Precise flow control oil brushing method for driving topological optimization roller body based on digital instruction

Abstract

The invention relates to the technical field of intelligent manufacturing equipment industry, and discloses a precise flow control oil brushing method based on digital instruction driving topological optimization roller body, which comprises the following steps: in a single contact period, performing combined execution of a forward angular displacement pulse for applying an oil film and a reverse withdrawing angular displacement pulse in an oil film non-separation window; the high-frequency component of the output torque of the motor is used for adjusting the pulse in real time to adapt to the surface appearance of a workpiece, the stirring sequence is executed in the machining interval period to maintain the homogeneity of oil components, and the internal logic of the digital instruction is reconstructed, so that the restriction of the physical form of an execution tool on the process flexibility is avoided; according to the invention, the smooth roller body with a simple form obtains a programmable subtraction control dimension, bidirectional engraving can be carried out on an oil film, self-adaptive sensing of the surface morphology of a workpiece is realized by using an endogenous signal of the motor, and the contradiction between the process and sanitary safety is solved.

Description

TECHNICAL FIELD

[0001] The application relates to a precision flow control brush oil method based on a digital instruction driven topology optimized roller body, and belongs to the technical field of intelligent manufacturing equipment industry. BACKGROUND

[0002] At present, in the automatic production process, a roller body system driven by a servo motor is used to coat a workpiece surface with liquid, which is a basic technical method. The main task of the control system is to ensure that the liquid adheres to the workpiece according to the preset requirements. In this technical field, a common implementation method is that the characteristics of the final coating form are directly determined by the geometric shape of the physical surface of the roller body, that is, uniform coating is realized by using a smooth roller body, or a textured coating is generated by using a roller body with a specific pattern.

[0003] For automatic production that needs to be compatible with multiple coating processes and at the same time meet the requirements of high cleanliness, for example, in food processing, a single physical form of roller body is difficult to meet the requirements of different processes for coating form and general hygiene standards at the same time. The production task often needs to be switched between uniform thin coating and local thick coating. The former requires the use of smooth roller body which is easy to clean, while the latter points to the use of complex textured roller body, which directly conflicts with the hardware selection of the equipment. For example, a Chinese invention patent with the publication number CN201257617Y discloses a high-precision plane forming grinding machine constant pressure flow control lubrication system. The system sets a lubricating oil containing box at a high position of the machine tool, uses gravity to form a constant pressure difference to supply oil to the downstream lubrication point, and at the same time controls the opening and closing of the oil pump through the floating switch in the oil tank to intermittently pump the backflow of lubricating oil back to the high-position containing box. The core purpose is to maintain a stable oil supply pressure. However, the control logic of this method is open-loop and passive. The essence of flow control is static flow maintenance based on fixed pressure difference and pipeline damping, which cannot actively, instantaneously and precisely dynamically adjust the fluid. It does not have the ability to respond to the changes in the micro-topography of the workpiece surface, and it is impossible to actively shape the complex three-dimensional form of the fluid coating through subtraction operation of the application process. Therefore, for the precision process that needs to control complex fluid with high viscosity and solid particles on a smooth roller body and accurately construct non-uniform coating form according to digital instructions, this control idea that relies on maintaining macro-steady state cannot meet the requirements of flexibility, precision and adaptability of the process.

[0004] The common practice in the industry is to use smooth roller bodies uniformly and try to adapt to different process targets by adjusting a single control variable such as oil supply flow, but for high-viscosity fluids containing solid particles, at a higher flow rate, the fluid is prone to slip and disordered accumulation on the smooth roller surface, which leads to a lack of stable and predictable correlation between the instructions issued by the control system and the physical form finally formed on the workpiece surface, and the consistency of product quality is difficult to guarantee. Specifically, the existing technology mainly has the following restrictions: 1. The binding relationship between tool physical form and process flexibility: a single geometric shape of the roller body cannot be compatible with differentiated coating tasks, and the process switching capability of the production line is limited by the hardware configuration; 2. Nonlinearity between control instructions and physical forming process: for complex fluids, there is no direct linear relationship between conventional control variables and the final coating form, which increases the difficulty of implementing accurate forming by the control system; 3. Conflict between process complexity and equipment hygiene conditions: the requirement to achieve complex coating forms is in conflict with the simplified and easy-to-clean hygiene specifications that equipment components must meet. Therefore, how to use a smooth roller body with a simple physical form to build a new digital instruction execution logic that can control the physical properties of complex fluids and flexibly and accurately shape the final coating form, so that the process execution capability of the equipment is no longer limited by the physical geometry of the execution components, has become a technical problem to be solved by the present application. SUMMARY

[0005] The present application provides a precision flow control brushing method based on digital instruction driving topological optimization roller body, which mainly aims to solve the problem that it is difficult to achieve complex and diverse coating tasks by using a smooth roller body with a simple physical form through conventional control methods, resulting in a conflict between the process flexibility control precision and the hygiene requirements of the equipment.

[0006] To achieve the above-mentioned purpose, the present application provides a precision flow control brushing method based on digital instruction driving topological optimization roller body, the method comprising:

[0007] Step a, generating a digital instruction sequence distributed along the predetermined path of the workpiece, and synchronizing the position of the workpiece with the rotation control of the roller body as a smooth roller body;

[0008] Step b, for the control points on the predetermined path, at least one forward angular displacement pulse Δθ + to apply the oil film, and only when the window judgment condition that the oil film is not completely separated from the workpiece and the smooth roller body is met, at least one reverse angular displacement pulse Δθ - is executed to withdraw part of the applied oil film from the workpiece;

[0009] Step c, real-time acquisition of the output torque signal of the motor driving the smooth roller body, separation of the high-frequency component generated by the interaction between the smooth roller body and the micro-topography of the workpiece surface from the output torque signal, and adjustment of the subsequent to-be-executed forward angular displacement pulse Δθ + of the angular displacement according to the high-frequency component

[0010] Step d, identifying the processing gap period between two consecutive workpieces being processed, and controlling the smooth roller body to perform a preset asymmetric bidirectional rotation stirring sequence containing different rotation speed and rotation direction combinations during the processing gap period to maintain the solid particles in the oil product in a suspended homogeneous state.

