Detection device and detection system of MEMS inertial sensor
By dividing the sensor control board into a sensor carrier board and a control board, and using military-grade ultra-low temperature buffer and power supply on the sensor carrier board, combined with the buffer to enhance communication signals, the problem of batch detection of MEMS inertial sensors in ultra-low temperature environments is solved, and a low-cost detection effect is achieved.
Patent Information
- Application Number
- CN202510268137.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-07
- Publication Date
- 2025-06-06
AI Technical Summary
The prior art is difficult to batch-based detection of MEMS inertial sensors in ultra-low temperature environments, and the hardware cost of the detection device is relatively high.
By dividing the sensor control board into a sensor carrier board and a control board, and using military-grade ultra-low temperature buffer and power supply on the sensor carrier board, ensuring normal operation in -55℃ environment, while using industrial-grade devices on the control board, reducing costs. At the same time, the communication signal between the MEMS inertial sensor and the main control device is enhanced through the buffer, and long-distance transmission is realized.
It realizes batch detection of MEMS inertial sensors in ultra-low temperature environments, reduces the hardware cost of the detection device and meets the low-cost needs.
Smart Images
Figure CN120101833A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of detection technology, and in particular to a detection device and a detection system for a MEMS inertial sensor. Background Art
[0002] MEMS (Micro-Electro-Mechanical System) inertial sensors mainly refer to MEMS gyroscopes and MEMS accelerometers. MEMS inertial sensors are electronic components that can measure physical quantities such as angular velocity and acceleration of objects. They are usually used in products such as inertial navigation, motion or attitude detection, involving aviation, aerospace, military industry, automobiles, and industrial equipment.
[0003] Gyroscopes can measure the three-axis angular velocity data of an object moving relative to the measurement coordinate system, and accelerometers can measure the three-axis acceleration data of an object moving in the measurement coordinate system. For example, inertial navigation systems usually use single-axis MEMS inertial sensors or multi-axis MEMS inertial sensor combinations to measure the angular velocity and acceleration data of an object in three-dimensional space, and then use inertial navigation algorithms to solve the measured angular velocity and acceleration data to obtain the object's motion posture.
[0004] MEMS inertial sensors with high precision and capable of working in ultra-low temperature environments have high performance requirements and costs. Manufacturers usually conduct detailed functional and performance tests on MEMS inertial sensors working in ultra-low temperature environments before batch shipment or downstream application manufacturers after purchase. In particular, strict batch testing is required during the batch production process to ensure the quality of sensor components. How to conduct batch testing on MEMS inertial sensors working in ultra-low temperature environments and achieve low cost of testing devices are important issues that need to be solved. Summary of the invention
[0005] The present application provides a detection device and a detection system for a MEMS inertial sensor, which can meet the requirements of detecting the MEMS inertial sensor in an ultra-low temperature environment and reduce the hardware cost of the detection device.
[0006] In a first aspect, the present application provides a detection device for a MEMS inertial sensor, the detection device comprising: a sensor carrier, a control board, a control terminal and a power supply, the sensor carrier comprising at least one first buffer, a first power supply, a test socket and a MEMS inertial sensor, the control board comprising at least one second buffer, a main control device, a second power supply and a communication interface, wherein the low-temperature operating temperature of the first buffer and the first power supply is not lower than -55°C; The first buffer is electrically connected to the test socket, the test socket is electrically connected to the MEMS inertial sensor, the first power supply is electrically connected to the first buffer and the test socket respectively; the main control device is electrically connected to the second buffer and the communication interface respectively, the second power supply is electrically connected to the main control device, the second buffer and the communication interface respectively; the first buffer is electrically connected to the second buffer via a communication cable; the control terminal is electrically connected to the communication interface, and the power supply is electrically connected to the first power supply and the second power supply respectively; The first power supply is used to provide power to the sensor carrier board; the second power supply is used to provide power to the control board; the power supply is used to supply power to the first power supply and the second power supply; the test socket is used to install the MEMS inertial sensor; The control terminal is used to issue a detection instruction for the MEMS inertial sensor and transmit the detection instruction to the communication interface; The communication interface is used to receive the detection instruction and transmit the detection instruction to the main control device; The main control device is used to receive the detection instruction, output a first communication signal for the MEMS inertial sensor according to the detection instruction, and transmit the first communication signal to the second buffer; The second buffer is used to enhance the first communication signal to obtain a second communication signal, and transmit the second communication signal to the MEMS inertial sensor, so that the MEMS inertial sensor measures acceleration and angular velocity and outputs a third communication signal; The first buffer is used to receive the third communication signal, enhance the third communication signal, obtain a fourth communication signal, and transmit the fourth communication signal to the main control device; The main control device is further used to receive the fourth communication signal, obtain measurement data of the MEMS inertial sensor according to the fourth communication signal, and transmit the measurement data to the communication interface; The communication interface is further used to receive the measurement data and transmit the measurement data to the control terminal; The control terminal is also used to receive the measurement data and analyze the measurement data to obtain the detection result.
