and perception reliability.

[0042] 3) It can not only detect the existence of obstacles, but also identify the outline of obstacles (for example, concave slopes or convex slopes), so that the sweeping robot can avoid risks more efficiently when facing complex obstacles and avoid getting stuck or damaged due to being involved in obstacles. It improves the robot's path planning and dynamic obstacle avoidance capabilities, greatly optimizing cleaning efficiency and operational safety.

[0043] Apply a driving signal to the ultrasonic sensor to emit ultrasonic waves, collect echo signals in real time and generate filter signals, count the peak value and transit time of a single echo from the filter signal, calculate the distance between the ultrasonic sensor and the object to be measured based on the transit time and judge its convex or concave state, and finally judge the degree of convexity or concave of the object to be measured by combining the continuous change trend of the peak value of the single echo. Through this method, the distance measurement and basic recognition of the shape contour of the obstacle can be achieved without adding additional sensors, which reduces the system cost and structural complexity, and at the same time improves the accuracy and reliability of the sweeping robot's perception of the environment.

[0044] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present application in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a flow chart of a distance test and a contour recognition method of an object to be measured based on an ultrasonic sensor module in an embodiment of the present application.

[0046] Figure 2 It is a schematic diagram of a use case of a driving signal in an embodiment of the present application.

[0047] Figure 3 It is a waveform comparison diagram before and after echo signal processing in the embodiment of the present application.

[0048] Figure 4 This is a use case diagram of the design scenario in the verification experiment in the embodiment of this application. Figure 1 .

[0049] Figure 5 This is a use case diagram of the design scenario in the verification experiment in the embodiment of this application. Figure 2 .

[0050] Figure 6 It is a changing trend diagram of the distance of scene A and the peak value of an echo in the embodiment of the present application.

[0051] Figure 7 It is a changing trend diagram of the distance of scene B and the peak value of an echo in the embodiment of the present application.

[0052] Figure 8 It is a changing trend diagram of the distance of scene C and the peak value of an echo in the embodiment of the present application.

[0053] Fig. 9 It is a trend diagram of the distance of scene D and the peak value of an echo in the embodiment of the present application.

[0054] Fig.10 It is a block diagram of an electronic device for distance testing and contour recognition of an object under test based on an ultrasonic sensor module in an embodiment of the present application. DETAILED DESCRIPTION

[0055] The specific implementation methods of the present application are further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but are not intended to limit the scope of the present application.

[0056] Optionally, the present application uses the distance testing and object contour recognition methods based on the ultrasonic sensor module provided in each embodiment as an example used in an electronic device, where the electronic device is a terminal or a server. The terminal can be a mobile phone, a computer, a tablet computer, etc. This embodiment does not limit the type of electronic device.

[0057] Reference Figure 1 , is a flow chart of a method for distance testing and object contour recognition based on an ultrasonic sensor module provided by an embodiment of the present application, the method comprising at least the following steps:

[0058] Step S101: applying a driving signal to the ultrasonic sensor to emit ultrasonic waves.

[0059] In step S101, a driving signal is applied to both ends of the ultrasonic sensor probe to stimulate the sensor to emit ultrasonic waves. Specifically, the driving signal is as follows: Figure 2 As shown, the signal form is a bidirectional square wave, the driving frequency is 300kHz, the number of single waves is 5, the driving voltage is 10V, and the interval time of the driving waveform is 10ms.

[0060] Step S102: collect echo signals in real time and generate filtered signals.

[0061] In step S102, the echo signal received by the ultrasonic sensor is then processed by the ADC module of the MCU. Specifically, the collected echo signal is bandpass filtered to extract the effective signal within the target frequency band, while filtering out noise interference that is not related to the ultrasonic frequency. The baseline of the environmental noise is identified using a dynamic background noise detection method, and the echo signal is further restored in combination with the filtering result to ensure that only effective information related to the surface characteristics of the object being measured is retained in the signal, and the processed filtered signal is output. The waveform comparison diagram before and after echo signal processing is shown in the figure below. Figure 3 shown.

[0062] Step S103: Count the peak value and transit time of an echo in real time from the filtered signal.

[0063] In step S103, based on the filter signal generated in step S102, the peak value of the primary echo is detected and counted in real time. At the same time, the time axis of the filter signal is analyzed to calculate the time of arrival of the echo, thereby obtaining the transit time.

[0064] Specifically, the ultrasonic sensor starts counting when it emits ultrasonic waves. After the ultrasonic waves are reflected by the object being measured, the ultrasonic receiving circuit detects the echo signal for amplification and filtering. When the ultrasonic echo is identified, the counting stops at the same time. The value obtained by the counter at this time is the transit time.

[0065] Step S104: Calculate the distance between the ultrasonic sensor and the object to be measured in real time based on the transit time, and determine whether the object to be measured is convex or concave according to the distance between the ultrasonic sensor and the object to be measured.

