Method for correcting vibration condition of crawler running at constant speed on land

Abstract

The invention belongs to the technical field of vibration conditions, and particularly relates to a crawler land constant-speed driving vibration condition correction method, crawler land constant-speed driving vibration data is often regarded as a whole to be processed as a random vibration condition to guide design and examination of parts on a vehicle, and an induction result is usually in a narrow-band + wide-band random form. However, when the crawler runs at a constant speed on the land, the frequency domain characteristic of the vibration data is closer to the form of'sine + broadband random ', and the method is suitable for correction of such vibration conditions. The accuracy of the vibration condition is improved, vibration environment distortion caused by discomfort of the induction method is reduced, and over-test or under-test of the induction vibration test is avoided. According to the invention, the narrowband component in the vibration signal is regarded as the projection of the sinusoidal signal in the power spectral density, the center frequency and the relative amplitude of the narrowband signal are calculated and converted into the frequency and the amplitude of the sinusoidal signal, and the narrowband component is replaced by the sinusoidal component, so that more accurate vibration test conditions are obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of vibration conditions, and in particular relates to a method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land. Background Art

[0002] Vibration refers to the continuous load on a structure, the continuous application of force, displacement, velocity or acceleration that can cause continuous disturbance, and the continuous movement of the structure around a stable position over a continuous period of time. Since continuous vibration can cause damage and destruction to equipment, it is necessary to study the vibration environment in which the equipment is located and check its vibration resistance through a simulated environment. In order to guide equipment design and assess the vibration resistance of equipment, it is necessary to obtain the vibration data of the equipment, process the vibration data to obtain the typical vibration environment of the equipment, and formulate corresponding test conditions. It is crucial to make the formulated vibration conditions closer to the actual vibration environment that the equipment is subjected to.

[0003] Usually, the vibration environment of a tracked vehicle is considered to be a completely random vibration environment, so the vibration test conditions are usually summarized in the form of "narrowband + broadband random". For a tracked vehicle, the equipment installed on the tracked vehicle is an important carrier for the realization of the tracked vehicle's functions, and is related to the success or failure of the tracked vehicle's mission. However, due to the limited load of the tracked vehicle, the equipment on the vehicle is often required to be lightweight. Its structural strength is usually weaker than that of the chassis, and its vibration resistance is poor. Therefore, the vibration environment of tracked vehicles, especially the components on newly developed tracked vehicles, has attracted much attention.

[0004] Since the road conditions are random when the tracked vehicle is running, the vibration conditions of the tracked vehicle are usually summarized as a completely random vibration environment, which is summarized as a "narrowband + broadband random" vibration condition. However, when the tracked vehicle is running at a constant speed, its vibration excitation is closer to the "sine + broadband random" driving vibration, and the vibration energy is more concentrated in the frequency band. If the "narrowband + broadband random" form is used as the vibration condition, the equipment on the vehicle may be under-tested due to energy dispersion, or over-tested due to frequency broadening and interference with the natural frequency.

[0005] Using such unreasonable vibration conditions to guide the design or assessment of on-board equipment often leads to damage to the equipment during actual use, resulting in huge economic losses.

[0006] At present, there are almost no effective methods for correcting the vibration conditions of tracked vehicles driving at a constant speed on land at home and abroad. For such problems, more methods are adopted to improve the original test conditions and tighten the assessment equipment. Summary of the invention

[0007] 1. Technical issues to be resolved

[0008] The technical problem to be solved by the present invention is: how to obtain vibration conditions that are more in line with actual vibration characteristics through correction under the existing "narrowband + broadband random" vibration conditions. This method is required to make the corrected vibration adjustment closer to the actual vibration environment that the equipment is subjected to without changing the full-band vibration intensity of the original test conditions.

[0009] (II) Technical solution

[0010] In order to solve the above technical problems, the present invention provides a method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land, the method comprising the following steps:

[0011] Step 1: Calculate the relative amplitude of the narrowband component;

[0012] Step 2: Calculate the center frequency of the narrowband component;

[0013] Step 3: Calculate the relative RMS value of the narrowband component and convert it into the corresponding sinusoidal component amplitude;

[0014] Step 4: Replace the i-th narrowband component in the vibration condition with the center frequency of the i-th sinusoidal component and the amplitude of the i-th sinusoidal component respectively;

[0015] Through the above four steps, the correction of vibration conditions can be completed.

