Neutron diffraction stress measurement apparatus and method based on spatial coordinate measurement

Abstract

The application provides a neutron diffraction stress measurement device and method based on spatial coordinate measurement, comprising: an autonomous navigation trolley, a posture adjustment system, a spatial measurement sensor, a neutron detector, a sample table and a main controller; the posture adjustment system is fixedly installed on the autonomous navigation trolley, the neutron detector is detachably installed on the posture adjustment system, the autonomous navigation trolley is used for carrying the neutron detector and the posture adjustment system to move to a position near a specified position in a measurement space; the spatial measurement sensor is used for measuring the actual position and posture of the neutron detector in the measurement space and sending measurement data to the main controller; the main controller is used for sending motion instructions, receiving measurement data, performing coordinate transformation operation and kinematics inverse solution operation and outputting control signals. The application realizes accurate positioning of the neutron detector in the neutron measurement space by combining the autonomous navigation trolley, the posture adjustment system and the spatial measurement system, and completes the neutron diffraction stress measurement task.

Description

Technical Field

[0001] This invention relates to the field of neutron diffraction stress measurement technology, and more specifically, to a neutron diffraction stress measurement device and method based on spatial coordinate measurement. Background Technology

[0002] Neutron diffraction stress measurement technology is a key means of non-destructive testing of internal stress in materials. It is widely used in fields such as machinery manufacturing, aerospace, and nuclear energy equipment. By analyzing the diffraction characteristics of neutron beams, residual stress or working stress in materials can be inverted, which is crucial for evaluating the safety of components and the rationality of processes.

[0003] Existing neutron diffraction stress measurement devices mostly adopt a "fixed turntable + linkage mechanism" architecture, fixing the neutron detector to the turntable and adjusting its position through linkage transmission. This has obvious technical defects: First, the error accumulation is serious. Errors from multiple aspects such as turntable manufacturing deviation, linkage machining error, and assembly gap are superimposed, resulting in insufficient detector positioning accuracy and making it difficult to meet the requirements of high-precision measurement. Second, the movement flexibility is poor. The rigid constraint of the linkage restricts the detector's movement trajectory, making it unable to adapt to the measurement of large-sized samples, and the limited rotation angle around the sample easily creates measurement blind spots. Third, the attitude adjustment capability is weak, only achieving coarse adjustment of 2-3 degrees of freedom, which cannot finely compensate for sample clamping deviations or match specific diffraction angles, affecting signal reception efficiency.

[0004] The aforementioned shortcomings limit the measurement accuracy and application scenario expansion, making it difficult to meet the needs of complex samples and high-precision detection. There is an urgent need to improve the device architecture to overcome the technical bottleneck. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the purpose of this invention is to provide a neutron diffraction stress measurement device and method based on spatial coordinate measurement.

[0006] A neutron diffraction stress measurement device based on spatial coordinate measurement according to the present invention includes: an autonomous navigation vehicle, an attitude adjustment system, a spatial measurement sensor, a neutron detector, a sample stage, and a main controller;

[0007] The attitude adjustment system is fixedly installed on the autonomous navigation vehicle, and the neutron detector is detachably installed on the attitude adjustment system. The autonomous navigation vehicle is used to carry the neutron detector and the attitude adjustment system to a designated location within the measurement space.

[0008] The space measurement sensor is used to measure the actual position and attitude of the neutron detector in the measurement space and send the measurement data to the main controller;

[0009] The main controller is electrically connected with the autonomous navigation trolley, the attitude adjustment system and the space measurement sensor respectively, and is used for sending motion instructions, receiving measurement data, performing coordinate transformation operation and kinematics inverse solution operation, and outputting control signals.

[0010] The sample table is arranged in the measurement range of the neutron detector, and is used for carrying the measured sample and adjusting the position and attitude of the sample.

[0011] Preferably, the attitude adjustment system is a precise six-degree-of-freedom parallel mechanism, which is used for adjusting the six-degree-of-freedom position and attitude of the neutron detector to compensate for the motion error of the autonomous navigation trolley.

[0012] Preferably, the space measurement sensor is a laser tracker or a machine vision sensor, which is used for outputting the three-dimensional position and attitude data of the neutron detector in the measurement space.

[0013] Preferably, the probe motion mechanism is further arranged, which is connected with the space measurement sensor and is used for driving the space measurement sensor to adjust the spatial position.

[0014] Preferably, the detector controller is further arranged, which is electrically connected with the neutron detector and is used for controlling the working state of the neutron detector and recording the measurement data.

