High-precision wireless synchronous triggering acquisition system and method

Abstract

The invention discloses a high-precision wireless synchronous triggering acquisition system and method. The system comprises a data acquisition terminal and a plurality of sensor acquisition terminals, the data acquisition terminal is used for broadcasting a time synchronization signal to the plurality of sensor acquisition terminals, receiving sensor data returned by the plurality of sensor acquisition terminals, and forwarding the received synchronous sampling data to the upper computer; the sensor acquisition terminal is used for performing time synchronization by using the time synchronization signal broadcasted by the data acquisition terminal, generating a synchronization trigger signal, sending the synchronization trigger signal to the sensor, controlling the sensor to perform data acquisition, reconstructing the sensor data according to the data acquired by the sensor and the time synchronization signal, and sending the reconstructed data to the data acquisition terminal. And synchronously sampled sensor data is generated and sent to a data acquisition terminal. According to the invention, high-precision wireless synchronous data acquisition of a plurality of sensor circuit boards can be realized at positions without global navigation satellite system (GNSS) satellite signals.

Description

Technical Field

[0001] The present invention relates to the field of sensor data acquisition, and in particular to a high-precision wireless synchronous trigger acquisition system and method. Background Art

[0002] In scenarios where multi-sensor data fusion is required, multi-sensor data synchronous acquisition technology is often needed. For example, in the field of power measurement, it is usually necessary to collect voltage and current data at the same time. If there is a phase error in the acquisition of voltage and current, it will cause errors in power calculation; in the field of acoustic measurement, such as an acoustic measurement system using a microphone matrix, it is necessary to measure and analyze the spectrum, phase and other information of multiple microphone signals, so synchronous acquisition is required; in the field of intelligent driving, it is necessary to use millimeter-wave radar, lidar, IMU, and camera data for fusion; in the field of engineering applications, large-scale structure detection, such as strain detection, shake detection, etc.

[0003] It is relatively easy to synchronize the data of multiple sensors on the same circuit board. You only need to use the same clock source to synchronize the data of multiple sensors. However, if multiple sensors need to be distributed on different circuit boards, each sensor has its own clock source. In order to effectively integrate the perception data of multiple sensors, time synchronization must be performed. If phase information needs to be analyzed, the accuracy of synchronization will be very high, otherwise phase jitter will occur and phase noise will be introduced.

[0004] The existing technology for time synchronization generally adopts the network timing protocol NTP or PTP protocol to complete time synchronization. Both protocols use the server to synchronize time with the client. The accuracy of timing is closely related to the stability of the network. If used in a wireless synchronous acquisition system, the timing accuracy error will reach several milliseconds or even tens of milliseconds. This timing accuracy cannot be used in a wireless synchronous acquisition system.

[0005] The only solution that can achieve high-precision wireless synchronization with existing technologies is the Global Navigation Satellite System (GNSS). The world's four major satellite navigation system suppliers include China's Beidou Satellite Navigation System (BDS), the United States' Global Positioning System (GPS), Russia's GLONASS Satellite Navigation System (GLONASS) and the European Union's Galileo Satellite Navigation System (GALILEO). Navigation satellites in GNSS have built-in high-precision atomic clocks, and GNSS receivers can obtain ultra-high-precision clock signals by solving navigation satellite signals. The circuit boards of multiple sensors use GNSS time as a unified time source, and GNSS provides reference time to each sensor. Each sensor calibrates its own clock time based on the provided reference time. This time synchronization solution can achieve microsecond or even sub-microsecond clock synchronization, but it can only be used in open outdoor venues. It must be used in locations where the Global Navigation Satellite System (GNSS) satellite signal can be received normally. It cannot be used in application scenarios such as indoors, tunnels, and underground.

[0006] In application scenarios such as indoors, in tunnels, and underground, current technical solutions mostly use cables to transmit synchronous control signals. It is difficult to transmit synchronous control signals over long distances using cables, and in some scenarios, it is impossible to use cables to transmit synchronous control signals. Summary of the invention

[0007] In view of the technical defects and technical drawbacks in the prior art, the embodiments of the present invention provide a high-precision wireless synchronous trigger acquisition system and method that overcomes the above problems or at least partially solves the above problems. The specific scheme is as follows:

[0008] As a first aspect of the present invention, a high-precision wireless synchronous trigger acquisition system is provided, the system comprising a data acquisition terminal and a plurality of sensor acquisition terminals;

[0009] The data acquisition terminal is used to broadcast a time synchronization signal to the multiple sensor acquisition terminals, receive sensor data returned by the multiple sensor acquisition terminals, and forward the received synchronous sampling data to the host computer;

[0010] The sensor acquisition terminal is used to perform time synchronization using the time synchronization signal broadcast by the data acquisition terminal, and generate a synchronization trigger signal, which is sent to the sensor to control the sensor to perform data acquisition, reconstruct the sensor data based on the data collected by the sensor and the time synchronization signal, generate synchronously sampled sensor data and send it to the data acquisition terminal.

