Obstacle positioning method and device of multi-ultrasound head array

Abstract

The application provides a multi-probe array obstacle positioning method and device. The method comprises: in the case that multiple ultrasonic probes enter a transmitting mode of transmitting ultrasonic waves in turn and the multiple ultrasonic probes all enter a receiving mode of receiving ultrasonic waves, generating multi-dimensional time data corresponding to each transceiver pair; the transceiver pair comprises a pair of ultrasonic probes in the transmitting mode and an ultrasonic probe in the receiving mode; performing grid processing on the front area of the ultrasonic probe to obtain multiple grid points; determining a voting value corresponding to each grid point based on the multi-dimensional time data by using a spatial voting algorithm; and in the case that the voting value corresponding to the grid point is greater than a first threshold, determining positioning information of an obstacle based on the grid point. In this way, in a multi-obstacle scene, the positioning information of the obstacle can be confirmed by the voting values of the multiple grid points corresponding to the multiple grids in the front area of the ultrasonic probe, so that the purpose of accurate positioning and judgment in a multi-obstacle scene can be achieved.

Description

Technical Field

[0001] This application relates to the field of obstacle location technology, and in particular to an obstacle location method and apparatus using a multi-ultrasonic head array. Background Technology

[0002] Current ultrasonic ranging solutions are mainly divided into two types: single-transmitter / receiver and integrated transceiver. In the integrated transceiver solution, the sensor must wait for the aftershock to end after transmitting the signal before entering receiving mode, which leads to a large measurement blind zone. Furthermore, neither the single-transmitter / receiver nor the integrated transceiver solution can effectively handle the detection of multiple obstacles, especially in complex environments. These two solutions cannot accurately identify the positions of multiple obstacles, resulting in inaccurate localization and judgment in multi-obstacle scenarios. Therefore, how to achieve accurate ultrasonic localization in multi-obstacle environments remains a pressing technical challenge. Summary of the Invention

[0003] To address the aforementioned technical problems in the prior art, this application provides a method and apparatus for obstacle localization using a multi-ultrasound head array. This method can confirm the location information of obstacles in multi-obstacle scenarios by using the voting values ​​of grid points corresponding to multiple grids in the front area of ​​the ultrasonic head, thereby achieving accurate localization and judgment in multi-obstacle scenarios.

[0004] This application provides an obstacle localization method using a multi-ultrasound head array, comprising: generating multi-dimensional time data corresponding to each transceiver pair when multiple ultrasound heads take turns entering a transmission mode for emitting ultrasound and when all multiple ultrasound heads enter a reception mode for receiving ultrasound; wherein the multiple ultrasound head arrays are arranged such that each transceiver pair includes a pair of ultrasound heads in the transmission mode and an ultrasound head in the reception mode; performing gridding processing on the area in front of each ultrasound head to obtain multiple grid points; using a spatial voting algorithm to determine the voting value corresponding to each of the grid points based on the multi-dimensional time data; and determining obstacle localization information based on the grid points when the voting value corresponding to a grid point is greater than a first threshold.

[0005] In some embodiments, the method further includes: determining theoretical time data of a first transceiver pair corresponding to the obstacle based on the obstacle's location information; determining the location information as valid location information based on the theoretical time data and the multi-dimensional time data corresponding to the first transceiver pair and the second transceiver pair respectively; wherein the first transceiver pair and the second transceiver pair are reciprocal pairs.

[0006] In some embodiments, determining the positioning information as valid positioning information based on the theoretical time data and the multi-dimensional time data corresponding to the first and second transceiver pairs respectively includes: determining a first time measurement value that is closest to the theoretical time data in the multi-dimensional time data corresponding to the first transceiver pair; determining a second time measurement value that is closest to the theoretical time data in the multi-dimensional time data corresponding to the second transceiver pair; and determining the positioning information as valid positioning information based on the first and second time measurement values.

[0007] In some embodiments, generating multi-dimensional time data corresponding to each transmit / receive pair specifically includes: a first transmit code for OOK modulation under the current transmit cycle; controlling one of the plurality of ultrasonic heads to transmit ultrasonic waves using the first transmit code, and at least the remaining ultrasonic heads to receive ultrasonic waves in the receive mode to generate first detection information; and generating the multi-dimensional time data based on the first detection information.

[0008] In some embodiments, after generating the multi-dimensional time data based on the first detection information, the method further includes: determining that all the ultrasonic heads have completed transmission in the current transmission cycle, provided that there is a preset timeout period for the time data corresponding to the first detection information; determining a second transmission code for OOK modulation in the next transmission cycle; controlling one of the plurality of ultrasonic heads to transmit ultrasonic waves using the second transmission code, and controlling at least the remaining ultrasonic heads to receive ultrasonic waves in the receiving mode to generate second detection information, so as to generate the multi-dimensional time data based on the second detection information; wherein the first transmission code and the second transmission code are different transmission codes.

[0009] In some embodiments, generating the multi-dimensional time data based on the first detection information specifically includes: determining the cross-correlation calculation result between the first detection information and the transmission code; if the cross-correlation calculation result exceeds a third threshold, determining that the first detection information generated in the current transmission cycle is a valid signal, so as to generate the multi-dimensional time data based on the valid information.