[0066] In step S104, the distance D between the ultrasonic sensor and the object to be measured is calculated using the transit time t obtained in step S103 and based on the known ultrasonic wave propagation speed c: D = c*t / 2.

[0067] In implementation, the shape of the surface of the object being measured is determined based on the distance change calculated in real time. If the detected distance increases, it means that the object being measured is concave. If the detected distance decreases, it means that the object being measured is convex. If the detected distance remains unchanged, it means that the object being measured is flat.

[0068] Step S105: Determine the degree of protrusion or depression of the object under test based on the change trend of the peak values ​​of consecutive primary echoes.

[0069] In step S105, based on the peak value of the primary echo extracted in step S103, the degree of protrusion or depression of the object to be measured is determined. In this application, the specific contour of the object to be measured cannot be identified, and only vertical protrusions / depressions or 45-degree protrusions / depressions are identified.

[0070] Specifically, if the difference between the peak values ​​of consecutive echoes is small, it means that the object under test is a vertical convexity / concavity. If the difference between the peak values ​​of consecutive echoes is large, it means that the object under test is a 45-degree convexity / concavity. At the same time, combined with the convexity and concavity previously determined based on the distance, the outline of the object under test is finally identified.

[0071] In summary, by applying a driving signal to the ultrasonic sensor to emit ultrasonic waves, the echo signal is collected in real time and a filter signal is generated. The peak value and transit time of a single echo are counted from the filter signal. The distance between the ultrasonic sensor and the object to be measured is calculated based on the transit time and its convex or concave state is judged. Finally, the degree of convexity or concave of the object to be measured is judged in combination with the continuous trend of the peak value change of the single echo. Through this method, the distance measurement and basic recognition of the shape contour of the obstacle can be achieved without adding additional sensors, which reduces the system cost and structural complexity, and at the same time improves the accuracy and reliability of the sweeping robot's perception of the environment.

[0072] In order to verify the technical effect of this application, this application is verified by experiments. Specifically, refer to Figure 4 and Figure 5 Four experimental scenarios were designed in the verification step of this application, namely, scenario A, scenario B, scenario C, and scenario D, wherein scenario A is used to simulate vertical convexity, scenario B is used to simulate vertical concavity, scenario C is used to simulate 45-degree convexity, and scenario D is used to simulate 45-degree concavity. Figure 6 , Figure 7 , Figure 8 , Fig. 9 The distances of scene A, scene B, scene C, and scene D and the changing trend diagrams of the peak value of an echo are respectively shown. According to the accompanying drawings, it can be seen that the judgment process in the present application is well-founded and not an unfounded guess.

[0073] An embodiment of the present application further provides a distance test and object contour recognition system based on an ultrasonic sensor module, the system comprising at least the following modules:

[0074] An ultrasonic transmitting module, used for applying a driving signal to the ultrasonic sensor to transmit ultrasonic waves;

[0075] A filter signal generation module, used for real-time acquisition of echo signals and generation of filter signals;

[0076] A data statistics module is used to count the peak value and transit time of an echo from the filtered signal in real time;

[0077] A distance judgment module is used to calculate the distance between the ultrasonic sensor and the object to be measured in real time based on the transit time, and judge whether the object to be measured is convex or concave according to the distance between the ultrasonic sensor and the object to be measured;

[0078] The primary echo peak value judgment module is used to judge the degree of protrusion or depression of the object under test by combining the change trend of the continuous primary echo peak values.

[0079] For relevant details, refer to the above method embodiment.

[0080] Fig.10 4 is a block diagram of an electronic device provided by an embodiment of the present application. The device at least includes a processor 401 and a memory 402.

[0081] The processor 401 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 401 may be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). The processor 401 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 401 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 401 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.

[0082] The memory 402 may include one or more computer-readable storage media, which may be non-transitory. The memory 402 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in the memory 402 is used to store at least one instruction, which is used to be executed by the processor 401 to implement the distance test based on the ultrasonic sensor module and the object contour recognition method provided in the method embodiment of the present application.

[0083] In some embodiments, the electronic device may further optionally include: a peripheral device interface and at least one peripheral device. The processor 401, the memory 402 and the peripheral device interface may be connected via a bus or a signal line. Each peripheral device may be connected to the peripheral device interface via a bus, a signal line or a circuit board. Schematically, the peripheral devices include but are not limited to: a radio frequency circuit, a touch display screen, an audio circuit, and a power supply.

[0084] Of course, the electronic device may also include fewer or more components, which is not limited in this embodiment.

[0085] Optionally, the present application also provides a computer-readable storage medium, in which a program is stored, and the program is loaded and executed by a processor to implement the distance test and object contour recognition method based on the ultrasonic sensor module of the above method embodiment.

