Table tennis landing area detection method, rally calculation method, and table tennis table

Abstract

The application provides a table tennis landing point area detection method, a round calculation method and a table tennis table. The detection method comprises the following steps: arranging a left IMU and a right IMU on the table tennis table; collecting data of the left IMU and the right IMU, obtaining three-dimensional acceleration and three-dimensional angular velocity at each sampling time and storing the three-dimensional acceleration and three-dimensional angular velocity; performing frequency domain analysis on N1 latest acceleration and angular velocity data stored to determine whether the data is the data of a table tennis ball colliding with the table tennis table; if yes and the landing point area of the table tennis ball on the table tennis table needs to be obtained, arranging more than three vibration sensors on the left half table tennis table and the right half table tennis table; collecting data of the vibration sensors to obtain high and low level signals at each sampling time; determining the position coordinates of the collision point on the table tennis table by using a time difference positioning principle; and determining the final landing point area of the table tennis ball according to the principle of minority submitting to majority. The application can conveniently and quickly obtain the landing point area of the table tennis ball on the table tennis table.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of table tennis landing point detection, and particularly relates to a table tennis landing point area detection method, a round calculation method and a table tennis table. BACKGROUND

[0002] Table tennis is a popular ball sport in the world, and is also a sport that men, women and the old and young all like very much. From the aspect of table tennis technology, the landing point position of table tennis is very important, which directly reflects the technical level of a trainer. Proficiently mastering the landing point and landing technology of table tennis is the key to mastering the table tennis skill. However, in the prior art, the landing point area of table tennis on the table cannot be accurately detected, and can only be judged by the naked eyes of the trainer, which is not conducive to the improvement of the technical level of the trainer. SUMMARY

[0003] In order to at least partially overcome the problems in the related art, the application provides a table tennis landing point area detection method, a round calculation method and a table tennis table.

[0004] According to a first aspect of the embodiments of the application, the application provides a table tennis landing point area detection method, which comprises the following steps:

[0005] A left IMU is arranged on the left half table, and a right IMU is arranged on the right half table;

[0006] The left IMU and the right IMU are respectively subjected to data acquisition with a sampling period T1, and three-dimensional acceleration and three-dimensional angular velocity at each sampling time are obtained and stored;

[0007] N1 latest acceleration and angular velocity data are selected from the stored three-dimensional acceleration and three-dimensional angular velocity with a detection time window T3 at each sampling time, and frequency domain analysis is performed to determine whether the N1 latest acceleration and angular velocity data are data of a table tennis ball colliding with the table;

[0008] If the data are data of a table tennis ball colliding with the table, it is determined whether a vibration sensor needs to be arranged on the left half table and the right half table according to whether the landing point area of the table tennis ball on the table needs to be acquired;

[0009] If the landing point area of the table tennis ball on the table needs to be acquired, N vibration sensors need to be arranged on the left half table and the right half table, where N≥3;

[0010] The vibration sensors on the left half table and the right half table are respectively subjected to data acquisition with a sampling period T2, and high-low level signals at each sampling time are obtained;

[0011] Obtaining N2 level data of all vibration sensors of the left half table or the right half table in the detection time window T3, determining the starting along time of each vibration sensor; traversing all combinations of time difference of 3 vibration sensors not in a line in the N vibration sensors, and determining the position coordinates of the collision point on the table by using the time difference positioning principle;

[0012] Counting the position coordinates of the landing points of the M vibration sensor combinations in the set area, and determining the final landing point area of the table tennis ball according to the principle of minority serving majority.

[0013] In the above table tennis landing point area detection method, if the N1 latest acceleration and angular velocity data are not the data of the collision of the table tennis ball with the table, then the left IMU and the right IMU are re-acquired with the sampling period T1, respectively, to obtain the three-dimensional acceleration and three-dimensional angular velocity at each sampling time and store them.

