An angle measurement system based on sample measurements

Abstract

The application discloses an angle measurement system based on sample measurement, which is used for angle measurement of a rotating measured target, and a rotation control system is arranged on the measured target and comprises a plurality of inclination sensors and a mounting tool, wherein the inclination sensors are N in number, are respectively installed at N different positions of the measured target, N-1 sample measurement values are obtained, and the last angle measurement value is obtained after taking the angle measurement results of the N-1 positions as calibration samples; a collection control device is used for adapting to a first power supply condition to supply power to the inclination sensors, performing communication management on the inclination sensors, and converting serial communication into Ethernet communication; a host computer is used for man-machine interaction, and cooperates with the rotation control system of the measured target to measure, store and display the movement of the measured target; and a test cable is used for connection between the collection control device and the plurality of inclination sensors.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of angle measurement sensor, and particularly relates to an angle measurement system based on sample measurement. BACKGROUND

[0002] In aerospace and military application scenarios, the attitude information collection of many devices as key devices of comprehensive application is particularly important. For example, a support of a to-be-measured object, under some working conditions, the bottom plate undulates unevenly, the different positions of the base will appear transverse and longitudinal inclination angles, and the support has a coupling relationship with the working surface in the processes of lifting, pushing, lowering and moving, so that the pitch state often occurs, and the attitude will change accordingly, especially when the support is pushed to a certain working period, the attitude of the support will change more drastically, and if the attitude information of the installed tooling cannot be obtained at this time, the to-be-measured object and the sensor itself mechanism will be damaged.

[0003] At present, MEMS inclination angle sensors are widely used in low-cost attitude angle measurement. The inclination angle sensor measures the angle in a static and uniform motion state, but is easily affected by other accelerations. If variable acceleration motion occurs in the lifting process of the to-be-measured object, the inclination angle sensor perceives the superposition value of inertial acceleration and motion acceleration. Due to the influence of motion acceleration, the inclination angle measurement is inaccurate. Of course, a MEMS gyroscope can also be used for replacement, which has good dynamic characteristics and is not affected by acceleration, and can make up for the deficiency of the inclination angle sensor affected by the motion acceleration. However, the gyroscope is easily disturbed by noise, vibration and temperature change and other factors to produce random drift error, and in addition, the sensor itself has a constant drift error. With the passage of time, there is a certain cumulative calculation error in the deflection angle, and a single gyroscope cannot guarantee the accuracy of long-time attitude angle measurement.

[0004] Of course, the prior art also uses, for example, complementary filtering algorithm and Kalman filtering algorithm to fuse and correct the sensor data. However, since the basic data of these algorithms does not come from the actual measurement result of the position angle, there is still a large error between the calibration and correction and the actual measurement process, and the calculated angle still differs from the actual situation.

[0005] Therefore, the prior art described above indeed needs to propose a better solution. SUMMARY

[0006] The purpose of the present application is to provide an angle measurement system based on sample measurement, which uses a traditional inclination angle sensor, uses the angle measurement results of multiple positions as calibration samples, and then carries out subsequent angle measurement, so that the angle measurement result is more accurate.

[0007] The first aspect of the present application provides an angle measurement system based on sample measurement for angle measurement of a rotating measured target, wherein a rotation control system is arranged on the measured target, and the angle measurement system comprises:

[0008] a plurality of inclination sensors 1 and installation tools, wherein the inclination sensors are N in number and are respectively installed at N different positions of the measured target, N-1 sample measurement values are obtained, and the angle measurement results of the N-1 positions are taken as calibration samples to obtain the last angle measurement value;

[0009] a collection control device 2 for adapting the first power supply condition to supply power to the inclination sensors, for communication management of the inclination sensors, and for converting serial communication into Ethernet communication;

[0010] a host computer 3 for human-computer interaction, for measuring, storing and displaying the motion of the measured target in cooperation with the rotation control system of the measured target; and

[0011] a test cable for connecting the collection control device 2 and the plurality of inclination sensors 1.

