CN-121798058-B - Adaptive control method for time-varying flutter stability of gear forming grinding

CN121798058BCN 121798058 BCN121798058 BCN 121798058BCN-121798058-B

Abstract

The application relates to a gear forming grinding time-varying flutter stability self-adaptive control method which comprises the steps of synchronously collecting vibration acceleration signals, grinding wheel spindle rotating speed signals, acoustic emission signals and grinding wheel spindle power signals in real time in the gear forming grinding process, carrying out on-line sensing and self-adaptive correction based on the vibration acceleration signals, the grinding wheel spindle rotating speed signals, the acoustic emission signals and the grinding wheel spindle power signals to construct a comprehensive stability index, judging a working state based on the comprehensive stability index, restricting an adjustment range of process parameters when the working state meets trigger conditions, taking the minimum adjustment range of the process parameters as a target, adjusting priority based on preset process parameters, solving an optimal adjustment instruction, and issuing the optimal adjustment instruction through a machine tool communication interface to be executed. The method has the beneficial effects that the method can carry out self-adaptive control on the time-varying flutter stability of the gear forming grinding according to the real-time signal data, and ensure that the gear forming grinding whole process can carry out high-quality processing.

Inventors

REN YINGHUI
LIU LUYAO
FENG KAI
ZHAO HONGRUI
Jiang zhongyin
LI WEI
HUANG XIANGMING

Assignees

湖南大学

Dates

Publication Date: 20260512
Application Date: 20260312

Claims (9)

1. The self-adaptive control method for the time-varying flutter stability of the gear forming grinding is characterized by comprising the following steps of: S1, synchronously acquiring vibration acceleration signals, grinding wheel spindle rotating speed signals, acoustic emission signals and grinding wheel spindle power signals in real time in the gear forming and grinding process; S2, performing on-line sensing and self-adaptive correction based on a vibration acceleration signal, a grinding wheel spindle rotating speed signal, an acoustic emission signal and a grinding wheel spindle power signal to construct a comprehensive stability index, wherein the method comprises the following steps of: S2.1, preprocessing a vibration acceleration signal, and segmenting according to sliding time windows to obtain vibration response signals corresponding to the time windows; S2.2, respectively carrying out on-line identification on each vibration response signal by adopting an operation mode analysis method, and outputting the center frequency and damping ratio of the dominant flutter mode in each time window; S2.3, mapping out a thermal load representation quantity of a grinding area based on a grinding wheel spindle power signal and a process parameter, estimating a grinding wheel abrasion state based on an acoustic emission signal, the grinding wheel spindle power signal and/or a vibration acceleration signal, constructing a state vector of a corresponding time window based on the center frequency, the damping ratio, the thermal load representation quantity and the grinding wheel abrasion state of the same time window, and carrying out rolling update on a time-varying model parameter based on the state vector; S2.4, substituting the updated time-varying model parameters into a time-varying regeneration flutter model, and solving a time-varying stability boundary by adopting a full-discrete method; S2.5, weighting and summing vibration intensity indexes, damping ratio, frequency drift amount and stability probability field to obtain a comprehensive stability index; S3, judging the working state based on the comprehensive stability index, restricting the adjustment range of the technological parameters when the working state meets the triggering condition, taking the minimum adjustment amplitude of the technological parameters as a target, adjusting the priority based on the preset technological parameters, solving the optimal adjustment instruction, and issuing the optimal adjustment instruction to be executed through a machine tool communication interface.
2. The adaptive control method for gear forming grinding time-varying chatter stability according to claim 1, wherein the calculation formula of the amplitude characteristic is either: ; Or is: ; Or is: ; Wherein, the Representing the amplitude characteristic of the t-th time window, Indicating the center frequency of the t-th time window, Frequency domain representing vibration response signal in t time window The amplitude value of the amplitude value, Representing the half-width of the frequency band.
3. The method of adaptive control of gear shaping grinding time varying chatter stability of claim 2, wherein constructing the vibration intensity index based on the amplitude characteristic and the time domain root mean square value comprises: ; Wherein, the Indicating the vibration intensity index of the t-th time window, Representing the time-domain root mean square value of the t-th time window, Representing the amplitude characteristic of the t-th time window, Representing a fusion function.
4. The adaptive control method of gear forming grinding time-varying chatter stability of claim 2, wherein the working mode analysis method comprises a random subspace identification algorithm or a recursive SSI algorithm.
5. The adaptive control method for gear forming grinding time-varying chatter stability according to claim 2, wherein mapping the thermal load characteristic of the grinding zone based on the grinding wheel spindle power signal and the process parameters comprises: Inverting the specific grinding energy based on the grinding wheel spindle power signal and the material removal rate, and obtaining the thermal load characterization quantity of the grinding area through a preset mapping relation; or, inquiring a pre-established process parameter-thermal load characterization quantity database or an empirical model to obtain the thermal load characterization quantity of the grinding area; or inputting the power signal and the technological parameters of the grinding wheel spindle into an online proxy model of the thermal-force-abrasion coupling multi-physical-field simulation model to obtain the thermal load characterization quantity of the grinding area.
6. The adaptive control method for gear shaping grinding time-varying flutter stability according to claim 2, wherein the time-varying model parameters include grinding force coefficients, process damping coefficients; the updating mode of the grinding force coefficient is as follows: ; ; Wherein, the Representing the grinding force coefficient of the t-th time window, Represents the tangential reference force coefficient, represents the temperature rise, Indicating the coefficient of thermal softening and, Indicating the coefficient of wear-passivation, A state vector representing the t-th time window, Representing the thermal load characterization of the t-th time window, Indicating an initial temperature; The updating mode of the process damping coefficient is as follows: ; Wherein, the Representing the process damping coefficient for the t-th time window, Representing the damping of the reference process, Indicating the specific grinding energy of the t-th time window, The reference ratio grinding energy is indicated, A first index is indicated as such, Representing a second index.
7. The adaptive control method of gear shaping grinding time varying chatter stability of claim 2, wherein performing monte carlo sampling simulation on the center frequency and damping ratio and constructing a stable probability field based on the time varying stability boundary comprises: random disturbance is applied to the center frequency and the damping ratio, multiple Monte Carlo sampling is carried out, the stable frequency proportion of the process parameter in multiple simulation is counted, and the stable probability field is obtained; And (3) executing the steps S2.3-S2.4 on the corresponding technological parameters, calculating the corresponding time-varying stability boundary, and calculating the spectrum radius of the time-varying stability boundary, wherein the stability judging condition is that the spectrum radius corresponding to the technological parameters is smaller than 1.
8. The gear forming grinding time-varying chatter stability adaptive control method according to claim 2, wherein S3 comprises: comparing the comprehensive stability index with a preset threshold value, and determining that the working state is stable, early-warning or unstable; When the working state meets the triggering condition, the adjusting range of the technological parameter is restrained in a high-confidence stable domain, the triggering condition is that the working state is continuous to be early warning or unstable, the Gao Zhixin stable domain is that the stable probability field corresponding to the technological parameter is larger than the stable probability field of the stable threshold, the aim of minimum technological parameter adjusting amplitude is achieved, the priority is adjusted based on the preset technological parameter, the optimal adjusting instruction is solved, and the optimal adjusting instruction is issued and executed through a machine tool communication interface.
9. The adaptive control method for gear forming grinding time-varying flutter stability according to claim 1, wherein the process parameters include a grinding wheel linear speed, a grinding depth and a feeding speed, and the adjustment priority of increasing the grinding wheel linear speed is highest, the adjustment priority of decreasing the grinding depth is medium, and the adjustment priority of decreasing the feeding speed is lowest.