[0010] In some embodiments, the step of using a spatial voting algorithm to determine the voting value of each grid point based on the multi-dimensional time data specifically includes: calculating the actual path distance corresponding to each time measurement value in the multi-dimensional time data; calculating the theoretical path distance between each grid point and the transmit / receive pair; and determining the voting value of each grid point based on the actual path distance and the theoretical path distance.

[0011] In some embodiments, determining the positioning information as valid positioning information based on the first time measurement value and the second time measurement value specifically includes: determining a reciprocity error parameter based on the difference between the first time measurement value and the second time measurement value; and determining the positioning information as valid positioning information if the reciprocity error parameter is less than a second threshold.

[0012] In some embodiments, after generating multi-dimensional time data corresponding to each transmit / receive pair, the method further includes: determining a first validity of the multi-dimensional time data corresponding to the transmit / receive pair based on the multi-dimensional time data corresponding to the two transmit / receive pairs that are calculated to be reciprocal; determining a second validity of the multi-dimensional time data corresponding to the ultrasonic head based on the correlation of the multi-dimensional time data corresponding to the ultrasonic head that has entered the transmission mode; and constructing an overdetermined linear equation system and a residual function based on the multi-dimensional time data that satisfies the first and second validity to determine the coordinate information of the obstacle.

[0013] This application embodiment also provides an obstacle localization device with a multi-ultrasound head array, including a generation module and a processing module. The generation module is used to generate multi-dimensional time data corresponding to each transceiver pair when multiple ultrasound heads take turns entering a transmission mode to emit ultrasound waves, and when all multiple ultrasound heads enter a reception mode to receive ultrasound waves; wherein the multiple ultrasound head arrays are arranged such that each transceiver pair includes a pair of ultrasound heads in the transmission mode and an ultrasound head in the reception mode. The processing module is used to perform gridding processing on the area in front of the ultrasound heads to obtain multiple grid points; to determine the voting value corresponding to each grid point based on the multi-dimensional time data using a spatial voting algorithm; and to determine the obstacle localization information based on the grid point if the voting value corresponding to a grid point is greater than a first threshold.

[0014] Compared with the prior art, the beneficial effects of the embodiments of this application are as follows: This application uses a multi-ultrasound head array arrangement, with multiple ultrasonic heads taking turns to enter the transmission mode of emitting ultrasonic waves, and all multiple ultrasonic heads entering the reception mode of receiving ultrasonic waves. That is, the mechanism of multiple ultrasonic heads emitting in turn and all ultrasonic heads receiving can realize the generation of multi-dimensional time data corresponding to each transmit-receive pair, and use a spatial voting algorithm to determine the voting value of each grid point based on the multi-dimensional time data, thereby determining the location information of the obstacle based on the voting value. In this way, in multi-obstacle scenarios, the location information of the obstacle can be confirmed by the voting value of the grid points corresponding to multiple grids in the front area of ​​the ultrasonic head, achieving the purpose of accurate positioning and judgment in multi-obstacle scenarios. It can be used in products such as lawnmowers and sweeping robots. Attached Figure Description

[0015] In drawings that are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The drawings generally illustrate various embodiments by way of example rather than limitation and are used, together with the description and claims, to illustrate the disclosed embodiments. Where appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and not intended to be exhaustive or exclusive embodiments of the apparatus or method.

[0016] Figure 1 This is a first flowchart of the obstacle localization method of the multi-ultrasonic head array according to an embodiment of this application.

[0017] Figure 2 This is a simplified diagram illustrating the application scenario of the obstacle localization method using a multi-ultrasonic head array according to an embodiment of this application.

[0018] Figure 3 This is a second flowchart of the obstacle localization method of the multi-ultrasonic head array according to an embodiment of this application.

[0019] Figure 4 This is the third flowchart of the obstacle localization method of the multi-ultrasonic head array according to the embodiments of this application.

[0020] Figure 5 This is the fourth flowchart of the obstacle localization method of the multi-ultrasonic head array according to the embodiments of this application.

[0021] Figure 6 The waveform diagram is for the OOK modulated signal with the first transmit code 1010.

[0022] Figure 7 The waveform output is obtained after receiving the first transmitted coded 1010 modulated signal and performing detection.

[0023] Figure 8 This is the fifth flowchart of the obstacle localization method of the multi-ultrasonic head array in the embodiments of this application.

[0024] Figure 9 This is the sixth flowchart of the obstacle localization method of the multi-ultrasonic head array in the embodiments of this application.

[0025] Figure 10 This is a structural block diagram of the obstacle positioning device of the multi-ultrasonic head array according to an embodiment of this application. Detailed Implementation

[0026] It should be understood that various modifications can be made to the embodiments described herein. Therefore, the above description should not be considered as limiting, but merely as an example of embodiments. Other modifications within the scope and spirit of this application will be apparent to those skilled in the art.

[0027] The accompanying drawings, which are included in and form part of this specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0028] These and other features of this application will become apparent from the following description of preferred forms of embodiments given as non-limiting examples, with reference to the accompanying drawings.

[0029] It should also be understood that although this application has been described with reference to some specific examples, those skilled in the art can certainly implement many other equivalent forms of this application.

[0030] The above and other aspects, features and advantages of this application will become more apparent when taken in conjunction with the accompanying drawings and in view of the following detailed description.

