Control method and device of road roller

Abstract

The invention discloses a control method and device of a road roller in the technical field of vibratory road roller control, and aims to solve the technical problems that an abnormal working state is difficult to judge and protective shutdown is difficult to realize in vibratory compaction operation. The method comprises the steps that a second-order system inherent frequency value between the road roller and a soil layer is obtained, and vibration compaction operation is stopped in response to the fact that the second-order system inherent frequency value reaches a first threshold value; the actual vibration frequency value of the road roller is obtained, and vibration compaction operation is stopped when the actual vibration frequency value is smaller than a second threshold value; the compaction degree value of the soil layer is obtained, and vibration compaction operation is stopped when the compaction degree value is larger than a third threshold value; the abnormal working state of the whole process of the vibration compaction operation of the road roller is judged, and the vibration compaction operation is protectively stopped, so that the road roller is prevented from excessively compacting a fully compacted soil layer, ineffective operation with uncontrollable quality is prevented, and the working efficiency of the road roller is improved. And during normal vibration compaction operation, the road roller is prevented from continuously vibrating and being damaged after driving into a compacted soil layer.

Description

Technical Field

[0001] The invention relates to a control method and device for a road roller, belonging to the technical field of vibratory road roller control. Background Art

[0002] Commonly used soil compaction degree detection and control methods, including sand filling method, load plate method, falling ball method, etc., usually can only give the compaction degree of the sampling point, rather than the compaction degree of the entire soil layer, and the above methods are all implemented after the vibration compaction operation. However, it is difficult for the roller to know the compaction state of the soil layer during the vibration compaction operation. It is possible that the soil layer cannot be fully vibrated and compacted, or it is possible to continue compacting on the fully compacted paving layer, resulting in the destruction of the compacted paving layer. Existing rollers are difficult to identify the abnormal state of the compaction operation during operation and take corresponding measures after stopping the work.

[0003] In summary, the existing control method for road rollers cannot effectively identify abnormal working conditions and prevent the rollers from operating in a protective manner during vibration compaction operations. Summary of the invention

[0004] The purpose of the present application is to overcome the deficiencies in the prior art and to provide a control method and device for a road roller that can identify abnormal working conditions during vibration compaction operations and perform protective shutdowns.

[0005] In order to achieve the above objectives, this application is implemented by adopting the following technical solutions: In a first aspect, the present application provides a control method for a road roller, comprising: Acquiring a second-order system natural frequency value between the roller and the soil layer, and stopping the vibration compaction operation in response to the second-order system natural frequency value reaching a first threshold; Acquiring an actual vibration frequency value of the roller, and stopping the vibration compaction operation in response to the actual vibration frequency value being less than a second threshold value; A compaction degree value of the soil layer is obtained, and in response to the compaction degree value being greater than a third threshold value, the vibration compaction operation is stopped.

[0006] In some embodiments of the first aspect, obtaining the second-order system natural frequency value between the roller and the soil layer includes: Acquire the vibration acceleration of the roller, and acquire acceleration data within a set time period starting from when the vibration acceleration is zero; Performing Fourier transformation after zero padding on the acceleration data to obtain acceleration amplitude-frequency data; Find the frequency corresponding to the maximum amplitude from the acceleration amplitude-frequency data, and calculate the displacement amplitude of the frequency corresponding to the maximum amplitude; Perform data translation starting from the frequency corresponding to the maximum amplitude, and calculate the displacement amplitude of the frequency at adjacent positions; The maximum displacement amplitude is found from the multiple displacement amplitudes, and the corresponding frequency of the maximum displacement amplitude is used as the natural frequency value of the second-order system between the roller and the soil layer.

[0007] In some embodiments of the first aspect, the roller is a single-wheel vibratory roller, the first threshold value ranges from 17 to 22 Hz, and the second threshold value ranges from 23 to 25 Hz.

[0008] In some embodiments of the first aspect, The vibration acceleration of the roller is acquired, and the actual vibration frequency is obtained according to the vibration acceleration.