[0011] Preferably, the window determination condition that the oil film is not completely separated from the workpiece and the smooth roller body is determined by whether the energy integral value of the output torque signal in the preset high-frequency band during the execution of the reverse angular displacement pulse Δθ - exceeds a preset first threshold value, or whether the contact angular displacement of the smooth roller body relative to the workpiece is within a preset second threshold value range.

[0012] Preferably, the digital instruction sequence directly defines the net oil application or withdrawal amount at each control point, and the method further comprises: determining the combination of the angular displacement and the angular velocity of the forward angular displacement pulse Δθ + and the reverse angular displacement pulse Δθ - according to the net oil application or withdrawal amount.

[0013] Preferably, the step of adjusting the angular displacement of the subsequent to-be-executed forward angular displacement pulse Δθ + according to the high-frequency component comprises: taking the instantaneous amplitude of the high-frequency component as a feedback signal representing the surface roughness of the current contact point of the workpiece, when the amplitude of the feedback signal indicates encountering a surface protrusion, reducing the angular displacement of the subsequent forward angular displacement pulse Δθ + , and when the amplitude of the feedback signal indicates encountering a surface depression, increasing the angular displacement of the subsequent forward angular displacement pulse Δθ + .

[0014] Preferably, the asymmetric bidirectional rotation stirring sequence includes at least one high-acceleration forward rotation for generating eddy currents at the bottom of the oil product to stir up the settled solid particles, and at least one higher-acceleration reverse rotation for generating shear forces to break up the gathered solid particle groups.

[0015] Preferably, the method further comprises a system identification step before processing the workpiece: driving the smooth roller to perform a pre-set wideband excitation signal under no-load condition; monitoring and recording the output torque signal during the process, and identifying and storing one or more resonance frequencies representing the inherent characteristics of the mechanical transmission system according to the frequency spectrum analysis result of the output torque signal to form a resonance fingerprint; and the method further comprises: before executing the forward angular displacement pulse Δθ + and the reverse angular displacement pulse Δθ - , performing a notch filtering process on the upcoming pulse instruction sequence according to the resonance fingerprint; and in step c, the high-frequency component is a signal obtained by filtering and purifying the high-frequency signal in the original output torque signal according to the resonance fingerprint.

[0016] Preferably, the method further comprises: during the processing of the workpiece, continuously generating a residual signal representing the difference between the high-frequency signal in the original output torque signal and the signal obtained by filtering and purifying; performing long-period statistical analysis on the residual signal to identify whether one or more resonance frequencies have experienced persistent drift, and determine the new resonance frequency point f peak after the drift; when persistent drift is identified and meets the pre-set confidence condition, updating the corresponding old resonance frequency point f r k in the stored resonance fingerprint online, and the updating rule follows: f r k+1=f r k+α·f peak -f r k, where f r k+1 is the updated resonance frequency point, k is the index of the updating times, and α is a pre-set updating weight coefficient with a value between 0 and 1.

[0017] Preferably, the angular acceleration of the forward angular displacement pulse Δθ + and the reverse angular displacement pulse Δθ - is greater than 1000 rad / s2, and the time interval between the starting moment of the execution of the reverse angular displacement pulse Δθ - and the ending moment of the execution of the forward angular displacement pulse Δθ + triggering the current retreat action is less than 10 ms.

[0018] Preferably, the workpiece is a strip-shaped food, and the oil product is a seasoning oil containing spice particles.

[0019] Preferably, the rotation control of the smooth roller is achieved by a servo motor, and the output torque signal is the output torque signal of the servo motor.

[0020] Compared with the prior art, the present application has the following beneficial effects:

[0021] 1. By combining the forward rotation pulse of the smooth roller body with the on-demand reverse rotation pulse, the reverse rotation pulse is used to withdraw the partially applied but not completely separated oil to the roller body surface using the viscous physical properties of the oil itself. This sequence of forward application and reverse withdrawal micro-rotation operations converts the originally single-directional conveying process into a controlled process that can build up and down on the workpiece surface, enabling the smooth roller body with a fixed physical form to perform complex oil film distribution construction tasks defined by a digital instruction sequence.

[0022] 2. While performing the micro-rotation operation sequence, the output torque signal of the driving motor is monitored, and the high-frequency component reflecting the interaction between the roller body and the micro-topography of the workpiece surface is separated from the signal. This high-frequency component is used as a real-time feedback signal representing the physical form change of the workpiece surface, which is directly used to adjust the parameters of the subsequent rotation pulse to be executed, thereby converting the open-loop instruction execution process into a closed-loop adaptive process with sensing and immediate response capability for the real state of the workpiece surface, and the digital precision of the instruction is thus maintained on the physical surface full of uncertainties.

[0023] 3. Before processing, the smooth roller body is driven to execute a wideband excitation signal, and the torque response under no-load state is monitored to identify and store the resonance frequency information of the transmission system itself, forming a resonance fingerprint. In the subsequent processing process, the resonance fingerprint is not only used to purify the high-frequency torque feedback signal and filter out the artifact signal generated by the system itself vibration, but also used to pre-filter the pulse instruction to be issued, suppressing the excitation of the resonance frequency. This identification and suppression mechanism enables the system to distinguish between real topography signals from the workpiece and interference signals from its own behavior at high speed, thereby resolving the inherent constraint between running speed and sensing accuracy.

