CN217384130U

CN217384130U - Miniaturized remote wireless strain tester

Info

Publication number: CN217384130U
Application number: CN202123000486.3U
Authority: CN
Inventors: 孙海波
Original assignee: Tongquan Technology Jiaxing Co ltd
Current assignee: Tongquan Technology Jiaxing Co ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2022-09-06
Anticipated expiration: 2031-11-29

Abstract

The utility model discloses a miniaturized remote wireless strain tester, including simulation conditioning module, AD collection module, CPU module, wireless communication module and power module, foil gage or strain gauge sensor are connected to simulation conditioning module's input and simulation conditioning module's output with AD collection module's input electric connection, AD collection module's output with the input electric connection of CPU module, the CPU module with wireless communication module electric connection. The utility model discloses a miniaturized remote wireless strain tester to the wiring that current traditional stress strain tester and current wireless stress strain tester exist inconvenient, wireless transmission distance is near, the consumption is high, bulky, the not long above-mentioned problem of stand-by time, provides a miniaturized remote wireless strain tester.

Description

Miniaturized remote wireless strain tester

Technical Field

The utility model belongs to the technical field of the wireless test of meeting an emergency, concretely relates to miniaturized remote wireless strain tester.

Background

The resistance strain gauge is a common stress-strain measuring sensor, and can convert the structural strain change into resistance change, and the stress change of the structure can be calculated by measuring the resistance change through an electronic circuit. When stress testing is carried out on some large structures such as bridges, cranes, engineering machinery and amusement equipment, the traditional stress-strain testing instrument needs to carry out long-distance and complex wiring, the field installation is inconvenient, and the small analog signals of the strain gauges are interfered and the data reading is influenced because the long-distance wiring is often caused.

Compared with the traditional stress-strain measurement technology, the wireless measurement technology can greatly simplify field wiring, is flexible and convenient to use, and greatly reduces signal interference caused by long cables in wireless digital data transmission. However, the existing wireless test equipment (CN 214308694U, a stress wireless strain tester, CN 105547139A, a wireless strain measurement system based on WIFI) generally adopts standard communication protocols such as WIFI, bluetooth, zigbee, etc., and has the disadvantages of short transmission distance, large equipment volume, high power consumption, short standby time, and inconvenience for field test.

Therefore, the above problems are further improved.

SUMMERY OF THE UTILITY MODEL

A primary object of the utility model is to provide a miniaturized remote wireless strain tester, to the wiring that current traditional stress strain tester and current wireless stress strain tester exist inconvenient, wireless transmission distance is near, the consumption is high, bulky, the not long above-mentioned problem of stand-by time, a miniaturized remote wireless strain tester has been proposed.

In order to achieve the above object, the utility model provides a miniaturized remote wireless strain tester, including simulation conditioning module, AD collection module, CPU module, wireless communication module and power module, wherein:

the input end of the analog conditioning module is connected with a strain gauge or a strain sensor, the output end of the analog conditioning module is electrically connected with the input end of the AD acquisition module (used for realizing AD data acquisition of analog signals), the output end of the AD acquisition module is electrically connected with the input end of the CPU module (through an SPI interface), and the CPU module is electrically connected with the wireless communication module (connected through the SPI interface) and used for realizing wireless data transceiving;

the power supply module is electrically connected with the analog conditioning module, the AD acquisition module, the CPU module and the wireless communication module respectively (the power supply module is used for realizing the charge and discharge management of the battery and supplying power to other modules).

As a further preferred technical solution of the above technical solution, the analog conditioning module includes a bridge circuit, a dial switch, an instrumentation amplifier U5, a DA chip U9, a voltage follower U8, and a frequency modulation filter, wherein:

the bridge circuit is electrically connected with the dial switch (the bridge circuit and the dial switch realize the switching of a full bridge circuit, a quarter bridge circuit and a half bridge circuit);

the FM filter circuit comprises an analog switch U6 and a capacitor network, wherein the analog switch U6 is electrically connected with the capacitor network (the adjustable frequency filter realizes a second-order low-pass filter with different cut-off frequencies by using the analog switch and the capacitor network).

The output end of the DA chip U9 is electrically connected with the REF end of the instrumentation amplifier U5 through the voltage follower U8, and the input end of the DA chip U9 is electrically connected with the control end of the CPU module (the strain balance function is realized through an IIC interface).

As a further preferable technical solution of the above technical solution, the miniaturized remote wireless strain gauge further includes a storage module and a USB module, and the storage module and the USB module are electrically connected to the CPU module, respectively.

As a further preferable technical solution of the above technical solution, the CPU module includes a processor chip U1, and the AD acquisition module includes an AD converter U7, where:

the processor chip U1 is electrically connected with the DA chip U9 through an IIC interface, the output end of the instrumentation amplifier U5 is electrically connected with the input end of the analog switch U6, the output end of the analog switch U6 is electrically connected with the input end of the AD converter U7, and the output end of the AD converter U7 is electrically connected with the input end of the processor chip U1 through an SPI interface.