[0009] In some embodiments of the first aspect, a calculation result of multiplying a preset excitation frequency of the roller by a fixed coefficient is used as the second threshold.

[0010] In some embodiments of the first aspect, obtaining the compaction degree value of the soil layer includes: Acquire the vibration acceleration of the roller, perform zero padding on the acceleration data, and then perform Fourier transform to obtain acceleration amplitude-frequency data; Extracting the 0.5 times frequency domain amplitude and the fundamental frequency domain amplitude from the acceleration amplitude-frequency data; The compaction degree value is calculated by the following formula: , In the formula, is the compaction degree of the soil layer, is 0.5 times the frequency domain amplitude, is the frequency domain amplitude of the fundamental frequency, is the magnification factor.

[0011] In a second aspect, the present application also provides a control device for a road roller, comprising: a controller, configured to obtain a second-order system natural frequency value between the roller and the soil layer, and stop the vibration compaction operation in response to the second-order system natural frequency value reaching a first threshold; Acquiring an actual vibration frequency value of the roller, and stopping the vibration compaction operation in response to the actual vibration frequency value being less than a second threshold value; Acquiring a compaction degree value of the soil layer, and stopping the vibration compaction operation in response to the compaction degree value being greater than a third threshold value; The acceleration sensor is electrically connected to the controller and is used to obtain the vibration acceleration of the roller; the controller obtains the second-order system natural frequency value between the roller and the soil layer, the actual vibration frequency value of the roller and the compaction degree value of the soil layer according to the vibration acceleration.

[0012] In a third aspect, the present application also provides a computer device, comprising a processor and a memory connected to the processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the control method of the roller as described in any embodiment of the first aspect are performed.

[0013] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method for controlling a road roller as described in any one of the embodiments of the first aspect.

[0014] In a fifth aspect, the present application also provides a computer program product, comprising a computer program / instructions, characterized in that when the computer program / instructions are executed by a processor, the steps of the method for controlling a road roller described in any embodiment of the first aspect are implemented.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The control method and device for a road roller provided in the present application can identify abnormal working conditions in the entire process of the vibration compaction operation of the road roller and protectively stop the vibration compaction operation. It can identify the compaction state of the soil layer to prevent the road roller from over-compacting the sufficiently compacted soil layer. It can identify the vibration compaction ability of the road roller to prevent ineffective operations with uncontrollable quality. During normal vibration compaction operations, it can prevent the road roller from continuing to vibrate and damage the compacted soil layer after entering it according to the compaction degree value of the soil layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present application or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 is a flow chart of the steps of the control method of the road roller provided in this embodiment; Figure 2 is a schematic structural diagram of a control device for a road roller provided in this embodiment; Figure 3 is a schematic block diagram of the principles of the computer device provided in this embodiment; In the figure: 1. Controller; 2. Acceleration sensor. DETAILED DESCRIPTION

[0018] It should be noted that "vibration acceleration" is abbreviated as "acceleration" in some cases.

[0019] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0020] The term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship. Embodiment 1

[0021] Figure 1 This is a flow chart of a control method for a road roller in the first embodiment of the present invention. This flow chart only shows the logical sequence of the method described in this embodiment. In other possible embodiments of the present invention, different control methods may be used without conflict. Figure 1 The steps shown or described are accomplished in the order shown.

[0022] The control method of the road roller provided in this embodiment can be applied to the control module of the road roller. Figure 1 The method of this implementation specifically includes the following steps: First, the second-order system natural frequency value between the roller and the soil layer is obtained. In response to the second-order system natural frequency value reaching the first threshold, it means that the soil layer where the roller is working is already sufficiently dense to meet the design requirements, and the vibration compaction operation should be stopped to prevent continued compaction on the fully compacted layer, resulting in the destruction of the compacted layer. It is worth noting that this judgment step is mainly executed in the vibration starting stage of the roller, and the execution time is determined according to the time from the roller starting to the resonance frequency. For example, the time from the vibration starting to the resonance frequency of a type roller is usually 3s, and the execution time of this judgment step is 3.512s, ensuring that the second-order system natural frequency value between the roller and the soil layer can be collected during the vibration starting stage.

