Contact detection method and device for weakly rigid thermal protection members

Abstract

The application provides a contact detection method and device for a weak-rigidity thermal protection component, and the application comprises the following steps: obtaining physical parameters and real-time motion data of a scanning probe through a data acquisition and parameter estimation module, combining an online rigidity estimation module, and estimating the environmental equivalent rigidity and the environmental position of a contact interface between the scanning probe and the weak-rigidity thermal protection component in real time; outputting expected impedance rigidity and damping coefficients that are adaptive to a contact state through a fuzzy reasoning decision module; constructing a real-time impedance model and solving expected acting force by using an impedance model solution module; and solving driving voltage and controlling the probe to output matched actual contact force by using an actuator driving control module, so that the force response is stable, the contact state is adaptively regulated and controlled, the component is prevented from being damaged due to deformation, and the detection precision is improved in the weak-rigidity component contact detection process.

Description

Technical Field

[0001] This invention relates to the field of testing technology, and in particular to a contact testing method and apparatus for weakly rigid thermal protection components. Background Technology

[0002] Thermal protection systems, as a core safety guarantee for hypersonic vehicles, are widely used in launch vehicles and reentry missions. With increasing flight Mach numbers, this field has developed into a complex collaborative system encompassing fiber-reinforced ceramic panels, aerogel core materials, and metal load-bearing structures. Specifically, weakly rigid components are fabricated through stitching, impregnation, and sintering processes, and their assembly and testing rely on adhesive quality assessment and surface matching verification, forming a key technological closed loop from material forming to final assembly and delivery.

[0003] However, in existing detection technologies, contact methods often lack environmental stiffness sensing and force control adaptive mechanisms, directly applying a constant contact force, which can easily lead to scratches or plastic deformation on the surface of weakly rigid components. While non-contact methods avoid physical contact, they are limited by optical window interference and the accuracy of inversion algorithms, making it difficult to accurately quantify the spatial location and geometric dimensions of minute debonding defects. This insufficient detection capability results in a lack of data support for process iteration, severely restricting the reliability assessment and maintenance efficiency of thermal protection systems. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] Therefore, the first objective of this invention is to provide a contact-based testing method for weakly rigid thermal protection components.

[0006] Another objective of this invention is to provide a contact-type detection device for weakly rigid thermal protection components.

[0007] The third objective of this invention is to provide a computer device.

[0008] A fourth objective of this invention is to provide a non-transitory computer-readable storage medium.

[0009] To achieve the above objectives, a first aspect of the present invention provides a contact-based testing method for weakly rigid thermal protection components, comprising:

[0010] S1, acquire the physical parameters of the scanning probe and the real-time motion data during the contact process, and perform joint online estimation of the environmental equivalent stiffness and environmental position of the contact interface between the scanning probe and the weakly rigid thermal protection component based on the nonlinear filtering algorithm; S2, input the environmental equivalent stiffness and the real-time motion data into the fuzzy inference controller, and dynamically output the desired impedance stiffness coefficient and desired damping coefficient that are adapted to the current contact state according to the preset fuzzy rule mapping relationship. S3. Based on the desired impedance stiffness coefficient, the desired damping coefficient, and the preset desired displacement trajectory, a real-time impedance model is constructed and the desired force required to maintain the ideal contact response is calculated. S4. Calculate the corresponding actuator drive voltage based on the desired force, and apply the drive voltage to the active scanning probe to control the scanning probe to output an actual contact force consistent with the desired force during the contact detection process.

[0011] In one embodiment of the present invention, S1 includes: Read the pre-stored design manual data to obtain the mass, damping coefficient and stiffness of the scanning probe, and collect the displacement, velocity and acceleration data at the current moment; Based on the aforementioned mass, damping coefficient, stiffness, and collected motion data, using the formula:

[0012] Calculate the contact force and approximate it as an equivalent spring model. ; Define a state vector that includes environmental stiffness and environmental position. Using the extended Kalman filter method, based on the data collected in the previous control cycle and the formula for predicting environmental stiffness:

[0013] The equivalent stiffness and location of the environment can be predicted online in real time.

[0014] In one embodiment of the present invention, the definition includes state vectors for environmental stiffness and environmental position. Using an extended Kalman filter method, based on data collected from the previous control cycle and formulas, the equivalent environmental stiffness and environmental position are predicted online in real time, including: based on Calculation of all information at any given time The prior estimate of the state at time step 1 is obtained, and the Kalman gain and observation residual at the current time step are calculated. The prior estimates, Kalman gain, and observation residuals are substituted into the formula for predicting environmental stiffness for iterative updates. The output is a state vector containing real-time updated environmental equivalent stiffness and environmental position, thereby achieving robust identification and high-precision modeling of external contact states.