[0031] Specific embodiments of this application are described thereafter with reference to the accompanying drawings; however, it should be understood that the embodiments described are merely examples of this application, which may be implemented in various ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that could obscure the application. Therefore, the specific structural and functional details herein are not intended to be limiting, but merely to serve as the basis and representative basis for the claims to teach those skilled in the art to use this application in a variety of substantially any suitable detailed structures.

[0032] This specification may use the phrases “in one embodiment,” “in another embodiment,” “in yet another embodiment,” or “in other embodiments,” all of which may refer to one or more of the same or different embodiments according to this application.

[0033] This application provides an obstacle localization method using a multi-ultrasonic head array, which can be applied to products such as lawnmowers and sweeping robots.

[0034] like Figure 1 As shown, the obstacle localization method of multi-ultrasound head array includes steps S101 to S104.

[0035] Step S101: When multiple ultrasonic heads take turns entering the transmission mode of transmitting ultrasonic waves, and when all multiple ultrasonic heads enter the reception mode of receiving ultrasonic waves, multi-dimensional time data corresponding to each transceiver pair is generated; wherein, the multiple ultrasonic heads are arranged in an array, and the transceiver pair includes a pair of ultrasonic heads in the transmission mode and an ultrasonic head in the reception mode.

[0036] Multiple ultrasound heads (e.g., N ultrasound heads) can fill the short-range blind spots of transceiver ultrasound heads by cross-receiving data. For example... Figure 2As shown, the ultrasonic head can include an ultrasonic transducer and an ultrasonic transceiver chip. N ultrasonic heads transmit in turn. During each transmission, the non-transmitting ultrasonic heads are in receiving mode to acquire multipath time difference data. Of course, the ultrasonic head used for transmission can switch from transmitting mode to receiving mode after transmission to achieve reception via all ultrasonic heads.

[0037] Continue to combine Figure 2 To employ N transceiver ultrasonic heads (denoted as N transceiver ultrasonic heads) Taking an example, N ultrasonic heads are arranged horizontally with equal spacing d. The working cycle of an ultrasonic head can be understood as one cycle in which each ultrasonic head takes turns emitting ultrasonic waves during the emission phase, constituting a emission cycle. For example, if N is 4, the four ultrasonic heads work in emission mode sequentially within one emission cycle. In the i-th sub-cycle, the ultrasonic head... Transmit modulated ultrasonic waves. During the receiving phase: all ultrasonic heads... Enter receiving mode, where the ultrasonic head If the time it takes to receive the ultrasound wave exceeds the time blind zone (such as the time required for the ultrasound head to switch from transmitting mode to receiving mode), then the ultrasound head will be included. itself, such as an ultrasonic head If the received ultrasound wave occurs within the time blind zone, then the ultrasound head... The ultrasonic waves emitted this time could not be received.

[0038] It is understandable that not only the first echo is recorded, but also the preset timeout period. All effective reflection peak times within Where k is the echo sequence number, rx represents the time of echo reception, j is the sequence number of the receiving ultrasound head, and i is the sequence number of the transmitting ultrasound head. This generates multi-dimensional time data for each transmit / receive pair, such as an N×N multi-dimensional Time-of-Flight (ToF) matrix M (where N is the number of ultrasound heads), whose elements... It is a collection of timestamps.

[0039] Specifically, we can assume the obstacle is a point source reflection point P ( ), ultrasonic head The coordinates are Ultrasonic head The coordinates are If the speed of sound in an ultrasonic wave is v, then the ultrasonic head can be determined using the following formula. The emitted signal is reflected at point P and received by the ultrasonic head. Total path length received : .

[0040] The following example uses four ultrasound heads (N=4). When N=4, the ultrasound heads are arranged at equal intervals d, and the coordinates of the four ultrasound heads are as follows: :( 1.5d,0); :( 0.5d,0); :(0.5d,0); (1.5d,0). The 4×4 matrix M generated after one iteration is as follows: .

[0041] Step S102: The front area of ​​the ultrasonic head is meshed to obtain multiple mesh points.

[0042] Understandably, the area in front of the ultrasound head can be defined as the detection area, that is, the two-dimensional planar area in front of the ultrasound head. This detection area is discretized into a grid G ​​of size Δ×Δ (e.g., 2cm×2cm), and G can be expressed by the following formula: ; Where P is the number of discretized grid cells in the x-direction (forward direction); Q is the number of discretized grid cells in the y-direction (lateral direction).

[0043] Step S103: Use a spatial voting algorithm to determine the voting value for each grid point based on the multi-dimensional time data.

[0044] You can initialize the voting values ​​of all grid points. By calculating voting weights ,by Update the vote values ​​for each grid point.

[0045] For situations where there are multiple obstacles in the detection area (such as...) At that time, any pair of sender and receiver pairs Multiple time-of-flight (ToF) values ​​are received. By using a spatial voting algorithm, the real target can be separated from the cluttered signal, thus enabling the identification of multiple obstacles.

[0046] Step S104: If the voting value corresponding to the grid point is greater than the first threshold, determine the location information of the obstacle based on the grid point.

[0047] Understandably, all combinations of transmitting probe i and receiving probe j are iterated to determine the voting value corresponding to the multi-dimensional time data of each transmit / receive pair. A first threshold can be set. And extract local maxima grid points that satisfy the following conditions. : ; ; in, Represents grid points All grids within a certain surrounding range, i.e.: ; ; Where th is a preset value. This allows for the determination of multiple extreme points, at least one of which can be identified. The coordinates of this extreme point are the locations of the grid points where the multiple obstacles are calculated.