[0023] Within a certain range, the denser the soil layer, the higher the resonance frequency. Therefore, ideally, the resonance frequency between the roller and the soil layer should be obtained and compared with the set first threshold. When the resonance frequency is lower than the first threshold, it means that the soil layer on which the roller is working is not compacted and needs vibration compaction. When the resonance frequency reaches the first threshold, it means that the soil layer is compacted and work needs to be stopped to prevent the soil layer from being damaged by vibration.

[0024] However, the resonance frequency between the roller and the soil layer is difficult to measure directly in an actual construction environment. Therefore, this embodiment uses a second-order system natural frequency value between the roller and the soil layer with a similar value to replace the resonance frequency between the roller and the soil layer. The second-order system natural frequency between the roller and the soil layer can be directly or indirectly obtained by placing a sensor on the roller, which is more convenient and greatly improves the feasibility of the engineering implementation of the method, thereby ensuring that the roller can identify abnormal working conditions during the vibration starting stage and shut down protectively.

[0025] It is not difficult for those skilled in the art to see that the first threshold is set according to the designed density of the soil layer and the model of the roller, and the specific acquisition method can refer to experiments, computer simulations or empirical values.

[0026] Secondly, the actual vibration frequency value of the roller is obtained, and in response to the actual vibration frequency value being less than the second threshold value, the vibration compaction operation is stopped; this step is mainly performed after the vibration start-up stage when it is confirmed that the soil layer has not been fully vibrated and compacted, and the purpose is to verify the vibration compaction ability of the roller.

[0027] If the actual vibration frequency value reaches the second threshold value, it means that the vibration compaction capacity of the roller can meet the vibration compaction requirements of the soil layer under this thickness, and normal vibration compaction operations can be performed; if the actual vibration frequency value is less than the second threshold value, it means that the vibration compaction capacity of the roller cannot meet the vibration compaction requirements of the soil layer under this thickness, and the roller is performing ineffective compaction. In this state, the compaction quality is uncontrollable, so it is necessary to stop the roller and take treatment measures, so as to timely identify the abnormal vibration compaction operation status and make a protective shutdown.

[0028] Finally, the compaction degree value of the soil layer is obtained, and the vibration compaction operation is stopped in response to the compaction degree value being greater than the third threshold value; the roller is moving while performing vibration compaction, and the compacted soil layer and the uncompacted soil layer are difficult to distinguish with the naked eye. The driver may drive onto the compacted soil layer without knowing it, causing the compacted soil layer to be destroyed by vibration; and the significance of this step is that after entering the normal vibration compaction operation, if the roller drives onto the compacted soil layer, it can be judged that it has driven onto the compacted soil layer according to the compaction degree value of the soil layer, and then the vibration compaction operation is stopped to prevent the compacted soil layer from being destroyed.

[0029] The third threshold value can be obtained according to the compaction design index of the soil layer, or the compaction value of the compacted soil layer can be measured on site.

[0030] The method of stopping the vibration compaction operation can be implemented in other forms known in the art. For example, if the control method of the roller provided in this embodiment is deployed on the VCU of the roller, the vibration compaction operation can be stopped by issuing an instruction to cut off the power of the vibrating wheel; or, if the control method of the roller provided in this embodiment is deployed on the instrument, the driver can be reminded to stop the vibration compaction operation by issuing a warning on the instrument panel; there are even more other known forms, which will not be repeated here.

[0031] The control method for the roller provided in this embodiment can identify abnormal working conditions in the entire process of the roller's vibration compaction operation and protectively stop the vibration compaction operation. It can identify the compaction state of the soil layer to prevent the roller from over-compacting the sufficiently compacted soil layer. It can identify the vibration compaction capacity of the roller to prevent ineffective operations with uncontrollable quality. During normal vibration compaction operations, it can prevent the roller from continuing to vibrate and damage the compacted soil layer after entering it according to the compaction degree of the soil layer. Embodiment 2

[0032] This embodiment provides a control method for a road roller. This embodiment is optimized on the basis of the first embodiment to improve the technical effect and refine the technical solution. For the contents not fully described in this embodiment, please refer to the first embodiment.