[0012] Preferably, the inclination sensor measures the attitude information of the measured target relative to the geodetic coordinate system based on the principle of gravity measurement, and projects the attitude information in the geodetic coordinate system onto the surface of the measured target, calculates the relative angle change of the measured target through relative angle change calculation, measures the gravity component using an accelerometer, and thus obtains the included angle between the measurement axis and the gravity, the direction of the gravitational acceleration g is always vertically downward, when the measurement axis is horizontal, the gravity component measured by the accelerometer is zero, when the accelerometer is vertically upward, the measurement value is equal to the gravity, and when the measurement axis has an inclined angle with the horizontal plane, the accelerometer measures the gravity component in the direction;

[0013] The X-axis accelerometer output has the following relationship with the gravitational acceleration g:

[0014] (1) ;

[0015] In formula (1), is the acceleration information of the X-axis accelerometer output, g is the acceleration value with gravity as the reference, is the inclination angle of the sensor, that is, the inclination angle of the measured target;

[0016] Therefore, the angle value information can be solved:

[0017] (2).

[0018] The inclination sensor measures the attitude angle, and the attitude information in the geodetic coordinate system is projected onto the surface of the measured target, and the relative angle change of the measured target is calculated through the relative angle change calculation.

[0019] Preferably, the system comprises four inclination sensors installed on the surface of the measured target and the key parts affecting the attitude.

[0020] Preferably, the inclination sensor 1 is a MEMS inclination sensor.

[0021] Preferably, the first power supply condition is a 220V / 50Hz power supply condition, and the acquisition control device is composed of a power module 21, a gateway 22, a splitter 23, a box body 24, a switch 25, a front panel 26, a rear panel 27 and an upper cover plate 28; the power module 21 is used to convert 220V / 50Hz power supply into 12V power supply to supply power to the gateway and the inclination sensor respectively; the gateway 22 is used to convert RS485 communication into Ethernet communication; the splitter 23 is used to integrate multiple signals and power supply; the switch 25 is arranged on the front panel 26 of the box body, and is used to power on the whole system; the rear panel 27 is provided with a plurality of connectors, and the plurality of connectors are respectively used for external power supply, used for power supply and communication with the inclination sensor, and used for communication with the upper computer.

[0022] Preferably, the plurality of connectors include:

[0023] A socket network port connector 271 is used for communication with the upper computer 3;

[0024] A 5-core metal socket 272 is used for communication with the inclination sensor 1;

[0025] A power supply line 273 is used for external power supply and power supply of the inclination sensor 1.

[0026] Preferably, the power module is a 220V / 50Hz AC to DC power module, the power input of the power module is AC 220V / 50Hz, the power output is DC 12V / 10A, the protection form is overcurrent protection, overvoltage protection and overtemperature protection, the working temperature range is-20℃~60℃, and the storage temperature range is-40℃~85℃.

[0027] Preferably, the gateway 22 is an RS485 to Ethernet module, which can realize communication forwarding of up to not more than 255 RS485 nodes by using the RS485 bus mode, and the communication switching module includes: supporting RS232, RS422 and RS485 protocols; supporting UDP protocol; the power supply voltage range is 9V~35V; the working temperature range is-20℃~60℃; and the storage temperature range is-40℃~85℃.

[0028] Preferably, the host computer 3 is connected with the gateway 22 through Ethernet, and the transmission protocol uses UDP transmission; the host computer software is divided into three modules, namely, a device list module, a test operation module and a record query module. The device list module is used for updating and maintaining device information; the test operation module is divided into a measurement site selection submodule, a device initialization submodule, an installation position determination submodule, a start calibration submodule, a zero value acquisition submodule, a start / stop measurement submodule and a reset submodule according to a test flow; and the record query module is used for querying and exporting measurement data.

[0029] As a preferred embodiment, the host computer software flow includes: modifying the device through the device list module; viewing and exporting the list through the record query module; during testing, selecting the measurement site and simultaneously pressing the initialization button, implementing the power-on handshake, if the handshake result is completed, detecting whether there is an exception, if there is no exception, confirming whether to continue through a pop-up box, if continuing, starting the power-on initialization, if confirming not to continue, returning to the initialization button; if the handshake result is abnormal, starting the timeout mechanism according to the interval time, in the case of timeout, performing the exception identification and returning to the initialization button, and in the case of not timeout, returning to the power-on handshake; after determining that the power-on initialization is completed, selecting the working condition and performing the position determination, selecting the calibration mode according to the sample measurement result, the calibration mode including no calibration, last calibration or calibration; sending the calibration command based on the selected calibration mode, if the calibration is successful, returning the zero value and starting the measurement, if the calibration fails, recalibrating; after determining that the zero value is returned, starting the measurement, selecting the continuous or single-step measurement mode, for the continuous measurement mode, manually ending the measurement and resetting, and for the single-step measurement mode, automatically ending the measurement.