[0048] This application employs a multi-ultrasound head array arrangement, where multiple ultrasonic heads take turns emitting ultrasonic waves and simultaneously receive ultrasonic waves. This mechanism generates multi-dimensional time data for each transmit-receive pair. A spatial voting algorithm is then used to determine the voting value for each grid point based on this multi-dimensional time data. Based on these voting values, the location information of obstacles is determined. This allows for accurate location and judgment of obstacles in multi-obstacle scenarios by using the voting values ​​of grid points in the area in front of the ultrasonic heads. This technology can be used in products such as lawnmowers and robotic vacuum cleaners.

[0049] In some embodiments, such as Figure 3 As shown, the method further includes steps S201 to S202.

[0050] Step S201: Determine the theoretical time data of the first transmit / receive pair corresponding to the obstacle based on the obstacle's location information.

[0051] Step S202: Determine the positioning information as valid positioning information based on the theoretical time data and the multi-dimensional time data corresponding to the first and second transceiver pairs respectively; wherein the first and second transceiver pairs are reciprocal pairs.

[0052] Thus, by using theoretical time data determined by the location information of obstacles and multi-dimensional time data to determine whether the location information is valid, the validity of the location information can be accurately verified and calibrated. This method of using the reversibility of sound wave paths to eliminate multipath interference and false targets can improve positioning accuracy, reduce errors, and ensure that the location information is more reliable. In particular, it improves the accuracy and robustness of the method in complex environments or in the case of multiple obstacles.

[0053] Understandably, the reciprocal nature of the first and second transceiver pairs can be interpreted as follows: in the first transceiver pair, the first ultrasonic head acts as the transmitting probe, and the second ultrasonic head acts as the receiving probe; in the second transceiver pair, the second ultrasonic head acts as the transmitting probe, and the first ultrasonic head acts as the receiving probe. For example, the first transceiver pair could be... The second sender and receiver pair can be .

[0054] After determining the location information of the obstacles, a list of candidate obstacles can be determined. Each target Having coordinates For each candidate target Inverse calculation of its theoretical time data for any transmit / receive pair (i, j) .

[0055] In some embodiments, such as Figure 4 As shown, step S202, which determines the positioning information as valid positioning information based on the theoretical time data and the multi-dimensional time data corresponding to the first and second transceiver pairs respectively, specifically includes steps S301 to S303.

[0056] Step S301: Determine the first time measurement value that is closest to the theoretical time data from the multi-dimensional time data corresponding to the first transceiver pair.

[0057] Step S302: Determine the second time measurement value that is closest to the theoretical time data from the multi-dimensional time data corresponding to the second transceiver pair.

[0058] Step S303: Determine the positioning information as valid positioning information based on the first time measurement value and the second time measurement value.

[0059] In this way, the actual measurement value that is closest to the theoretical time data can be selected from multi-dimensional time data, thereby achieving accurate verification of the positioning information. This process ensures effective comparison between different transmitting and receiving pairs and enhances the reliability of the positioning results.

[0060] Understandably, when determining theoretical time data... Then, for any pair of ultrasonic heads (i, j), the measurement matrix can be used. Find the closest First time measurement value and in Find the closest Second time measurement .

[0061] In some embodiments, step S303, which determines the positioning information as valid positioning information based on the first time measurement value and the second time measurement value, specifically includes: determining a reciprocity error parameter based on the difference between the first time measurement value and the second time measurement value; and determining the positioning information as valid positioning information if the reciprocity error parameter is less than a second threshold.

[0062] In this way, the reciprocity error parameter can be obtained by calculating the difference between the first time measurement value and the second time measurement value. The positioning information is considered valid only when the error is less than the second threshold. The theoretical consistency that reciprocal transceivers should have can be used to verify the measurement results, thereby effectively identifying and filtering abnormal data caused by factors such as noise and environmental interference, and improving the reliability and accuracy of positioning information.

[0063] Understandably, this is in the process of determining the initial measurement value. Second time measurement value Next, the reciprocity error is calculated using the following formula to calculate the reciprocity error parameter. : .

[0064] exist If the time difference is less than the second threshold (e.g., 50 microseconds), the location information can be determined as valid location information, meaning the path is valid, the echo is a direct reflection, and the reciprocity check has been passed. In this case, the target can be retained. And can be used Update the measurements to eliminate the influence of wind speed.

[0065] exist If the location information is not less than the second threshold, it can be determined that the location information is not valid, meaning that the path has non-reciprocal interference (such as one-way obstruction, strong wind shear, etc.) and has failed the reciprocity check. In this case, the target location can be reduced. The confidence level.

[0066] Specifically, if the target If a data point passes the reciprocity check in more than half of the transmit / receive pairs, it is confirmed as a real obstacle; otherwise, it is marked as a false obstacle and discarded.

[0067] In some embodiments, such as Figure 5 As shown, the generation of multi-dimensional time data corresponding to each transmit / receive pair in step S101 specifically includes steps S401 to S403.

[0068] Step S401: Based on the first transmit code used for OOK (on / off keying) modulation in the current transmit cycle.