[0033] Embodiment 1 mentions that the resonance frequency between the roller and the soil layer is replaced by the natural frequency value of the second-order system between the roller and the soil layer. As one embodiment, the natural frequency value of the second-order system between the roller and the soil layer is obtained, including obtaining the vibration acceleration of the roller, obtaining acceleration data within a set time length starting from the vibration acceleration being zero; performing Fourier transform after zero padding on the acceleration data to obtain acceleration amplitude-frequency data; finding the corresponding frequency of the maximum amplitude from the acceleration amplitude-frequency data, and calculating the displacement amplitude of the frequency corresponding to the maximum amplitude; performing data translation starting from the frequency corresponding to the maximum amplitude, and calculating the displacement amplitude of the frequencies at adjacent positions; finding the maximum displacement amplitude from multiple displacement amplitudes, and using the corresponding frequency of the maximum displacement amplitude as the natural frequency value of the second-order system between the roller and the soil layer.

[0034] Among them, the acceleration data within the set time length is obtained from the vibration acceleration being zero, that is, the acceleration data within the set time length is obtained from the beginning of the vibration starting stage. The set time length is generally the longest time for resonance between the roller and the soil layer in theory or experience. As one embodiment, the vibration frequency of the roller vibration wheel is gradually increased within the set time length, and all vibration frequencies are traversed from 0Hz. The vibration acceleration of the roller is collected through the sensor, and the maximum displacement amplitude and its corresponding frequency are found out.

[0035] Zero padding of acceleration data is a prerequisite for Fourier transform. Fourier transform can filter out the noise in the acceleration data, ensure that the acceleration amplitude-frequency data is relatively pure, and then analyze the accurate and reliable maximum displacement amplitude.

[0036] The displacement amplitude corresponding to the maximum amplitude in the acceleration amplitude-frequency data is not necessarily the maximum displacement amplitude, but the maximum displacement amplitude is most likely to appear near the maximum amplitude. Therefore, in this embodiment, the maximum amplitude is used as the data starting point in the acceleration amplitude-frequency data, and the maximum displacement amplitudes corresponding to adjacent amplitudes are gradually collected on both sides of the data starting point. By setting a data interval, the pointer starts from the data starting point and continuously translates to both sides at the data interval. The displacement amplitude of the pointer position is calculated each time it is translated. After multiple translations, or even until the entire acceleration amplitude-frequency data is traversed, all displacement amplitudes are summarized to find the maximum displacement amplitude. The above method can significantly reduce the workload of finding the maximum displacement amplitude, and based on the acceleration data time, it can be achieved by arranging acceleration sensors on the roller, thereby reducing the deployment cost of the method.

[0037] As one embodiment, it has been verified through experiments that when the roller used is a single-wheel vibratory roller, the value range of the first threshold is 17~22Hz, and the value range of the second threshold is 23~25Hz.

[0038] As one embodiment, the actual vibration frequency can also be obtained by acquiring the vibration acceleration of the roller using an acceleration sensor and based on the vibration acceleration of the roller.

[0039] As mentioned above, the second threshold is compared with the actual vibration frequency value to determine whether the vibration compaction capacity of the roller meets the vibration compaction requirements of the soil layer below the thickness. As one embodiment, the preset excitation frequency of the roller is multiplied by a fixed coefficient as the second threshold. The fixed coefficient can take a value of 0.9, and a detection error of 10% is allowed.