[0011] Furthermore, the sensor acquisition terminal is connected to the data acquisition terminal via a wireless transceiver, and the data acquisition terminal is connected to the host computer via a network cable.

[0012] Furthermore, the data acquisition terminal includes:

[0013] The first wireless transceiver is used for receiving and transmitting time synchronization signals;

[0014] The first MCU processing unit: used for parameter calculation, various timer control, transmission data processing, generation of synchronous trigger signal, sensor data collection, sensor data reporting, and communication with the host computer;

[0015] Network interface: used to communicate with the host computer to complete data transmission and parameter configuration;

[0016] The first synchronous trigger signal port is used to output a synchronous trigger signal to the sensor to control the sensor to collect data;

[0017] The first sensor interface is used to read data collected by the sensor.

[0018] Furthermore, all calculations and control processes of the data acquisition terminal are completed in the first MCU processing unit, and the specific implementation process of the data acquisition terminal includes:

[0019] Step 101, parameter initialization, configuration of the maximum coverage distance of the data acquisition terminal and the output period T of the synchronization trigger signal TRIG;

[0020] Step 102, the first MCU processing unit calculates the delay from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance of the data acquisition terminal;

[0021] Step 103, the first MCU processing unit starts a first cycle timer according to the output cycle T of the synchronization trigger signal TRIG;

[0022] Step 104, the first MCU processing unit starts the first delay timer in the first periodic timer interrupt according to the delay of the synchronization trigger signal TRIG output in step 102, and controls the wireless transceiver to transmit the time synchronization signal;

[0023] Step 105, the first MCU processing unit generates a synchronization trigger signal TRIG in the first delay timer interrupt to control the sensor to collect data;

[0024] Step 106, the first MCU processing unit waits in the main thread for the sensor to collect data. When the sensor collects data, the sensor collects data and reports the sensor collects data. The main thread executes step 106 in a loop.

[0025] The data acquisition terminal periodically generates a synchronous trigger signal TRIG through the cooperation of a first periodic timer and a first delay timer to trigger the sensor to collect data.

[0026] Furthermore, the sensor acquisition terminal includes:

[0027] The second wireless transceiver is used for receiving and transmitting time synchronization signals;

[0028] The second MCU processing unit is used for parameter calculation, various timer control, receiving and transmitting data processing, clock calibration control, generating synchronization trigger signals, collecting sensor data and reporting sensor data;

[0029] DAC digital-to-analog converter, used to convert digital signals into analog signals, and control the output frequency of the voltage-controlled crystal oscillator by controlling the size of the analog signal;

[0030] Voltage-controlled crystal oscillator: used to output clock to the MCU processing unit, so that the MCU processing unit uses the clock to control various timers to generate corresponding interrupts, thereby achieving the effect of controlling the timing;

[0031] The second synchronous trigger signal port: used to output a synchronous trigger signal to the sensor to control the sensor to collect data;

[0032] Second sensor interface: used to read the data collected by the sensor.

[0033] Furthermore, all calculations and control processes of the sensor acquisition terminal are completed in the second MCU processing unit, and the specific implementation process of the sensor acquisition terminal includes:

[0034] Step 201, parameter initialization, configuration of the maximum coverage distance D of the sensor acquisition terminal, the distance d from the sensor acquisition terminal to the data acquisition terminal, and the output period T of the synchronization trigger signal TRIG;

[0035] Step 202, the second MCU processing unit calculates the delay t4 from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance D of the sensor acquisition terminal;

[0036] Step 203, the second MCU processing unit calculates the delay parameter t5 according to the distance d from the sensor acquisition terminal to the data acquisition terminal;

[0037] Step 204, the second MCU processing unit calculates the delay parameter t3 according to the output period T of the synchronization trigger signal TRIG;

[0038] Step 205, the second MCU processing unit waits to receive the time synchronization signal of the data acquisition terminal, and when the second wireless transceiver receives the time synchronization signal of the data acquisition terminal, a receiving interrupt is generated, and the second MCU processing unit responds to the receiving interrupt;

[0039] Step 206, the second MCU processing unit calculates the difference between the output frequency of the voltage-controlled crystal oscillator and the frequency of the crystal oscillator of the data acquisition terminal according to the output period T of the synchronization trigger signal TRIG and the local clock count value in the receiving interrupt, and based on the difference, adjusts the output voltage of the DAC digital-to-analog converter so that the output frequency of the voltage-controlled crystal oscillator is the same as the frequency of the crystal oscillator of the data acquisition terminal, and starts the second delay timer according to the parameter t5, and starts the third delay timer according to the parameter t3;

[0040] Step 207, the second MCU processing unit generates a synchronization trigger signal TRIG in the second delay timer interrupt to control the sensor to collect data;

[0041] Step 208: The second MCU processing unit controls the second wireless transceiver to transmit a time synchronization signal for relaying in the third delay timer interrupt.