[0030] The measurement system provided by the application has the following beneficial technical effects:

[0031] (1) The acquisition control part, the power supply part and the inclination sensor are integrated together, especially the switching value and the analog value output are integrated, the degree of integration is high, and the interference and real-time synchronization of signal processing are greatly improved, thereby optimizing the protection characteristics and sealing performance of the whole sensor and the accuracy of signal detection;

[0032] (2) The angle measurement system based on sample measurement adopts the traditional inclination sensor, uses the angle measurement results of multiple positions as calibration samples to carry out subsequent angle measurement, so that the angle measurement result is more accurate, and the measurement accuracy can meet the measurement requirement of 0.1°. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The system structure schematic diagram according to the preferred embodiment of the application is shown;

[0034] Figure 2 Fig. 1 is a schematic diagram of an accelerometer angle measurement principle according to a preferred embodiment of the present application;

[0035] Figure 3 Fig. 2 is a schematic diagram of a collection control device structure principle according to a preferred embodiment of the present application;

[0036] Figure 4 Fig. 3 is a schematic diagram of an upper computer software module division structure according to a preferred embodiment of the present application;

[0037] Figure 5 Fig. 4 is a schematic diagram of an upper computer software flow according to a preferred embodiment of the present application;

[0038] Figure 6 Fig. 5 is a schematic diagram of an electronic device according to a preferred embodiment of the present application. DETAILED DESCRIPTION

[0039] The specific embodiments of the present application are described in further detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application, but are not used to limit the scope of the present application.

[0040] Referring to Figure 1 , the present embodiment provides a sample measurement based angle measurement system for angle measurement of a rotating measured target, a rotation control system is arranged on the measured target, comprising:

[0041] a plurality of inclination sensors and mounting tools, wherein the inclination sensors are N in number, are respectively installed at N different positions of the measured target, obtain N-1 sample measurement values, and obtain a last angle measurement value after the angle measurement results of the N-1 positions are taken as calibration samples; the inclination sensors measure the attitude information of the measured target relative to the geodetic coordinate system based on the gravity measurement principle, and project the attitude information in the geodetic coordinate system onto the surface of the measured target, and obtain the relative angle change amount of the measured target through relative angle change calculation, the measurement principle is as shown in Figure 2 The accelerometer is used to measure the gravity component, so as to obtain the included angle of the measurement axis relative to the gravity. The direction of the gravity acceleration g is always vertically downward, when the measurement axis is horizontal, the gravity component measured by the accelerometer is zero, when the accelerometer is vertically upward, the measurement value is equal to the gravity. When the measurement axis has an inclined angle with the horizontal plane, the accelerometer measures the component of the gravity in the direction.

[0042] The X-axis accelerometer output has the following relationship with the gravity acceleration g:

[0043] (1);

[0044] In formula (1), is the acceleration information of X-axis accelerometer output, g is the acceleration value with gravity as reference, is the sensor tilt angle, that is, the tilt angle of the measured target.

[0045] Thus, the angle value information can be calculated:

[0046] (2).

[0047] Therefore, the measurement of angle information is realized on the basis of acceleration principle, which takes gravity as input vector to determine the state of the object in space, and then reflects the angle of the object.

[0048] On the basis of the attitude angle measurement of the tilt angle sensor, the attitude information in the geodetic coordinate system is projected onto the surface of the measured target, and the relative angle change of the measured target is calculated.

[0049] In this embodiment, four tilt angle sensors are included, which are installed on the surface of the measured target and the key parts affecting the attitude;

[0050] The acquisition control device is used to power the tilt angle sensor under the condition of 220V / 50Hz power supply, and to manage the communication of the tilt angle sensor, and to convert the serial communication into Ethernet communication;

[0051] The upper computer is used for human-computer interaction, and cooperates with the rotation control system of the measured target to measure, store and display the motion of the measured target; and

[0052] The test cable is used for connecting the acquisition control device and the plurality of tilt angle sensors.