[0014] In the above table tennis landing point area detection method, if the landing point area of the table tennis ball on the table is not needed, then the collision detection of the table tennis ball with the left half table is completed by the left IMU or the collision detection of the table tennis ball with the right half table is completed by the right IMU.

[0015] In the above table tennis landing point area detection method, the process of determining the position coordinates of the collision point on the table by using the time difference positioning principle is as follows:

[0016] Supposing that the position coordinates of the 3 vibration sensors in a time difference combination on the table plane are (x s1 ,y s1 ), (x s2 ,y s2 ) and (x s3 ,y s3 ), and the position coordinates of the collision point P d of the table tennis ball with the table are (x d ,y d ), then the distance r1 between the collision point and the first vibration sensor is:

[0017]

[0018] The distance r2 between the collision point and the second vibration sensor is:

[0019]

[0020] The distance r3 between the collision point and the third vibration sensor is:

[0021]

[0022] The difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the second vibration sensor is calculated.21 And the difference r between the distance r from the collision point to the first vibration sensor and the distance r from the collision point to the third vibration sensor. 31 ; where r 21 =r2-r1,r 31 =r3-r1;

[0023] Based on the distance r1 between the collision point and the first vibration sensor, and the difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the second vibration sensor. 21 The collision point position vector was calculated. The position coordinates (x, y) of the three vibration sensors on the table plane s1 ,y s1 ), (x s2 ,y s2 ) and (x s3 ,y s3 The relationship between )

[0024]

[0025]

[0026] In the formula, x d21 The x-axis represents the positional difference between the second vibration sensor and the first vibration sensor in the X-axis direction. d21 =x s2 -x s1 ;y d21 This represents the position difference between the second vibration sensor and the first vibration sensor in the Y-axis direction, y d21 =y s2 -y s1 ;x d31 The x-axis represents the positional difference between the third vibration sensor and the first vibration sensor in the X-axis direction. d31 =x s3 -x s1 ;y d31 This represents the position difference between the third vibration sensor and the first vibration sensor in the Y-axis direction, y d31 =y s3 -y s1 K1 represents the modulus at the location of the first vibration sensor. K2 represents the modulus at the location of the second vibration sensor. K3 represents the modulus at the location of the third vibration sensor.

[0027] For the collision point position vector The position coordinates (x, y) of the three vibration sensors on the table plane s1 ,y s1 ), (x s2 ,ys2 ) and (x s3 , y s3 ) is simplified as:

[0028]

[0029] wherein matrix M P1 , M P2 and M P3 are respectively

[0030] According to the simplified expression of the position vector and the coordinates of the first vibration sensor, the vector of the collision point pointing to the first vibration sensor is:

[0031]

[0032] wherein P s1 represents the vector of the position coordinates of the first vibration sensor on the billiard table plane,

[0033] According to the expression of the distance r1 between the collision point and the first vibration sensor, we have:

[0034]

[0035] According to the vector of the collision point pointing to the first vibration sensor and the expression of r1 2 , we have:

[0036]

[0037] wherein, B = 2T P2 T (T P3 -P s1 ), C = (T P3 -P s1 ) 2 ; T P2 = M P1 M P2 , T P3 = M P1 · M P3 ;

[0038] By substituting the value of r1 into the expression , the position coordinates of the collision point P d on the billiard table are obtained.

[0039] Further, the difference r 21and the difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the third vibration sensor 31 obtained by the time difference of vibration transmission,

[0040] In the formula, V c represents the propagation speed of vibration on the table, t d21 represents the time difference of vibration transmission of the first vibration sensor and the second vibration sensor, t d31 represents the time difference of vibration transmission of the first vibration sensor and the third vibration sensor,

[0041] In the formula, t1, t2 and t3 respectively represent the starting time of the first vibration sensor, the second vibration sensor and the third vibration sensor.

[0042] In the above method for detecting the landing area of a table tennis ball, the relationship between the number M of vibration sensor combinations and the number N of vibration sensors is:

[0043]

[0044] In the formula, C represents the number of combinations.