[0042] Further,

[0043] t3 is the time from when the sensor acquisition terminal receives the synchronization signal interrupt from the data acquisition terminal to when it transmits the synchronization signal relay, t3 = T – t2, where t2 is measured in the laboratory environment and is a fixed value that does not change with environmental changes;

[0044] t4 is the delay from the sensor acquisition terminal transmitting the synchronization signal to the output of the synchronization trigger signal TRIG, t4 = D / c, c represents the speed of light;

[0045] t5 is the delay from the sensor acquisition terminal receiving the synchronization signal to outputting the synchronization trigger signal TRIG, t5 = t4 - t1 - t2 = (Dd) / c - t2, where t1 is the wireless transmission delay from the data acquisition terminal to the sensor acquisition terminal, t1 = d / c.

[0046] As a second aspect of the present invention, a high-precision wireless synchronous trigger acquisition method is provided, the method comprising:

[0047] Broadcasting a time synchronization signal to a sensor acquisition terminal through a data acquisition terminal, receiving sensor data returned by a plurality of the sensor acquisition terminals, and forwarding the received sensor data to a host computer;

[0048] The sensor acquisition terminal is used to perform time synchronization using the time synchronization signal broadcast by the data acquisition terminal, and generate a synchronization trigger signal, which is sent to the sensor to control the sensor to perform data acquisition, reconstruct the sensor data based on the data collected by the sensor and the time synchronization signal, generate synchronously sampled sensor data and send it to the data acquisition terminal.

[0049] Furthermore, all calculations and control processes of the data acquisition terminal are completed in the first MCU processing unit, and the specific implementation process of the data acquisition terminal includes:

[0050] Step 101, parameter initialization, configuration of the maximum coverage distance of the data acquisition terminal and the output period T of the synchronization trigger signal TRIG;

[0051] Step 102, the first MCU processing unit calculates the delay from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance of the data acquisition terminal;

[0052] Step 103, the first MCU processing unit starts the first cycle timer 1 according to the output cycle T of the synchronization trigger signal TRIG;

[0053] Step 104, the first MCU processing unit starts the first delay timer in the first periodic timer interrupt according to the delay of the synchronization trigger signal TRIG output in step 102, and controls the wireless transceiver to transmit the time synchronization signal;

[0054] Step 105, the first MCU processing unit generates a synchronization trigger signal TRIG in the first delay timer interrupt to control the sensor to collect data;

[0055] Step 106, the first MCU processing unit waits in the main thread for the sensor to collect data. When the sensor collects data, the sensor collects data and reports the sensor collects data. The main thread executes step 106 in a loop.

[0056] The data acquisition terminal periodically generates a synchronous trigger signal TRIG through the cooperation of a first periodic timer and a first delay timer to trigger the sensor to collect data.

[0057] Furthermore, all calculations and control processes of the sensor acquisition terminal are completed in the second MCU processing unit, and the specific implementation process of the sensor acquisition terminal includes:

[0058] Step 201, parameter initialization, configuration of the maximum coverage distance D of the sensor acquisition terminal, the distance d from the sensor acquisition terminal to the data acquisition terminal, and the output period T of the synchronization trigger signal TRIG;

[0059] Step 202, the second MCU processing unit calculates the delay t4 from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance D of the sensor acquisition terminal;

[0060] Step 203, the second MCU processing unit calculates the delay parameter t5 according to the distance d from the sensor acquisition terminal to the data acquisition terminal;

[0061] Step 204, the second MCU processing unit calculates the delay parameter t3 according to the output period T of the synchronization trigger signal TRIG;

[0062] Step 205, the second MCU processing unit waits to receive the time synchronization signal of the data acquisition terminal, and when the second wireless transceiver receives the time synchronization signal of the data acquisition terminal, a receiving interrupt is generated, and the second MCU processing unit responds to the receiving interrupt;

[0063] Step 206, the second MCU processing unit calculates the difference between the output frequency of the voltage-controlled crystal oscillator and the frequency of the crystal oscillator of the data acquisition terminal according to the output period T of the synchronization trigger signal TRIG and the local clock count value in the receiving interrupt, and based on the difference, adjusts the output voltage of the DAC digital-to-analog converter so that the output frequency of the voltage-controlled crystal oscillator is the same as the frequency of the crystal oscillator of the data acquisition terminal, and starts the second delay timer according to the parameter t5, and starts the third delay timer according to the parameter t3;

[0064] Step 207, the second MCU processing unit generates a synchronization trigger signal TRIG in the second delay timer interrupt to control the sensor to collect data;

[0065] Step 208: The second MCU processing unit controls the second wireless transceiver to transmit a time synchronization signal for relaying in the third delay timer interrupt.