[0040] As one embodiment, obtaining the compaction degree value of the soil layer includes obtaining the vibration acceleration of the roller, performing Fourier transform after zero padding on the acceleration data, and obtaining acceleration amplitude-frequency data; extracting the 0.5 times frequency domain amplitude and the base frequency domain amplitude from the acceleration amplitude-frequency data; the compaction degree value of the soil layer is obtained by calculating the following formula: , In the formula, is the compaction degree of the soil layer, is 0.5 times the frequency domain amplitude, is the frequency domain amplitude of the fundamental frequency, is the amplification factor, since the 0.5 times frequency domain amplitude The frequency domain amplitude of the fundamental frequency The gap between them is small, so it is necessary to introduce a magnification factor , to enlarge the value of the ratio, thereby making the compaction degree of the soil layer More intuitive.

[0041] A more specific example is used to illustrate the solution of this embodiment. A 22-ton fully hydraulic single-wheel vibratory roller is to perform the sixth vibration compaction operation on a water-stable layer. The acceleration sensor 2 arranged on the vibratory wheel of the roller obtains continuous acceleration data of the vibratory wheel in the vertical direction of the ground from 0 to 3.512 seconds (referred to as T1) from the time when the start button is pressed. If the sampling frequency is 1000 Hz, 3512 acceleration data are collected.

[0042] T1 is the vibration starting stage, which refers to the stage when the roller goes from non-vibration to vibration, and the vibration frequency increases from 0 Hz to the expected frequency value. Usually, this time does not exceed 10 seconds. The vibration starting time refers to the time from pressing the vibration start button. The value of the vibration starting time T1 is preferably 2.5 to 4.5 seconds.

[0043] According to the principles of physics, the natural frequency of a material is positively correlated with its stiffness, and the degree of compaction of a material is also positively correlated with its stiffness. Therefore, it can be judged that the natural frequency of a material is correlated with the degree of compaction of the material, and the degree of compaction of the material can be judged by the natural frequency of the material. Generally, for soil materials with a fixed component, the larger the natural frequency, the denser it is. On the other hand, the natural frequency is an inherent characteristic of the material and is difficult to obtain in real time, making it difficult to obtain the resonance frequency between the roller and the soil layer in real time.

[0044] However, for a specific roller, the second-order system natural frequency value of the "roller-soil layer" vibration system when the roller and the soil layer work together is correlated with the natural frequency of the target soil material and can be obtained in real time. Therefore, the second-order system natural frequency value between the roller and the soil layer is used to replace the resonance frequency between the roller and the soil layer for judgment, so as to advance the identification of the soil compaction degree to the vibration starting stage.

[0045] The time from vibration start to resonant frequency of a vibratory roller is usually about 3s. The vibration start time T1 of the sixth compaction condition of the water-stable layer is determined to be 3.512s according to previous experience, ensuring that the acceleration data within the vibration start time does contain the acceleration data at the resonant frequency. At this time, if the sampling frequency is 1000Hz, 3512 acceleration data need to be analyzed. Starting from the vibration start time 0, 512 acceleration data are sequentially intercepted, zero-filled to 2048, and then Fourier transform is performed to filter out the frequency components outside the specified frequency band such as 6~30Hz, and a set of acceleration amplitude-frequency data is obtained. The group of acceleration amplitude-frequency data is screened to obtain the maximum acceleration amplitude and its corresponding frequency, and the displacement amplitude at the corresponding frequency is calculated using the formula, and the displacement amplitude and its corresponding frequency are recorded in the first data series. Shift 40 acceleration data and repeat the above steps. After all 3512 data are processed, all displacement amplitudes and their corresponding frequencies are recorded in the first data series. The maximum displacement amplitude is screened out from the first data series, and its corresponding frequency is used as the second-order system natural frequency value between the roller and the soil layer to replace the resonance frequency for determination. The first threshold is set to 21 Hz.

[0046] Assumption 1: The second-order system natural frequency value between the roller and the soil layer is 22.5Hz, which is greater than the first threshold value, indicating that the soil layer has been fully compacted. Continuing compaction may damage the paving layer, and continuing compaction is ineffective. Therefore, compaction control is performed: stop vibration. This step completes the judgment and control of the first time period, and advances the compaction control to the vibration start stage, thereby avoiding possible destructive compaction in the future.