[0045] According to a second aspect of the embodiments of the present application, the present application provides a method for calculating the round of a table tennis ball, which comprises the following steps:

[0046] The landing point information sequence of the table tennis ball at each time is obtained by using the method for detecting the landing area of a table tennis ball according to any one of the above.

[0047] It is judged whether the landing points at adjacent times appear alternately in the areas on the left half table and the right half table. If yes, the number of rounds is accumulated.

[0048] According to a third aspect of the embodiments of the present application, the present application provides a table tennis table, which comprises a table body and an electric control assembly. The table body comprises a left half table and a right half table. The electric control assembly comprises a left IMU, a left vibration sensor, a right IMU, a right vibration sensor and an MCU.

[0049] The left IMU and the left vibration sensor are arranged on the left half table, and the right IMU and the right vibration sensor are arranged on the right half table. The left IMU and the right IMU are connected with the MCU, and the left vibration sensor and the right vibration sensor are connected with the MCU.

[0050] The MCU is used to realize each step in the method for detecting the landing area of a table tennis ball according to any one of the above.

[0051] In the above table tennis table, the MCU is further used to realize each step in the method for calculating the round of a table tennis ball.

[0052] The table further comprises a Bluetooth module, which is connected with the MCU, and the MCU communicates with the application terminal or the Bluetooth remote controller through the Bluetooth module.

[0053] According to the above specific embodiments of the present application, at least the following beneficial effects are obtained: the table provided by the present application can detect the landing area of the table tennis ball through the IMU to collect three-dimensional acceleration and three-dimensional angular velocity, and analyze the latest acceleration and angular velocity data to determine whether it is the data of the collision between the table tennis ball and the table; for the data of the collision between the table tennis ball and the table, the vibration sensor is further set to determine the position coordinates of the collision point on the table tennis table by using the time difference positioning principle, and finally the final landing area of the table tennis ball is determined according to the principle of minority over majority; the present application can conveniently and quickly obtain the landing area of the table tennis ball on the table, so that the trainer can more intuitively understand his training process.

[0054] The round calculation method of the table tennis ball provided by the present application can detect the round state of the table tennis ball, count the number of rounds, and help the trainer to intuitively understand his training process and actual level, so as to positively promote the improvement of the table tennis technical level of the trainer.

[0055] It should be understood that the above general description and the following specific embodiments are only exemplary and explanatory, and cannot limit the scope of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0056] The following accompanying drawings are part of the specification of the present application, which show the embodiments of the present application, and together with the description of the specification, illustrate the principles of the present application.

[0057] Figure 1 A flow chart of a landing area detection method of a table tennis ball provided by an embodiment of the present application.

[0058] Figure 2 A division diagram of a table detection area in a landing area detection method of a table tennis ball provided by an embodiment of the present application.

[0059] Figure 3 A landing area schematic diagram in a landing area detection method of a table tennis ball provided by an embodiment of the present application. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clearly understood, the drawings and detailed description will be used to clearly explain the spirit of the present application. Any person skilled in the art can make changes and modifications to the technology taught by the present application without departing from the spirit and scope of the present application.

[0061] The illustrative embodiments of the present application and their description serve the purpose of explanations only and are not to be construed as limiting the present application. Furthermore, identical or similar elements / means are denoted by identical or similar reference numbers in the drawings and embodiments.

[0062] As to the "first", "second", "third", etc. used herein, they are not intended to refer to order or sequence, nor to limit the present application. They are merely used to distinguish the elements or operations described by the same technical terms.

[0063] As to the "comprise", "include", "have", "contain", etc. used herein, they are open terms, i.e. meaning comprising but not limited to.

[0064] As to the "and / or" used herein, it includes any or all combinations of the mentioned things.

[0065] As to the "plurality" herein, it includes "two" and "more than two"; as to the "multiple groups" herein, it includes "two groups" and "more than two groups".

[0066] Some words used to describe the present application will be discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art on the description related to the present application.