As a further preferred technical solution of the above technical solution, the storage module includes a storage chip U2, and the power supply module includes a charging chip U4 and a power supply chip U3, wherein:

the storage chip U2 is electrically connected to the processor chip U1 through an SPI interface, the USB module (USB interface) is electrically connected to the charging chip U4, the charging chip U4 is connected to the input end of a battery, and the power supply chip U3 is connected to the output end of the battery.

As a further preferable technical solution of the above technical solution, the 2 pin of the DA chip U9 is electrically connected to the positive input terminal of the voltage follower U8, the output terminal and the negative input terminal of the voltage follower U8 are electrically connected, and the output terminal of the voltage follower U8 is electrically connected to the 5 pin (REF) of the instrumentation amplifier U5;

the 6 pins of the instrumentation amplifier U5 are electrically connected with the positive input end of an operational amplifier UA sequentially through a resistor R3 and a resistor R4, the common end of the resistor R3 and the resistor R4 is electrically connected with the 8 pins of the analog switch U6, the positive input end of the operational amplifier UA is electrically connected with the 9 pins of the analog switch U6, the output end of the operational amplifier UA is electrically connected with the 4 pins of the analog switch U6 through a capacitor C10, the 5 pins of the analog switch U6 are electrically connected with the output end of the operational amplifier UA through a capacitor C11, the 6 pins of the analog switch U6 are electrically connected with the output end of the operational amplifier UA through a capacitor C13, and the 7 pins of the analog switch U6 are electrically connected with the output end of the operational amplifier UA through a capacitor C15;

the output end of the operational amplifier UA is also electrically connected with the 3-pin of the AD converter U7.

The beneficial effects of the utility model reside in that:

1. the wireless remote transmission can be realized, and the transmission distance is more than 500 meters in open. The high-power wireless radio frequency module is adopted, so that the wireless transmission distance can be increased, and the device is very suitable for application occasions in the field of field testing.

2. The volume is small. A miniaturized remote wireless strain tester has a volume of 68mm multiplied by 53mm multiplied by 29mm and a weight of less than 200g, and meets the use occasions of most structural stress tests.

3. The power consumption is low, and the remote sleep and wake-up can be realized. Through low-power-consumption control strategies such as periodic signal acquisition and analog power supply closing, the working time of the wireless sensor can be greatly prolonged. A miniaturized and remote wireless strain tester has no switch button, can be remotely switched on and off and collected through wireless instructions, and is more suitable for field remote testing.

4. And (5) synchronous data acquisition. A plurality of A/D acquisition chips are adopted for synchronous acquisition, and wireless instructions are used for realizing synchronous acquisition, so that the synchronism of multi-channel data acquisition is ensured.

6. Can be compatible with static and dynamic strain acquisition. A plurality of A/D acquisition chips are adopted for synchronous acquisition, the highest sampling rate can reach 5kHz, and the method is compatible with static and dynamic strain acquisition and other applications.

Drawings

Fig. 1 is a schematic structural diagram of a miniaturized remote wireless strain gauge of the present invention.

Fig. 2 is a chip connection diagram of a miniaturized remote wireless strain gauge of the present invention.

Fig. 3 is the utility model discloses a miniaturized remote wireless strain tester's simulation conditioning module and AD collection module circuit diagram.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents and other technical solutions without departing from the spirit and scope of the invention.

The utility model discloses a miniaturized remote wireless strain tester combines preferred embodiment below, further describes utility model's concrete embodiment.

In the embodiment of the present invention, those skilled in the art will note that the strain gauge, the strain gauge sensor, the battery, and the like according to the present invention can be regarded as the prior art.

Preferred embodiments.

The utility model discloses a miniaturized remote wireless strain tester, including simulation conditioning module, AD collection module, CPU module, wireless communication module and power module, wherein:

Specifically, the analog conditioning module includes a bridge circuit, a dial switch, an instrumentation amplifier U5, a DA chip U9, a voltage follower U8, and a frequency modulation filter, wherein:

More specifically, the miniaturized remote wireless strain tester further comprises a storage module and a USB module, wherein the storage module and the USB module are electrically connected with the CPU module respectively.