[0015] The detector controller receives the instructions of the main controller, controls the neutron detector to open / close the diffraction neutron beam measurement function, and records the measured neutron diffraction data in real time and feeds back to the main controller.

[0016] According to the present application, a neutron diffraction stress measurement method based on space coordinate measurement is provided, which comprises the following steps:

[0017] In step S1, the main controller obtains the target measurement position of the neutron detector, sends motion instructions to the autonomous navigation trolley, and the autonomous navigation trolley carries the neutron detector and the attitude adjustment system to move to the vicinity of the target measurement position according to the instructions.

[0018] In step S2, the main controller sends adjustment instructions to the probe motion mechanism synchronously, and the probe motion mechanism drives the space measurement sensor to move to the measurement station corresponding to the target measurement position.

[0019] In step S3, the space measurement sensor measures the position and attitude of the neutron detector, and sends the measured original data to the main controller.

[0020] Step S4: the main controller performs coordinate transformation operation on the original data, and converts the actual position and posture data of the neutron detector in the coordinate system of the spectrometer into the actual position and posture data of the neutron detector in the coordinate system of the spectrometer;

[0021] Step S5: the main controller calculates the deviation vector between the target measurement position and the actual position and posture, and performs kinematic inverse solution operation according to the deviation vector to obtain the joint space compensation amount for compensating the position and posture error;

[0022] Step S6: the main controller sends a control signal to the posture adjustment system according to the joint space compensation amount, and the posture adjustment system drives the neutron detector to move to complete the position and posture error compensation;

[0023] Step S7: if the actual position and posture of the neutron detector meets the measurement requirement, the main controller sends a measurement instruction to the detector controller, and the detector controller controls the neutron detector to start the measurement function to complete the neutron diffraction stress measurement of the current station and record the measurement data.

[0024] Preferably, the kinematic inverse solution operation in step S5 is a motion control algorithm for the posture adjustment system, which is used to calculate the displacement amount of each axis of the precise six-degree-of-freedom parallel mechanism in the joint space according to the deviation vector, so as to realize precise compensation of the six degrees of freedom of the neutron detector.

[0025] Preferably, the measurement accuracy of the space measurement sensor in step S3 is not less than 0.1 mm, and the three-dimensional coordinate and posture angle data of the neutron detector are output in real time.

[0026] Preferably, the method for adjusting the position of the space measurement sensor by the probe motion mechanism in step S2 comprises:

[0027] The adjustment target is no obstruction and straight linearity of the measurement path, so as to ensure that there is no obstacle between the space measurement sensor and the neutron detector to interfere with the measurement signal.

[0028] Compared with the prior art, the present application has the following beneficial effects:

[0029] 1. The present application directly measures the position and posture of the neutron detector in space through the space measurement sensor, solves the indirect measurement of the traditional neutron diffraction stress spectrometer turntable and the spectrometer structure of the connecting rod, avoids the accumulation of manufacturing errors, assembly errors and motion errors, and improves the system accuracy;

[0030] 2. The present application transports the neutron detector by the autonomous navigation trolley, and the neutron detector can run arbitrarily in the measurement space without being constrained by the detector table and the connecting rod, can automatically adjust the distance between the detector and the sample table, and the detector can rotate at a larger angle around the sample table without being limited by the mechanical structure of the connecting rod.

[0031] 3、The application can accurately adjust the position and posture of the neutron detector in six degrees of freedom in space through the posture adjustment system. The traditional neutron diffraction stress spectrometer is fixed and cannot be adjusted in multiple degrees of freedom directions, and completely depends on the installation accuracy and the motion accuracy of the turntable. BRIEF DESCRIPTION OF DRAWINGS

[0032] Other features, objects, and advantages of the application will become more apparent from the following detailed description of non-limiting embodiments, when read in conjunction with the accompanying drawings:

[0033] Figure 1 A structure schematic diagram of the neutron diffraction stress measurement device based on spatial coordinate measurement in the application;

[0034] Figure 2 A flowchart of the neutron diffraction stress measurement method based on spatial coordinate measurement in the application.

[0035] BRIEF DESCRIPTION OF DRAWINGS

[0036] DETAILED DESCRIPTION

[0037] The application will be described in detail below with specific embodiments. The following embodiments will help those skilled in the art to further understand the application, but do not limit the application in any form. It should be pointed out that those skilled in the art can make several changes and improvements without departing from the concept of the application. These all belong to the protection scope of the application.

[0038] The application discloses a neutron diffraction stress measurement device and method based on spatial coordinate measurement, referring to Figure 1 and Figure 2 As shown, by combining the self-navigation trolley 1, the posture adjustment system 2 and the spatial measurement system, the accurate positioning of the neutron detector 3 in the neutron measurement space is realized, and the neutron diffraction stress measurement task is completed.