[0067] As shown in Figure 1 The method for detecting the landing area of a table tennis ball provided by the present application comprises the following steps:

[0068] S1, a left IMU (Inertial Measurement Unit) is arranged on the left half of the table tennis table, and a right IMU is arranged on the right half of the table tennis table.

[0069] S2, the left IMU and the right IMU are respectively subjected to data collection with a sampling period T1, three-dimensional acceleration and three-dimensional angular velocity at each sampling time are obtained and stored.

[0070] S3, N1 latest acceleration and angular velocity data are selected from the stored three-dimensional acceleration and three-dimensional angular velocity at each sampling time with a detection time window T3, and frequency domain analysis is performed to determine whether the N1 latest acceleration and angular velocity data are data of a collision between a table tennis ball and the table tennis table.

[0071] If the data represents a single collision between a ping-pong ball and the table, proceed to step S4; otherwise, return to step S2.

[0072] S4. Determine whether vibration sensors need to be placed on the left and right hemispheres of the table, depending on whether it is necessary to obtain the precise landing area of ​​the ping-pong ball on the table.

[0073] If it is not necessary to obtain the precise landing area of ​​the ping-pong ball on the table, but only to detect whether the ping-pong ball is on the table, then it is not necessary to place vibration sensors on the left and right hemispheres. The collision detection between the ping-pong ball and the left hemisphere can be completed by the left IMU or the collision detection between the ping-pong ball and the right hemisphere can be completed by the right IMU. That is, to detect whether the ping-pong ball is on the table, proceed to step S2.

[0074] If it is necessary to obtain the precise landing area of ​​the ping-pong ball on the table, then N (N≥3) vibration sensors need to be placed on the left and right hemispheres of the table, and then proceed to step S5.

[0075] S5. Data is collected from the vibration sensors on the left and right hemispheres at sampling periods T2 to obtain the high and low level signals at each sampling time.

[0076] When vibration is detected, the data exhibits a rising or falling edge variation characteristic.

[0077] The sampling period T2 is less than the sampling period T1.

[0078] S6. Obtain N2 (where N2 is greater than N1) level data points from all vibration sensors corresponding to the left or right hemisphere within the detection time window T3, and determine the initial edge time of each vibration sensor. Iterate through all non-collinear combinations of time differences among the N vibration sensors, and use the time difference positioning principle to determine the position coordinates of the collision point on the ping-pong table. The specific process is as follows:

[0079] S61. Let the coordinates of the three vibration sensors in one combination of time difference combinations on the table surface be (x, y, ...). s1 ,y s1 ), (x s2 ,y s2 ) and (x s3 ,y s3 The point of collision P between the ping-pong ball and the table. d The coordinates are (x d ,y d ),but

[0080] The distance r1 between the collision point and the first vibration sensor is:

[0081]

[0082] The distance r2 between the collision point and the second vibration sensor is:

[0083]

[0084] The distance r3 between the collision point and the third vibration sensor is:

[0085]

[0086] S62, calculate the difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the second vibration sensor 21 And the difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the third vibration sensor 31 ;

[0087] Wherein, the difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the second vibration sensor 21 Is:

[0088] r 21 = r2-r1 (4)

[0089] The difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the third vibration sensor 31 Is:

[0090] r 31 = r3-r1 (5)

[0091] Specifically, the distance difference r 21 And r 31 Can be obtained by the time difference of vibration transmission, the process is:

[0092] Assuming that the starting time of the first vibration sensor, the second vibration sensor and the third vibration sensor is t1, t2 and t3 respectively, then the time difference t d21 Of vibration transmission between the first vibration sensor and the second vibration sensor and the time difference t d31 Of vibration transmission between the first vibration sensor and the third vibration sensor are respectively:

[0093]

[0094] The propagation speed of vibration in the billiard table is V c obtained by calibration, so that the difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the second vibration sensor 21 And the difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the third vibration sensor 31 Are respectively:

[0095]