[0069] Step S402: Control one of the plurality of ultrasonic heads to emit ultrasonic waves in the first transmission code, and control at least the remaining ultrasonic heads to receive ultrasonic waves in the receiving mode to generate first detection information.

[0070] Step S403: Generate the multi-dimensional time data based on the first detection information.

[0071] In this way, by using OOK modulation transmission coding to control the ultrasonic head to transmit and receive in an orderly manner, the signal propagation time can be accurately captured, thereby generating multi-dimensional time data. This method can effectively improve the measurement resolution and anti-interference ability, provide high-precision and reliable basic data for subsequent positioning, and ensure the accuracy of positioning information.

[0072] The aforementioned first transmission code can be understood as the transmission sequence of ultrasonic waves emitted by the ultrasonic head, such as 1100, 1010, etc. Figure 6 and Figure 7 As shown, taking the first transmission code as 1100 as an example, Figure 6 The waveform of the OOK modulated signal with the first transmit code 1010 (m=8 in this example) is shown. The horizontal axis represents time, and the vertical axis represents the amplitude of the transmitted signal. Figure 7 The waveform output after receiving and detecting the above-mentioned coded and modulated signal is shown on the horizontal axis, which represents time, and the vertical axis represents the amplitude of the detected signal.

[0073] Understandably, different transmission codes can be used for different transmission cycles to determine different transmission codes under different transmission cycles, thereby facilitating the identification of each transmission cycle and distinguishing the multi-dimensional time data generated under different transmission cycles. Specifically, at least adjacent transmission cycles should use different transmission codes to avoid the inability to accurately identify adjacent transmission cycles.

[0074] In some embodiments, such as Figure 8 As shown, after generating the multi-dimensional time data based on the first detection information in step S403, the method further includes steps S501 to S503.

[0075] Step S501: Under the condition of a preset timeout time for the time data corresponding to the first detection information, determine that all the ultrasonic heads have completed the emission in the current emission cycle.

[0076] Step S502: Determine the second transmit code for OOK modulation in the next transmit cycle.

[0077] Step S503: Control one of the plurality of ultrasound heads to emit ultrasound waves in the second transmission code, and control at least the remaining ultrasound heads to receive ultrasound waves in the receiving mode to generate second detection information, and generate the multi-dimensional time data based on the second detection information; wherein the first transmission code and the second transmission code are different transmission codes.

[0078] In this way, by controlling the ultrasonic waves with different transmission codes to transmit and receive in multiple rounds, it is ensured that all ultrasonic heads can accurately complete transmission and acquire detection information in each transmission cycle. This not only effectively improves signal recognition capabilities and reduces interference, but also creates data diversity among multiple ultrasonic heads, thereby enhancing the accuracy and stability of multi-dimensional time data and providing more accurate and reliable data support for subsequent positioning. Furthermore, by setting a preset timeout T_max as the detection boundary, in conjunction with the coding mechanism, the effective detection field depth is defined while ensuring the detection frequency.

[0079] Understandably, the center frequency of the ultrasound can be set as... (e.g., 40kHz), one carrier cycle is The amplitude s(t) of the ultrasonic head when emitting ultrasonic waves is determined using the following formula: ; in, It is an encoded sequence of length L; The number of carrier cycles occupied by each bit (m=8 in this example); This is a rectangular window function.

[0080] In some embodiments, step S403, generating the multi-dimensional time data based on the first detection information, specifically includes: Determine the cross-correlation calculation result between the first detection information and the transmission code; If the cross-correlation calculation result exceeds the third threshold, the first detection information generated in the current transmission cycle is determined to be a valid signal, and the multi-dimensional time data is generated based on the valid information.

[0081] In this way, by calculating the cross-correlation result between the first detection information and the transmission code, and comparing the cross-correlation result with the third threshold, the validity of the first detection information can be effectively identified and verified, thereby ensuring the reliability and accuracy of the signal.

[0082] Understandably, if the current first transmission code is 1010, eight cycles of 40kHz pulses are transmitted first, followed by eight cycles of silence, and then the process is repeated. The receiving ultrasound head uses envelope detection to perform cross-correlation calculations on the detected first detection information (such as the envelope sequence) and the first transmission code. Only when the cross-correlation calculation result exceeds a third threshold is the first detection information generated in the current transmission cycle determined to be a valid signal.

[0083] In some embodiments, step S103, which involves using a spatial voting algorithm to determine the voting value for each grid point based on the multi-dimensional time data, specifically includes: Calculate the actual path distance corresponding to each time measurement value in the multi-dimensional time data; Calculate the theoretical path distance between each of the grid points and the transmit / receive pair; The voting value of each grid point is determined based on the actual path distance and the theoretical path distance.

[0084] Thus, by calculating the actual path distance corresponding to each time measurement and comparing it with the theoretical path distance, the validity of each grid point can be determined through a voting mechanism. This method effectively reduces errors caused by changes in the signal propagation environment by matching the actual and theoretical path distances, thereby improving positioning accuracy. The calculation of voting values ​​allows for the selection of the most reliable data points, enhancing adaptability to complex environments and improving the overall accuracy and stability of positioning.

[0085] It is understandable that for each valid time measurement in matrix M... (Where i is the transmitting ultrasound head and j is the receiving ultrasound head), calculate the corresponding actual path distance. .