[0007] In the present application, the sensor control board in the prior art is divided into a sensor carrier board and a control board, and the first buffer and the first power supply on the sensor carrier board are military-grade devices, because they have a lower low-temperature operating temperature, which can ensure that the sensor carrier board can work normally in an ultra-low temperature environment of -55°C, and the components on the control board are industrial-grade devices, and do not need to work in an ultra-low temperature environment. In addition, the driving ability of the communication signal between the MEMS inertial sensor and the main control device is enhanced by the first buffer and the second buffer, so as to achieve the purpose of long-distance transmission, ensure that the sensor carrier board and the control board can communicate normally, and meet the detection requirements of the MEMS inertial sensor in an ultra-low temperature environment. Since the control board in the present application does not need to use high-cost military-grade MCU and communication chips, the hardware cost of the detection device can be greatly reduced.
[0008] In a possible design, the low-temperature operating temperature of the main control device, the second buffer, the second power supply and the communication interface is not lower than -40°C.
[0009] In a possible design, 9 to 12 test sockets are provided on the sensor carrier.
[0010] In a possible design, the main control device communicates with the MEMS inertial sensor via an SPI bus protocol.
[0011] In one possible design, the communication interface is an RS232 communication chip, an RS422 communication chip or a USB communication chip.
[0012] In one possible design, the main control device communicates with the communication interface via a UART bus protocol, an RS422 bus protocol, or a USB bus protocol.
[0013] In a possible design, detection software is installed on the control terminal; The detection software is used to calculate and analyze the measurement data of the MEMS inertial sensor and output the detection result.
[0014] In a possible design, the power supply is a power adapter.
[0015] In a second aspect, the present application provides a detection system for a MEMS inertial sensor, comprising: a high and low temperature test chamber and the detection device for the MEMS inertial sensor in the first aspect.
[0016] In a possible design, the sensor carrier board is placed inside the high and low temperature test box, and the control board, the control terminal and the power supply are placed outside the high and low temperature test box.
[0017] The beneficial effects provided in the above-mentioned second aspect and various possible designs of the above-mentioned second aspect can refer to the beneficial effects brought about by the above-mentioned first aspect and various possible implementation methods of the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a structural schematic diagram of a detection device of a MEMS inertial sensor in the prior art; Figure 2 It is a structural schematic diagram of a detection system of a MEMS inertial sensor in the prior art; Figure 3 A schematic diagram of the structure of a detection device of a MEMS inertial sensor according to an embodiment of the present application; Figure 4 A schematic diagram of the structure of a sensor carrier board according to an embodiment of the present application; Figure 5 This is a schematic diagram of the control panel structure of an embodiment of the present application; Figure 6 A schematic diagram of the structure of a detection system of a MEMS inertial sensor according to an embodiment of the present application. DETAILED DESCRIPTION
[0019] In this application, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c alone can mean: a alone, b alone, c alone, a and b in combination, a and c in combination, b and c in combination, or a, b, and c in combination, where a, b, and c can be single or multiple. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.
[0020] The directions or positional relationships indicated by terms such as "center", "longitudinal", "lateral", "up", "down", "left", "right", "front", and "back" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device or device referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.
[0021] The terms "connected" and "connected" should be understood in a broad sense. For example, the "connected" or "connected" of a circuit structure can refer to not only physical connection, but also electrical connection or signal connection. For example, it can be directly connected, that is, physically connected, or indirectly connected through at least one intermediate device, as long as the circuit is connected, or it can be the internal connection of two devices; signal connection can refer to signal connection through a circuit or through a media medium, such as radio waves. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0022] MEMS inertial sensors are tested in batches before leaving the factory. In consideration of testing methods and costs, the existing technology mainly conducts testing and random inspections at room temperature. But in fact, high-precision ultra-low temperature MEMS inertial sensors can work at -55℃, which can reach military grade, far better than the low-temperature working effect of ordinary industrial grade devices. However, the existing technology cannot achieve ultra-low temperature batch testing for ultra-low temperature MEMS inertial sensors.