[0096] S63. According to equations (4) and (1), the difference r2 between the distance r2 between the collision point and the second vibration sensor and the distance r from the collision point to the first vibration sensor and the distance r from the collision point to the second vibration sensor can be obtained. 21 The relationship between the collision point and the distance r1 between the collision point and the first vibration sensor is as follows:

[0097]

[0098] According to equation (2), we can obtain

[0099]

[0100] According to equations (8) and (9), we can obtain

[0101]

[0102] Rearranging equation (10), we get

[0103]

[0104] In formula (11) K1 represents the modulus at the location of the first vibration sensor, and K2 represents the modulus at the location of the second vibration sensor. Then, equation (11) can be converted to:

[0105]

[0106] Let x in equation (12) d21 =x s2 -x s1 y d21 =y s2 -y s1 x d21 The y-axis represents the positional difference between the second vibration sensor and the first vibration sensor in the X-axis direction. d21 This represents the position difference between the second vibration sensor and the first vibration sensor in the Y-axis direction. By writing the left side of the equation in the form of a vector dot product, we can obtain the position variable. The equation is:

[0107]

[0108] S64. Similarly, based on the process in step S63, we can obtain...

[0109]

[0110] In equation (14), K3 represents the modulus at the location of the third vibration sensor. Let x in equation (14) d31 =xs3 -x s1 , y d31 = y s3 - y s1 , x d31 represents the position difference between the third vibration sensor and the first vibration sensor in the X-axis direction, y d31 represents the position difference between the third vibration sensor and the first vibration sensor in the Y-axis direction.

[0111] S65, according to formula (13) and formula (14) can be obtained

[0112]

[0113] Let Then the simplified formula of the position vector can be obtained from formula (15):

[0114]

[0115] In formula (16), the matrix M P1 , M P2 and M P3 are known or can be obtained by measurement.

[0116] wherein,

[0117] S66, according to formula (1) r1 2 is written in the form of vector inner product, and the following is obtained:

[0118]

[0119] S67, according to formula (16) and the coordinates of the first vibration sensor, the vector of the collision point pointing to the first vibration sensor is:

[0120]

[0121] In formula (18), P s1 represents the vector of the position coordinates of the first vibration sensor in the billiard table plane,

[0122]

[0123] S68, according to formula (17) and formula (18), the following is obtained:

[0124]

[0125] Let T P2 = M P1 M P2 , T P3 = M P1 · M P3, considering that T P2 T (T P3 -P s1 ) is a number, thus there is T P2 T (T P3 -P s1 ) = (T P3 -P s1 ) T T P2 .

[0126] Further rearranging formula (20) obtains:

[0127]

[0128] S69, after moving the terms of formula (21), a monomial quadratic equation group Ar1 2 +Br1+C=0 is obtained, wherein, B=2T P2 T (T P3 -P s1 ), C=(T P3 -P s1 ) 2 .

[0129] According to the monomial quadratic equation group Ar1 2 +Br1+C=0, it is obtained that

[0130] The value of r1 is brought into the expression , and the position coordinates of the collision point P d on the table tennis table are obtained.

[0131] S7, the position coordinates of the landing points of the M vibration sensor combinations in the set area are counted, and the final landing point area of the table tennis is determined according to the principle of minority over majority.

[0132] Wherein, the relationship between the number M of vibration sensor combinations and the number N of vibration sensors is:

[0133]

[0134] In formula (22), C represents the number of combinations.

[0135] Specifically, the set area is to divide the left half table and the right half table into any detection area according to requirements, such as Figure 2 The detection area can be a triangular area, a one-grid, a four-grid, a six-grid, a nine-grid or more.

[0136] For example, as Figure 3As shown, the table is divided into a left half table and a right half table, the left half table is evenly divided into a first area, a second area, a third area and a fourth area of the left half table according to a four-square grid, and the right half table is evenly divided into a first area, a second area, a third area and a fourth area of the right half table according to a four-square grid.