[0024] 4. For the processing flow of discrete workpieces, the method can identify the processing gap period between two consecutive workpieces, and in this gap, control the smooth roller body to execute a preset non-uniform and bidirectional rotation stirring sequence. This switches the role of the roller body in the non-working state from a coating tool to a fluid homogenizer, actively maintains the suspended homogeneous state of solid particles in the oil during the inherent downtime of the production process, and ensures that the physical components of the oil contacted by each subsequent workpiece remain consistent, thereby ensuring the continuous stability of product quality without changing the hardware configuration. BRIEF DESCRIPTION OF DRAWINGS

[0025] Fig. 1 Control flow chart for the closed-loop adaptive flow control method of the present application;

[0026] Fig. 2 Timing relationship diagram for the micro-pulse combination to build the oil film of the present application;

[0027] Fig. 3 User roles and use case diagram for the control system of the present application. DETAILED DESCRIPTION

[0028] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described in detail below. Obviously, the described embodiments are some but not all of the embodiments of the present application. It should be explained that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0029] The disclosed precision flow control brush oil method based on digital instruction driving topology optimization roller body includes four main parts of digital instruction generation and synchronization, micro-pulse combination execution, adaptive compensation based on output torque signal, and fluid homogenization of machining gap, which work together to form a closed-loop precision fluid coating control method with process adaptive capability. In a typical industrial application, such as the coating of seasoning oil containing spice particles in an automatic production line of strip-shaped food, the production task often requires compatibility of uniform thin coating and local thick coating and other processes on the same production line, and the health standard requires the use of a simple and smooth roller body, which puts high requirements on the flexibility and precision of the control method. The present method reconstructs the digital instruction execution logic of the servo driving system, uses the high dynamic response capability of the servo motor and its real-time output torque signal to realize accurate coating control of high-viscosity fluid containing solid particles. In the digital instruction generation and synchronization part, a deterministic space-time reference is established for subsequent accurate execution. The system first generates a digital instruction sequence according to the predetermined path distribution of the target oil film on the workpiece. The sequence can be configured as a one-dimensional array in data structure, the array index corresponds to the discretized position coordinates of the workpiece along the conveying path, and the values stored in the array define the net oil amount required at the coordinate point. To realize the association of instructions and physical positions, a position synchronization mechanism is established, which uses the encoder installed on the workpiece conveying system to obtain real-time position information of the workpiece, and uses the position information as a trigger signal to drive the controller to extract the instruction corresponding to the position from the digital instruction sequence and send it to the rotation control system of the smooth roller body, so as to ensure that each rotation action of the roller body acts on the target control point on the predetermined path of the workpiece.

[0030] In the micro-pulse combination execution part, the traditional continuous coating process is decomposed into a bidirectional adjustable construction process composed of high-frequency, discrete angular displacement pulses. In a single contact period of the workpiece and the smooth roller body, for each control point on the predetermined path, the control system determines a positive angular displacement pulse Δθ+ and a negative angular displacement pulse Δθ- according to the target net oil amount read from the digital instruction sequence, and controls the servo motor to output the two pulses in sequence. The positive angular displacement pulse Δθ+ is used to drive the roller body to rotate in the positive direction, and the negative angular displacement pulse Δθ- is used to drive the roller body to rotate in the negative direction.+ and a reverse angular displacement pulse Δθ - constitutes a micro-rotation operation sequence; a forward angular displacement pulse Δθ + is a forward rotation with high angular acceleration, whose set value is greater than 1000 rad / s2, and its function is to apply oil to the workpiece surface; a reverse angular displacement pulse Δθ - is a reverse rotation with high angular acceleration, which is executed on demand and its function is to retract part of the oil film that has been applied but not completely separated from the workpiece and the roller body to the roller body surface by utilizing the viscosity of the oil itself; for example, if the target oil amount of a control point is 3 units, and the application amount of a standard Δθ + pulse is 5 units, then the control system will determine a Δθ - pulse that can retract 2 units of oil, and execute it immediately after the Δθ + pulse; to ensure the effectiveness of the retraction operation, the time interval between the start time of the execution of the reverse angular displacement pulse Δθ - and the end time of the execution of the forward angular displacement pulse Δθ + that triggers this retraction action is set to be less than 10 milliseconds to ensure that the operation occurs within the physical window period when the oil film is not completely separated; the determination of this window period can be determined by one of the two rules: the first rule is based on the output torque signal, that is, the output torque signal of the driving motor is collected in real time during the execution of Δθ - pulse and the energy integral value in the preset high-frequency band is calculated, if the integral value exceeds a preset first threshold value, it is determined that the oil film is still in the connected state, and the determination of the first threshold value can be obtained by offline calibration, that is, in the critical state when the oil film is connected and separated, the corresponding energy integral value is recorded as the calibration reference; the second rule is based on angular displacement, that is, whether the contact angular displacement of the smooth roller body relative to the workpiece is within a preset second threshold value range, which corresponds to the maximum geometric size of the oil film that can maintain continuity during stretching.