[0086] For each grid point center coordinates The sum of the theoretical distances to ultrasound head i and ultrasound head j is calculated using the following formula: .

[0087] Furthermore, a Gaussian kernel function (or rectangular window function) is defined as the voting weight using the following formula: ; in, Let be the bandwidth, representing the system measurement error, typically around 1 cm. After calculating the voting weight w, use... Update the vote value for this grid point.

[0088] In some embodiments, such as Figure 9As shown, after generating multi-dimensional time data corresponding to each transmit / receive pair in step S101, the method further includes steps S601 to S603.

[0089] Step S601: Based on the multi-dimensional time data corresponding to the two transceiver pairs that are calculated as reciprocal pairs, determine the first validity of the multi-dimensional time data corresponding to the transceiver pairs.

[0090] Step S602: Based on the correlation of the multi-dimensional time data corresponding to the ultrasound head entering the transmission mode, determine the second validity of the multi-dimensional time data corresponding to the ultrasound head.

[0091] Step S603: Construct an overdetermined linear equation system and residual function based on multidimensional time data that satisfies the first and second validity requirements to determine the coordinate information of the obstacle.

[0092] In this way, overdetermined linear equations and residual functions can be used to further improve positioning accuracy, ensuring that the collected data undergoes rigorous validity screening, which helps to eliminate inaccurate or invalid data points and reduce the impact of errors.

[0093] The aforementioned first validity can be understood as validity related to matrix symmetry; theoretically, the path... With path They are completely equivalent, that is In actual algorithm processing, through calculation To reduce random errors caused by a single measurement (such as the influence of wind speed and environmental noise). If If the preset threshold is not exceeded, the corresponding multi-dimensional time data is determined to meet the first validity requirement; if... If the threshold is exceeded, the corresponding multi-dimensional time data is determined to not meet the first validity requirement, that is, the data set is judged as invalid interference signal and discarded.

[0094] The second effectiveness mentioned above can be understood as effectiveness related to blind spots, when the obstacle is extremely close (such as in...). When 5cm directly in front, Because the aftershocks were in a blind spot, but because... distance Let d be the signal it receives. Unaffected by aftershocks. At this time, after obtaining... , After obtaining the data, it can be determined that... and There is clearly no correlation, therefore it can be determined that It does not possess secondary validity. It possesses a second validity, which can be used to determine the coordinate information of obstacles, that is, by utilizing... (like Even with non-diagonal elements such as (which are available), it is still possible to detect a 0cm blind zone.

[0095] Understandably, for a single obstacle, with four ultrasonic heads, there are 16 measurements (after removing invalid and blind zone values, typically 10 to 12 valid values ​​remain, satisfying both primary and secondary validity criteria). At this point, let... For P to The distance can be used to establish the following system of equations: .

[0096] Therefore, the residual function is constructed. The Gauss-Newton iterative method is used to solve the residual function in order to determine the coordinate information of the obstacle more accurately.

[0097] This application also provides an obstacle location device 100 with a multi-ultrasonic head array. For example... Figure 10 As shown, the obstacle localization device 100 with a multi-ultrasound head array includes a generation module 101 and a processing module 102. The generation module 101 generates multi-dimensional time data corresponding to each transmit / receive pair when multiple ultrasound heads take turns entering a transmission mode for emitting ultrasound waves and when all multiple ultrasound heads enter a reception mode for receiving ultrasound waves. The multiple ultrasound head arrays are arranged such that each transmit / receive pair includes a pair of ultrasound heads in the transmission mode and an ultrasound head in the reception mode. The processing module 102 performs gridding processing on the area in front of the ultrasound heads to obtain multiple grid points; uses a spatial voting algorithm to determine the voting value corresponding to each grid point based on the multi-dimensional time data; and determines the obstacle's location information based on the grid point when the voting value corresponding to a grid point is greater than a first threshold.

[0098] This application employs a multi-ultrasound head array arrangement, where multiple ultrasonic heads take turns emitting ultrasonic waves and simultaneously receive ultrasonic waves. This mechanism generates multi-dimensional time data for each transmit-receive pair. A spatial voting algorithm is then used to determine the voting value for each grid point based on this multi-dimensional time data. Based on these voting values, the location information of obstacles is determined. This allows for accurate location and judgment of obstacles in multi-obstacle scenarios by using the voting values ​​of grid points in the area in front of the ultrasonic heads. This technology can be used in products such as lawnmowers and robotic vacuum cleaners.

[0099] In some embodiments, the processing module 102 is further configured to: determine the theoretical time data of the first transceiver pair corresponding to the obstacle based on the location information of the obstacle; determine the location information as valid location information based on the theoretical time data and the multi-dimensional time data corresponding to the first transceiver pair and the second transceiver pair respectively; wherein the first transceiver pair and the second transceiver pair are reciprocal pairs.

[0100] In some embodiments, the processing module 102 is further configured to: determine a first time measurement value that is closest to the theoretical time data in the multi-dimensional time data corresponding to the first transceiver pair; determine a second time measurement value that is closest to the theoretical time data in the multi-dimensional time data corresponding to the second transceiver pair; and determine the positioning information as valid positioning information based on the first time measurement value and the second time measurement value.