[0137] A table coordinate system OXYZ is established, and the coordinates of three groups of four vibration sensors are (0.1, 0.25), (-0.05, 0.35), (0.23, 0.15) and (0.15, 0.23) respectively.

[0138] Among them, (0.1, 0.25) belongs to the first area of the right half table, (-0.05, 0.35) belongs to the second area of the right half table, (0.23, 0.15) belongs to the first area of the right half table, and (0.15, 0.23) belongs to the first area of the right half table. According to the principle of minority obeying majority, the current landing area is the first area of the right half table.

[0139] The landing area detection method of the table tennis ball provided by the application can conveniently and quickly obtain the landing area of the table tennis ball on the table, so that the trainer can more intuitively understand his training process.

[0140] Based on the landing area detection method of the table tennis ball provided by the application, the application also provides a round calculation method of table tennis ball, which comprises the following steps:

[0141] Obtaining the landing point information sequence of the table tennis ball at each time;

[0142] Judging whether the landing points of adjacent times appear alternately in the areas on the left half table and the right half table, if yes, the round number is accumulated, otherwise, the round is ignored.

[0143] The round calculation method of the table tennis ball provided by the application uses the landing area detection result of the table tennis ball on the table, can detect the round state of the table tennis ball, and count the round number, so as to help the trainer intuitively understand his training process and actual level, and has a positive promoting effect on improving the table tennis technical level of the trainer.

[0144] Based on the landing area detection method of the table tennis ball provided by the application, the application also provides a table tennis table, which comprises a table body and an electric control assembly, wherein the table body comprises a left half table and a right half table, and the electric control assembly comprises a left IMU, a left vibration sensor, a right IMU, a right vibration sensor and an MCU.

[0145] The left IMU and the left vibration sensor are arranged on the left half table, and the right IMU and the right vibration sensor are arranged on the right half table. The left IMU and the right IMU are connected with the MCU, and the left vibration sensor and the right vibration sensor are connected with the MCU. The MCU can be arranged on the table body or outside the table body.

[0146] The MCU can be used to realize each step in the above-mentioned ball landing area detection method, and can also be used to realize each step in the above-mentioned game calculation method.

[0147] In the embodiment, the electric control assembly further comprises a left connector and a right connector. The left vibration sensor can be connected with the MCU through the left connector, and the right vibration sensor can be connected with the MCU through the right connector. The left connector can collect and send the signals of more than one left vibration sensor of the left half table to the MCU, and the right connector can collect and send the signals of more than one right vibration sensor of the right half table to the MCU. In addition, by arranging the left connector and the right connector, the left connector and the left vibration sensor can be easily disassembled or connected, and the right connector and the right vibration sensor can be easily disassembled or connected, so that the left half table and the right half table can be easily separated or connected.

[0148] In the embodiment, the table provided by the application further comprises a Bluetooth module, which is connected with the MCU. The MCU communicates with the application terminal or the Bluetooth remote controller through the Bluetooth module.

[0149] For example, the MCU can receive the control instruction sent by the application terminal or the Bluetooth remote controller through the Bluetooth module, and can also send the landing area detection result and the game data to the application terminal or the Bluetooth remote controller through the Bluetooth module.

[0150] In the embodiment, the table provided by the application further comprises a loudspeaker, which is connected with the MCU. The loudspeaker can realize the voice playing function, such as playing the landing detection result and the game data.

[0151] The table provided by the application further comprises a power interface, a power switch, a Bluetooth pairing button, a start / stop button, a state indicating lamp and other peripherals, so as to realize the manual control of the electric control equipment in the table.

[0152] In the embodiment, the height of the table body is adjustable. For example, the table legs in the table body can be arranged as upper table legs and lower table legs, and the upper table legs and the lower table legs are connected together by insertion. After adjusting to the required height, the upper table legs and the lower table legs are fixed by screws.