[0015] In one embodiment of the present invention, S2 includes: The equivalent stiffness of the environment is divided into five levels: very soft, soft, medium, hard, and very hard. Triangular membership functions are constructed to describe the linguistic variable ranges of input and output. Based on the preset fuzzy rule mapping relationship, very soft is mapped to very low, soft is mapped to low, medium is mapped to medium, hard is mapped to high, and very hard is mapped to very high, so as to output the corresponding desired impedance stiffness coefficient. Based on the desired impedance stiffness coefficient and fixed damping ratio, using the formula The desired damping coefficient is calculated, where It is a fixed value.

[0016] In one embodiment of the present invention, S3 includes: Obtain the preset desired displacement trajectory and its corresponding first derivative. and second derivative; Substituting the desired impedance stiffness coefficient, the desired damping coefficient, the fixed value, and the desired displacement trajectory and its derivative into the formula: ; By performing the calculations of the formula, the desired force reflecting the ideal response of the probe to changes in the contact environment can be calculated.

[0017] In one embodiment of the present invention, S4 includes: The resistance, inductance, force constant, and back electromotive force constant of the voice coil motor are obtained, and the displacement and velocity of the scanning probe are acquired in real time. Calculate the rate of change of the desired force over time, and substitute the desired force, rate of change, and motor parameters into the formula: ; The driving voltage is obtained by solving the equation, and the driving voltage is applied to the actuator that drives the voice coil motor to achieve adaptive control of the contact force.

[0018] In one embodiment of the present invention, the step of solving for the driving voltage and applying the driving voltage to the actuator driving the voice coil motor to achieve adaptive control of the contact force includes: By adjusting the magnitude of the driving voltage, the range of the output contact force of the voice coil motor can be controlled; During the contact detection process, the driving voltage is dynamically adjusted in real time based on sensor feedback to switch the rigidity and flexibility of the probe, preventing scratches on the weak rigid thermal protection components due to excessive contact force or measurement errors due to insufficient contact force.

[0019] To achieve the above objectives, a second aspect of the present invention provides a contact-type detection device for a weakly rigid thermal protection component, comprising: The present invention discloses a contact-type detection method and apparatus for weakly rigid thermal protection components. By sensing the environmental stiffness in real time and adaptively adjusting the contact force, it effectively avoids damage and deformation of the weakly rigid thermal protection components during the detection process. At the same time, it achieves high-precision measurement and automated detection at the micron level, significantly improving detection efficiency and result reliability.

[0020] To achieve the above objectives, a third aspect of this application provides a computer device comprising a processor and a memory; wherein the processor runs a program corresponding to the executable program code stored in the memory to implement a contact detection method for a weakly rigid thermal protection component as described in the first aspect embodiment.

[0021] To achieve the above objectives, a fourth aspect of this application provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a contact detection method for a weakly rigid thermal protection component as described in the first aspect embodiment.

[0022] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0023] Figure 1 This is a flowchart of a contact-type testing method for a weakly rigid thermal protection component according to an embodiment of the present invention; Figure 2 This is a flowchart of a contact detection algorithm for a weakly rigid thermal protection component according to an embodiment of the present invention. Figure 3 These are three views of the active scanning probe structure according to an embodiment of the present invention; Figure 4 This is a block diagram of the overall algorithm architecture according to an embodiment of the present invention; Figure 5 This is a structural diagram of a contact-type detection device for a weakly rigid thermal protection component according to an embodiment of the present invention; Figure 6 It is a computer device according to an embodiment of the present invention. Detailed Implementation

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0026] The following description, with reference to the accompanying drawings, describes a contact-type testing method and apparatus for weakly rigid thermal protection components according to an embodiment of the present invention.