[0066] The present invention has the following beneficial effects:

[0067] The present invention can realize high-precision wireless synchronous data collection by multiple sensor circuit boards in locations where there are no global satellite navigation system (GNSS) satellite signals. Time synchronization using the technical solution of the present invention can achieve microsecond or even sub-microsecond synchronization, which can fully meet the needs of application scenarios such as phase analysis or 3D reconstruction of multiple sensors collecting data. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 A schematic diagram of the structure of a high-precision wireless synchronous trigger acquisition system provided by an embodiment of the present invention;

[0069] Figure 2 A block diagram of a data acquisition terminal system provided by an embodiment of the present invention;

[0070] Figure 3 A block diagram of a sensor acquisition terminal system provided by an embodiment of the present invention;

[0071] Figure 4 A timing diagram of a typical application scenario provided by an embodiment of the present invention;

[0072] Figure 5 It is a flow chart of the data acquisition terminal in the present invention;

[0073] Figure 6 A flow chart of a sensor acquisition terminal provided by an embodiment of the present invention;

[0074] Figure 7 A schematic diagram of a typical application scenario provided by an embodiment of the present invention;

[0075] Figure 8 A schematic diagram of a wireless synchronization trigger network topology corresponding to a typical application scenario 1 provided in an embodiment of the present invention;

[0076] In the figure: 101, sensor, 102, sensor acquisition terminal, 103, data acquisition terminal, 104, host computer, 201, second wireless transceiver, 202, second MCU processing unit, 203, DAC digital-to-analog converter, 204, second synchronization trigger signal port, 205, second sensor interface, 301, first wireless transceiver, 302, first MCU processing unit, 303, network interface, 304, first synchronization trigger signal port, 305, first sensor interface. DETAILED DESCRIPTION

[0077] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0078] Figure 1 The schematic diagram of the structure of the high-precision wireless synchronous trigger acquisition system provided by the embodiment of the present invention is shown in FIG. Figure 1 As shown, a high-precision wireless synchronous trigger acquisition system provided by an embodiment of the present invention mainly includes a data acquisition terminal 103 and multiple sensor acquisition terminals 102;

[0079] The data acquisition terminal 103 is used to broadcast a time synchronization signal to the multiple sensor acquisition terminals 102, receive sensor data returned by the multiple sensor acquisition terminals 102, and forward the received synchronous sampling data to the host computer 104;

[0080] The sensor acquisition terminal 102 is used to perform time synchronization using the time synchronization signal broadcast by the data acquisition terminal 103, and generate a synchronization trigger signal, and send the synchronization trigger signal to the sensor 101 to control the sensor 101 to perform data acquisition, reconstruct the sensor data according to the data collected by the sensor 101 and the time synchronization signal, generate synchronously sampled sensor data and send it to the data acquisition terminal 103.

[0081] The sensor acquisition terminal 102 is connected to the data acquisition terminal 103 via a wireless transceiver, and the data acquisition terminal 103 is connected to the host computer 104 via a network cable.

[0082] The present invention provides a high-precision wireless synchronous trigger acquisition system, which can realize a technical solution for high-precision wireless synchronous trigger data acquisition in an environment without satellite signals, such as tunnels, underground pipelines, wind turbine towers, etc.; in addition, the present invention also supports relay mode expansion. Since the time synchronization signal transmission is unidirectional, it can support infinite cascading and can cover tens of kilometers or even hundreds of kilometers. The accuracy of the synchronous trigger can reach microseconds.

[0083] Figure 2 For a system block diagram of the data acquisition terminal 103 provided in an embodiment of the present invention, see Figure 2 As shown, the data acquisition terminal 103 mainly includes:

[0084] The first wireless transceiver 301 is used for receiving and transmitting time synchronization signals;

[0085] The first MCU processing unit 302 is used for parameter calculation, various timer control, transmission data processing, generating synchronization trigger signals, collecting sensor data, reporting sensor data, and communicating with the host computer 104;

[0086] Network interface 303: used to communicate with the host computer 104 to complete data transmission and parameter configuration;

[0087] The first synchronous trigger signal port 304 is used to output a synchronous trigger signal to the sensor 101 to control the sensor 101 to collect data;

[0088] The first sensor interface 305 is used to read the data collected by the sensor 101 .

[0089] Figure 3 For a system block diagram of the sensor acquisition terminal 102 provided in an embodiment of the present invention, see Figure 3 As shown, the sensor acquisition terminal 102 mainly includes:

[0090] The second wireless transceiver 201 is used for receiving and transmitting time synchronization signals;

[0091] The second MCU processing unit 202 is used for parameter calculation, various timer control, receiving and transmitting data processing, clock calibration control, generating synchronization trigger signals, collecting sensor data and reporting sensor data;

[0092] DAC digital-to-analog converter 203, used to convert digital signals into analog signals, and control the output frequency of the voltage-controlled crystal oscillator by controlling the magnitude of the analog signals;

[0093] Voltage-controlled crystal oscillator: used to output clock to the MCU processing unit, so that the MCU processing unit uses the clock to control various timers to generate corresponding interrupts, thereby achieving the effect of controlling the timing;

[0094] The second synchronous trigger signal port 204 is used to output a synchronous trigger signal to the sensor 101 to control the sensor 101 to collect data;

[0095] The second sensor interface 205 is used to read the data collected by the sensor 101 .