[0153] The embodiments of this application described above can be implemented in various hardware, software codes, or combinations thereof. For example, embodiments of this application may also represent program code executing the above methods in a data signal processor. This application may also relate to various functions performed by a computer processor, digital signal processor, microprocessor, or field-programmable gate array. The processor described above can be configured to perform specific tasks according to this application, which are accomplished by executing machine-readable software code or firmware code defining the specific methods disclosed in this application. The software code or firmware code can be developed to represent different programming languages ​​and different formats or forms. It can also represent software code compiled for different target platforms. However, the different code styles, types, and languages ​​of the software code performing tasks according to this application and other types of configuration code do not depart from the spirit and scope of this application.

[0154] The above description is merely an illustrative embodiment of this application. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of this application shall fall within the scope of protection of this application.

Claims

1. A method for detecting a landing area of a table tennis ball, characterized by, The method comprises the following steps: a left IMU is arranged on the left half table and a right IMU is arranged on the right half table; data of the left IMU and the right IMU are collected respectively at a sampling period T1, three-dimensional acceleration and three-dimensional angular velocity at each sampling time are obtained and stored; at each sampling time, N1 latest acceleration and angular velocity data are selected from the stored three-dimensional acceleration and three-dimensional angular velocity in a detection time window T3, and frequency domain analysis is performed to determine whether the N1 latest acceleration and angular velocity data are data of a collision between a table tennis ball and the table tennis table; if the data are data of a collision between a table tennis ball and the table tennis table, it is determined whether a vibration sensor needs to be arranged on the left half table and the right half table according to whether the landing area of the table tennis ball on the table tennis table needs to be obtained; if the landing area of the table tennis ball on the table tennis table needs to be obtained, N vibration sensors need to be arranged on the left half table and the right half table, wherein N≥3; data of the vibration sensors on the left half table and the right half table are collected respectively at a sampling period T2, high and low level signals at each sampling time are obtained; N2 level data of all vibration sensors corresponding to the left half table or the right half table in the detection time window T3 are obtained, and the starting time of each vibration sensor is determined; time difference combinations of all non-collinear three vibration sensors in the N vibration sensors are traversed, and the position coordinates of the collision point on the table tennis table are determined by using a time difference positioning principle; the landing position coordinates of M vibration sensor combinations in a set area are counted, and the final landing area of the table tennis ball is determined according to the principle of minority serving majority.

2. The method of claim 1, wherein if the N1 latest acceleration and angular velocity data are not data of a collision between a table tennis ball and the table tennis table, data of the left IMU and the right IMU are collected respectively at the sampling period T1 again, three-dimensional acceleration and three-dimensional angular velocity at each sampling time are obtained and stored.