[0023] The testing process for MEMS inertial sensors is as follows: after the power supply is supplied to the testing device, the electronic components on the testing device are powered on and run, the MCU on the testing device drives the MEMS inertial sensor through the SPI bus, obtains the measurement data of the MEMS inertial sensor, uploads the measurement data to the computer through the communication interface and communication cable, calculates and analyzes the measurement data through the testing software in the computer, and finally makes a judgment on the quality of the MEMS inertial sensor to be tested. The testing environment for MEMS inertial sensors can be divided into low temperature testing, normal temperature testing and high temperature testing, and low temperature testing and high temperature testing require the use of a high and low temperature box in conjunction with the testing device to achieve the purpose of testing.
[0024] See also Figure 1 , Figure 1 It is a detection device of a MEMS inertial sensor in the prior art. Figure 1 As shown, the detection device includes a sensor control board, a computer and a power supply. The sensor control board is provided with a MEMS inertial sensor, a test socket, an MCU (Microcontroller Unit), a communication interface and a secondary power supply.
[0025] The MCU on the sensor control board drives the MEMS inertial sensor through the SPI bus, obtains the measurement data of the MEMS inertial sensor, and uploads the measurement data to the computer through the communication interface and communication cable for data analysis.
[0026] The test socket is installed on the sensor control board, and a pin is provided at the bottom. After the test socket is installed, it is electrically connected to the sensor control board. A cavity for installing the MEMS inertial sensor is provided inside the test socket, so that the MEMS inertial sensor can be replaced at any time. A pin is provided inside the cavity. When the MEMS inertial sensor is installed on the test socket, the MEMS inertial sensor can be electrically connected to the sensor control board. The sensor control board communicates with the computer through the RS232 or USB (Universal Serial Bus) communication bus protocol.
[0027] The power supply is used to convert AC mains power into DC low voltage power to provide DC power for the sensor control board.
[0028] The secondary power supply is the power supply of the sensor control board, providing secondary DC power supply for various electronic components on the sensor control board.
[0029] Figure 1 Reference numeral 101 is a connection pin between the test socket and the MEMS inertial sensor, including: an SPI bus, a power line, and a control signal line of the MEMS inertial sensor.
[0030] Figure 1 Reference numeral 102 is a connecting pin between the sensor control board and the test socket, including: an SPI bus, a power line, and a control signal line of the MEMS inertial sensor.
[0031] Figure 1 103 is a communication cable between the sensor control board and the computer, including: RS232 or USB communication bus, and its length can be about 2 meters.
[0032] Figure 1 Reference numeral 104 is a power cable from the power supply to the sensor control board, and the length of the power cable may be about 2 meters. The power supply usually outputs a 5V DC power supply.
[0033] Figure 1 105 is a communication bus between the communication interface and the MCU, which is usually a UART bus or a USB bus.
[0034] See also Figure 2 , Figure 2 It is a detection system of a MEMS inertial sensor in the prior art. Figure 2 As shown, the high and low temperature test box in the figure is a conventional environmental testing equipment, the temperature inside of which can be set as needed, and can provide high and low temperature test environments for MEMS inertial sensors. Figure 2The test socket and the MEMS inertial sensor installed on the sensor control board communicate with a computer outside the high and low temperature test box via a communication cable (103), and are connected to a power supply outside the high and low temperature test box via a power cable (104).
[0035] In the prior art, when performing high temperature or low temperature testing on a MEMS inertial sensor, it is necessary to place the sensor control board inside a high and low temperature test box and place the computer outside the high and low temperature test box. The high and low temperature box is a medium-to-large-sized device and is usually large in size. Therefore, the required communication cable (103) and power cable (104) are usually about 2 meters in length.
[0036] In the existing detection scheme for MEMS inertial sensors, the MCU and communication interface on the sensor control board mainly use industrial-grade electronic components, and the minimum normal working temperature under low temperature is -40°C. When it is necessary to batch test the working ability of MEMS inertial sensors in ultra-low temperature environments, such as -55°C, the existing technical solutions cannot meet the needs of comprehensive detection of ultra-low temperature MEMS inertial sensors.