[0027] Figure 1 This is a flowchart of a contact-type testing method for a weakly rigid thermal protection component according to an embodiment of the present invention, such as... Figure 1 As shown, it includes: S1, acquire the physical parameters of the scanning probe and the real-time motion data during the contact process, and perform joint online estimation of the environmental equivalent stiffness and environmental position of the contact interface between the scanning probe and the weakly rigid thermal protection component based on the nonlinear filtering algorithm; S2, input the environmental equivalent stiffness and the real-time motion data into the fuzzy inference controller, and dynamically output the desired impedance stiffness coefficient and desired damping coefficient that are adapted to the current contact state according to the preset fuzzy rule mapping relationship. S3. Based on the desired impedance stiffness coefficient, the desired damping coefficient, and the preset desired displacement trajectory, a real-time impedance model is constructed and the desired force required to maintain the ideal contact response is calculated. S4. Calculate the corresponding actuator drive voltage based on the desired force, and apply the drive voltage to the active scanning probe to control the scanning probe to output an actual contact force consistent with the desired force during the contact detection process.

[0028] The specific flow of the algorithm in this embodiment of the invention is as follows: Figure 2 As shown. This algorithm is based on an active force-controlled scanning probe driven by a voice coil motor, as shown in the figure. Figure 3 As shown, this probe can achieve active control of the three degrees of freedom (X, Y, and Z).

[0029] Furthermore, the overall architecture of the algorithm is shown in Figure 4. The algorithm consists of four modules. First, the controller, based on the original data (probe mass m, damping coefficient b, equivalent stiffness k) and the Extended Kalman Filter (EKF) method, estimates the equivalent environmental stiffness Ke during the contact process between the scanning probe and the object being measured in real time. Then, this stiffness estimation result is input to the fuzzy inference controller, which combines a set of fuzzy rules based on expert experience and system response characteristics to output appropriate impedance stiffness coefficients Kd and Bd. Based on the stiffness coefficients Kd and Bd, a real-time impedance model can be constructed, and the desired force Fr can be calculated to reflect the ideal response of the probe to changes in the contact environment. After calculating the desired force Fr, the driving voltage corresponding to the desired force is solved using the desired force as input and applied to the actuator to ensure that the actual output force is consistent with the desired force.

[0030] Furthermore, the above algorithm organically integrates environmental perception, adaptive parameter adjustment, impedance modeling, and force precision control to form a contact force control system with fast response, strong compliance, and high adaptability, which can effectively meet the dual requirements of variable environment and high-precision force feedback in the detection of weak rigid thermal protection components.

[0031] Furthermore, the specific analysis of the algorithm is as follows: Based on the online environmental stiffness estimation using the Extended Kalman Filter (EKF) method, according to the design manual, the mass m, damping coefficient b, and stiffness k of the scanning probe can be obtained. The contact force can then be expressed by the following formula:

[0032] Since the mass m, damping coefficient b, and stiffness k of the probe are all known, the contact force can be approximated as an equivalent spring model:

[0033] Where K_e represents environmental stiffness and x_e represents environmental position, a nonlinear filtering model for joint estimation of environmental stiffness and dynamic position is constructed using the Extended Kalman Filter (EKF) method. Define the state vector:

[0034] Based on the settings of the extended Kalman filter (EKF), the stiffness of the environment can be predicted online in real time using the data collected in the previous control cycle.

[0035] in The prior estimate is the state at time k based on all information at time k-1. The predicted value. The Kalman gain at the current moment. To observe the residuals.

[0036] Furthermore, the fuzzy inference controller takes the predicted environmental stiffness Ke from the previous step as input, outputs the desired stiffness coefficient Kd, and calculates the corresponding desired damping coefficient Bd using the following formula:

[0037] In the above formula, Md is a fixed value. According to the optimal response requirements of the second-order system, the fixed damping ratio ξ = 0.707 is set.

[0038] The environmental stiffness is divided into five levels: very soft (VS), soft (S), medium (M), hard (H), and very hard (VH). The desired output stiffness level is also divided into five corresponding levels: very low (VL), low (L), medium (M), and high (H). Very high (VH) corresponds to the ideal response requirements of the system in low, medium, and high stiffness environments, as shown in Table 1.

[0039] Table 1

[0040] By constructing triangular membership functions to describe the linguistic variable ranges of input and output, and sequentially completing inference processes such as fuzzification, rule matching, synthesis, and defuzzification, a continuous control quantity can be output, allowing for online dynamic adjustment of system parameters (desired stiffness coefficient Kd and desired damping coefficient Bd).

[0041] Furthermore, the impedance controller takes the parameters obtained in the previous step (desired stiffness coefficient Kd, desired damping coefficient Bd) and the desired displacement. Substitute into the following formula:

[0042] The desired force Fr can be calculated.

[0043] Furthermore, the voice coil motor force controller can calculate the driving voltage corresponding to the desired force Fr based on the driving formula of the voice coil motor. Using this as input, contact force control can be achieved in contact testing of weakly rigid thermal protection components: .