[0101] In some embodiments, the processing module 102 is further configured to: based on a first transmission code for OOK modulation in the current transmission cycle; control one of the plurality of ultrasound heads to transmit ultrasound waves using the first transmission code, and at least the remaining ultrasound heads to receive ultrasound waves in the receiving mode to generate first detection information; and generate the multidimensional time data based on the first detection information.

[0102] In some embodiments, the processing module 102 is further configured to: after generating the multi-dimensional time data based on the first detection information, determine that all the ultrasonic heads have completed transmission in the current transmission cycle, provided that the time data corresponding to the first detection information has a preset timeout period; determine a second transmission code for OOK modulation in the next transmission cycle; control one of the plurality of ultrasonic heads to transmit ultrasonic waves using the second transmission code, and control at least the remaining ultrasonic heads to receive ultrasonic waves in the receiving mode to generate second detection information, so as to generate the multi-dimensional time data based on the second detection information; wherein the first transmission code and the second transmission code are different transmission codes.

[0103] In some embodiments, the processing module 102 is further configured to: determine the cross-correlation calculation result between the first detection information and the transmission code; and if the cross-correlation calculation result exceeds a third threshold, determine that the first detection information generated in the current transmission cycle is a valid signal, so as to generate the multi-dimensional time data based on the valid information.

[0104] In some embodiments, the processing module 102 is further configured to: calculate the actual path distance corresponding to each time measurement value in the multi-dimensional time data; calculate the theoretical path distance between each grid point and the transmit / receive pair; and determine the voting value of each grid point based on the actual path distance and the theoretical path distance.

[0105] In some embodiments, the processing module 102 is further configured to: determine a reciprocity error parameter based on the difference between the first time measurement value and the second time measurement value; and determine the positioning information as valid positioning information if the reciprocity error parameter is less than a second threshold.

[0106] In some embodiments, the processing module 102 is further configured to: after generating multi-dimensional time data corresponding to each transmit / receive pair, determine a first validity of the multi-dimensional time data corresponding to the transmit / receive pair based on the multi-dimensional time data corresponding to the two transmit / receive pairs that are calculated as reciprocal pairs; determine a second validity of the multi-dimensional time data corresponding to the ultrasonic head based on the correlation of the multi-dimensional time data corresponding to the ultrasonic head that has entered the transmission mode; and construct an overdetermined linear equation system and a residual function based on the multi-dimensional time data that satisfies the first and second validity to determine the coordinate information of the obstacle.

[0107] Note that the various units in the embodiments of this application can be implemented as computer-executable instructions stored in memory, which, when executed by a processor, can perform corresponding steps; they can also be implemented as hardware with corresponding logical computing capabilities; or they can be implemented as a combination of software and hardware (firmware). In some embodiments, the processor can be implemented as any of an FPGA, ASIC, DSP chip, SOC (System-on-a-Chip), MPU (e.g., but not limited to Cortex), etc. The processor can be communicatively coupled to the memory and configured to execute computer-executable instructions stored therein. The memory can include read-only memory (ROM), flash memory, random access memory (RAM), dynamic random access memory (DRAM) such as synchronous DRAM (SDRAM) or Rambus DRAM, static memory (e.g., flash memory, static random access memory), etc., on which computer-executable instructions are stored in any format. The computer-executable instructions can be accessed by the processor, read from the ROM or any other suitable storage location, and loaded into the RAM for the processor to execute, to implement the wireless communication methods according to the embodiments of this application.

[0108] It should be noted that in the system of this application, the components are logically divided according to the functions they are to perform. However, this application is not limited to this and can re-divide or combine the components as needed. For example, some components can be combined into a single component, or some components can be further decomposed into more sub-components.

[0109] The various component embodiments of this application can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some or all of the components in the system according to the embodiments of this application. This application can also be implemented as a device or apparatus program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such a program implementing this application can be stored on a computer-readable medium or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form. Furthermore, this application can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means can be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0110] Furthermore, although exemplary embodiments have been described herein, their scope includes any and all embodiments based on this application that have equivalent elements, modifications, omissions, combinations (e.g., schemes involving intersections of various embodiments), adaptations, or alterations. Elements in the claims will be interpreted broadly based on the language used in the claims and are not limited to the examples described in this specification or during the implementation of this application, and such examples will be interpreted as non-exclusive.

[0111] The above description is intended to be illustrative and not restrictive. For example, the above examples (or one or more of them) can be used in combination with each other. Other embodiments can be used by those skilled in the art when reading the above description. Furthermore, in the above detailed description, various features may be grouped together to simplify the application. This should not be construed as an intention that a disclosed feature not claimed is necessary for any claim. Rather, the subject matter of the application may be less than all the features of a particular disclosed embodiment. Thus, the claims are incorporated herein by reference as examples or embodiments, wherein each claim is an independent, separate embodiment, and these embodiments are contemplated as being able to be combined with each other in various combinations or arrangements. The scope of this application should be determined by reference to the appended claims and the full scope of their equivalents.

[0112] The above embodiments are merely exemplary embodiments of this application and are not intended to limit this application. The scope of protection of this application is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to this application within its substance and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of this application.