[0053] As a preferred embodiment, the tilt angle sensor is used to measure the attitude angle of the measured target. The tilt angle sensor is a MEMS tilt angle sensor, a single-axis axis angle sensor digital signal output, which includes a high-precision MEMS accelerometer and a high-resolution differential digital-to-analog converter, with built-in automatic compensation and filtering algorithm, effectively eliminating the error caused by installation. After compensation processing, the measurement range of the measurement axis is within 50°, the measurement range of the measurement axis is ±40°, the measurement accuracy can reach 0.1°, and the technical indicators include: the measurement axis is single-axis output; the measurement accuracy is 0.01°; the resolution is 0.001°; the range is ±40°; the power supply voltage is 9V~35V; the communication mode adopts RS-485; the working temperature range is-40℃~+85℃.

[0054] Referring to Figure 3, as a preferred embodiment, the acquisition control device is used for adapting 220V / 50Hz power supply conditions, and the communication management of the tilt sensor is converted into Ethernet communication. The acquisition control device is composed of a power module, a gateway, a splitter, a box, a switch, a front panel, a rear panel and an upper cover plate. The power module is used for converting 220V / 50Hz power supply into 12V power supply, and respectively supplying power to the gateway and the tilt sensor; the gateway is used for converting RS485 communication into Ethernet communication; the splitter is used for integrating multiple signals and power supply; the front panel of the box is provided with a switch for powering on the whole system; the rear panel is provided with a plurality of connectors for external power supply, tilt sensor power supply, communication and communication with the upper computer.

[0055] As a preferred embodiment, the plurality of connectors includes:

[0056] The socket network port connector is used for communication with the upper computer;

[0057] The 5-core metal socket is used for communication with the tilt sensor;

[0058] The power supply line is used for external power supply and tilt sensor power supply.

[0059] As a preferred embodiment, the power module is a 220V / 50Hz AC to DC power module, the power input of the power module is AC 220V / 50Hz, the power output is DC 12V / 10A, the protection form is overcurrent protection, overvoltage protection and overtemperature protection, the working temperature range is-20℃~60℃, and the storage temperature range is-40℃~85℃.

[0060] As a preferred embodiment, the gateway is an RS485 to Ethernet module, which can realize communication forwarding of up to not more than 255 RS485 nodes by using RS485 bus mode. The communication switching module includes: supporting RS232, RS422 and RS485 protocols; supporting UDP protocol; power supply voltage range is 9V~35V; working temperature range is-20℃~60℃; storage temperature range is-40℃~85℃.

[0061] As a preferred embodiment, the upper computer is connected with the gateway through Ethernet, and the transmission protocol adopts UDP transmission. The upper computer software module is divided as shown in Figure 4 The upper computer software is divided into three modules: device list module, test operation module and record query module. The device list module is used for updating and maintaining device information; the test operation module is divided into measurement site selection submodule, device initialization submodule, installation position determination submodule, start calibration submodule, zero value acquisition submodule, start / stop measurement submodule and reset submodule according to the test process; the record query module is used for querying and exporting measurement data.

[0062] As a preferred embodiment, the host computer software process is as follows: Figure 5 As shown. Devices can be modified through the device list module, and viewed and exported through the record query module. Select the measurement location and press the initialization button to initiate a power-on handshake. If all handshake results are complete, an anomaly check is performed. If no anomalies are found, a pop-up window will prompt for confirmation to continue. If continued, power-on initialization will proceed; otherwise, return to the initialization button. If an anomaly occurs during the handshake, a timeout mechanism will be initiated at intervals. An anomaly will be flagged and the system will return to the initialization button; otherwise, the power-on handshake will resume. After successful initialization, the operating condition will be selected and the location determined. The calibration method (no calibration, last calibration, or calibration) will be selected based on the sample measurement results. A calibration command will be sent based on the selected calibration method. If calibration is successful, a zero value will be returned and measurement will begin; if calibration fails, recalibration is required. After returning to the zero value, measurement will begin. Continuous or single-step measurement can be selected. For continuous measurement, manual termination and reset are required; for single-step measurement, measurement will automatically terminate.

[0063] Measurement principle:

[0064] 1. Operation functions, operating conditions selection, and calibration methods of the tilt sensor.