[0044] The embodiments of this invention also have the following technical effects: Self-sensing of environmental stiffness: Based on raw data, the algorithm continuously integrates historical estimates and current measurements during the contact process, dynamically tracking changes in environmental stiffness and position, thereby achieving robust identification and high-precision modeling of external contact states. Adaptive control of contact force: To adapt to diverse measurement needs under complex spatial poses and with weakly rigid thermal protection components of different materials and stiffnesses, the algorithm can freely adjust the contact force within the range of 0.001N to 1N by adjusting the driving voltage of the voice coil motor, and can dynamically adjust the contact force in real time during actual measurement by combining sensor feedback. This function helps to effectively prevent deformation of the measured workpiece, signal drift, or measurement errors caused by excessive or insufficient contact force, improving the overall accuracy and stability of the measurement. In addition, the contact stiffness of the probe should also have a certain degree of adjustability so as to switch between stiffness and flexibility characteristics according to the specific needs of the measurement task, thereby enhancing the system's adaptability to complex working conditions and improving the reliability and accuracy of surface contour measurement. High measurement accuracy and detection efficiency: The contact measurement scheme adopted by this algorithm has micron-level detection accuracy. Furthermore, this algorithm can be used in conjunction with a coordinate measuring machine or robotic arm to automate the inspection of weakly rigid thermal protection components, significantly improving inspection efficiency.

[0045] To achieve the above embodiments, such as Figure 5 As shown, this embodiment also provides a contact detection device 10 for weakly rigid thermal protection components, including: The data acquisition and parameter estimation module 100 is used to acquire the physical parameters of the scanning probe and the real-time motion data during the contact process. Based on the nonlinear filtering algorithm, the environmental equivalent stiffness and environmental position of the contact interface between the scanning probe and the weakly rigid thermal protection component are jointly estimated online. The fuzzy inference decision module 200 is used to input the environmental equivalent stiffness and the real-time motion data into the fuzzy inference controller, and dynamically output the desired impedance stiffness coefficient and desired damping coefficient that are adapted to the current contact state according to the preset fuzzy rule mapping relationship. The impedance model solution module 300 is used to construct a real-time impedance model and calculate the desired force required to maintain the ideal contact response based on the desired impedance stiffness coefficient, the desired damping coefficient and the preset desired displacement trajectory. The actuator drive control module 400 is used to calculate the corresponding actuator drive voltage according to the desired force, and apply the drive voltage to the active scanning probe to control the scanning probe to output an actual contact force consistent with the desired force during the contact detection process.

[0046] This invention discloses a contact-type testing device for weakly rigid thermal protection components. By sensing the environmental stiffness in real time and adaptively adjusting the contact force, it effectively avoids damage and deformation of the weakly rigid thermal protection components during the testing process. At the same time, it achieves high-precision measurement and automated testing at the micron level, significantly improving testing efficiency and result reliability.

[0047] To implement the methods of the above embodiments, the present invention also provides a computer device, such as... Figure 6 As shown, the computer device 600 includes a memory 601 and a processor 602; wherein, the processor 602 reads the executable program code stored in the memory 601 to run a program corresponding to the executable program code, so as to implement the various steps of the contact detection method for a weakly rigid thermal protection component described above.

[0048] To implement the above embodiments, this application also proposes a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements a contact detection method for a weakly rigid thermal protection component as described in the foregoing embodiments.

[0049] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0050] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

Claims

1. A contact-based testing method for weakly rigid thermal protection components, characterized in that, include: S1, acquire the physical parameters of the scanning probe and the real-time motion data during the contact process, and perform joint online estimation of the environmental equivalent stiffness and environmental position of the contact interface between the scanning probe and the weakly rigid thermal protection component based on the nonlinear filtering algorithm; S2, input the environmental equivalent stiffness and the real-time motion data into the fuzzy inference controller, and dynamically output the desired impedance stiffness coefficient and desired damping coefficient that are adapted to the current contact state according to the preset fuzzy rule mapping relationship. S3. Based on the desired impedance stiffness coefficient, the desired damping coefficient, and the preset desired displacement trajectory, a real-time impedance model is constructed and the desired force required to maintain the ideal contact response is calculated. S4. Calculate the corresponding actuator drive voltage based on the desired force, and apply the drive voltage to the active scanning probe to control the scanning probe to output an actual contact force consistent with the desired force during the contact detection process.