3. The method of claim 1, wherein the ball landing area is determined by the following steps of: if the landing area of the table tennis ball on the table tennis table does not need to be obtained, collision detection of the table tennis ball and the left half table is completed by the left IMU or collision detection of the table tennis ball and the right half table is completed by the right IMU. ​ 4. The method for detecting the landing area of ​​a ping-pong ball according to claim 1, characterized in that, The process of determining the position coordinates of the collision point on the table tennis table by using the time difference positioning principle comprises the following steps: The position coordinates of three vibration sensors in a time difference combination are (x s1 ,y s1 ), (x s2 ,y s2 ) and (x s3 ,y s3 ) respectively, the position coordinates of the collision point P d of the table tennis ball and the table are (x d ,y d ), and the distance r1 between the collision point and the first vibration sensor is: a distance r2 between the collision point and the second vibration sensor is: a distance r3 between the collision point and the third vibration sensor is: the difference r between the distance of the collision point to the first vibration sensor and the distance of the collision point to the second vibration sensor 21 and the difference r between the distance of the collision point to the first vibration sensor and the distance of the collision point to the third vibration sensor 31 ; wherein r 21 = r2 - r1, r 31 = r3 - r1; According to the distance r1 between the collision point and the first vibration sensor and the difference r between the distance from the collision point to the first vibration sensor and the distance from the collision point to the second vibration sensor 21 The collision point position vector is calculated The relationship between the position coordinates (x s1 ,y s1 ), (x s2 ,y s2 ) and (x s3 ,y s3 ) of the three vibration sensors in the billiard table plane where x d21 represents a positional difference in the X-axis direction between the second vibration sensor and the first vibration sensor, x d21 = x s2 - x s1 ; y d21 represents a positional difference in the Y-axis direction between the second vibration sensor and the first vibration sensor, y d21 = y s2 - y s1 ; x d31 represents a positional difference in the X-axis direction between the third vibration sensor and the first vibration sensor, x d31 = x s3 - x s1 ; y d31 represents a positional difference in the Y-axis direction between the third vibration sensor and the first vibration sensor, y d31 = y s3 - y s1 ; K1 represents a modulus of the position of the first vibration sensor, K2 represents a modulus of the position of the second vibration sensor, K3 represents a modulus of the position of the third vibration sensor, Position vector of collision point The relationship between the position coordinates (x s1 ,y s1 ), (x s2 ,y s2 ) and (x s3 ,y s3 ) of the three vibration sensors on the billiard table plane is simplified to obtain a simplified expression of the position vector: In the formula, the matrix M P1 , M P2 , and M P3 are respectively a vector of the collision point pointing to the first vibration sensor is obtained according to a simplified expression of the position vector and the coordinates of the first vibration sensor: wherein P s1 a vector representing the position coordinates of the first vibration sensor in the table plane, an expression of the distance r1 between the collision point and the first vibration sensor is obtained: According to the vector pointing from the impact point to the first vibration sensor and r1 2 The expression is obtained: wherein B = 2T P2 T (T P3 -P s1 ), C = (T P3 -P s1 ) 2 ; T P2 = M P1 M P2 , T P3 = M P1 · M P3 ; Substitute the value of r1 into the expression to obtain the collision point P d Position coordinates on the table tennis table.

5. The method of claim 4, wherein the difference r between the distance of the impact point to the first vibration sensor and the distance of the impact point to the second vibration sensor 21 and the difference r between the distance of the impact point to the first vibration sensor and the distance of the impact point to the third vibration sensor 31 obtained by the time difference of the vibration transmission, wherein V c represents the propagation speed of vibration on the table, t d21 represents the time difference of vibration transmission of the first vibration sensor and the second vibration sensor, t d31 represents the time difference of vibration transmission of the first vibration sensor and the third vibration sensor, wherein t1, t2 and t3 respectively represent the starting time of the first vibration sensor, the second vibration sensor and the third vibration sensor.

6. The method of claim 1, wherein a relationship between the number M of the vibration sensor combinations and the number N of the vibration sensors is: wherein C represents the number of combinations.

7. A method of counting the rallies in a game of table tennis, characterized in that The method comprises the following steps: a landing point area detection method of a table tennis ball is adopted to obtain a landing point information sequence of the table tennis ball at each time; it is judged whether the landing points of adjacent times alternately appear in the areas on the left half table and the right half table, and if yes, the number of rounds is accumulated.

8. A table tennis table, characterized in that The billiard table comprises a table body and an electric control assembly, the table body comprises a left half table and a right half table, and the electric control assembly comprises a left IMU, a left vibration sensor, a right IMU, a right vibration sensor and an MCU; The left IMU and the left vibration sensor are arranged on the left half table, and the right IMU and the right vibration sensor are arranged on the right half table; the left IMU and the right IMU are connected with the MCU, and the left vibration sensor and the right vibration sensor are connected with the MCU; The MCU is used for realizing each step in the ball landing area detection method of the table tennis ball as claimed in any one of claims 1 to 6.

9. Table according to claim 8, characterized in that The MCU is also used for realizing each step in the round calculation method of the table tennis ball as claimed in claim 7.

10. The table as claimed in claim 8, characterized in that The table tennis table further comprises a Bluetooth module connected with the MCU, and the MCU communicates with an application terminal or a Bluetooth remote controller through the Bluetooth module.

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