[0031] In the adaptive compensation part based on the output torque signal, to overcome the influence of the randomness of the micro-topography of the workpiece surface on the coating accuracy, the system collects the output torque signal of the motor driving the smooth roller body in real time while executing the pulse sequence, and uses a digital high-pass filter to separate the high-frequency component generated by the interaction between the roller body and the micro-topography of the workpiece surface from the original signal; the instantaneous amplitude of the high-frequency component is used as a feedback signal to represent the surface roughness of the current contact point of the workpiece, a positive amplitude peak indicates that the roller body encounters a surface protrusion, and a negative amplitude valley indicates that it encounters a surface depression; the control system adjusts the subsequent forward angular displacement pulse Δθ +The angular displacement; specifically, when the feedback signal indicates an encounter with a surface protrusion, the system will decrease the next Δθ. + The angular displacement of the pulse is adjusted to compensate for overcoating caused by increased local pressure; conversely, when the pulse encounters a surface depression, the next pulse Δθ is increased. + The angular displacement of the pulse ensures that sufficient oil can still be applied in areas where contact is weakened.

[0032] To improve the signal quality and system stability of the adaptive compensation section under high dynamic operating conditions, this method also includes a system identification and active suppression procedure. Before processing the workpiece, the system first performs a system identification step. Under the condition of no-load operation of the smooth roller, the drive motor executes a preset frequency sweep excitation signal, while monitoring and recording the output torque signal during this process. By performing spectral analysis on the recorded signal, one or more resonant frequency points of the mechanical transmission system are identified, and this frequency point information is stored as a resonance fingerprint. In the subsequent processing, this resonance fingerprint is used in two aspects: first, as a filter parameter during the separation of high-frequency components, it is used to purify the original output torque signal and filter out signal artifacts generated by the system's own vibration; second, before the pulse command is sent, it is used to process the Δθ to be executed. + With Δθ - The instruction sequence undergoes notch filtering to suppress excitation at the identified resonant frequencies. Furthermore, to adapt to dynamic characteristic drift caused by equipment wear or changes in operating conditions, the system can update the resonant fingerprint online. The procedure is as follows: During processing, a residual signal representing the difference between the high-frequency signal in the original output torque signal and the filtered signal is continuously generated. Long-term statistical analysis is performed on this residual signal to identify whether a persistent drift in the resonant frequency has occurred. When a new resonant frequency point f after the drift is identified... peak When the preset confidence level condition is met, the system will update the corresponding old resonance frequency point f in the stored resonance fingerprint online. rk Its update rules follow: f rk+1 =f rk +α·(f peak -f rk In the formula, f rk+1 For the updated resonant frequency point, f rk Here, k represents the resonant frequency point before the update, k is the index of the update count, and f is the resonant frequency point before the update. peakFor the newly identified resonance frequency point, and a is a preset update weight coefficient between 0 and 1, the determination of the coefficient is based on the expectation of the system change rate, and a larger a value is suitable for a faster changing system; in the fluid homogenization part of the machining gap, in order to ensure the continuous stability of the oil component, the system identifies the machining gap period between two continuous workpieces being processed by using the workpiece position sensor, and in this gap, the smooth roller body is controlled to perform a preset asymmetric bidirectional rotation stirring sequence; the asymmetric bidirectional rotation stirring sequence is designed for the problem of particle sedimentation and aggregation in the oil containing solid particles, and the specific operation includes: at least one high acceleration forward rotation, which aims to generate vortex at the bottom of the oil to stir and roll up the settled solid particles; and at least one reverse rotation with higher acceleration, which aims to generate shear force to disperse the solid particle groups that may be aggregated in the stirring process; in this way, without adding additional hardware configuration, the oil physical components are maintained in a suspended homogeneous state, thereby ensuring the consistency of product quality.

[0033] Embodiment 1: In a flexible manufacturing unit for producing strip-shaped food, the unit needs to be compatible with two differentiated seasoning oil coating processes on the same production line, process A requires forming a uniform and thin oil film on the surface of the workpiece, and process B requires forming an uneven oil film distribution with thick middle and thin ends; in order to meet the cleaning and hygiene standards, the unit uniformly uses a smooth roller body driven by a servo motor as the coating tool; when executing process B, if the traditional control method is used, that is, by increasing the oil supply flow to try to form a local thick coating, the oil with high viscosity and containing spice particles will slip and accumulate disorderly on the surface of the smooth roller body, resulting in uncontrollable oil film morphology on the workpiece and reduced product consistency; to cope with this working condition, the manufacturing unit applies the method of the present application; first, for the target of process B, the system generates a digital instruction sequence defining the oil amount distribution along the length direction of the workpiece with thick middle and thin ends; when the workpiece enters the coating station, the position synchronization mechanism is activated, the controller reads the target oil amount from the digital instruction sequence point by point according to the real-time position of the workpiece fed back by the encoder, and converts it into a series of micro rotation operation sequences; in the two end regions of the workpiece, because the digital instruction requires less oil amount to be applied, the controller executes a combination composed of a standard forward angular displacement pulse Δθ + and a reverse angular displacement pulse Δθ - with larger angular displacement, which withdraws most of the applied oil film through the latter, thereby leaving a thin layer of oil film on the surface of the workpiece; when the workpiece travels to the middle region, because the digital instruction requires a large amount of oil to be applied, the controller changes the pulse combination and executes multiple consecutive Δθ + pulses, and only executes a Δθ -Pulses to build up a thick oil layer in the middle of the workpiece, so that the Δθ + Pulses combined with Δθ - Dynamic adjustment of the pulse combination allows the use of a single physical form of the smooth roller body to achieve the formation of an uneven oil film.