[0037] At present, electronic components that can meet the requirements of ultra-low temperature (-55℃) environment operation belong to military-grade components, and the cost of military-grade electronic components is 50 to 200 times higher than that of industrial-grade electronic components. The most expensive military-grade components are MCUs, with a unit price of about several thousand yuan (3,000 to 6,000 yuan), followed by communication chips, with a unit price of about hundreds to thousands of yuan, and finally power supplies and passive devices, with unit prices ranging from tens to hundreds of yuan. Passive devices may include resistors, capacitors, etc. If military-grade components are directly used within the framework of the existing technical solution, for example, military-grade MCU components are used to drive MEMS inertial sensors, and military-grade communication interface chips are used to communicate with computers, the hardware cost of the entire MEMS inertial sensor batch detection device will be extremely high. Therefore, a new technical solution is needed to meet the batch detection of MEMS inertial sensors working in ultra-low temperature environments. The new technical solution must not only meet the detection requirements of MEMS inertial sensors in ultra-low temperature environments, but also meet the requirements of low cost of the detection device.
[0038] In order to solve the above problems existing in the prior art, the present application provides a detection device of a MEMS inertial sensor, see Figure 3 , Figure 3 A detection device for a MEMS inertial sensor, such as Figure 3As shown, the detection device includes: a sensor carrier, a control board, a control terminal and a power supply, the sensor carrier includes at least one first buffer (ultra-low temperature buffer), a first power supply (ultra-low temperature power supply), a test socket and a MEMS inertial sensor, the control board includes at least one second buffer (ordinary buffer), a main control device (MCU), a second power supply (secondary power supply) and a communication interface, wherein the low-temperature operating temperature of the first buffer and the first power supply is not lower than -55°C.
[0039] It can be understood that the first buffer, the first power supply, the second buffer, the main control device, the second power supply and the communication interface in the present application all include functional chips and corresponding peripheral auxiliary devices. For the convenience of description, the present application does not list the peripheral auxiliary devices one by one, and only uses the first buffer, the first power supply, the second buffer, the main control device, the second power supply and the communication interface to represent the functional modules.
[0040] The detection device of the MEMS inertial sensor in the present application is mainly used for batch detection of the MEMS inertial sensors during the production inspection stage.
[0041] The first buffer is electrically connected to the test socket, the test socket is electrically connected to the MEMS inertial sensor, the first power supply is electrically connected to the first buffer and the test socket respectively; the main control device is electrically connected to the second buffer and the communication interface respectively, the second power supply is electrically connected to the main control device, the second buffer and the communication interface respectively; the first buffer is electrically connected to the second buffer through a communication cable; the control terminal is electrically connected to the communication interface, and the power supply is electrically connected to the first power supply and the second power supply respectively.
[0042] The test socket is fixed on the sensor carrier, and is connected to the sensor carrier through the metal ejector pin inside the test socket to achieve electrical connection. A MEMS inertial sensor can be installed in the test socket, and the test socket and the MEMS inertial sensor are connected to each other through the metal ejector pin inside the test socket to achieve electrical connection. The sensor carrier and the MEMS inertial sensor are ultimately electrically connected indirectly through the test socket.
[0043] The first power supply is used to provide power to the sensor carrier board; the second power supply is used to provide power to the control board; the power supply is used to supply power to the first power supply and the second power supply; the test socket is used to install the MEMS inertial sensor.
[0044] The control terminal is used to issue detection instructions for the MEMS inertial sensor and transmit the detection instructions to the communication interface.
[0045] The communication interface is used to receive the detection instruction and transmit the detection instruction to the main control device.
[0046] The main control device is used to receive the detection instruction, output a first communication signal for the MEMS inertial sensor according to the detection instruction, and transmit the first communication signal to the second buffer.
[0047] The second buffer is used to enhance the first communication signal to obtain a second communication signal, and transmit the second communication signal to the MEMS inertial sensor, so that the MEMS inertial sensor measures acceleration and angular velocity and outputs a third communication signal.
[0048] The first buffer is used to receive the third communication signal, enhance the third communication signal, obtain the fourth communication signal, and transmit the fourth communication signal to the main control device.