[0047] Assumption 2: The second-order system natural frequency value between the roller and the soil layer is 17 Hz, which is less than the first threshold. It is judged that continued compaction will make the paving layer more compact, and continued compaction is effective compaction. Therefore, compaction control is performed: continue to vibrate.

[0048] Usually, after pressing the vibration button, corresponding to the pavements of different materials with different compaction degrees, if the compaction equipment capacity can meet the compaction requirements of the compacted materials, the actual vibration frequency can be increased from 0 to the expected frequency in about 5 seconds, such as the vibration frequency of 28Hz for a single steel wheel vibratory roller or the vibration frequency of 50Hz for a double steel wheel vibratory roller. If the compaction equipment capacity cannot meet the compaction requirements of the compacted materials, the time for the actual vibration frequency to increase from 0Hz to the expected frequency (such as the vibration frequency of 28Hz for a single steel wheel vibratory roller or the vibration frequency of 50Hz for a double steel wheel vibratory roller) will be significantly prolonged. In some cases, the actual vibration frequency cannot reach the expected frequency even after 20 seconds, resulting in damage to the compacted pavement.

[0049] Based on assumption 2, after the above judgment, in the second time period T2 (T2 is preferably 5-10s), the actual vibration frequency value of the roller is obtained. The preset excitation frequency of the roller is 28Hz, the fixed coefficient is 0.9, and the second threshold is set to 25.2Hz.

[0050] Assumption 3: Perform fast Fourier transform on the actual vibration frequency value in T2, and obtain the actual vibration frequency value at the end of T2 is 22.3Hz, which is less than the second threshold value, indicating that the vibration wheel of the roller cannot complete the vibration for a long time, that is, the compaction equipment capacity does not meet the compaction requirements of the compacted material. It is judged that the quality of continued compaction is uncontrollable, that is, continued compaction is invalid, so compaction control is performed: stop vibration.

[0051] Assumption 4: Perform fast Fourier transform on the actual vibration frequency value in T2, and the actual vibration frequency value at the end of T2 is 28.3 Hz, which means that the vibration wheel of the roller can complete the vibration within the expected time, that is, the compaction equipment capacity can meet the compaction requirements of the compacted material, and it is judged that continued compaction is effective compaction, so compaction control is performed: continue to vibrate.

[0052] As one embodiment, a frequency sensor is used to measure the motor speed and convert it into the actual vibration frequency corresponding to the time point T2. Using a frequency sensor to directly measure the motor speed to obtain the actual vibration frequency is more intuitive and accurate.

[0053] Usually, after the vibration is started and the vibration frequency is close to the preset excitation frequency, the excitation frequency of the roller tends to be stable, reaching the condition that the excitation frequency is basically the same as the excitation frequency specified in the EU Technical Specification 17006:2016 Earthworks -Continuous Compaction Control (CCC) that "during the measurement, the excitation frequency should be kept within the range of Δf<2Hz". At this time, the degree of soil compaction can be determined by comparing the changes in its effective compaction work, harmonic components, and dynamic stiffness. The compaction value after T2 can be set to the ratio of the frequency domain amplitude in the vertical direction of 0.5 times the frequency domain amplitude of the fundamental frequency multiplied by the amplification factor (e.g. 1500). The compaction value obtained in this way represents the double jump degree of the vibrating wheel, which can be used to determine whether the soil is over-pressurized, and then to identify whether the roller has entered the top of the fully compacted soil layer in disguise.

[0054] Based on assumption 4, after T2, the acceleration data of 512 points at a sampling frequency of 1000 Hz are analyzed periodically in the third time period T3 (duration 0.5 s, preferably 0.5-1 s). The compaction degree value of the soil layer in each T3 period is obtained according to the acceleration data and compared with the third threshold value. The third threshold value is set to 450 and the amplification factor is 1500.