[0034] In this process, the surface irregularities of the workpiece itself due to the extrusion forming process will interfere with the execution effect of the above-mentioned pulse combination, for this reason, the adaptive compensation part based on the output torque signal runs synchronously; when the smooth roller body rolls over a small protrusion on the surface of the workpiece, a positive peak will be generated in the high-frequency component of the motor output torque, this signal is fed back to the controller, which immediately reduces the angular displacement of the next Δθ + pulse when the roller body passes through a concave area, the negative peak generated in the high-frequency component of the torque will trigger the controller to increase the angular displacement of the subsequent Δθ + pulse to compensate for the lack of oil caused by the weakening of the contact; it should be noted that the micro-rotation operation sequence provides the ability to build the macro shape of the oil film, and the adaptive compensation fine-tunes the actual physical form of the workpiece surface on this basis, the combination of the two allows the oil film distribution defined by the digital instruction sequence to be reproduced on the physical surface with random interference; In addition, in the processing flow of this discrete workpiece, the system identifies the processing gap period between two consecutive workpieces, and automatically executes the preset asymmetric bidirectional rotation stirring sequence in this gap, the eddy current generated by high acceleration forward rotation and the shear force generated by higher acceleration reverse rotation homogenize the spice particles in the oil; This homogenization process provides a stable component working medium for the subsequent coating process, which, combined with the aforementioned pulse combination and adaptive compensation mechanism, jointly acts on the final product consistency; As a result, the flexibility of the process is transferred from the geometry of the physical tool to the programming of the digital instruction sequence.

[0035] Example 2: This example carries out an experiment to quantify the profile accuracy of uneven oil film coating on a workpiece with a known surface profile using a micro-rotation operation sequence with and without adaptive compensation mechanism based on output torque signal; the test platform consists of a conveying system, a coating system and a measurement system, the conveying system includes a conveying belt driven by a servo motor, which is equipped with a position encoder with a resolution of 0.01 mm; the coating system uses a smooth roller body driven by a servo motor with high dynamic response capability, the controller of the motor can execute instructions at a frequency of 1 kHz and synchronously collect output torque signals; in order to eliminate the variables introduced by the inconsistency of the workpiece raw material itself, the experiment uses a polymer rod with a precisely machined surface as a standard workpiece, which has a sinusoidal profile with an amplitude of 0.15 mm and a wavelength of 10 mm distributed along the axial direction; the measurement system is a non-contact laser profile scanner used to measure the oil film thickness distribution on the workpiece surface after coating, with a measurement accuracy of 0.01 mm; the seasoning oil used in the experiment is a mixed oil containing spice particles, and the kinematic viscosity measured at 25°C is 500 cm.

[0036] A uniform target oil film distribution is set, i.e. an oil film with a thickness of 1.0 mm is coated in the middle 40 mm long area of the workpiece, and the oil film thickness is linearly transitioned to 0.2 mm on each of the two ends with a length of 30 mm; the experiment sets up control group A, control group B and the sample group of the present application for comparison; control group A uses the traditional control method, i.e. disabling pulse control and only controlling the oil quantity by adjusting the continuous rotation speed of the smooth roller body; control group B uses the micro-rotation operation sequence in the present application, i.e. executing forward angular displacement pulse Δθ + and reverse angular displacement pulse Δθ - , but disabling the adaptive compensation function based on the output torque signal; the sample group of the present application uses the complete method of the present application, and simultaneously enables the micro-rotation operation sequence and the adaptive compensation function; the three groups of experiments are repeated 10 times under the same environmental temperature and conveying belt speed, after each experiment, the laser profile scanner is used to measure the actual generated oil film profile, and the root mean square error (RMSE) between the profile and the target oil film distribution is calculated as the evaluation index of coating accuracy, and the average value of 10 measurements is recorded as the final result; during the experiment, it is observed by the laser profile scanner that control group A forms an uneven oil film thickness distribution on the surface of the workpiece, and does not form the preset profile; control group B can form an intermediate thick and two-end thin shape roughly consistent with the target profile, but periodic thickness fluctuations corresponding to the sine profile of the workpiece itself can be observed on its surface; the sample group of the present application forms a smooth oil film profile, and the profile fluctuations are suppressed; the quantitative evaluation results of each group are shown in Table 1.

[0037] Table 1: Comparison table of coating accuracy of test group and control group.

[0038]

[0039] Referring to Table 1, the root mean square error (RMSE) of control group A was 0.852, indicating that the traditional method could not complete the uneven coating task; the RMS error of control group B decreased to 0.213, indicating that only by performing Δθ + With Δθ - The pulse combination can effectively construct the oil film profile on the smooth roller. The root mean square error of the sample group of the present invention was further reduced to 0.047. Compared with the control group B, the reduction of its root mean square error is due to the adaptive compensation function suppressing the coating deviation caused by the surface morphology fluctuation of the workpiece itself. The experimental data shows that there is a synergistic effect between the micro-rotation operation sequence and the adaptive compensation mechanism. The former provides the ability to construct complex profiles, while the latter, on this basis, makes fine adjustments according to the actual physical shape of the workpiece to improve the profile fidelity.

[0040] To further verify the reverse angular displacement pulse Δθ - To demonstrate the decisive role of this invention in constructing complex oil film profiles and to prove that the technical effects of this invention cannot be achieved solely through unidirectional pulse adjustment, the following comparative example 1 is provided.