[0086] Optionally, the present application also provides a computer product, which includes a computer-readable storage medium, in which a program is stored, and the program is loaded and executed by a processor to implement the distance test and object contour recognition method based on the ultrasonic sensor module of the above method embodiment.

[0087] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0088] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A distance test and object contour recognition method based on an ultrasonic sensor module, characterized in that: The method comprises: Applying a driving signal to the ultrasonic sensor to emit ultrasonic waves; Collect echo signals in real time and generate filtered signals; Counting the peak value and transit time of an echo from the filtered signal in real time; Calculating the distance between the ultrasonic sensor and the object to be measured in real time based on the transit time, and judging whether the object to be measured is convex or concave according to the distance between the ultrasonic sensor and the object to be measured; The degree of protrusion or depression of the object to be measured is determined by combining the changing trend of the continuous peak values ​​of the primary echoes.

2. The distance test and object contour recognition method based on the ultrasonic sensor module according to claim 1 is characterized in that: Applying a driving signal to the ultrasonic sensor to emit ultrasonic waves comprises: A driving signal is applied to both ends of the ultrasonic sensor probe to stimulate the sensor to emit ultrasonic waves. The driving signal is in the form of a bidirectional square wave, the driving frequency is 300kHz, the number of single waves is 5, the driving voltage is 10V, and the interval time of the driving waveform is 10ms.

3. The distance test and object contour recognition method based on the ultrasonic sensor module according to claim 1 is characterized in that: The real-time acquisition of echo signals and generation of filtered signals comprises: Performing bandpass filtering on the collected echo signal; Use dynamic noise floor detection method to identify the baseline of environmental noise, and restore the echo signal in combination with the filtering result; Output the processed filtered signal.

4. The distance test and object contour recognition method based on the ultrasonic sensor module according to claim 1 is characterized in that: The real-time counting of an echo peak value and a transit time from the filtered signal comprises: The ultrasonic sensor starts counting when it emits ultrasonic waves. After the ultrasonic waves are reflected by the object being measured, the ultrasonic receiving circuit detects the echo signal and amplifies and filters it. When the ultrasonic echo is identified, the counting stops at the same time. The value obtained by the counter at this time is the transit time.

5. The distance test and object contour recognition method based on the ultrasonic sensor module according to claim 1 is characterized in that: The real-time calculation of the distance between the ultrasonic sensor and the object to be measured based on the transit time, and judging whether the object to be measured is convex or concave according to the distance between the ultrasonic sensor and the object to be measured comprises: Based on the known ultrasonic propagation speed c, the distance D between the ultrasonic sensor and the object to be measured is calculated: D = c*t / 2.

6. The distance test and object contour recognition method based on the ultrasonic sensor module according to claim 5 is characterized in that: The calculating the distance between the ultrasonic sensor and the object to be measured in real time based on the transit time, and judging whether the object to be measured is a protrusion or a depression according to the distance between the ultrasonic sensor and the object to be measured further comprises: Determine the shape of the surface of the object being measured based on the distance change calculated in real time; If the detected distance increases, it means that the object being measured is concave; If the detected distance decreases, it means that the object being measured is a convexity; If the detected distance remains unchanged, it means that the object being measured is a plane.

7. The distance test and object contour recognition method based on the ultrasonic sensor module according to claim 1 is characterized in that: The step of judging the degree of protrusion or depression of the object under test by combining the changing trend of the peak values ​​of the continuous primary echoes includes: If there is a change difference between the peak values ​​of consecutive echoes, it means that the object being measured is a vertical protrusion / depression; If there is almost no change difference in the peak values ​​of consecutive echoes, it means that the object being measured is convex / concave at 45 degrees; Combined with the protrusions and depressions previously determined based on the distance, the outline of the object being measured is identified.

8. A distance test and object contour recognition system based on an ultrasonic sensor module, characterized in that: include: An ultrasonic transmitting module, used for applying a driving signal to the ultrasonic sensor to transmit ultrasonic waves; A filter signal generation module, used for real-time acquisition of echo signals and generation of filter signals; A data statistics module, used for real-time statistics of an echo peak value and a transit time from the filtered signal; A distance judgment module, used for calculating the distance between the ultrasonic sensor and the object to be measured in real time based on the transit time, and judging whether the object to be measured is convex or concave according to the distance between the ultrasonic sensor and the object to be measured; The primary echo peak value judgment module is used to judge the degree of protrusion or depression of the object under test based on the change trend of the continuous primary echo peak values.

9. An electronic device, characterized in that: The device includes a processor and a memory; a program is stored in the memory, and the program is loaded and executed by the processor to implement a distance test and object contour recognition method based on an ultrasonic sensor module as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The storage medium stores a program, and when the program is executed by the processor, it is used to implement a distance test and a contour recognition method of an object to be measured based on an ultrasonic sensor module as described in any one of claims 1 to 7.

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