[0055] Assumption 5: In a certain T3 cycle, the compaction degree value is 500, which is greater than the third threshold value, indicating that the vibration wheel has serious double jumps, and the vibration compaction operation of the uncompacted part may have been completed, and it has entered the compacted area. Continuing compaction will damage the pavement, and it is judged that continuing compaction is invalid, so compaction control is performed: stop vibration. Through the detection and judgment of this step, it can be judged whether the subsequent compaction is effective when the excitation frequency is basically stable and controlled. Embodiment 3

[0056] This embodiment provides a control device for a road roller, referring to Figure 2 , including, a controller 1, for obtaining a second-order system natural frequency value between the roller and the soil layer, and stopping the vibration compaction operation in response to the second-order system natural frequency value reaching a first threshold value; Acquiring an actual vibration frequency value of the road roller, and stopping the vibration compaction operation in response to the actual vibration frequency value being less than a second threshold value; Acquiring a compaction degree value of the soil layer, and stopping the vibration compaction operation in response to the compaction degree value being greater than a third threshold value; The acceleration sensor 2 is electrically connected to the controller 1 and is used to obtain the vibration acceleration of the roller; the controller 1 obtains the second-order system natural frequency value between the roller and the soil layer, the actual vibration frequency value of the roller and the compaction degree value of the soil layer according to the vibration acceleration.

[0057] Among them, the second-order system natural frequency value between the roller and the soil layer is obtained, including: Obtain the vibration acceleration of the roller, and obtain acceleration data within a set time period starting from when the vibration acceleration is zero; The acceleration data is zero-filled and then Fourier transformed to obtain the acceleration amplitude-frequency data; Find the frequency corresponding to the maximum amplitude from the acceleration amplitude-frequency data, and calculate the displacement amplitude corresponding to the frequency of the maximum amplitude; Start data translation from the frequency corresponding to the maximum amplitude, and calculate the displacement amplitude of the frequencies at adjacent positions; The maximum displacement amplitude is found from multiple displacement amplitudes, and the corresponding frequency of the maximum displacement amplitude is taken as the natural frequency value of the second-order system between the roller and the soil layer.

[0058] The roller is a single-wheel vibratory roller, the first threshold value ranges from 17 to 22 Hz, and the second threshold value ranges from 23 to 25 Hz.

[0059] The vibration acceleration of the roller is obtained, and the actual vibration frequency is obtained according to the vibration acceleration.

[0060] The second threshold value is obtained by multiplying the preset exciting frequency of the road roller by a fixed coefficient.

[0061] Obtaining the compaction value of the soil layer includes: Obtain the vibration acceleration of the roller, perform zero padding on the acceleration data, and then perform Fourier transform to obtain the acceleration amplitude-frequency data; Extract the 0.5 times frequency domain amplitude and the fundamental frequency domain amplitude from the acceleration amplitude-frequency data; The compaction degree of the soil layer is calculated by the following formula: , In the formula, is the compaction degree of the soil layer, is 0.5 times the frequency domain amplitude, is the frequency domain amplitude of the fundamental frequency, is the magnification factor.

[0062] The control method for the road roller provided in Example 1 or 2 can be applied to the control device for the road roller provided in this embodiment, and has functional modules and beneficial effects corresponding to the execution method. The control device for the road roller provided in this embodiment has the same technical effects as those in Example 1 or 2, which will not be repeated here. Embodiment 4

[0063] This embodiment provides a computer device, including a processor and a memory connected to the processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the control method for a road roller provided in Embodiment 1 or 2 are executed.

[0064] The computer device may be a server or an electronic terminal. As one embodiment, refer to Figure 3 , the computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store data acquired and generated in the control method of the road roller. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the control method of the road roller provided in embodiment one or two is implemented.

[0065] Those skilled in the art will understand that Figure 3The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0066] The computer device provided in this embodiment has the same technical effects as those in Embodiment 1 or 2, which will not be described in detail here. Embodiment 5

[0067] This embodiment provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the steps of the control method for the road roller provided in the first or second embodiment are implemented.

[0068] The computer-readable storage medium provided in this embodiment has the same technical effects as those of Embodiment 1 or 2, which will not be described in detail here. Embodiment 6

[0069] This embodiment provides a computer program product, on which a computer program is stored, and when the program is executed by a processor, the steps of the road roller control method provided in Embodiment 1 or Embodiment 2 are implemented. The computer program product provided in this embodiment can be transmitted, distributed and downloaded in the form of a signal via the Internet.