[0049] The main control device is also used to receive a fourth communication signal, obtain measurement data of the MEMS inertial sensor according to the fourth communication signal, and transmit the measurement data to the communication interface.
[0050] The communication interface is also used to receive measurement data and transmit the measurement data to the control terminal.
[0051] The control terminal is also used to receive measurement data, analyze the measurement data, and obtain detection results.
[0052] The first buffer can enhance the driving capability of the communication signal transmitted from the MEMS inertial sensor to the main control device, and the second buffer can enhance the driving capability of the communication signal transmitted from the main control device to the MEMS inertial sensor. The first buffer can work in an ultra-low temperature environment of -55°C and is a military-grade device. The second buffer is an ordinary industrial or commercial-grade device and does not need to work in an ultra-low temperature environment of -55°C. By enhancing the communication signal between the MEMS inertial sensor and the main control device through the first buffer and the second buffer, the purpose of long-distance communication can be achieved.
[0053] The first power supply can work in an ultra-low temperature environment of -55°C. It is a military-grade device that powers the first buffer and MEMS inertial sensor on the sensor carrier. The second power supply is a common industrial-grade or commercial-grade power chip that powers the main control device, the second buffer, and the communication interface on the control board. Since the operating temperature of the first buffer and the first power supply is -55°C, the sensor carrier can work in an ultra-low temperature environment of -55°C, and the control board does not need to work in an ultra-low temperature environment.
[0054] Compared with the prior art, on the one hand, by dividing the sensor control board in the prior art into a sensor carrier board and a control board, and using military-grade devices for the components on the sensor carrier board, it can be ensured that the sensor carrier board can work normally in an ultra-low temperature environment, while the components on the control board use industrial-grade or commercial-grade devices, and do not need to work in an ultra-low temperature environment. The driving ability of the communication signal between the MEMS inertial sensor and the main control device is enhanced by the first buffer and the second buffer, so as to achieve the purpose of long-distance transmission, ensure that the sensor carrier board and the control board can communicate normally, and meet the detection requirements of the MEMS inertial sensor in an ultra-low temperature environment. On the other hand, the sensor carrier board in the present application only retains the military-grade first buffer and the first power supply, while the MCU and the communication chip on the control board use industrial-grade or commercial-grade devices, without the need to use expensive military-grade devices, which can greatly reduce the hardware cost of the detection device.
[0055] In a possible embodiment, the low-temperature operating temperature of the main control device, the second buffer second power supply and the communication interface is not less than -40°C, and they are industrial-grade or commercial-grade devices.
[0056] In a possible embodiment, 9 to 12 test sockets are arranged on the sensor carrier board. In view of the demand for batch testing, the effect of batch testing of 9 to 12 MEMS inertial sensors at one time can be achieved.
[0057] In a possible embodiment, the main control device communicates with the MEMS inertial sensor through an SPI bus protocol.
[0058] MEMS inertial sensors need to be driven by the SPI signal and control signal of the main control device (MCU), as well as the first power supply (ultra-low temperature power supply) of the sensor carrier to work properly. The first buffer (ultra-low temperature buffer) is welded on the sensor carrier and can work in ultra-low temperature environments, for example, -55°C. The SPI signal output by the MEMS inertial sensor is buffered by the ultra-low temperature buffer to enhance the driving capability of the SPI high-speed signal, so that the SPI signal can be transmitted farther and correctly transmitted to the MCU. The transmission distance can reach about 2 meters, ensuring the normal communication between the MEMS inertial sensor and the MCU. The ultra-low temperature power supply is welded on the sensor carrier and can work in ultra-low temperature environments, for example, -55°C, to power devices such as MEMS inertial sensors and ultra-low temperature buffers. In one example, the control terminal can be a computer or server.
[0059] The main control device (MCU) has an SPI interface and drives the MEMS inertial sensor through the SPI signal to obtain the measurement data of the MEMS inertial sensor. The MCU has the function of communicating with the control terminal (computer). It can transmit the measurement data of the MEMS inertial sensor to the control terminal (computer) through the communication interface chip and the communication cable, and can also perform corresponding operations according to the control instructions sent by the control terminal (computer). The main control device (MCU) has 3~4 groups of SPI interfaces. For batch detection needs, 3~4 groups of SPI buses can be used to drive 9~12 MEMS inertial sensors.