[0016] Wherein, the step 1: calculating the relative amplitude of the narrowband component;

[0017] The relative amplitude calculation process is as follows: f of each narrowband component is obtained through vibration test conditions. l (i) f h (i), A(i,f) and A of the broadband random component k (f); where f l (i) and f h (i) are the lower and upper frequency limits of the i-th narrowband component, respectively; A(i,f) is the amplitude of the i-th narrowband component, which is a function of the frequency f; f is the frequency in Hz;

[0018] Then, according to formula (1), the relative amplitude A of the i-th narrowband component is calculated: z (i,f);

[0019] A z (i,f)=A(i,f)-A k (f) i=1,2,…… (1)

[0020] Among them, f∈[f l (i),f h (i)]i=1,2,……。

[0021] Wherein, the step 2: calculating the center frequency of the narrowband component;

[0022] According to formula (2), calculate the center frequency f of the i-th narrowband component i ;

[0023]

[0024] Wherein, the step 3: calculates the relative RMS value of the narrowband component and converts it into the corresponding sinusoidal component amplitude:

[0025] According to formula (3), calculate the amplitude A of the i-th sinusoidal component sin (i);

[0026]

[0027] Wherein, in step 4, f i and A sin (i) are used as the frequency and amplitude of the i-th sinusoidal component and replace the i-th narrowband component in the vibration condition.

[0028] The method regards the narrowband component in the vibration condition as the projection of the sinusoidal component on the power spectrum density, calculates the center frequency and amplitude corresponding to the sinusoidal component, and replaces the narrowband component in the vibration condition with the calculated sinusoidal component to correct the vibration condition.

[0029] Among them, the method can be extended to the correction of "narrowband + broadband random" vibration conditions obtained by inducing other vibration signals derived from the superposition of stable sinusoidal excitation and random vibration.

[0030] The application of the method is not limited to the vibration conditions of the crawler vehicle traveling on land.

[0031] Among them, the method regards the narrowband component in the "narrowband + broadband random" vibration condition as the projection of the sinusoidal component on the power spectral density, calculates the amplitude-frequency response characteristic coefficient of the single-degree-of-freedom spring damping system, calculates the center frequency and RMS value of the narrowband signal and converts it into the frequency and amplitude of the sinusoidal signal, and obtains more accurate vibration test conditions by replacing the narrowband component with the sinusoidal component.

[0032] (III) Beneficial effects

[0033] Compared with the prior art, the technical solution of the present invention transforms the problem of extracting sinusoidal components from random signals into the problem of how to replace narrowband components with sinusoidal components equivalently. The narrowband components are regarded as the projections of the sinusoidal components on the power spectrum density, and the narrowband and broadband component information are used to calculate the frequency and amplitude of the sinusoidal components.

[0034] Finally, the present invention can correct the vibration conditions to be closer to the actual situation without changing the overall severity of the vibration conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a typical schematic diagram of the vibration condition curve of a tracked vehicle.

[0036] Figure 2-1 It is a schematic diagram of the power spectrum density of a tracked vehicle's constant speed running vibration data and the "narrowband + broadband random" vibration condition curve obtained by its induction.

[0037] Figure 2-2 It is a schematic diagram comparing the new vibration condition obtained after the vibration condition is corrected using this method with the original vibration condition. DETAILED DESCRIPTION

[0038] In order to make the purpose, content, and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below in conjunction with the accompanying drawings and examples.

[0039] In order to solve the above technical problems, the present invention provides a method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land, the method comprising the following steps:

[0040] Step 1: Calculate the relative amplitude of the narrowband component;

[0041] Step 2: Calculate the center frequency of the narrowband component;

[0042] Step 3: Calculate the relative RMS value of the narrowband component and convert it into the corresponding sinusoidal component amplitude;

[0043] Step 4: Replace the i-th narrowband component in the vibration condition with the center frequency of the i-th sinusoidal component and the amplitude of the i-th sinusoidal component respectively;

[0044] Through the above four steps, the correction of vibration conditions can be completed.

