Tracking method and system thereof

Abstract

A method for tracking a movement, characterized in that the method includes: receiving a first sound signal corresponding to a user's first footstep; calculating a first position corresponding to the first footstep based on the relative position relationship of three microphones and the time difference of the three microphones receiving the first sound source; receiving a second sound signal corresponding to the user's second footstep; and calculating a second position corresponding to the second footstep based on the first position, the time difference between receiving the first sound signal and the second sound signal, the sound receiving angle between the first sound signal and a pair of microphones in the microphone array, and the sound receiving angle between the second sound signal and the pair of microphones. The present invention also provides a system for tracking a movement. The present invention can quickly execute footsteps based on step length and moving angle.

Description

Technical Field

[0001] The present invention relates to a trajectory tracking method and system, and particularly to a trajectory tracking method and system for tracking the movement direction according to the subsequent step distance and the change of the sound reception angle after the first step of the user is located. Background Art

[0002] In the prior art, sensors are usually used to monitor the movement of users, and at the same time, the footstep frequency and intensity of the person are collected by listening to combine relevant data to achieve the purpose of identifying the movement. However, in order to accurately monitor the movement direction of the user, multiple sensors must be arranged in the surrounding environment for monitoring, which requires more cost. Therefore, how to achieve the purpose of identifying different users and locating the sound of footsteps at a lower cost is the problem to be solved currently. Summary of the Invention

[0003] In view of this, there is a need for a trajectory tracking method and system that can track the movement direction of different users only by using a microphone array.

[0004] The present invention provides a trajectory tracking method, characterized in that the method includes: receiving, through a microphone array, a first sound signal corresponding to the first footstep of a user; calculating, through a processing module, a first position corresponding to the first footstep according to the relative position relationship of at least three microphones in the microphone array and the time difference of arrival of the first sound source received by the three microphones respectively; receiving, through the microphone array, a second sound signal corresponding to the second footstep of the user, wherein the audio of the second sound signal is the same as the audio of the first sound signal; and calculating, through the processing module, a second position corresponding to the second footstep according to the first position, the time difference between receiving the first sound signal and the second sound signal, the sound reception angle between the first sound signal and a pair of microphones in the three microphones, and the sound reception angle between the second sound signal and the pair of microphones.

[0005] The present invention also provides a trajectory tracking system, characterized in that the system includes a microphone array and a processing module. The microphone array is composed of at least three microphones, and is used to receive a first sound signal corresponding to the first footsteps of a user and a second sound signal corresponding to the second footsteps of the user, wherein the audio of the second sound signal is the same as the audio of the first sound signal. The processing module is used to calculate a first position corresponding to the first footsteps according to the relative position relationship of the three microphones and the time difference of arrival of the first sound source received by the three microphones, and calculate a second position corresponding to the second footsteps according to the first position, the time difference between receiving the first sound signal and the second sound signal, the sound receiving angle between the first sound signal and a pair of microphones in the microphone array, and the sound receiving angle between the second sound signal and the pair of microphones.

[0006] According to an embodiment of the present invention, when the difference between the sound receiving angles of the first sound signal and the pair of microphones and the sound receiving angles of the second sound signal and the pair of microphones is equal to 0 or less than a predetermined value, the second position is equal to the first position.

[0007] According to another embodiment of the present invention, the processing module further selects different step distances according to the magnitude of the time difference between receiving the first sound signal and the second sound signal.

[0008] According to another embodiment of the present invention, the microphone array has five microphones, and the microphone array is in a regular pentagon shape, and the distance between every two adjacent microphones is 20 millimeters. Description of the Drawings

[0009] Figure 1 It is a block diagram of the trajectory tracking system according to an embodiment of the present invention.

[0010] Figure 2 It is a schematic diagram of the microphone array 110 according to an embodiment of the present invention.

[0011] Figure 3 It is a schematic diagram of user positioning according to an embodiment of the present invention.

[0012] Figure 4a 、 4b It is a schematic diagram of calculating the position of the second step according to an embodiment of the present invention.

[0013] Figure 5 It is a flowchart of the trajectory tracking method according to an embodiment of the present invention.