[0060] When the MEMS inertial sensor is tested by the detection device, the control board only needs to work in a normal temperature environment, and the sensor carrier board can work in an ultra-low temperature environment, such as -55°C. In one example, when the MEMS inertial sensor is tested at an ultra-low temperature in a high and low temperature test box, the sensor carrier board needs to be placed in the high and low temperature test box, and the control board needs to be placed outside the high and low temperature test box. This will make the control board and the sensor carrier board far away, and the communication cable connecting the control board and the sensor carrier board is relatively long, about 2 meters. Since the SPI bus is a short-distance high-speed communication bus, its transmission distance does not exceed 0.5 meters. When the SPI signal between the control board and the sensor carrier board is directly transmitted using a communication cable of about 2 meters, the SPI signal waveform will be seriously distorted, thereby causing poor communication between the MCU and the MEMS inertial sensor. Therefore, the SPI communication between the MCU and the MEMS inertial sensor requires a buffer to enhance the driving force of the SPI signal to achieve the purpose of long-distance transmission. In the present application, the driving force of the input signal of the SPI bus is enhanced by the first buffer, and the driving force of the output signal of the SPI bus of the main control device is enhanced by the second buffer. The MCU on the control board can use a longer communication cable to transmit SPI signals to drive the MEMS inertial sensor, thereby achieving the purpose of controlling the MEMS inertial sensor and reading measurement data.
[0061] In a possible embodiment, the communication interface is an RS232 communication chip, an RS422 communication chip or a USB communication chip.
[0062] In a possible embodiment, the main control device communicates with the communication interface via a UART bus protocol, an RS422 bus protocol, or a USB bus protocol.
[0063] The communication interface can be used to convert the UART bus communication signal of the MCU into RS232, RS422 or USB bus communication signal and transmit it to the control terminal (computer).
[0064] In a possible embodiment, detection software is installed on the control terminal; the detection software is used to calculate and analyze the measurement data of the MEMS sensor and output the detection result.
[0065] The control terminal is installed with test software for analyzing the measurement data of the MEMS inertial sensor. It can also issue control instructions based on the test software to control the control board. The control terminal can output the detection results of the MEMS inertial sensor to other display terminals.
[0066] In a possible embodiment, the power supply is a power adapter.
[0067] The power supply is a power adapter that can convert AC power signals into DC power signals to power the first power supply or the second power supply, and provide DC power to the electronic components on the sensor carrier board and the control board through the first power supply and the second power supply.
[0068] In a possible embodiment, the operating temperature of the second buffer, the main control device (MCU), the communication interface, and the second power supply is not lower than -40°C, and they are industrial-grade electronic components, so that the control board of the present application scheme is very low in cost compared to the control board using military-grade components.
[0069] See also Figure 3 The working principle of the detection device of the MEMS inertial sensor in this application is as follows: after the power supply supplies power to the secondary power supply (second power supply) on the control board and the ultra-low temperature power supply (first power supply) on the sensor carrier board, the detection device starts working, and the detection software installed on the control terminal (computer) sends the detection instruction of the MEMS inertial sensor to the MCU of the control board through the communication cable. After receiving the detection instruction, the MCU starts the driver of the MEMS inertial sensor, sends instructions to the MEMS inertial sensor through the SPI bus and the control line, controls the MEMS inertial sensor to measure acceleration and angular velocity, and reads the measurement data of the MEMS inertial sensor through the SPI bus. After the MCU reads the measurement data of the MEMS inertial sensor, it transmits the measurement data to the detection software of the control terminal (computer) through the UART bus or USB bus, and through the communication interface chip and the communication cable. The detection software calculates and analyzes the measurement data, and makes a judgment on the quality of the MEMS inertial sensor to realize batch detection.
[0070] In this application, the MCU and communication interface chip in the prior art are separated from the sensor control board and placed on the control board, and the driving ability of the SPI bus signal between the MCU and the MEMS inertial sensor is enhanced by using a buffer to achieve long-distance communication between the two. Therefore, the control board can work in a normal temperature environment, and the sensor carrier can work in an ultra-low temperature environment of -55°C. The control board and the sensor carrier can work at different temperatures to complete the test, avoiding the use of ultra-low temperature MCU and communication interface chips with extremely high costs, so that the hardware cost of the test device is greatly reduced. In order to achieve the purpose of batch detection, 9 to 12 MEMS inertial sensors can be driven by 3 to 4 groups of SPI buses, so 3 to 4 ultra-low temperature buffers (first buffers) are required on the sensor carrier. In order to ensure the performance of the MEMS inertial sensor, several ultra-low temperature power supplies (first power supplies) are required to power the MEMS inertial sensor. Since the hardware cost of the ultra-low temperature buffer of the sensor carrier is about tens of yuan, its cost is much lower than the cost of the ultra-low temperature MCU and the ultra-low temperature communication chip, the cost of the entire batch detection device in this application is about hundreds of yuan, which meets the low cost demand of the test device.