[0065] (1) Interface initial logic: When the system is turned on, the sensor initialization content of the default measurement part is automatically performed. When any operation other than initialization or reset is performed on the sensor, the measurement part and initialization function are prohibited.

[0066] (2) Time display: Displays the current time.

[0067] (3) Measurement area: This embodiment is specifically divided into two parts: the surface of the target being measured and the key parts of the target being measured to change attitude.

[0068] When the target surface is selected, the working condition selection box changes to target surface horizontal or target surface vertical.

[0069] When the key part of the target's attitude change is selected, the working condition selection box changes to either "key part of the target's attitude change is horizontal" or "key part of the target's attitude change is vertical".

[0070] Initialization: The system will automatically perform initialization when it starts up or when the measurement part is changed. This means that if an initialization error occurs, manual initialization will be performed after reconnecting or maintaining the equipment, and the sensor will be initialized before the next measurement.

[0071] Working condition: select the working condition of the measurement site.

[0072] Position determination: send two commands to the tilt sensor, first configure the working condition command, and second determine the position and return the result.

[0073] Start calibration: first select the calibration method, then send the start error calibration, three calibration collection commands to the tilt sensor in sequence, and query the calibration result.

[0074] Zero value: get and display the zero value of the current measurement content.

[0075] Single / continuous: select the measurement mode, single means take one value, continuous means take values continuously at a frequency of 20Hz.

[0076] Start measurement: send the start collection command to the tilt sensor, get the current value of the measurement content collection, calculate the angle, and display the calculated angle value. Select single mode: change to

measurement in progress

start measurement

end measurement

start measurement

[0077] Reset: reset the sensor.

[0078] Device list: enter the device list interface.

[0079] Record list: enter the record list interface.

[0080] 2、Device list

[0081] Display device name, label, measurement type, calibration method, calibration parameters, and other basic information, and can modify data.

[0082] Modify: select a data in the list to modify data, click to enter the modification interface.

[0083] 3、Device modification

[0084] Modify the name, id, and label of the tilt sensor.

[0085] 4、Record list

[0086] Display the test history record of the host computer, and support excel record export function

[0087] 5、Technical index analysis and design

[0088] Combine the actual test working condition of the device, analyze the measurement performance under different angle measurement environments, and the situation is as follows.

[0089] (1) The first kind of working condition of the measured target surface (the carrier is vertically placed)

[0090] 1) Angle calculation

[0091] The Z-axis is used as the measurement axis output , and the Z-axis is raised as positive and lowered as negative around the X-axis. The initial pitch angle before starting measurement is , and the output pitch angle after rotation is . The output angle change of the measured target surface is :

[0092]

[0093] The Z-axis accelerometer output has the following relationship with the gravitational acceleration g:

[0094]

[0095] From which the information can be solved:

[0096]

[0097] 2) Error analysis

[0098] During the installation of the tilt sensor, there will be installation errors in three directions due to machining, installation, and other operations, i.e., the X-axis and the installation end surface error , the Y-axis and the installation end surface installation error , and the heading installation error around the Z-axis . Since the measured target surface angle change is measured, the error source is the directional installation error, and the directional installation error angle is assumed to be 2° at most. The measured target surface swing range is [-32°, 32°], so the maximum measurement error occurs at the boundary. Considering a certain margin, it is assumed that the measured target surface changes by 40°, and the angle error value is as follows:

[0099]

[0100] Taking into account, the tilt sensor itself measures the angle error of 0.01° at most, and when the measured target surface changes by 40°, the maximum measured target surface measurement error value is about 0.04°, which meets the index requirements.

[0101] (2) The second kind of working condition of the measured target surface (the carrier is horizontally placed)

[0102] 1) Angle calculation

[0103] The working condition when the carrier is horizontally placed can be assumed that the tilt sensor is first rotated around the Y-axis angle, i.e. the angle of rotation of the measured target surface around the X-axis angle, i.e. the angle of rotation of the measured target surface around the Y-axis The change of the angle is the change of the angle of rotation of the measured target surface. The rotation matrix relationship is as follows:

[0104]

[0105] Suppose the pitch angle measured by the tilt sensor in the geodetic coordinate system is , the roll angle is , then

[0106]

[0107] 2) Error analysis

[0108] During the installation of the tilt sensor, there will be installation errors in three directions due to machining, installation and other operations, i.e. the error of the X-axis and the installation end face , the installation error of the Y-axis and the installation end face , and the heading installation error of rotation around the Z-axis . Since the change of the angle of the measured target surface is measured, the error source is the directional installation error, and suppose the maximum directional installation error angle is 2°, the swing range of the measured target surface is [-32°, 32°], so the maximum measurement error occurs at the boundary, and considering a certain margin, suppose the measured target surface is rolled by 45°, and the measured target surface is rotated by a maximum of 40°, i.e. , .