[0096] There are two second wireless transceivers 201 , one of which is used to receive data from the data collection terminal 103 , and the other is used to transmit data to the data collection terminal 103 .

[0097] In the high-precision synchronous trigger acquisition system described in the present invention, there is one data acquisition terminal 103, which serves as the master device of the time synchronization signal and broadcasts the time synchronization signal. The sensor acquisition terminal 102 can have multiple devices, which serve as relay devices or slave devices of the time synchronization signal and receive the time synchronization signal. As a relay device, it needs to forward the time synchronization signal to achieve the relay effect. Figure 4 The timing relationship diagram of the work between various devices in the typical application of the present invention is shown in FIG. The synchronous trigger signal of the sensor acquisition terminal 102 and the synchronous trigger signal of the data acquisition terminal 103 are uniformly defined as TRIG signals. The technical effect to be achieved by the present invention is that the time deviation of the TRIG signals output by all devices in the system is in the microsecond level. Figure 4 The specific descriptions of the time parameters are as follows:

[0098] T is the output period of the TRIG signal, which is an input parameter that can be configured by the system.

[0099] t1 is the wireless transmission delay from the data acquisition terminal 103 to the sensor acquisition terminal 102 (relay node), which is calculated by the distance d1 from the data acquisition terminal 103 to the sensor acquisition terminal 102 (relay node). d1 is an input parameter of the sensor acquisition terminal 102 (relay node) and is measured by a professional distance measuring instrument during on-site installation. The specific calculation formula is: t1=d1 / c, where c represents the speed of light.

[0100] t2 is the sending and receiving processing delay of the wireless transceiver. t2 can be measured in a laboratory environment. It is a fixed value and will not change with environmental changes.

[0101] t3 is the time from when the sensor acquisition terminal 102 (relay node) receives the synchronization signal interrupt from the data acquisition terminal 103 to when it transmits the synchronization signal relay. The calculation formula is t3 = T – t2. The wireless transmission delay t1 from the data acquisition terminal 103 to the sensor acquisition terminal 102 (relay node) does not need to be considered here. Therefore, the transmission time of the synchronization signal relay will be delayed by t1 compared to the transmission time of the synchronization signal of the data acquisition terminal 103. Figure 4 shown.

[0102] t4 is the delay from the data acquisition terminal 103 transmitting the synchronization signal to the output of the synchronization trigger signal TRIG, which is calculated based on the system parameter maximum coverage distance D. The specific calculation formula is: t4=D / c, where c represents the speed of light.

[0103] t5 is the delay from the sensor acquisition terminal 102 (relay node) receiving the synchronization signal to the output of the synchronization trigger signal TRIG, which is calculated based on the system parameter maximum coverage distance D and the distance d1 from the data acquisition terminal 103 to the sensor acquisition terminal 102 (relay node). The specific calculation formula is: t5 = t4 - t1 - t2 = (D - d1) / c - t2, where c represents the speed of light.

[0104] t6 is the wireless transmission delay from the data acquisition terminal 103 to the sensor acquisition terminal 102, which is calculated based on the distance d2 from the data acquisition terminal 103 to the sensor acquisition terminal 102. d2, as an input parameter of the sensor acquisition terminal 102, is measured by a professional distance measuring instrument during on-site installation. The specific calculation formula is: t6 = d2 / c, where c represents the speed of light.

[0105] t7 is the delay from the sensor acquisition terminal 102 receiving the synchronization signal to outputting the synchronization trigger signal TRIG, which is calculated based on the system parameter maximum coverage distance D and the distance d2 from the data acquisition terminal 103 to the sensor acquisition terminal 102. The specific calculation formula is: t7 = t4-t6-t2 = (D-d2) / c-t2, where c represents the speed of light.

[0106] The main usage of the present invention is to measure the distance between the data acquisition terminal 103 and each sensor acquisition terminal 102 (including relay nodes) through a professional distance measuring instrument during on-site installation, and then set the system parameters, namely the maximum coverage distance D and the output period T of the TRIG signal. The data acquisition terminal 103 and each sensor acquisition terminal 102 can calculate the relative delay of their respective TRIG signal outputs, and finally achieve the effect that the time deviation of all TRIG signal outputs of the entire system is in the microsecond level.