[0045] Wherein, the step 1: calculating the relative amplitude of the narrowband component;

[0046] The relative amplitude calculation process is as follows: f of each narrowband component is obtained through vibration test conditions. l (i) f h (i), A(i,f) and A of the broadband random component k (f); where f l (i) and f h (i) are the lower and upper frequency limits of the i-th narrowband component, respectively; A(i,f) is the amplitude of the i-th narrowband component, which is a function of the frequency f; f is the frequency in Hz;

[0047] Then, according to formula (1), the relative amplitude A of the i-th narrowband component is calculated: z (i,f);

[0048] A z (i,f)=A(i,f)-A k (f) i=1,2,…… (1)

[0049] Among them, f∈[f l (i),f h (i)]i=1,2,……。

[0050] Wherein, the step 2: calculating the center frequency of the narrowband component;

[0051] According to formula (2), calculate the center frequency f of the i-th narrowband component i ;

[0052]

[0053] Wherein, the step 3: calculates the relative RMS value of the narrowband component and converts it into the corresponding sinusoidal component amplitude:

[0054] According to formula (3), calculate the amplitude A of the i-th sinusoidal component sin (i);

[0055]

[0056] Wherein, in step 4, f i and A sin (i) are used as the frequency and amplitude of the i-th sinusoidal component and replace the i-th narrowband component in the vibration condition.

[0057] The method regards the narrowband component in the vibration condition as the projection of the sinusoidal component on the power spectrum density, calculates the center frequency and amplitude corresponding to the sinusoidal component, and replaces the narrowband component in the vibration condition with the calculated sinusoidal component to correct the vibration condition.

[0058] Among them, the method can be extended to the correction of "narrowband + broadband random" vibration conditions obtained by inducing other vibration signals derived from the superposition of stable sinusoidal excitation and random vibration.

[0059] The application of the method is not limited to the vibration conditions of the crawler vehicle traveling on land.

[0060] Among them, the method regards the narrowband component in the "narrowband + broadband random" vibration condition as the projection of the sinusoidal component on the power spectral density, calculates the amplitude-frequency response characteristic coefficient of the single-degree-of-freedom spring damping system, calculates the center frequency and RMS value of the narrowband signal and converts it into the frequency and amplitude of the sinusoidal signal, and obtains more accurate vibration test conditions by replacing the narrowband component with the sinusoidal component.

[0061] Example 1

[0062] In this embodiment, Figure 2-1 As shown in Table 2-1, it is the vibration condition spectrum obtained from the measured data in a certain tracked vehicle constant speed test, and its corresponding frequency and amplitude information. Figure 2-1 It can be seen that the inductive condition is in the form of "narrowband + broadband random", with a total of 4 narrow bands, but the vibration characteristics of the tracked vehicle when driving at a constant speed are closer to "sine + broadband random", so this vibration condition is not close enough to the actual situation. There is a risk of under-assessment or over-assessment when assessing the equipment on the vehicle based on this vibration condition, so it needs to be corrected. The correction process is as follows:

[0063] Step 1: Calculate the relative amplitude of the narrowband component;

[0064] From Table 2, we can obtain the f of each narrowband component. l (i) f h (i), A(i,f) and A of the broadband random component k (f) According to formula (1), the relative amplitude A of each narrowband component is calculated. z (i,f);

[0065] A z (i,f)=A(i,f)-A k (f) i=1,2,…… (1)

[0066] The calculation results are shown in Table 2-2.

[0067] Step 2: Calculate the center frequency of the narrowband component;

[0068] According to formula (2), calculate the center frequency f of each narrowband component i ;

[0069]

[0070] The calculation results are shown in Table 2-2.

[0071] Step 3: Based on the relative amplitude A of each narrowband z (i,f) calculate the corresponding sine component amplitude A sin (i)

[0072] According to formula (3), calculate the amplitude A of each sinusoidal component sin (i);

[0073]

[0074] The calculation results are shown in Table 2-2

[0075] Step 4: Take f i and A sin (i) are used as the frequency and amplitude of the i-th sinusoidal component and replace the i-th narrowband component in the vibration condition.

[0076] The schematic diagram of the vibration condition curve after replacement is as follows Figure 2-2 This completes the correction of vibration conditions.