[0014] Description of the Main Element Symbols

[0015] Trace Tracking System 100

[0016] Microphone Array 110

[0017] Processing Module 120

[0018] Storage Module 130

[0019] Microphones 201 - 205

[0020] Positioning Curves L1, L2

[0021] Sound Reception Angles θa1, θa2, θb1, θb2

[0022] Angle Difference θab

[0023] Step Distance Lab

[0024] Step Processes S501 to S506 Detailed Implementation Manner

[0025] Other scopes applicable to the system and method of the present invention will be clearly visible in the detailed description provided next. It must be understood that the following detailed description and specific embodiments, when presenting exemplary embodiments of the trace tracking method and its system, are only for the purpose of description and not for limiting the scope of the present invention.

[0026] Figure 1 FIG. is a block diagram of a trace tracking system 100 according to an embodiment of the present invention. The trace tracking system 100 at least includes a microphone array 110, a processing module 120, and a storage module 130. The microphone array 110 is at least composed of three microphones arranged at different positions for receiving sound signals corresponding to different sound sources from various directions. The processing module 120 is used to receive sound signals from the microphone array 110 and determine the sound source position based on the relative position relationship between every two microphones in the microphone array 110, the time and angle of receiving the sound signals, and the characteristics of the sound signals. Among them, the processing module 110 can be, for example, a dedicated hardware circuit or general hardware (such as a single processor, a multi-processor with parallel processing capabilities, a graphics processor, or other processors with computing capabilities), and when executing the program code or software, it provides the functions described later. The storage module 130 can be a non-volatile storage device such as a hard disk or a USB flash drive, used to store the position of each microphone in the microphone array 110, the relative position relationship between every two adjacent microphones, the sound frequencies corresponding to various different types of sound sources, and various algorithms required during the execution of the calculation process, etc., for the processing module 120 to access. Among them, if the object emitting the sound source is a human, it can be determined whether it belongs to the same user according to the sound frequencies emitted by different types of shoes and / or the weight of the footsteps.

[0027] Figure 2 Schematic diagram of the microphone array 110 according to an embodiment of the present invention. In an example of the present invention, the microphone array 110 is composed of microphones 201-205 and is in the shape of a regular pentagon. Among them, the distance between every two adjacent microphones (that is, the distances between microphone 201 and microphone 202, microphone 202 and microphone 203, microphone 203 and microphone 204, microphone 204 and microphone 205, and microphone 205 and microphone 201 respectively) is 20 millimeters. It should be noted that Figure 2 The shown regular pentagon microphone array is only a preferred embodiment, but is not limited to the regular pentagon, and the distance between every two adjacent microphones can also be customized by the user.

[0028] Figure 3 Schematic diagram of user positioning according to an embodiment of the present invention. First, when the processing module 120 receives the sound signal corresponding to the user's current footsteps through the microphone array 110, it first analyzes the audio corresponding to the footsteps from the sound signal to determine whether the audio corresponding to this set of footsteps has appeared before. However, when the audio corresponding to the current footsteps has not appeared within a predetermined time (for example, within the previous 5 seconds), the processing module 120 determines that this user has first stepped into the sound collection range of the microphone array 110 or has been standing at a fixed point without moving for a long time, and then uses the Time Difference of Arrival (TDOA) positioning technology to determine the user's current position. For example, as Figure 3 shown, when the user's footsteps appear at point a and the audio corresponding to the footsteps has never appeared, since the distances from point a to microphones 201, 202, and 205 are all different, the processing module 120 can obtain the hyperbolas L1 and L2 corresponding to microphones 201, 202 and microphones 201, 205 respectively according to the time difference of sound arrival at microphones 201, 202, and 205, and the intersection point a of the hyperbolas L1 and L2 is the position corresponding to the user's footsteps.