[0041] Comparative Example 1: This comparative example aims to verify the application of the reverse angular displacement pulse Δθ in the absence of the key technical point of this invention. - In this case, the technical solution of controlling the oil volume by adjusting the positive pulse, which is easily conceived by those skilled in the art, was used to see if it could complete the same complex oil film profile construction task as in Example 2. The test conditions were exactly the same as in Example 2, including the use of the same test platform, standard workpiece (surface machined with a sinusoidal curve profile with an amplitude of 0.15 mm and a wavelength of 10 mm), seasoning oil, and laser profile scanner. The target oil film distribution was also set to the same profile that was thick in the middle and thin at both ends (1.0 mm thick in a 40 mm long area in the middle, and linearly transitioned to 0.2 mm at each end after 30 mm). The only difference between this comparative example and the test group using the method of the present invention (i.e., the sample group of the present invention in Example 2) was the control method: the control system of this comparative example only executes angular displacement and a positive angular displacement pulse Δθ with a variable frequency. + Completely disable the reverse angular displacement pulse Δθ - To attempt to reproduce the target contour, the control program was set to perform low-frequency, small angular displacement Δθ in the regions at both ends of the workpiece. + The pulse, and in the 40 mm region in the middle of the workpiece, increases Δθ. + The pulse execution frequency and angular displacement are adjusted to attempt to build a thick coating by increasing the amount of oil applied per unit time. Meanwhile, for a fair comparison, this comparative example also uses an adaptive compensation function based on the output torque signal to adjust Δθ.+ The angular displacement of the pulse to cope with the sine profile of the workpiece surface; during the test, the oil film shape can be controlled in the thin coating area at both ends of the workpiece; but in the middle area of the workpiece where thick coating is needed, obvious oil slipping and disordered accumulation phenomenon is observed, high viscosity seasoning oil cannot form a stable and uniform thick coating on the smooth roller body surface, and the boundary of thick and thin transition area is blurred, accompanied by liquid drop hanging. This leads to irregular deviation between the final oil film profile and the target profile in 10 continuous tests. For quantitative comparison, the results of the pair of examples are compared with the control group A, the control group B and the sample group of the invention in example 2 in table 2.

[0042] Table 2: Comparison table of coating accuracy of each control method.

[0043]

[0044]

[0045] The test results show that the root mean square error value of the pair of examples is 0.437 mm. This value is better than the traditional continuous speed regulation method (control group A), but worse than the control group B (root mean square error 0.213 mm) and the test group using the method of the invention (root mean square error 0.047 mm) which also uses pulse control; the data proves that even with the adaptive compensation of the surface topography, the lack of reverse angular displacement pulse Δθ - The provided subtraction control dimension, only relying on the unidirectional incremental pulse, its technical principle itself cannot overcome the physical instability of high viscosity fluid on the smooth roller body when thick coating, and cannot realize the precise construction of complex oil film profile, which reversely proves that the proposed forward application and reverse retreat of micro pulse combination is the key to realize precise flow control and oil brushing on the smooth roller body, which has non-obviousness.

[0046] Example 3: This example combines Figs. 1 to 3 a kind of precise flow control and oil brushing method based on digital instruction driven topology optimization roller body is described, such as Fig. 1As shown, the sequence, after passing through the instruction generation and synchronization module, generates an oil quantity control instruction synchronized with the workpiece position, which is then handed over to the micro-pulse combination execution module. This module achieves bidirectional oil film construction by executing a combination of positive and negative angular displacement pulses. During this execution process, an adaptive compensation closed-loop synchronous operation based on the output torque signal utilizes the high-frequency component extracted from the motor output torque to sense the workpiece surface morphology in real time and generate pulse angular displacement adjustment instructions to be fed back to the micro-pulse combination execution module for closed-loop adjustment of pulse parameters. Simultaneously, the system can identify the processing gap between two workpieces and use this gap period to trigger the fluid homogenization module of the processing gap. This module homogenizes the flavoring oil containing solid particles by executing a stirring sequence, thereby providing a uniform oil supply to the micro-pulse combination execution module, ultimately obtaining a precision oil film product that accurately reproduces the digital instructions.

[0047] like Fig. 2 As shown, on a time axis measured in milliseconds (ms), a sequence of angular displacement pulses consisting of positive and negative angular displacement pulses, with angular displacement in degrees, is synchronously displayed with a net applied oil quantity curve measured in units. This angular displacement pulse sequence appears as a series of rectangular waves fluctuating around zero, while the net applied oil quantity presents as a stepped upward curve. This relationship indicates that by combining positive angular displacement pulses (e.g., in the 0-4 ms period) with negative angular displacement pulses (e.g., in the 8-12 ms period), the net applied oil quantity can be precisely constructed incrementally or subtractively, thereby achieving digital control of the final oil film morphology. Fig. 3 As shown, the production line operator is responsible for two tasks: configuring the brushing process and performing precision brushing. The maintenance technician is responsible for calibrating and maintaining the system. During the precision brushing process, the operator interacts with the external production line main control system and triggers the internal automatic oil homogenization process, thus forming a complete operating system that includes human-machine interaction and automated processing.