2. The method as described in claim 1, characterized in that, S1 includes: Read the pre-stored design manual data to obtain the mass, damping coefficient and stiffness of the scanning probe, and collect the displacement, velocity and acceleration data at the current moment; Based on the aforementioned mass, damping coefficient, stiffness, and collected motion data, using the formula: Calculate the contact force and approximate it as an equivalent spring model. ; Define a state vector that includes environmental stiffness and environmental position. Using the extended Kalman filter method, based on the data collected in the previous control cycle and the formula for predicting environmental stiffness: The equivalent stiffness and location of the environment can be predicted online in real time.

3. The method as described in claim 2, characterized in that, The definition includes state vectors for environmental stiffness and environmental location. Using the extended Kalman filter method, based on data and formulas collected from the previous control cycle, the equivalent environmental stiffness and environmental location are predicted online in real time, including: based on Calculation of all information at any given time The prior estimate of the state at time step 1 is obtained, and the Kalman gain and observation residual at the current time step are calculated. The prior estimates, Kalman gain, and observation residuals are substituted into the formula for predicting environmental stiffness for iterative updates. The output is a state vector containing real-time updated environmental equivalent stiffness and environmental position, thereby achieving robust identification and high-precision modeling of external contact states.

4. The method as described in claim 1, characterized in that, The S2 includes: The equivalent stiffness of the environment is divided into five levels: very soft, soft, medium, hard, and very hard. Triangular membership functions are constructed to describe the linguistic variable ranges of input and output. Based on the preset fuzzy rule mapping relationship, very soft is mapped to very low, soft is mapped to low, medium is mapped to medium, hard is mapped to high, and very hard is mapped to very high, so as to output the corresponding desired impedance stiffness coefficient. Based on the desired impedance stiffness coefficient and fixed damping ratio, using the formula The desired damping coefficient is calculated, where It is a fixed value.

5. The method as described in claim 1, characterized in that, The S3 includes: Obtain the preset desired displacement trajectory and its corresponding first derivative. and second derivative; Substituting the desired impedance stiffness coefficient, the desired damping coefficient, the fixed value, and the desired displacement trajectory and its derivative into the formula: ； By performing the calculations of the formula, the desired force reflecting the ideal response of the probe to changes in the contact environment can be determined.

6. The method as described in claim 1, characterized in that, The S4 includes: The resistance, inductance, force constant, and back electromotive force constant of the voice coil motor are obtained, and the displacement and velocity of the scanning probe are acquired in real time. Calculate the rate of change of the desired force over time, and substitute the desired force, rate of change, and motor parameters into the formula: ； The driving voltage is obtained by solving the problem and then applied to the actuator that drives the voice coil motor to achieve adaptive control of the contact force.

7. The method as described in claim 6, characterized in that, The process of solving for the driving voltage and applying it to the actuator driving the voice coil motor to achieve adaptive control of the contact force includes: By adjusting the magnitude of the driving voltage, the range of the output contact force of the voice coil motor can be controlled; During the contact detection process, the driving voltage is dynamically adjusted in real time based on sensor feedback to switch the rigidity and flexibility of the probe, preventing scratches on the weak rigid thermal protection components due to excessive contact force or measurement errors due to insufficient contact force.

8. A contact-type testing device for weakly rigid thermal protection components, characterized in that, include: The data acquisition and parameter estimation module is used to acquire the physical parameters of the scanning probe and the real-time motion data during the contact process. Based on the nonlinear filtering algorithm, the environmental equivalent stiffness and environmental position of the contact interface between the scanning probe and the weakly rigid thermal protection component are jointly estimated online. The fuzzy inference decision module is used to input the equivalent stiffness of the environment and the real-time motion data into the fuzzy inference controller, and dynamically output the desired impedance stiffness coefficient and desired damping coefficient that are adapted to the current contact state according to the preset fuzzy rule mapping relationship. The impedance model solution module is used to construct a real-time impedance model and calculate the desired force required to maintain the ideal contact response based on the desired impedance stiffness coefficient, the desired damping coefficient and the preset desired displacement trajectory. The actuator drive control module is used to calculate the corresponding actuator drive voltage according to the desired force, and apply the drive voltage to the active scanning probe to control the scanning probe to output an actual contact force consistent with the desired force during the contact detection process.

9. A computer device, characterized in that, Including processor and memory; The processor reads executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement a contact detection method for a weakly rigid thermal protection component as described in any one of claims 1-7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements a contact detection method for a weakly rigid thermal protection component as described in any one of claims 1-7.

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