[0107] In some embodiments, all calculations and control processes of the data acquisition terminal 103 are completed in the first MCU processing unit 302, see Figure 5 As shown, the specific implementation process of the data acquisition terminal 103 includes:

[0108] Step 101, parameter initialization, configuring the maximum coverage distance of the data acquisition terminal 103 and the output period T of the synchronous trigger signal TRIG;

[0109] Step 102, the first MCU processing unit 302 calculates the delay from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance of the data acquisition terminal 103;

[0110] Step 103, the first MCU processing unit 302 starts a first cycle timer according to the output cycle T of the synchronization trigger signal TRIG;

[0111] Step 104, the first MCU processing unit 302 starts the first delay timer in the first periodic timer interrupt according to the delay of the synchronization trigger signal TRIG output in step 102, and controls the wireless transceiver to transmit the time synchronization signal;

[0112] Step 105, the first MCU processing unit 302 generates a synchronization trigger signal TRIG in the first delay timer interrupt to control the sensor 101 to collect data;

[0113] Step 106, the first MCU processing unit 302 waits in the main thread for the sensor 101 to collect data. When the sensor 101 collects data, the first MCU processing unit 302 reads the data collected by the sensor 101 and reports the data collected by the sensor 101. The main thread executes step 106 in a loop.

[0114] The data collection terminal 103 cooperates with the first periodic timer and the first delay timer to periodically generate a synchronous trigger signal TRIG to trigger the sensor 101 to collect data.

[0115] In some embodiments, all calculations and control processes of the sensor acquisition terminal 102 are completed in the second MCU processing unit 202, see Figure 6 As shown, the specific implementation process of the sensor acquisition terminal 102 includes:

[0116] Step 201, parameter initialization, configuring the maximum coverage distance D of the sensor acquisition terminal 102, the distance d from the sensor acquisition terminal 102 to the data acquisition terminal 103, and the output period T of the synchronization trigger signal TRIG;

[0117] Step 202, the second MCU processing unit 202 calculates the delay t4 from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance D of the sensor acquisition terminal 102;

[0118] Step 203, the second MCU processing unit 202 calculates the delay parameter t5 according to the distance d from the sensor acquisition terminal 102 to the data acquisition terminal 103;

[0119] Step 204, the second MCU processing unit 202 calculates the delay parameter t3 according to the output period T of the synchronization trigger signal TRIG;

[0120] Step 205, the second MCU processing unit 202 waits to receive the time synchronization signal of the data acquisition terminal 103, when the second wireless transceiver 201 for receiving signals receives the time synchronization signal of the data acquisition terminal 103, a receiving interrupt is generated, and the second MCU processing unit 202 responds to the receiving interrupt;

[0121] Step 206, the second MCU processing unit 202 calculates the difference between the output frequency of the voltage-controlled crystal oscillator and the frequency of the crystal oscillator of the data acquisition terminal 103 according to the output period T of the synchronization trigger signal TRIG and the local clock count value in the receiving interrupt, and based on the difference, adjusts the output voltage of the DAC digital-to-analog converter 203 so that the output frequency of the voltage-controlled crystal oscillator is the same as the frequency of the crystal oscillator of the data acquisition terminal 103, and starts the second delay timer according to the parameter t5, and starts the third delay timer according to the parameter t3;

[0122] Step 207, the second MCU processing unit 202 generates a synchronization trigger signal TRIG in the second delay timer interrupt to control the sensor 101 to collect data;

[0123] Step 208: the second MCU processing unit 202 controls the second wireless transceiver 201 for transmitting signals to transmit a time synchronization signal for relaying in the third delay timer interruption.

[0124] Figure 7 A schematic diagram of a typical application scenario provided by an embodiment of the present invention, see Figure 7As shown, multiple sensors 101 are installed on a wind turbine for synchronous data collection to analyze the posture and deformation of the wind turbine during operation. Therefore, high-precision synchronous data collection is required. The higher the synchronization accuracy, the more accurate the detection result. However, due to the particularity of the wind turbine structure, its tower part is composed of multiple relatively closed spaces. The blades and the tower are in continuous relative motion during operation, and cables cannot be arranged inside the blades, so that each sensor 101 cannot achieve high-precision synchronous data collection. In view of this situation, the technical solution of the present invention is applied. A data acquisition terminal 103 in the present invention is installed at the bottom layer of the wind turbine, connected to the background server through a dedicated network, and a sensor acquisition terminal 102 in the present invention is installed on the other layers of the wind turbine tower and the blades. All terminals in the present invention can provide synchronous trigger signals with a time deviation of microseconds. The synchronous trigger signal controls all sensors 101 to collect data at the same time, thereby ensuring the accuracy of the detection results.

[0125] Figure 8 A schematic diagram of a wireless synchronization trigger network topology corresponding to a typical application scenario provided by an embodiment of the present invention, see Figure 8 As shown, it can be seen that the technical solution of the present invention supports chain, star and hybrid networking modes, is convenient and flexible, has good scalability, and can adapt to complex geographical environments and application scenarios, such as complex underground structures, tunnels, mines, etc.