[0071] See also Figure 3 , Figure 3 201 is the electrical connection interface between the test socket and the MEMS inertial sensor, including: SPI bus, power line and control signal line.
[0072] Figure 3 202 is the electrical connection interface between the ultra-low temperature buffer and the test socket, including: SPI bus and control signal line. The power line is not included, and the power supply of the test socket is provided by the ultra-low temperature power supply.
[0073] Figure 3 207 is a communication cable between the sensor carrier and the control board, which is about 2 meters long. One end of the communication cable is electrically connected to the ultra-low temperature buffer on the sensor carrier, and the other end is electrically connected to the ordinary buffer on the control board.
[0074] Figure 3 206 is a signal connection line between the MCU on the control board and the common buffer, including: an SPI bus and a control signal line.
[0075] Figure 3 205 is a signal connection between the communication interface chip and the MCU, usually a UART bus or a USB bus.
[0076] Figure 3 203 is the communication cable between the control board and the computer, usually RS232 or USB communication bus.
[0077] Figure 3204 is a power cable used by the power supply to supply power to the sensor carrier board and the control board. The power cable first passes through the control board and supplies power to the control board. At the same time, a power supply is separated and supplied to the sensor carrier board through the cable between the control board and the sensor carrier board.
[0078] Figure 4 Schematic diagram of the structure of a sensor carrier board, such as Figure 4 As shown, Figure 4 210 is a test socket that can be used to install MEMS inertial sensors.
[0079] Figure 4 The 211 in it is an ultra-low temperature buffer.
[0080] Figure 4 212 is a communication cable socket, which is used to install the communication cable connecting the sensor carrier board and the control board.
[0081] Figure 4 213 in it is an ultra-low temperature power supply, which provides DC power for the ultra-low temperature buffer and MEMS inertial sensor.
[0082] Figure 4 221 is a circuit board of the sensor carrier.
[0083] Figure 5 A schematic diagram of the structure of a control panel is shown in FIG. Figure 5 As shown, Figure 5 214 is a common buffer.
[0084] Figure 5 215 is a communication cable socket, which is used to install the communication cable connecting the sensor carrier board and the control board.
[0085] Figure 5 The 216 in the figure is MCU.
[0086] Figure 5 217 is a secondary power supply, which provides DC power for MCU, common buffer and communication interface chip.
[0087] Figure 5 218 is a circuit board of the control board.
[0088] Figure 5 219 is a cable socket on the computer side, which is used to install the communication cable connecting the control board and the computer.
[0089] Figure 5 220 is a communication interface chip.
[0090] The present application also provides a detection system for a MEMS inertial sensor, see Figure 6 , Figure 6It is a schematic diagram of the detection system structure of a MEMS inertial sensor, such as Figure 6 As shown, the detection system of the MEMS inertial sensor includes a high and low temperature test box and a detection device of the MEMS inertial sensor.
[0091] In a possible embodiment, the sensor carrier board is placed inside the high and low temperature test box, and the control board, the control terminal and the power supply are placed outside the high and low temperature test box.
[0092] For high-precision MEMS inertial sensors that work at ultra-low temperatures, for example, military-grade MEMS inertial sensors can work at -55°C. When batch testing is required, it is necessary to implement it in an ultra-low temperature working environment of -55°C in a high and low temperature test box. Therefore, a sensor carrier that can work in an ultra-low temperature environment and can achieve batch testing is required, and it must be combined with a control board to achieve the purpose of testing. This application is based on cost considerations. In order to reduce costs, an industrial-grade MCU and communication interface chip are used in this application, and are placed on the control board. The control board is placed outside the high and low temperature box and only needs to work at normal temperature. The sensor carrier is placed inside the high and low temperature test box, and a military-grade ultra-low temperature buffer and ultra-low temperature power supply are used to achieve detection in ultra-low temperature environments. A longer communication cable is required to connect the control board and the sensor carrier. Batch testing in ultra-low temperature environments can be achieved, while achieving the dual purpose of reducing the hardware cost of the detection device.