[0029] Next, after calculating the position corresponding to point a, the processing module 120 further calculates the sound collection included angle between the pair of microphones in the microphone array 110 that is closest to it, as a basis for judging the user's subsequent movement state. For example, as Figure 4aAs shown, after obtaining the position of point a, the two microphones closest to point a are microphone 201 and microphone 202. The processing module 120 then obtains the sound reception angle θa1 of point a corresponding to microphone 201 and the sound reception angle θa2 of point a corresponding to microphone 202, and stores them in the storage module 130. Then, when the processing module 120 receives the sound signal corresponding to the user's next footstep through the microphone array 110 (for example, by judging the audio and / or volume corresponding to the footstep), the processing module 120 further calculates the sound reception angle θb1 of this footstep corresponding to microphone 201 and the sound reception angle θb2 corresponding to microphone 202 (as shown in Figure 4b ). Then, the processing module 120 can judge the movement track of the user according to the angle and the step distance. Among them, the step distance can be deduced according to the time difference between the user's current footstep and the previous footstep. For example, when the time difference is less than 1.5 steps per second, it means that the user is walking at a slower speed, and the corresponding step distance is usually shorter (for example, 70 cm). When the time difference is 1.5 - 2 steps per second, it means that the user is walking at a normal speed, and the corresponding step distance is about 85 cm. However, when the time difference is more than 2 steps per second, it means that the user is power walking, and the corresponding step distance will be larger, usually about 100 cm. In other words, the faster the walking speed (that is, the shorter the distance between footsteps), the larger the step distance. It should be noted that the foregoing step distance is obtained according to the walking speed of ordinary adults, and it can be corrected according to different ages, and is not limited thereto.

[0030] According to an embodiment of the present invention, when the difference between the angle θa1 and the angle θb1 and the difference between the angle θa2 and the angle θb2 are 0 or less than a predetermined value (for example, less than 5 degrees), it means that the user is standing still and not moving, then the processing module 120 judges that the user's current position is the same as the previous position. On the contrary, when the difference between the angle θa1 and the angle θb1 and the difference between the angle θa2 and the angle θb2 are greater than the predetermined value (that is, greater than 5 degrees), it means that the user is in a moving state, and the processing module 120 can then find the position corresponding to point b according to the coordinates corresponding to point a, the previously calculated sound reception angles θa1, θb1, θa2, θb2 and the step distance. For example, as shown in Figure 4b , after calculating the included angle θab, the coordinates of point b (Xb, Yb) = (Xa + Lab * Sinθab, Ya + Lab * Cosθab) can be obtained according to the coordinates (Xa, Xb) of point a. Among them, Lab is the step distance described in the previous paragraph. By analogy, when the user walks within the sound reception range of the microphone array 110, the movement track of the user can be traced through the foregoing method.

[0031] Figure 5A flowchart of a trajectory tracking method according to an embodiment of the present invention. In step S501, the microphone array 110 receives a current sound signal corresponding to the user's current footsteps and outputs the corresponding current sound signal to the processing module. In step S502, the processing module 120 analyzes the audio corresponding to the current sound signal and determines whether a sound signal with the same audio has occurred within a predetermined time. If a sound signal with the same audio has not been received within the predetermined time, it proceeds to step S503, and the processing module 120 calculates the current position corresponding to the user's current footsteps based on the relative position relationship of at least three microphones in the microphone array and the time difference of arrival of the sound signals received by the three microphones respectively. Conversely, if the microphone array 110 has received a sound signal with the same audio within the predetermined time, it proceeds to step S504, and the processing module 120 obtains the step length based on the time difference between the current sound signal corresponding to the current footsteps and the previous sound signal corresponding to the previous footsteps. In step S505, the processing module calculates the current position corresponding to the current footsteps based on the step length, the angles at which at least two microphones in the microphone array receive the current sound source, and the previous position corresponding to the previous footsteps. Among them, when the angle at which the microphone receives the current sound source is the same as the angle at which the microphone receives the previous sound source, the processing module determines that the user is only standing still in place, that is, the current position is the same as the previous position.

[0032] It should be noted that although the above method has been described based on a flowchart of a series of steps or blocks, the present invention is not limited to the order of these steps, and some steps may be executed in a different order from the remaining steps or the remaining steps may be performed simultaneously. In addition, those skilled in the art will understand that the steps shown in the flowchart are not the only ones, and it may include other steps of the flowchart, or one or more steps may be deleted without affecting the scope of the present invention.

[0033] In summary, according to the trajectory tracking method and system proposed by some embodiments of the present invention, after obtaining the position corresponding to the first footsteps of the user through the time difference of arrival positioning technology, the movement trajectory of the user can be calculated by monitoring the time difference and the sound reception angle of the subsequent footsteps of the user. In this way, the purpose of positioning the user's position can be achieved only through a microphone array. In addition, by identifying the audio of the shoes corresponding to the footsteps to distinguish different users, multiple users can also be positioned simultaneously without the need for additional sensors, thereby reducing the cost of monitoring.