[0126] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-precision wireless synchronous trigger acquisition system, characterized in that: The system includes a data acquisition terminal and a plurality of sensor acquisition terminals; The data acquisition terminal is used to broadcast a time synchronization signal to the multiple sensor acquisition terminals, receive sensor data returned by the multiple sensor acquisition terminals, and forward the received synchronous sampling data to the host computer; The sensor acquisition terminal is used to perform time synchronization using the time synchronization signal broadcast by the data acquisition terminal, and generate a synchronization trigger signal, which is sent to the sensor to control the sensor to perform data acquisition, reconstruct the sensor data based on the data collected by the sensor and the time synchronization signal, generate synchronously sampled sensor data and send it to the data acquisition terminal.

2. The high-precision wireless synchronous trigger acquisition system according to claim 1, characterized in that: The sensor acquisition terminal is connected to the data acquisition terminal via a wireless transceiver, and the data acquisition terminal is connected to the host computer via a network cable.

3. The high-precision wireless synchronous trigger acquisition system according to claim 1, characterized in that: The data acquisition terminal comprises: The first wireless transceiver is used for receiving and transmitting time synchronization signals; The first MCU processing unit: used for parameter calculation, various timer control, transmission data processing, generation of synchronous trigger signal, sensor data collection, sensor data reporting, and communication with the host computer; Network interface: used to communicate with the host computer to complete data transmission and parameter configuration; The first synchronous trigger signal port is used to output a synchronous trigger signal to the sensor to control the sensor to collect data; The first sensor interface is used to read data collected by the sensor.

4. The high-precision wireless synchronous trigger acquisition system according to claim 3, characterized in that: All calculations and control processes of the data acquisition terminal are completed in the first MCU processing unit. The specific implementation process of the data acquisition terminal includes: Step 101, parameter initialization, configuration of the maximum coverage distance of the data acquisition terminal and the output period T of the synchronization trigger signal TRIG; Step 102, calculating the delay from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance of the data acquisition terminal; Step 103, starting a first cycle timer according to the output cycle T of the synchronization trigger signal TRIG; Step 104, in the first periodic timer interruption, according to the delay of outputting the synchronization trigger signal TRIG in step 102, starting the first delay timer, and controlling the wireless transceiver to transmit the time synchronization signal; Step 105, generating a synchronous trigger signal TRIG in the first delay timer interrupt to control the sensor to collect data; Step 106, waiting for the sensor to collect data in the main thread, when the sensor collects data, reading the sensor collected data and reporting the sensor collected data, the main thread loops to execute step 106; The data acquisition terminal periodically generates a synchronous trigger signal TRIG through the cooperation of a first periodic timer and a first delay timer to trigger the sensor to collect data.

5. The high-precision wireless synchronous trigger acquisition system according to claim 1, characterized in that: The sensor acquisition terminal includes: The second wireless transceiver is used for receiving and transmitting time synchronization signals; The second MCU processing unit is used for parameter calculation, various timer control, receiving and transmitting data processing, clock calibration control, generating synchronization trigger signals, collecting sensor data and reporting sensor data; DAC digital-to-analog converter, used to convert digital signals into analog signals, and control the output frequency of the voltage-controlled crystal oscillator by controlling the size of the analog signal; Voltage-controlled crystal oscillator: used to output clock to the MCU processing unit, so that the MCU processing unit uses the clock to control various timers to generate corresponding interrupts, thereby achieving the effect of controlling the timing; The second synchronous trigger signal port: used to output a synchronous trigger signal to the sensor to control the sensor to collect data; Second sensor interface: used to read the data collected by the sensor.

6. The high-precision wireless synchronous trigger acquisition system according to claim 5, characterized in that: All calculations and control processes of the sensor acquisition terminal are completed in the second MCU processing unit. The specific implementation process of the sensor acquisition terminal includes: Step 201, parameter initialization, configuration of the maximum coverage distance D of the sensor acquisition terminal, the distance d from the sensor acquisition terminal to the data acquisition terminal, and the output period T of the synchronization trigger signal TRIG; Step 202, calculating the delay t4 from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance D of the sensor acquisition terminal; Step 203, calculating the delay parameter t5 according to the distance d from the sensor acquisition terminal to the data acquisition terminal; Step 204, calculating the delay parameter t3 according to the output period T of the synchronization trigger signal TRIG; Step 205, waiting to receive the time synchronization signal of the data acquisition terminal, when the second wireless transceiver receives the time synchronization signal of the data acquisition terminal, a receiving interrupt is generated, and the second MCU processing unit responds to the receiving interrupt; Step 206, in the receiving interrupt, according to the output period T of the synchronization trigger signal TRIG and the local clock count value, calculate the difference between the output frequency of the voltage-controlled crystal oscillator and the frequency of the crystal oscillator of the data acquisition terminal, based on the difference, adjust the output voltage of the DAC digital-to-analog converter so that the output frequency of the voltage-controlled crystal oscillator is the same as the frequency of the crystal oscillator of the data acquisition terminal, and at the same time start the second delay timer according to the parameter t5, and start the third delay timer according to the parameter t3; Step 207, generating a synchronous trigger signal TRIG in the second delay timer interrupt to control the sensor to collect data; Step 208: Control the second wireless transceiver to transmit a time synchronization signal for relaying in the third delay timer interrupt.