Further, the CPU module includes a processor chip U1, and the AD acquisition module includes an AD converter U7, where:

Further, the memory module comprises a memory chip U2, and the power supply module comprises a charging chip U4 and a power supply chip U3, wherein:

Preferably, the 2 pin of the DA chip U9 is electrically connected to the positive input terminal of the voltage follower U8, the output terminal and the negative input terminal of the voltage follower U8 are electrically connected, and the output terminal of the voltage follower U8 is electrically connected to the 5 pin (REF) of the instrumentation amplifier U5;

the 6 pins of the instrumentation amplifier U5 are electrically connected with the positive input end of an operational amplifier UA sequentially through a resistor R3 and a resistor R4, the common connection end of the resistor R3 and the resistor R4 is electrically connected with the 8 pins of the analog switch U6, the positive input end of the operational amplifier UA is electrically connected with the 9 pins of the analog switch U6, the output end of the operational amplifier UA is electrically connected with the 4 pins of the analog switch U6 through a capacitor C10, the 5 pins of the analog switch U6 are electrically connected with the output end of the operational amplifier UA through a capacitor C11, the 6 pins of the analog switch U6 are electrically connected with the output end of the operational amplifier UA through a capacitor C13, and the 7 pins of the analog switch U6 are electrically connected with the output end of the operational amplifier UA through a capacitor C15;

the output end of the operational amplifier UA is also electrically connected with the 3 pin of the AD converter U7.

Preferably, the principle of the utility model is that:

the device comprises an analog conditioning module, an AD acquisition module, a CPU module, a storage module, a wireless communication module, a USB module and a power supply module. The front end of the analog conditioning module is connected with a strain gauge or a strain gauge sensor; the analog conditioning module is connected with the AD acquisition module to realize AD data acquisition of analog signals; the AD acquisition module is connected with the CPU module through an SPI interface, and the CPU module is connected with the storage module and the wireless communication module through the SPI interface to realize data storage and wireless data receiving and transmitting; the USB module is connected with the CPU module, and the power supply module realizes battery charging and discharging management and supplies power to other modules.

It is worth mentioning that the analog conditioning module comprises a bridge circuit, a dial switch, an instrument amplifier, a DA chip, a voltage follower and an adjustable frequency filter. The group bridge circuit and the dial switch realize the switching of a full bridge circuit, a quarter bridge circuit and a half bridge circuit, the instrumentation amplifier realizes the amplification of a bridge analog small signal, the output of a DA chip is connected to the REF end of the instrumentation amplifier after passing through a voltage follower, and the DA is controlled by an IIC interface of a CPU module to realize a strain balance function, and the adjustable frequency filter realizes a second-order low-pass filter with different cut-off frequencies by using an analog switch and a capacitor network;

the AD acquisition module is connected with the analog conditioning module, and a high-precision reference power supply is used as a voltage reference for AD acquisition. The AD acquisition module and the analog conditioning module can be provided with a plurality of channels, each channel can be provided with an independent analog conditioning module and an independent AD acquisition module, and different analog conditioning channels can be switched by sharing one channel of AD acquisition module and using an analog switch. The AD acquisition module is connected with the CPU module by using the SPI interface, and is connected with the CPU module by using the daisy chain SPI mode under the condition of parallel acquisition by using a plurality of AD acquisition modules. And a plurality of AD acquisition modules are adopted for synchronous acquisition, so that the synchronism of multi-channel data acquisition can be ensured.

The CPU module is a core control unit of the wireless strain tester and adopts a low-power processor. The CPU module controls the analog conditioning module to realize strain balance, controls the AD acquisition module to realize data acquisition, controls the storage module to realize data storage and reading, controls the wireless communication module to realize wireless data receiving and transmitting, realizes the downloading of stored data through the USB module, and controls the power supply module to realize low-power-consumption operation. The processor runs the wireless protocol stack, controls the wireless communication module to communicate with the remote wireless gateway, receives the instruction of the wireless gateway and sends the acquired data to the wireless gateway, and in the data acquisition process, periodic signal acquisition can be realized according to actual needs, namely, data of T seconds are acquired after each dormancy for a period of time, so that the power consumption of the system can be further reduced.

The storage module uses NAND FALSH memory of SPI interface, and is small in size and easy to integrate, and the storage module realizes data storage function.

The wireless communication module adopts 433MHz or 915MHz or 2.4GHz ISM frequency band, can support high-speed data receiving and transmitting, and can ensure transmission distance.

The USB module uses a 5-core micro USB interface, uses a USB unit in the CPU and uses the USB interface to protect the chip. The USB module realizes the functions of data downloading, charging and resetting. It should be noted that, the general micro USB uses only 1, 2, 3, 5 cores, the signals are VDD, D-, D +, GND respectively, the 4 th core of the micro USB interface is used as the reset signal, and a dedicated reset line is used to implement the reset function, so that the wireless strain tester does not need an external switch.