[0039] The neutron diffraction stress measurement device based on spatial coordinate measurement comprises a self-navigation trolley 1, a posture adjustment system 2, a spatial measurement sensor 4, a neutron detector 3, a sample table 5 and a main controller.

[0040] The spatial measurement sensor 4 has the function of precise coordinate measurement in a large space range, can be used for measuring the actual position and posture of the neutron detector 3 in the measurement space, is used for judging whether the neutron detector 3 reaches the specified position, and provides adjustment data for the subsequent adjustment mechanism. The spatial detector can be realized by using different spatial measurement sensors 4 such as laser trackers and machine vision.

[0041] The main controller obtains the actual position and posture of the neutron detector 3 in the working coordinate system of the spectrometer through coordinate transformation according to the data measured by the spatial measurement sensor 4. The coordinate transformation is a conversion algorithm of spatial coordinates, which is used to convert the results measured by the posture adjustment system 2 into the actual position and posture of the neutron detector 3 in the working coordinate system of the spectrometer.

[0042] The posture adjustment system 2 is installed on the autonomous navigation vehicle 1, and the neutron detector 3 is installed on the posture adjustment system 2. The autonomous navigation vehicle 1 can carry the neutron detector 3 to any position in the measurement space, and the posture adjustment system 2 can finely adjust the position and posture of the neutron detector 3 in a small area to compensate for the motion error of the autonomous navigation vehicle 1.

[0043] The posture adjustment system 2 can adopt a precise six-degree-of-freedom parallel mechanism to realize precise positioning in a local range. The inverse kinematics solution is a motion control algorithm for the six-degree-of-freedom parallel mechanism, which is used to calculate the displacement of each axis of the parallel mechanism in the joint space according to the target position of the neutron detector 3.

[0044] The probe movement mechanism is used to change the position of the spatial measurement sensor 4. Because the measurement site environment is complex, the position of the spatial measurement sensor 4 is usually changed to avoid the shielding condition.

[0045] The sample table 5 is used to carry the measured sample 6 and adjust the position and posture of the sample 6.

[0046] The neutron detector 3 is used to measure the diffracted neutron beam. The detector controller is used to control the operation of the neutron detector 3 and record the measurement data.

[0047] The main controller controls the entire neutron diffraction stress measurement process.

[0048] The measurement method of the neutron diffraction stress measurement device based on spatial coordinate measurement will be further described below:

[0049] The neutron diffraction stress measurement method based on spatial coordinate measurement includes:

[0050] Step S1: After the main controller obtains the target measurement position of the neutron detector 3, the motion instruction is sent to the autonomous navigation vehicle 1, and the autonomous navigation vehicle 1 moves to the vicinity of the specified position according to the instruction.

[0051] Step S2: The main controller sends an instruction to control the probe movement mechanism to move the spatial measurement sensor 4 to a spatial measurement position corresponding to the target measurement position of the neutron detector 3.

[0052] Step S3: The spatial measurement sensor 4 measures the neutron detector 3 and sends the data to the main controller.

[0053] Step S4: After the main controller obtains the data measured by the spatial measurement sensor 4, the actual position and posture of the neutron detector 3 in the coordinate system of the spectrometer are obtained through coordinate transformation.

[0054] Step S5: The main controller calculates the deviation vector between the target position and the actual position of the neutron detector 3, and calculates the inverse kinematics of the six-degree-of-freedom parallel mechanism according to the deviation vector to obtain the joint space compensation amount of the six-degree-of-freedom parallel mechanism for compensating the position and posture error of the neutron detector 3.

[0055] Step S6: The main controller controls the movement of the six-degree-of-freedom parallel mechanism according to the above compensation amount to complete the position and posture error compensation of the neutron detector 3.

[0056] Step S7: When the position of the neutron detector 3 meets the measurement requirements, the measurement function can be started through the detector controller, the neutron measurement of the current step is completed, and the measurement data is recorded through the detector controller.

[0057] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0058] The specific embodiments of the present application have been described above. It should be understood that the present application is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essential content of the present application. In the case of no conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A neutron diffraction stress measurement device based on spatial coordinate measurement, characterized in that, include: The autonomous navigation vehicle (1), attitude adjustment system (2), space measurement sensor (4), neutron detector (3), sample stage (5) and main controller; The attitude adjustment system (2) is fixedly installed on the autonomous navigation vehicle (1), and the neutron detector (3) is detachably installed on the attitude adjustment system (2). The autonomous navigation vehicle (1) is used to carry the neutron detector (3) and the attitude adjustment system (2) to a designated location in the measurement space. The space measurement sensor (4) is used to measure the actual position and attitude of the neutron detector (3) in the measurement space and send the measurement data to the main controller; The main controller is electrically connected to the autonomous navigation vehicle (1), the attitude adjustment system (2), and the space measurement sensor (4) respectively, and is used to send motion commands, receive measurement data, perform coordinate transformation operations and inverse kinematics operations, and output control signals. The sample stage (5) is located within the measurement range of the neutron detector (3) and is used to carry the sample (6) to be tested and adjust the position and orientation of the sample (6).