7. The high-precision wireless synchronous trigger acquisition system according to claim 6, characterized in that: t3 is the time from when the sensor acquisition terminal receives the synchronization signal interrupt from the data acquisition terminal to when it transmits the synchronization signal relay, t3 = T – t2, where t2 is measured in the laboratory environment and is a fixed value that does not change with environmental changes; t4 is the delay from the sensor acquisition terminal transmitting the synchronization signal to the output of the synchronization trigger signal TRIG, t4 = D / c, c represents the speed of light; t5 is the delay from the sensor acquisition terminal receiving the synchronization signal to outputting the synchronization trigger signal TRIG, t5 = t4 - t1 - t2 = (Dd) / c - t2, where t1 is the wireless transmission delay from the data acquisition terminal to the sensor acquisition terminal, t1 = d / c.

8. A high-precision wireless synchronous trigger acquisition method, characterized in that: The method comprises: Broadcasting a time synchronization signal to a sensor acquisition terminal through a data acquisition terminal, receiving sensor data returned by a plurality of the sensor acquisition terminals, and forwarding the received sensor data to a host computer; The sensor acquisition terminal is used to perform time synchronization using the time synchronization signal broadcast by the data acquisition terminal, and generate a synchronization trigger signal, which is sent to the sensor to control the sensor to perform data acquisition, reconstruct the sensor data based on the data collected by the sensor and the time synchronization signal, generate synchronously sampled sensor data and send it to the data acquisition terminal.

9. The high-precision wireless synchronous trigger acquisition method according to claim 8, characterized in that: All calculations and control processes of the data acquisition terminal are completed in the first MCU processing unit. The specific implementation process of the data acquisition terminal includes: Step 101, parameter initialization, configuration of the maximum coverage distance of the data acquisition terminal and the output period T of the synchronization trigger signal TRIG; Step 102, calculating the delay from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance of the data acquisition terminal; Step 103, starting a first cycle timer according to the output cycle T of the synchronization trigger signal TRIG; Step 104, in the first periodic timer interruption, according to the delay of outputting the synchronization trigger signal TRIG in step 102, starting the first delay timer, and controlling the wireless transceiver to transmit the time synchronization signal; Step 105, generating a synchronous trigger signal TRIG in the first delay timer interrupt to control the sensor to collect data; Step 106, waiting for the sensor to collect data in the main thread, when the sensor collects data, reading the sensor collected data and reporting the sensor collected data, the main thread loops to execute step 106; The data acquisition terminal periodically generates a synchronous trigger signal TRIG through the cooperation of the first periodic timer 1 and the first delay timer 2 to trigger the sensor to collect data.

10. The high-precision wireless synchronous trigger acquisition method according to claim 8, characterized in that: All calculations and control processes of the sensor acquisition terminal are completed in the second MCU processing unit. The specific implementation process of the sensor acquisition terminal includes: Step 201, parameter initialization, configuration of the maximum coverage distance D of the sensor acquisition terminal, the distance d from the sensor acquisition terminal to the data acquisition terminal, and the output period T of the synchronization trigger signal TRIG; Step 202, calculating the delay t4 from transmitting the time synchronization signal to outputting the synchronization trigger signal TRIG according to the maximum coverage distance D of the sensor acquisition terminal; Step 203, calculating the delay parameter t5 according to the distance d from the sensor acquisition terminal to the data acquisition terminal; Step 204, calculating the delay parameter t3 according to the output period T of the synchronization trigger signal TRIG; Step 205, waiting to receive the time synchronization signal of the data acquisition terminal, when the second wireless transceiver receives the time synchronization signal of the data acquisition terminal, a receiving interrupt is generated, and the second MCU processing unit responds to the receiving interrupt; Step 206, in the receiving interrupt, according to the output period T of the synchronization trigger signal TRIG and the local clock count value, calculate the difference between the output frequency of the voltage-controlled crystal oscillator and the frequency of the crystal oscillator of the data acquisition terminal, based on the difference, adjust the output voltage of the DAC digital-to-analog converter so that the output frequency of the voltage-controlled crystal oscillator is the same as the frequency of the crystal oscillator of the data acquisition terminal, and at the same time start the second delay timer according to the parameter t5, and start the third delay timer according to the parameter t3; Step 207, generating a synchronous trigger signal TRIG in the second delay timer interrupt to control the sensor to collect data; Step 208: Control the second wireless transceiver to transmit a time synchronization signal for relaying in the third delay timer interrupt.

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