Claims

1. A method for obstacle localization using a multi-ultrasonic head array, characterized in that, include: When multiple ultrasonic heads take turns entering the transmission mode of transmitting ultrasonic waves, and when all of the multiple ultrasonic heads enter the reception mode of receiving ultrasonic waves, multi-dimensional time data corresponding to each transceiver pair is generated; wherein, the multiple ultrasonic heads are arranged in an array, and the transceiver pair includes a pair of ultrasonic heads in the transmission mode and an ultrasonic head in the reception mode. The area in front of the ultrasonic head is meshed to obtain multiple mesh points; A spatial voting algorithm is used to determine the voting value for each grid point based on the multi-dimensional time data. If the vote value corresponding to the grid point is greater than the first threshold, the location information of the obstacle is determined based on the grid point.

2. The obstacle localization method of a multi-ultrasonic head array according to claim 1, characterized in that, The method further includes: Based on the location information of the obstacle, determine the theoretical time data of the first transmit / receive pair corresponding to it; The location information is determined to be valid location information based on the theoretical time data and the multi-dimensional time data corresponding to the first and second transceiver pairs, respectively; wherein the first and second transceiver pairs are reciprocal pairs.

3. The obstacle localization method of a multi-ultrasonic head array according to claim 2, characterized in that, The step of determining the location information as valid location information based on the theoretical time data and the multi-dimensional time data corresponding to the first and second transceiver pairs respectively includes: Determine the first time measurement value that is closest to the theoretical time data from the multi-dimensional time data corresponding to the first transceiver pair; Determine the second time measurement value that is closest to the theoretical time data from the multi-dimensional time data corresponding to the second transceiver pair; The location information is determined to be valid location information based on the first time measurement value and the second time measurement value.

4. The obstacle localization method of a multi-ultrasonic head array according to claim 1, characterized in that, The generation of multi-dimensional time data corresponding to each transmit / receive pair specifically includes: Based on the first transmit code used for OOK modulation in the current transmit cycle; Control one of the plurality of ultrasonic heads to emit ultrasonic waves in the first transmission code, and control at least the remaining ultrasonic heads to receive ultrasonic waves in the receiving mode to generate first detection information; The multi-dimensional time data is generated based on the first detection information.

5. The obstacle localization method of a multi-ultrasonic head array according to claim 4, characterized in that, After generating the multi-dimensional time data based on the first detection information, the method further includes: If a timeout period is preset for the time data corresponding to the first detection information, it is determined that all ultrasonic heads have completed emission in the current emission cycle; Determine the second transmit code to be used for OOK modulation in the next transmit cycle; One of the plurality of ultrasound heads is controlled to emit ultrasound waves in the second transmission code, and at least the remaining ultrasound heads are controlled to receive ultrasound waves in the receiving mode to generate second detection information, and the multidimensional time data is generated based on the second detection information; wherein the first transmission code and the second transmission code are different transmission codes.

6. The obstacle localization method of a multi-ultrasonic head array according to claim 4, characterized in that, The generation of the multi-dimensional time data based on the first detection information specifically includes: Determine the cross-correlation calculation result between the first detection information and the transmission code; If the cross-correlation calculation result exceeds the third threshold, the first detection information generated in the current transmission cycle is determined to be a valid signal, and the multi-dimensional time data is generated based on the valid information.

7. The obstacle localization method of a multi-ultrasonic head array according to claim 1, characterized in that, The process of determining the voting value for each grid point based on the multi-dimensional time data using a spatial voting algorithm specifically includes: Calculate the actual path distance corresponding to each time measurement value in the multi-dimensional time data; Calculate the theoretical path distance between each of the grid points and the transmit / receive pair; The voting value of each grid point is determined based on the actual path distance and the theoretical path distance.

8. The obstacle localization method of a multi-ultrasonic head array according to claim 3, characterized in that, The step of determining the location information as valid location information based on the first time measurement value and the second time measurement value specifically includes: Based on the difference between the first time measurement value and the second time measurement value, the reciprocity error parameter is determined; If the reciprocity error parameter is less than the second threshold, the positioning information is determined to be valid positioning information.

9. The obstacle localization method of a multi-ultrasonic head array according to claim 1, characterized in that, After generating the multi-dimensional time data corresponding to each transmit / receive pair, the method further includes: The first validity of the multi-dimensional time data corresponding to the two transceiver pairs that are reciprocal is determined based on the calculation. Based on the correlation of the multi-dimensional time data corresponding to the ultrasonic head when it enters the emission mode, the second validity of the multi-dimensional time data corresponding to the ultrasonic head is determined. Based on multi-dimensional time data that satisfies the first and second validity requirements, an overdetermined linear equation system and a residual function are constructed to determine the coordinate information of the obstacle.

10. An obstacle positioning device with a multi-ultrasonic head array, characterized in that, include: A generation module is used to generate multi-dimensional time data corresponding to each transceiver pair when multiple ultrasonic heads take turns entering the transmission mode of transmitting ultrasonic waves and when all multiple ultrasonic heads enter the reception mode of receiving ultrasonic waves; wherein, the multiple ultrasonic heads are arranged in an array, and the transceiver pair includes a pair of ultrasonic heads in the transmission mode and an ultrasonic head in the reception mode. The processing module is used to perform gridding processing on the front area of ​​the ultrasonic head to obtain multiple grid points; A spatial voting algorithm is used to determine the voting value for each grid point based on the multi-dimensional time data. If the vote value corresponding to the grid point is greater than the first threshold, the location information of the obstacle is determined based on the grid point.

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