The power supply module realizes the functions of battery charging and low power consumption management. When a user accesses the USB power supply, the charging chip can automatically charge the battery, and when the battery is fully charged, the charging chip can automatically stop charging. The IO pin of the processor in the CPU module controls the enabling of the power chip, the power of the analog conditioning module and the AD acquisition module can be cut off, and the system automatically sleeps when a user control system sleeps or a user does not operate for 10 minutes, so that the power consumption is saved;

the processor chip U1 controls the DA chip U9 through an IIC interface, the operational amplifier U8 achieves a voltage follower function, the output of the U8 is connected to the REF pin of the instrumentation amplifier U5, and program control strain balance is achieved through an embedded program. Generally, the amplification factor of a strain measurement circuit is large, a user can have large uncertainty when attaching a strain gauge, an input range of the AD can be exceeded after the bridge is amplified, and the purpose of strain balance is to adjust the output of U5 within a normal AD acquisition range. The output data of the U5 is filtered by a second-order low-pass filter composed of an analog switch U6 and a resistor-capacitor network, and the cut-off frequency of the filter can be adjusted by switching capacitors through U6. The output data of the U6 is accessed to the AD converter U7 for collection, and the processor chips U1 and U7 are connected in an SPI mode.

More specifically, the processor chip U1 and the memory chip U2 are connected through an SPI interface. And embedded software in the processor reads and writes pages of the memory chip in an SPI mode to realize the management of stored data.

More specifically, the USB interface is connected to a charging chip U4, the charging chip U4 is connected to a battery, and the power chip U3 converts the voltage of the battery into a system power supply for other modules. The processor chip U1 may control the U3 to turn off power to other modules except the U1 to save power, while the U1 is operating in a low power sleep mode. The U1 is in sleep mode, through the periodic wake-up T3 time every T2 time, if the wake-up command is received from the wireless gateway in the wake-up T3 time, the U1 is in standby mode, otherwise, the sleep mode is continuously entered.

It is worth mentioning that the technical features such as the strain gauge, the strain gauge sensor and the battery that the utility model discloses a patent application relates to should be regarded as prior art, and the concrete structure of these technical features, theory of operation and the control mode that may involve, spatial arrangement mode adopt the conventional selection in this field can, should not be regarded as the invention point of the utility model discloses a place, the utility model discloses a do not do further specifically expand the detailed description.

It will be appreciated by those skilled in the art that changes may be made in the embodiments described above, or equivalents may be substituted for some of the features thereof.

Claims

1. The utility model provides a miniaturized remote wireless strain tester, its characterized in that, includes simulation conditioning module, AD acquisition module, CPU module, wireless communication module and power module, wherein:

the input end of the analog conditioning module is connected with a strain gauge or a strain sensor, the output end of the analog conditioning module is electrically connected with the input end of the AD acquisition module, the output end of the AD acquisition module is electrically connected with the input end of the CPU module, and the CPU module is electrically connected with the wireless communication module;

the power supply module is electrically connected with the analog conditioning module, the AD acquisition module, the CPU module and the wireless communication module respectively;

still include storage module and USB module, storage module with the USB module respectively with CPU module electric connection, power module includes charging chip U4 and power chip U3, the USB module is connected with charging chip U4, and charging chip U4 is connected with the battery, the CPU module includes processor chip U1, and processor chip U1 is used for controlling power chip U3 will remove the power of other modules of processor chip U1 part and close, wireless communication module and long-range wireless gateway communication connection, wireless communication module is used for periodic signal to gather and wireless communication module is used for receiving wireless gateway's instruction and with the data transmission who gathers to wireless gateway.

2. The miniaturized remote wireless strain gauge of claim 1, wherein the analog conditioning module comprises a bridge circuit, a dial switch, an instrumentation amplifier U5, a DA chip U9, a voltage follower U8 and a FM filter, wherein:

the bridge circuit is electrically connected with the dial switch;

the frequency modulation filter circuit comprises an analog switch U6 and a capacitor network, wherein the analog switch U6 is electrically connected with the capacitor network;

the output end of the DA chip U9 is electrically connected with the REF end of the instrumentation amplifier U5 through the voltage follower U8, and the input end of the DA chip U9 is electrically connected with the control end of the CPU module.

3. The miniaturized remote wireless strain gauge of claim 2, wherein the AD acquisition module comprises an AD converter U7, wherein:

4. The miniaturized remote wireless strain gauge of claim 3, wherein the memory module comprises a memory chip U2, wherein:

the storage chip U2 is electrically connected with the processor chip U1 through an SPI interface, the USB module is electrically connected with the charging chip U4, the charging chip U4 is connected with the input end of a battery, and the power supply chip U3 is connected with the output end of the battery.

5. The miniaturized remote wireless strain tester of claim 4, wherein the 2 pin of the DA chip U9 is electrically connected to the positive input terminal of the voltage follower U8, the output terminal and the negative input terminal of the voltage follower U8 are electrically connected, and the output terminal of the voltage follower U8 is electrically connected to the 5 pin of the instrumentation amplifier U5;