Description

Adaptive control method for time-varying flutter stability of gear forming grinding Technical Field The application relates to the technical field of gear precision machining, in particular to a self-adaptive control method for the stability of gear forming and grinding time-varying chatter. Background The forming grinding is a key final machining process for obtaining the gear tooth form with high precision and high surface integrity. However, the process is essentially a strongly coupled, nonlinear dynamic system. The extremely high energy density of the grinding area causes obvious temperature rise and even phase change on the surface of the workpiece, the abrasion, crushing and adhesion of grinding wheel abrasive particles enable sharpness and morphology of the grinding wheel abrasive particles to continuously change, and in addition, the dynamic characteristics of a machine tool-clamp-grinding wheel-workpiece system under actual processing load are different from those of an idle state. Together, these factors lead to drift of critical process parameters (e.g., grinding force coefficient, process damping, contact stiffness) and system modal parameters (frequency, damping ratio) over process time/course, such that stability boundaries based on linear regenerative chatter theory are no longer fixed, exhibiting significant time-variability. In practice, stable parameters selected by a stable lobe diagram (Static Stability Lobe Diagram, SLD) which is drawn offline based on initial no-load parameters often appear, and chatter vibration is caused by boundary shrinkage in the middle and later stages of processing, so that tooth surface vibration patterns, burn and geometric accuracy are out of tolerance, and the consistency and efficiency of processing quality are seriously restricted. The prior art mainly has two types of defects, namely an off-line stability prediction method based on no-load experiment modal analysis and constant process parameters, incapability of tracking parameter time variation in a working state, limited prediction precision and easiness in misjudgment, and a passive alarm and suppression strategy based on vibration amplitude exceeding a threshold value, wherein intervention is usually carried out after chatter vibration occurs and damage is caused, and the method belongs to 'post-remediation' and lacks foreseeability. Therefore, a closed-loop intelligent control method capable of sensing the system state on line, correcting the prediction model in a rolling way and adjusting prospective parameters based on prediction is developed, and the method has important significance in guaranteeing stable, efficient and high-quality machining of the gear forming and grinding whole process. Disclosure of Invention Based on this, it is necessary to provide a gear forming grinding time-varying chatter stability adaptive control method including: S1, synchronously acquiring vibration acceleration signals, grinding wheel spindle rotating speed signals, acoustic emission signals and grinding wheel spindle power signals in real time in the gear forming and grinding process; s2, performing on-line sensing and self-adaptive correction based on a vibration acceleration signal, a grinding wheel spindle rotating speed signal, an acoustic emission signal and a grinding wheel spindle power signal to construct a comprehensive stability index; S3, judging the working state based on the comprehensive stability index, restricting the adjustment range of the technological parameters when the working state meets the triggering condition, taking the minimum adjustment amplitude of the technological parameters as a target, adjusting the priority based on the preset technological parameters, solving the optimal adjustment instruction, and issuing the optimal adjustment instruction to be executed through a machine tool communication interface. The method has the beneficial effects that the method can carry out self-adaptive control on the time-varying flutter stability of the gear forming grinding according to the real-time signal data, and ensures that the whole gear forming grinding process can stably and efficiently carry out high-quality processing. Drawings In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. Fig. 1 is a flowchart of a method for adaptively controlling the vibration stability of a gear during forming grinding according to an embodiment of the present application. FIG. 2 is a diagram of a multi-source sensing arrangement and data link in accordance with an embodiment of the present application