[0093] The detection device in the present application can realize batch detection of 9 to 12 MEMS inertial sensors in an ultra-low temperature environment at the same time. If the space in the high and low temperature box allows, multiple detection devices can be placed and run simultaneously, which can also improve the detection efficiency to a greater extent.
[0094] See also Figure 6 , Figure 6 207 is the communication cable between the sensor carrier board and the control board, and the length is about 2 meters.
[0095] Figure 6 203 is the communication cable between the control board and the computer, usually RS232 or USB communication bus.
[0096] Figure 6 204 is a power cable for the power supply to supply power to the sensor carrier board and the control board.
[0097] Finally, it should be noted that the above embodiments are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto, and any changes or substitutions within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.
Claims
1. A detection device for a MEMS inertial sensor, characterized in that: The detection device comprises: a sensor carrier, a control board, a control terminal and a power supply, wherein the sensor carrier comprises at least one first buffer, a first power supply, a test socket and a MEMS inertial sensor, and the control board comprises at least one second buffer, a main control device, a second power supply and a communication interface, wherein the low-temperature working temperature of the first buffer and the first power supply is not lower than -55°C; The first buffer is electrically connected to the test socket, the test socket is electrically connected to the MEMS inertial sensor, the first power supply is electrically connected to the first buffer and the test socket respectively; the main control device is electrically connected to the second buffer and the communication interface respectively, the second power supply is electrically connected to the main control device, the second buffer and the communication interface respectively; the first buffer is electrically connected to the second buffer via a communication cable; the control terminal is electrically connected to the communication interface, and the power supply is electrically connected to the first power supply and the second power supply respectively; The first power supply is used to provide power to the sensor carrier board; the second power supply is used to provide power to the control board; the power supply is used to supply power to the first power supply and the second power supply; the test socket is used to install the MEMS inertial sensor; The control terminal is used to issue a detection instruction for the MEMS inertial sensor and transmit the detection instruction to the communication interface; The communication interface is used to receive the detection instruction and transmit the detection instruction to the main control device; The main control device is used to receive the detection instruction, output a first communication signal for the MEMS inertial sensor according to the detection instruction, and transmit the first communication signal to the second buffer; The second buffer is used to enhance the first communication signal to obtain a second communication signal, and transmit the second communication signal to the MEMS inertial sensor, so that the MEMS inertial sensor measures acceleration and angular velocity and outputs a third communication signal; The first buffer is used to receive the third communication signal, enhance the third communication signal, obtain a fourth communication signal, and transmit the fourth communication signal to the main control device; The main control device is further used to receive the fourth communication signal, obtain measurement data of the MEMS inertial sensor according to the fourth communication signal, and transmit the measurement data to the communication interface; The communication interface is further used to receive the measurement data and transmit the measurement data to the control terminal; The control terminal is also used to receive the measurement data and analyze the measurement data to obtain the detection result.
2. The detection device according to claim 1, characterized in that: The low-temperature operating temperature of the main control device, the second buffer, the second power supply and the communication interface is not lower than -40°C.
3. The detection device according to claim 1, characterized in that: The sensor carrier is provided with 9 to 12 test sockets.
4. The detection device according to claim 1, characterized in that: The main control device communicates with the MEMS inertial sensor via the SPI bus protocol.
5. The detection device according to claim 1, characterized in that: The communication interface is an RS232 communication chip, an RS422 communication chip or a USB communication chip.
6. The detection device according to claim 1, characterized in that: The main control device communicates with the communication interface via a UART bus protocol, an RS422 bus protocol or a USB bus protocol.
7. The detection device according to claim 1, characterized in that: The control terminal is installed with detection software; The detection software is used to calculate and analyze the measurement data of the MEMS inertial sensor and output the detection result.
8. The detection device according to claim 1, characterized in that: The power supply is a power adapter.
9. A detection system for a MEMS inertial sensor, characterized in that: include: A high and low temperature test box and a detection device for a MEMS inertial sensor as claimed in any one of claims 1 to 8.
10. The detection system according to claim 9, characterized in that: The sensor carrier is placed inside the high and low temperature test box, and the control board, the control terminal and the power supply are placed outside the high and low temperature test box.