[0077] Table 1 Figure 1 Frequency and amplitude information of typical tracked vehicle driving vibration conditions shown

[0078]

[0079] Table 2-1, Figure 2-1 Frequency and amplitude information for the “narrowband + broadband random” vibration conditions shown

[0080]

[0081] Table 2-2. Calculation values ​​and results of the vibration condition correction process using this method

[0082]

[0083] In summary, the present invention belongs to the technical field of vibration condition correction, and specifically relates to a method for correcting vibration conditions of a tracked vehicle traveling at a constant speed on land. In some cases, the vibration conditions of a tracked vehicle traveling at a constant speed are summarized as "narrowband + broadband random" forms, and this vibration cannot well characterize the real vibration environment to which the product is subjected. The method disclosed in the present invention is suitable for correcting such vibration conditions. The present invention mainly improves the accuracy of the vibration conditions, reduces the distortion of the vibration environment caused by the inappropriateness of the induction method, and avoids over-testing or under-testing of the induction vibration test. The present invention regards the narrowband component in the vibration signal as the projection of the sinusoidal signal on the power spectrum density, calculates the center frequency and relative amplitude of the narrowband signal and converts it into the frequency and amplitude of the sinusoidal signal, and obtains more accurate vibration test conditions by replacing the narrowband component with the sinusoidal component. The outstanding advantages of the present invention are that it has sufficient theoretical basis, does not require original vibration data, has a short calculation time, and the corrected data is accurate. Therefore, the present method has room for promotion and application.

[0084] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for correcting vibration conditions of a tracked vehicle traveling at a constant speed on land, characterized in that: The method comprises the following steps: Step 1: Calculate the relative amplitude of the narrowband component; Step 2: Calculate the center frequency of the narrowband component; Step 3: Calculate the relative RMS value of the narrowband component and convert it into the corresponding sinusoidal component amplitude; Step 4: Replace the i-th narrowband component in the vibration condition with the center frequency of the i-th sinusoidal component and the amplitude of the i-th sinusoidal component respectively; Through the above four steps, the correction of vibration conditions can be completed.

2. The method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land according to claim 1, characterized in that: The step 1: calculating the relative amplitude of the narrowband component; The relative amplitude calculation process is as follows: f of each narrowband component is obtained through vibration test conditions. l (i) f h (i), A(i,f) and A of the broadband random component k (f); where f l (i) and f h (i) are the lower and upper frequency limits of the i-th narrowband component, respectively; A(i,f) is the amplitude of the i-th narrowband component, which is a function of the frequency f; f is the frequency in Hz; Then, according to formula (1), the relative amplitude A of the i-th narrowband component is calculated: z (i,f); A z (i,f)=A(i,f)-A k (f) i=1,2,…… (1) Among them, f∈[f l (i),f h (i)]i = 1, 2, ….

3. The method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land according to claim 2, characterized in that: The step 2: calculating the center frequency of the narrowband component; According to formula (2), calculate the center frequency f of the i-th narrowband component i ; 4. The method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land according to claim 3, characterized in that: Step 3: Calculate the relative RMS value of the narrowband component and convert it into the corresponding sinusoidal component amplitude: According to formula (3), calculate the amplitude A of the i-th sinusoidal component sin (i); 5. The method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land according to claim 4, characterized in that: In step 4, f i and A sin (i) are used as the frequency and amplitude of the i-th sinusoidal component and replace the i-th narrowband component in the vibration condition.

6. The method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land according to claim 5, characterized in that: The method regards the narrowband component in the vibration condition as the projection of the sinusoidal component on the power spectrum density, calculates the center frequency and amplitude corresponding to the sinusoidal component, and replaces the narrowband component in the vibration condition with the calculated sinusoidal component to correct the vibration condition.

7. The method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land according to claim 5, characterized in that: The method can be extended to the correction of "narrowband + broadband random" vibration conditions obtained by inducing other vibration signals derived from the superposition of stable sinusoidal excitation and random vibration.

8. The method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land according to claim 5, characterized in that: The application of the method is not limited to the vibration conditions of tracked vehicles on land.

9. The method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land according to claim 5, characterized in that: The method regards the narrowband component in the "narrowband + broadband random" vibration condition as the projection of the sinusoidal component on the power spectrum density, calculates the amplitude-frequency response characteristic coefficient of the single-degree-of-freedom spring damping system, calculates the center frequency and RMS value of the narrowband signal and converts it into the frequency and amplitude of the sinusoidal signal, and obtains more accurate vibration test conditions by replacing the narrowband component with the sinusoidal component.

10. The method for correcting vibration conditions of a crawler vehicle traveling at a constant speed on land according to claim 5, characterized in that: The method transforms the problem of extracting sinusoidal components from random signals into the problem of how to replace narrowband components with sinusoidal components equivalently; by considering the narrowband components as the projections of the sinusoidal components on the power spectrum density and then using the narrowband and broadband component information, the frequency and amplitude of the sinusoidal components are calculated.

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