[0070] The computer program product provided in this embodiment has the same technical effects as those of Embodiment 1 or 2, and will not be described in detail here.

[0071] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0072] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1A device that provides the functions specified in a block or multiple blocks.

[0073] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0074] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0075] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0076] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0077] 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 control method for a road roller, comprising: Acquiring a second-order system natural frequency value between the roller and the soil layer, and stopping the vibration compaction operation in response to the second-order system natural frequency value reaching a first threshold; Acquiring an actual vibration frequency value of the roller, and stopping the vibration compaction operation in response to the actual vibration frequency value being less than a second threshold value; A compaction degree value of the soil layer is obtained, and in response to the compaction degree value being greater than a third threshold value, the vibration compaction operation is stopped.

2. The control method of the road roller according to claim 1, characterized in that: The second-order system natural frequency value between the roller and the soil layer is obtained, include, Acquire the vibration acceleration of the roller, and acquire acceleration data within a set time period starting from when the vibration acceleration is zero; Performing Fourier transformation after zero padding on the acceleration data to obtain acceleration amplitude-frequency data; Find the frequency corresponding to the maximum amplitude from the acceleration amplitude-frequency data, and calculate the displacement amplitude of the frequency corresponding to the maximum amplitude; Perform data translation starting from the frequency corresponding to the maximum amplitude, and calculate the displacement amplitude of the frequency at adjacent positions; The maximum displacement amplitude is found from the multiple displacement amplitudes, and the corresponding frequency of the maximum displacement amplitude is used as the natural frequency value of the second-order system between the roller and the soil layer.

3. The control method of the road roller according to claim 1, characterized in that: The roller is a single-wheel vibratory roller, the first threshold value ranges from 17 to 22 Hz, and the second threshold value ranges from 23 to 25 Hz.

4. The control method of a road roller according to claim 1, characterized in that: The vibration acceleration of the roller is acquired, and the actual vibration frequency is obtained according to the vibration acceleration.

5. The control method of a road roller according to claim 1, characterized in that: The second threshold value is calculated by multiplying the preset excitation frequency of the roller by a fixed coefficient.

6. The control method of a road roller according to claim 1, characterized in that: The obtaining of the compaction degree value of the soil layer comprises: Acquire the vibration acceleration of the roller, perform zero padding on the acceleration data, and then perform Fourier transform to obtain acceleration amplitude-frequency data; Extracting the 0.5 times frequency domain amplitude and the fundamental frequency domain amplitude from the acceleration amplitude-frequency data; The compaction degree value is calculated by the following formula: ， In the formula, is the compaction degree of the soil layer, is 0.5 times the frequency domain amplitude, is the frequency domain amplitude of the fundamental frequency, is the magnification factor.

7. A control device for a road roller, characterized in that: include, A controller (1) is used to obtain a second-order system natural frequency value between the roller and the soil layer, and stop the vibration compaction operation in response to the second-order system natural frequency value reaching a first threshold value; Acquiring an actual vibration frequency value of the roller, and stopping the vibration compaction operation in response to the actual vibration frequency value being less than a second threshold value; Acquiring a compaction degree value of the soil layer, and stopping the vibration compaction operation in response to the compaction degree value being greater than a third threshold value; The acceleration sensor (2) is electrically connected to the controller (1) and is used to obtain the vibration acceleration of the roller; the controller (1) obtains the second-order system natural frequency value between the roller and the soil layer, the actual vibration frequency value of the roller and the compaction degree value of the soil layer based on the vibration acceleration.

8. A computer device, characterized in that: It comprises a processor and a memory connected to the processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the control method of the road roller as claimed in any one of claims 1 to 6 are executed.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method for controlling a road roller according to any one of claims 1 to 6 are implemented.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method for controlling a road roller according to any one of claims 1 to 6 are implemented.

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