[0048] Example 4: This example relates to a procedure for off-line calibration of the control system of the method of the invention, for initializing the algorithm parameters and the physical model in the system, in a specific calibration scenario, a newly installed coating system is calibrated under no-load conditions, without contacting the workpiece, using the servo motor and its controller of the system to sequentially perform the following steps; first step, determine the cut-off frequency of the digital high-pass filter used to separate the workpiece surface topography signal, the controller drives the smooth roller body to run at a typical production speed, and during this period, the motor output torque signal is continuously collected at a sampling rate of 2 kHz, the 10-second data collected is subjected to fast Fourier transform to obtain its power spectrum, the power spectrum is analyzed to determine that under the condition of no-load interaction, the system mechanical and electrical noise is mainly concentrated in the frequency band of 0 to 20 Hz, accordingly, to filter out the noise in this frequency band while retaining the high-frequency signal generated by the workpiece surface texture, the cut-off frequency of the high-pass filter is set to 25 Hz; second step, generate a resonance fingerprint representing the inherent characteristics of the transmission system of the device; after the establishment of the reference noise model, the controller drives the smooth roller body to execute a pre-set sweep excitation signal under the same no-load condition, the signal is set as a Chirp signal that increases linearly from 10 Hz to 1000 Hz, with a duration of 5 seconds; during this process, the controller synchronously records the response data of the output torque, and performs spectral analysis on the data; to automatically identify the resonance peaks, a set of judgment logic is executed: first, calculate the average power P avg and the standard deviation σ P , then, the power P f of a frequency point is determined as a resonance peak under the condition P f >P avg +5σ P Through this procedure, the system automatically identifies a set of frequency points that meet the condition, and stores this set of frequency data as the resonance fingerprint of the device, for subsequent instruction filtering and signal purification in the processing process; third step, calibrate the retraction efficiency of the reverse angular displacement pulse Δθ - This step uses a standard oil product consistent with the physical properties of the oil product used in actual production, and uses a flat metal test plate as the workpiece; the controller executes a pre-set test sequence, which includes multiple groups of micro-rotation operations, each group consists of a forward angular displacement pulse Δθ + with a fixed angular displacement of +1.0 degrees and a reverse angular displacement pulse Δθ - with an angular displacement increasing from -0.1 degrees to -0.9 degrees; after each group of pulse operations is executed, the weight change of the test plate is weighed using a high-precision electronic balance to obtain the net oil amount applied under the group of operations; by inputting Δθ -The angular displacement and the measured net oil application amount are data fitted, and the system establishes a model describing the retraction efficiency and Δθ - The function model or lookup table between the pulse parameters; after the above three steps, the resonance fingerprint, the high-pass filter cutoff frequency, and the retraction efficiency model of the system all obtain initial values based on physical calibration, which can be used for subsequent production processing.

[0049] Example 5: This embodiment illustrates a procedure for online adaptive maintenance of the control system of the method of the present application to cope with the drift of dynamic characteristics caused by mechanical wear or environmental changes during long-term operation of the equipment; in order to cope with the situation that the resonance fingerprint determined in offline calibration no longer completely matches the current physical state of the equipment due to the possible slight wear of the transmission components of the coating system during long-term operation, the system continuously executes an online system identity adaptive program in the background during the process of normal workpiece processing; the program maintains a sliding time window with a duration of 60 minutes, and continuously calculates the power spectral density of the residual signal generated by the difference between the original output torque signal and the purified signal within the window; the system sets the trigger condition for updating the resonance fingerprint to the average power of a new frequency peak, which is 10 times the average power of the background noise in the window and lasts for more than 5 minutes; once this condition is met, the controller automatically executes the update rule in the specific embodiment to adjust the corresponding old resonance frequency point in the stored resonance fingerprint to the newly identified frequency point, thereby completing the update of the resonance suppression model without interrupting production.

[0050] This embodiment also illustrates a fast calibration procedure for coping with the replacement of batches of seasoning oil; when a new batch of oil with possible differences in physical properties is added to the tank, the system is triggered by the operator or the liquid level sensor to perform a fluid property fast calibration program; under this program, in addition to executing its preset digital instruction sequence, the system also superimposes a set of standardized test pulse sequences at specific positions of each workpiece during the coating of the first 5 workpieces on the production line, which contains reverse angular displacement pulses Δθ - with different angular acceleration values; the controller collects the peak torque of the motor output during the execution of these Δθ - pulses, which is related to the viscous resistance of the oil under the new batch; the system compares the newly collected peak torque data with the reference data calibrated in Example 4, calculates a new retraction efficiency compensation coefficient, and automatically applies this coefficient to subsequent production processing until the next oil replacement; in this way, the system can complete the compensation of the retraction efficiency model within the processing time of several workpieces after replacing the new batch of oil, and then apply the compensation coefficient for subsequent production.

[0051] Example 6: This example relates to a procedure for determining the specific parameters of an asymmetric bidirectional rotational agitation sequence to adapt to different physical properties of seasoning oil products; in one specific application scenario, when a production task requires a change of oil product batch containing larger density spice particles, an off-line calibration is performed to obtain an agitation sequence matching the physical properties of the new batch; the procedure places a smooth roller body in a transparent container filled with the oil product to be tested, and uses a machine vision camera to monitor the particle distribution state inside the container; after starting the calibration program, the controller executes the agitation sequence with a set of initial parameters including forward rotational angular acceleration, angular displacement, reverse rotational angular acceleration, and pause duration, and acquires an image of the container after execution; an image processing algorithm quantifies the homogenization degree of the oil product by calculating the pixel gray scale standard deviation of the particle distribution in the image; subsequently, the calibration program uses an iterative algorithm with homogenization efficiency as the optimization objective to adjust the parameters of the agitation sequence within a pre-set parameter range, such as angular acceleration range 500 to 5000 rad / s 2 , angular displacement range 90 to 360 degrees, and finally determines a set of parameters that can make the pixel gray scale standard deviation reach a pre-set stable threshold, such as 10% lower than the initial value, in the shortest time.

[0052] This example further describes a redundant check logic for enhancing the reliability of the oil film non-separation window judgment condition; during normal processing, the controller is configured to synchronously monitor two independent indicators for determining the window condition: one is the energy integral value of the output torque signal in a pre-set high frequency band during the execution of the reverse angular displacement pulse Δθ - , and the other is the contact angular displacement of the smooth roller body relative to the workpiece; to prevent false judgments caused by transient disturbances of a single indicator, such as electrical noise or the mixing of small air bubbles in the oil product, the control system sets the final judgment criterion as follows: only when the energy integral value is lower than its pre-set first threshold value and the contact angular displacement is also outside its pre-set second threshold range, the system determines that the oil film has separated and suppresses the subsequent withdrawal action; in addition, if the system continuously detects inconsistent results of the two indicators in multiple consecutive processing cycles, such as the energy integral value continuously being lower than the threshold value while the contact angular displacement is always within the threshold range, the system will generate a maintenance warning to prompt the need for inspection of the sensors or the physical properties of the oil product.