2. The neutron diffraction stress measurement device based on spatial coordinate measurement according to claim 1, characterized in that, The attitude adjustment system (2) is a precision six-degree-of-freedom parallel mechanism used to adjust the six-degree-of-freedom position and attitude of the neutron detector (3) to compensate for the motion error of the autonomous navigation vehicle (1).

3. The neutron diffraction stress measurement device based on spatial coordinate measurement according to claim 1, characterized in that, The space measurement sensor (4) is a laser tracker or a machine vision sensor, used to output the three-dimensional position and attitude data of the neutron detector (3) in the measurement space.

4. The neutron diffraction stress measurement device based on spatial coordinate measurement according to claim 2, characterized in that, It also includes a probe motion mechanism, which is connected to the space measurement sensor (4) and is used to drive the space measurement sensor (4) to adjust its spatial position.

5. The neutron diffraction stress measuring device based on spatial coordinate measurement according to claim 4, characterized in that, It also includes a detector controller, which is electrically connected to the neutron detector (3) and is used to control the working state of the neutron detector (3) and record measurement data; The detector controller receives instructions from the main controller to control the neutron detector (3) to turn on / off the diffraction neutron beam measurement function, and records the measured neutron diffraction data in real time and feeds it back to the main controller.

6. A neutron diffraction stress measurement method based on spatial coordinate measurement, characterized in that, The method applied to the neutron diffraction stress measurement device based on spatial coordinate measurement as described in claim 5 includes the following steps: Step S1: The main controller obtains the target measurement position of the neutron detector (3) and sends a motion command to the autonomous navigation vehicle (1). The autonomous navigation vehicle (1) moves to the vicinity of the target measurement position according to the command, carrying the neutron detector (3) and the attitude adjustment system (2). Step S2: The main controller synchronously sends an adjustment command to the probe motion mechanism, and the probe motion mechanism drives the spatial measurement sensor (4) to move to the measurement station corresponding to the target measurement position; Step S3: The space measurement sensor (4) measures the position and attitude of the neutron detector (3) and sends the raw data obtained from the measurement to the main controller; Step S4: The main controller performs coordinate transformation on the original data and converts it into the actual position and attitude data of the neutron detector (3) in the working coordinate system of the spectrometer; Step S5: The main controller calculates the deviation vector between the target measured position and the actual position and attitude, and performs inverse kinematics calculation based on the deviation vector to obtain the joint space compensation amount used to compensate for the position and attitude error; Step S6: The main controller sends a control signal to the attitude adjustment system (2) according to the joint space compensation amount, and the attitude adjustment system (2) drives the neutron detector (3) to move to complete the position and attitude error compensation; Step S7: If the actual position and attitude of the neutron detector (3) meet the measurement requirements, the main controller sends a measurement command to the detector controller, and the detector controller controls the neutron detector (3) to start the measurement function, complete the neutron diffraction stress measurement of the current station, and record the measurement data.

7. The neutron diffraction stress measurement method based on spatial coordinate measurement according to claim 6, characterized in that, The inverse kinematics operation in step S5 is a motion control algorithm for the attitude adjustment system (2), which is used to calculate the displacement required by each axis of the precision six-degree-of-freedom parallel mechanism in the joint space according to the deviation vector, so as to realize the precise compensation of the six degrees of freedom of the neutron detector (3).

8. The neutron diffraction stress measurement method based on spatial coordinate measurement according to claim 6, characterized in that, The space measurement sensor (4) mentioned in step S3 has a measurement accuracy of not less than 0.1 mm and outputs the three-dimensional coordinates and attitude angle data of the neutron detector (3) in real time.

9. The neutron diffraction stress measurement method based on spatial coordinate measurement according to claim 6, characterized in that, The method for adjusting the position of the spatial measurement sensor (4) by the probe motion mechanism in step S2 includes: With the goal of ensuring unobstructed views and a straight measurement path, the measurement signal between the space measurement sensor (4) and the neutron detector (3) is ensured to be free from obstacles that could interfere with the measurement signal.

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