[0109] When , , the calculated pitch angle is , .

[0110] When the maximum directional installation error is 2°, the actual pitch angle measured at the pitch angle is , and considering the measurement error of the tilt sensor of 0.01°, the pitch angle is , , and the maximum error value is .

[0111] When the maximum directional installation error is 2°, the actual pitch angle measured at the roll angle is , and considering the measurement error of the tilt sensor of 0.01°, the pitch angle is , , and the maximum error value is .

[0112] Suppose the pitch and roll measurement errors are all at the maximum value, i.e. , , the calculated value is , . Therefore, when the measured target surface rotates 40°, the maximum error value is .

[0113] (3) The first working condition of the key part of the measured target attitude change (the carrier is vertically placed)

[0114] Through the installation design of the tooling, the tilt sensor can be ensured to be located on the swing axis of the key part of the measured target attitude change, and the slope design on the tooling can ensure the horizontal installation of the sensor. Therefore, the measurement principle in this measurement working condition is similar to the first working condition of the measured target attitude surface (the carrier is vertically placed), and the measurement accuracy can meet the measurement requirement of 0.1°.

[0115] (2) The second working condition of the key part of the measured target attitude change (the carrier is horizontally placed)

[0116] Through the installation design of the tooling, the tilt sensor can be ensured to be located on the pitch swing axis of the key part of the measured target attitude change, and the slope design on the tooling can ensure the horizontal installation of the sensor. Through the adjustment of the placement posture of the key part of the measured target attitude change, the swing axis can be placed at an angle of 45° with the horizontal plane. Therefore, the measurement principle in this measurement working condition is similar to the second working condition of the measured target attitude surface (the carrier is horizontally placed), and the measurement accuracy can meet the measurement requirement of 0.1°.

[0117] The application also provides a memory which stores a plurality of instructions for implementing the method of embodiment one.

[0118] As shown in Figure 6 , the application also provides an electronic device which comprises a processor 301 and a memory 302 connected with the processor 301, and the memory 302 stores a plurality of instructions which can be loaded and executed by the processor to enable the processor to perform the measurement method corresponding to the sensor of embodiment one.

[0119] Although the preferred embodiments of the application have been described, those skilled in the art can make additional changes and modifications to the embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including all the preferred embodiments and all the changes and modifications falling within the scope of the application. Obviously, those skilled in the art can make various modifications and variations to the application without departing from the spirit and scope of the application. Thus, if these modifications and variations of the application fall within the scope of the claims of the application and their equivalent technologies, the application also intends to include these modifications and variations.

Claims

1. An angle measurement system based on sample measurements, characterized by, The application relates to an angle measurement for a rotating measured target, wherein a rotation control system is arranged on the measured target, and the system comprises: A plurality of inclination sensors (1) and mounting tools, wherein the inclination sensors are N in number, are respectively arranged at N different positions of the measured target, N-1 sample measurement values are obtained, and the angle measurement results of the N-1 positions are taken as calibration samples to obtain the last angle measurement value; A collection control device (2) is used for adapting a first power supply condition to supply power to the inclination sensors, performing communication management on the inclination sensors, and converting serial communication into Ethernet communication; An upper computer (3) is used for man-machine interaction, and the movement of the measured target is measured, stored and displayed in cooperation with the rotation control system of the measured target; and A test cable is used for connecting the collection control device (2) and the plurality of inclination sensors (1); The inclination sensor measures the attitude information of the measured target relative to the geodetic coordinate system based on the gravity measurement principle, projects the attitude information in the geodetic coordinate system onto the surface of the measured target, calculates the relative angle change of the measured target, measures the gravity component by using an accelerometer, and thus the included angle between the measurement axis and the gravity is obtained; the direction of the gravity acceleration g is always vertically downward; when the measurement axis is horizontal, the gravity component measured by the accelerometer is zero; when the accelerometer is vertically upward, the measurement value is equal to the gravity; and when the measurement axis has an inclined included angle with the horizontal plane, the accelerometer measures the gravity component in the direction. The X-axis accelerometer output has the following relationship with the gravity acceleration g: （1）； In formula (1), is the acceleration information of the X-axis accelerometer output, g is the acceleration value with reference to gravity, is the sensor tilt angle, that is, the tilt angle of the measured target; Therefore, the angle value information can be solved: （2）； On the basis of measuring the attitude angle by the inclination sensor, adaptive improvement is carried out, the attitude information in the geodetic coordinate system is projected onto the surface of the measured target, and the relative angle change of the measured target is calculated.