[0034] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for tracking a path, characterized in that: The method comprises: receiving a first sound signal corresponding to a first footstep of a user through a microphone array; Calculating a first position corresponding to the first footstep sound through a processing module according to a relative position relationship of at least three microphones in the microphone array and a time difference of arrival of the first sound signal received by the three microphones; receiving a second sound signal corresponding to a second footstep of the user through the microphone array, wherein the audio of the second sound signal is the same as the audio of the first sound signal; and The second position corresponding to the second footsteps is calculated through the processing module according to the first position, the time difference between receiving the first sound signal and the second sound signal, the sound pickup angle between the first sound signal and a pair of microphones among the three microphones, and the sound pickup angle between the second sound signal and the pair of microphones, wherein when the difference between the sound pickup angle between the first sound signal and the pair of microphones and the sound pickup angle between the second sound signal and the pair of microphones is equal to 0 or less than a predetermined value, the processing module determines that the second position is the same as the first position, and the movement state of the user is standing still without moving, and when the difference between the sound pickup angle between the first sound signal and the pair of microphones and the sound pickup angle between the second sound signal and the pair of microphones is greater than a predetermined value , the processing module further determines the movement state of the user according to the sound pickup angle and the stride, wherein the stride is derived according to the time difference between the second sound signal and the first sound signal received, when the time difference is less than the first step per second, the processing module determines that the movement state of the user is slow walking, and the stride is the first distance, when the time difference is from the first step per second to the second step per second, the processing module determines that the movement state of the user is normal speed walking, and the stride is the second distance, when the time difference is greater than the second step per second, the processing module determines that the movement state of the user is brisk walking, and the stride is the third distance, wherein the second step is greater than the first step, the third distance is greater than the second distance, and the second distance is greater than the first distance; and The processing module calculates the coordinates of the second position according to the coordinates corresponding to the first position, the sound pickup angle between the first sound signal and a pair of the three microphones, the sound pickup angle between the second sound signal and the pair of microphones, and the step distance to track the movement trajectory of the user's movement state.

2. The method for tracking a path according to claim 1, characterized in that: The microphone array has five microphones, and the microphone array is in a regular pentagonal shape, and the distance between every two adjacent microphones is 20 mm.

3. A tracking system, characterized in that: The system comprises: a microphone array, comprising at least three microphones, for receiving a first sound signal corresponding to a first footstep of a user and a second sound signal corresponding to a second footstep of the user, wherein the audio of the second sound signal is the same as the audio of the first sound signal; and A processing module, used for calculating a first position corresponding to the first footsteps according to the relative position relationship of the three microphones and the time difference of the sound arrival of the first sound signal received by the three microphones, and calculating a second position corresponding to the second footsteps according to the first position, the time difference of receiving the first sound signal and the second sound signal, the sound pickup angle between the first sound signal and a pair of microphones in the microphone array, and the sound pickup angle between the second sound signal and the pair of microphones, wherein when the difference between the sound pickup angle between the first sound signal and the pair of microphones and the sound pickup angle between the second sound signal and the pair of microphones is equal to 0 or less than a predetermined value, the processing module determines that the second position is the same as the first position, and the movement state of the user is standing still without moving; when the sound pickup angle between the first sound signal and the pair of microphones is equal to 0 or less than a predetermined value, the processing module determines that the second position is the same as the first position, and the movement state of the user is standing still without moving; When the difference between the second sound signal and the sound pickup angle of the pair of microphones is greater than a predetermined value, the processing module also determines the user's movement state based on the sound pickup angle and the step length, wherein the step length is deduced based on the time difference between the second sound signal and the first sound signal received, when the time difference is less than the first step per second, the processing module determines the user's movement state as slow walking and the step length as the first distance, when the time difference is between the first step and the second step per second, the processing module determines the user's movement state as normal walking and the step length as the second distance, and when the time difference is greater than the second step per second, the processing module determines the user's movement state as brisk walking and the step length as the third distance, wherein the second step number is greater than the first step number, the third distance is greater than the second distance, and the second distance is greater than the first distance; and The processing module further calculates the coordinates of the second position according to the coordinates corresponding to the first position, the sound pickup angle between the first sound signal and a pair of the three microphones, the sound pickup angle between the second sound signal and the pair of microphones, and the step distance to track the movement trajectory of the user's movement state.

4. The tracking system according to claim 3, characterized in that: The microphone array has five microphones, and the microphone array is in a regular pentagonal shape, and the distance between every two adjacent microphones is 20 mm.

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