[0053] It is obvious to those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application.

[0054] Finally, it should be noted that the above examples are merely intended to illustrate the technical solutions of the present application and not to limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A precision flow control oiling method based on digital instruction driven topology optimization of a roller body, characterized in that, The method comprises: Step a, generating a sequence of digital instructions distributed along a predetermined path of the workpiece, and synchronizing the position of the workpiece with the rotation control of the roller body as a smooth roller body; Step b. performing at least one forward angular displacement pulse Δθ for a control point on the predetermined path within a single contact period of the workpiece with the smooth roller body + to apply an oil film, and only when a window determination condition is satisfied that the oil film is not completely separated from the workpiece and the smooth roller body, performing at least one reverse angular displacement pulse Δθ - to retract a portion of the applied oil film from the workpiece; Step c, collecting the output torque signal of the motor driving the smooth roller body in real time, separating the high-frequency component generated by the interaction between the smooth roller body and the micro-topography of the workpiece surface from the output torque signal, and adjusting the subsequent forward angular displacement pulse Δθ to be executed according to the high-frequency component + angular displacement; Step d, identifying a processing gap period between two consecutive workpieces being processed, and controlling the smooth roller body to perform a preset asymmetric bidirectional rotation stirring sequence containing different rotation speed and rotation direction combinations during the processing gap period to maintain the solid particles in the oil product in a suspended homogeneous state.

2. The method of claim 1, wherein the method is a method of precise flow control brush oiling based on topology optimization of a roll body driven by digital instructions, characterized in that, The window determination condition that the oil film is not completely separated from the workpiece and the smooth roller body is determined according to whether the energy integral value of the output torque signal in the preset high-frequency band exceeds a preset first threshold value during the execution of the reverse angular displacement pulse Δθ - or whether the contact angular displacement of the smooth roller body relative to the workpiece is within a preset second threshold value range.

3. The method of claim 1, wherein the method is a method of precise flow control brush oiling based on topology optimization of a roll body driven by digital instructions, characterized in that, The digital sequence of instructions directly defines the net oil application or withdrawal at each control point. The method further comprises determining a positive angular displacement pulse Δθ + in combination with the angular displacement and angular velocity of the negative angular displacement pulse Δθ - .

4. The method of claim 1, wherein the method is a method of precise flow control brush oiling based on topology optimization of a roll body driven by digital instructions, characterized in that, adjusting the angular displacement of the subsequent forward angular displacement pulse Δθ + comprises taking the instantaneous amplitude of the high frequency component as a feedback signal representative of the surface roughness of the current contact point of the workpiece, decreasing the angular displacement of the subsequent forward angular displacement pulse Δθ + when the amplitude of the feedback signal indicates that a surface protrusion is encountered, and increasing the angular displacement of the subsequent forward angular displacement pulse Δθ + when the amplitude of the feedback signal indicates that a surface depression is encountered.

5. The method of claim 1, wherein the method is a method of precise flow control brush oiling based on topology optimization of a roll body driven by digital instructions, characterized in that, The asymmetric bidirectional rotation stirring sequence includes at least one high-acceleration forward rotation for generating vortexes at the bottom of the oil product to stir up the settled solid particles, and at least one higher-acceleration reverse rotation for generating shear force to disperse the gathered solid particle groups.

6. The method of claim 1, wherein the method is a method of precision flow control brush oiling based on topology optimization of a roll body driven by digital instructions. The method further comprises a system identification step performed before processing the workpiece: driving the smooth roller body to perform a pre-set wideband excitation signal under no-load condition of the smooth roller body; monitoring and recording the output torque signal during the process, and identifying and storing one or more resonance frequencies representing inherent characteristics of the mechanical transmission system according to the frequency spectrum analysis result of the output torque signal to form a resonance fingerprint; and the method further comprises: before executing the forward angular displacement pulse Δθ + and the reverse angular displacement pulse Δθ - , performing notch filtering processing on the pulse instruction sequence to be executed according to the resonance fingerprint; and in step c, the high-frequency component is a signal obtained by filtering and purifying the high-frequency signal in the original output torque signal according to the resonance fingerprint.

7. The method of claim 6, wherein the method is a method of precise flow control brush oiling based on topology optimization of a roll body driven by digital instructions, characterized in that, The method also includes: during the workpiece machining process, continuously generating a residual signal representing the difference between the high-frequency signal in the original output torque signal and the signal obtained after filtering and purification; performing long-period statistical analysis on the residual signal to identify whether one or more resonant frequencies have undergone continuous drift, and determining the new resonant frequency point f after the drift. peak When a persistent drift is identified and it meets a preset confidence level, the corresponding old resonance frequency point f in the stored resonance fingerprint is updated online. r k, update rules follow: f r k+1=f r k+α·f peak -f r k, where f r k+1 is the updated resonance frequency point, k is the index of the update number, and α is the preset update weight coefficient with a value between 0 and 1.

8. The method of claim 1, wherein the method is a method of precision flow control brush oiling based on topology optimization of a roll body driven by digital instructions. forward angular displacement pulse Δθ + and reverse angular displacement pulse Δθ - have angular accelerations greater than 1000 rad / s2, and the execution start time of the reverse angular displacement pulse Δθ - is less than 10 milliseconds from the execution end time of the forward angular displacement pulse Δθ + that triggered the current back-off action.

9. The method of claim 1, wherein the method is a method of precision flow control brush oiling based on topology-optimized roller bodies driven by digital instructions, characterized in that, The rotation control of the smooth roller body is realized by a servo motor drive, and the output torque signal is the output torque signal of the servo motor.

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