2. An angle measurement system based on sample measurement according to claim 1, characterized in that, The system comprises four inclination sensors which are arranged on the surface of the measured target and the key positions influencing the attitude.

3. A sample measurement based angle measurement system according to claim 1, characterized in that, The inclination sensor (1) is a MEMS inclination sensor.

4. An angle measurement system based on sample measurement according to claim 1, characterized in that, The first power supply condition is a 220V / 50Hz power supply condition, and the collection control device is composed of a power module (21), a gateway (22), a line splitter (23), a box body (24), a switch (25), a front panel (26), a rear panel (27) and an upper cover plate (28); the power module (21) is used for converting the 220V / 50Hz power supply into a 12V power supply and supplying power to the gateway and the inclination sensor respectively; the gateway (22) is used for converting RS485 communication into Ethernet communication; the line splitter (23) is used for integrating multiple signals and power supply; the switch (25) is arranged on the front panel (26) of the box body and is used for powering on the whole system; a plurality of connectors are arranged on the rear panel (27) and are respectively used for external power supply, power supply and communication of the inclination sensor and communication with the upper computer.

5. An angle measurement system based on sample measurement according to claim 4, characterized in that, The plurality of connectors comprise: A socket network port connector (271) used for communication with the upper computer (3); A 5-core metal socket (272) used for communication with the inclination sensor (1); Power supply line (273) for external power supply and power supply for the tilt sensor (1).

6. An angle measurement system based on sample measurement according to claim 4, characterized in that, The power module is a 220V / 50Hz AC-DC power module.

7. An angle measurement system based on sample measurement according to claim 6, characterized in that, The gateway (22) is an RS485-to-Ethernet module, which can realize communication forwarding of up to 255 RS485 nodes by using RS485 bus mode.

8. A sample measurement based angle measurement system as claimed in claim 4, characterized in that, The host computer (3) is connected with the gateway (22) through Ethernet, and the transmission protocol adopts UDP transmission; the host computer software is divided into three modules, namely, a device list module, a test operation module and a record query module; the device list module is used for updating and maintaining device information; The test operation module is divided into a measurement site selection submodule, a device initialization submodule, an installation position determination submodule, a start calibration submodule, a zero value acquisition submodule, a start / stop measurement submodule and a reset submodule according to a test flow; The record query module is used for querying and exporting measurement data.

9. An angle measurement system based on sample measurement according to claim 8, characterized in that, The host computer software flow includes: modifying the device through the device list module; viewing and exporting the list through the record query module; during testing, selecting the measurement site and pressing the initialization button at the same time, implementing the power-on handshake, if the handshake result is completed, detecting whether there is an exception, if there is no exception, confirming whether to continue through the pop-up form, if continuing, starting the initialization, if not continuing, returning to the initialization button; if the handshake result is abnormal, starting the timeout mechanism according to the interval time, performing the abnormal identification under the timeout condition and returning to the initialization button, and returning to the power-on handshake under the non-timeout condition; after determining that the power-on initialization is completed, selecting the working condition and performing the position determination, selecting the calibration mode according to the sample measurement result, the calibration mode including no calibration, last calibration or calibration; sending the calibration command based on the selected calibration mode, if the calibration is successful, returning the zero value and starting the measurement, if the calibration fails, recalibrating; after determining the returned zero value, starting the measurement, selecting the continuous or single-step measurement mode, for the continuous measurement mode, manually ending the measurement and resetting, for the single-step measurement mode, automatically ending the measurement.

Images