A method and system for risk assessment of sound and vibration and driving feedback fusion of a lifting table

Abstract

The application provides a lifting table sound vibration and driving feedback fusion risk assessment method and system, driving feedback signals such as left and right motor Hall pulses and currents are collected through a first collection module, left and right mechanical sound vibration signals are collected through a second collection module, and sound vibration characteristic information is extracted in a Hall analysis window, a fusion risk assessment module corrects sound vibration characteristic weights according to sound vibration confidence, and risk information is generated by associating driving feedback signals with sound vibration characteristic information; a safety protection execution module outputs control actions such as continuous lifting, shutdown, rollback, speed reduction, synchronous compensation or maintenance prompts according to a risk threshold and a preset priority rule. The application can provide mechanical state auxiliary feedback for a lifting table, and improve the reliability of synchronous deviation, resistance and feedback anomaly judgment.

Description

Technical Field

[0001] This invention relates to the technical field of height-adjustable desks, and in particular to a risk assessment method and system for integrating acoustic vibration and drive feedback in height-adjustable desks. Background Technology

[0002] Electric height-adjustable desks typically consist of a desktop, left and right height-adjustable columns, left and right motors, a control box, and a hand controller. To ensure smooth desktop height adjustment, current solutions generally use Hall effect sensors or encoders to collect pulse signals from the left and right motors. The control box then determines whether the left and right columns are synchronized based on the left and right pulse counts, height estimates, or speed differences. Additionally, current solutions monitor motor current, speed drop, or Hall effect pulse anomalies to detect malfunctions such as obstruction, stall, or overload.

[0003] However, the above solution has the following shortcomings: First, the Hall pulse, encoder, and current signal in the above scheme mainly reflect the electrical state or position counting results of the motor, which is difficult to fully characterize the actual operating state of mechanical transmission components such as lead screw, gearbox, guide rail, and lifting column. The increase in current may be caused by a variety of reasons such as off-center load, jamming, collision, increased friction of lead screw, or motor aging. Obstruction, off-center load, and increased friction of guide rail may all lead to an increase in current or a decrease in speed. Different fault causes often show similar electrical characteristics in the drive feedback signal, making it difficult for the system to accurately distinguish the fault type.

[0004] Secondly, when the Hall signal is lost for a short time or the connection line has poor contact, the existing solution has difficulty in determining whether the abnormality is a real mechanical stall or an abnormality in the feedback link itself. This may cause the system to misjudge the feedback link failure as a mechanical stall and execute a shutdown or reverse operation, affecting the accuracy of fault diagnosis and the reliability of system operation.

[0005] Therefore, relying solely on current and Hall signals has limited ability to assist in the identification of anomaly sources, and is prone to misjudgment or omission, affecting the reliability of risk assessment and user experience. Summary of the Invention

[0006] The purpose of this invention is to provide a risk assessment method and system that integrates acoustic vibration and drive feedback for height-adjustable desks. The technical problem it solves is to provide an assessment system that introduces mechanical acoustic vibration signals and performs correlation analysis between the mechanical acoustic vibration signals and drive feedback signals. This overcomes the shortcomings of relying solely on Hall pulses and current signals to determine the lifting status, improves the reliability of risk assessment, and reduces the probability of misjudgment.

[0007] To achieve the above objectives, the solution of the present invention is: a risk assessment system for the fusion of acoustic vibration and drive feedback of a height-adjustable desk, comprising a first acquisition module, a second acquisition module, an acoustic vibration feature extraction module, a fusion risk assessment module, and a safety protection execution module; The first acquisition module is used to acquire the drive feedback signals on the left and right sides of the height-adjustable table. The drive feedback signals include at least the Hall pulse signals of the left and right motors and the current signals of the left and right motors. The second acquisition module is used to acquire mechanical acoustic and vibration signals from the left and right sides of the adjustable table; The acoustic vibration feature extraction module is used to extract acoustic vibration feature information from mechanical acoustic vibration signals within each Hall analysis window; The integrated risk assessment module is used to form a Hall analysis window with M consecutive Hall pulses. Within the control cycle corresponding to the same Hall analysis window, the drive feedback signal and acoustic vibration characteristic information are used as data of the same time period for correlation analysis. The acoustic vibration confidence level is used to correct the weight of the acoustic vibration characteristic information in the Hall analysis window participating in the risk score calculation, and risk information is generated, where M is a preset positive integer. The safety protection execution module is used to receive risk information, compare the risk information with the corresponding risk threshold, and output control actions.

[0008] Furthermore, the second acquisition module is set at the left and right motor housings, left and right lifting columns, table legs or table frame crossbeams. The acoustic vibration feature extraction module filters, frames and calculates features of the acquired mechanical acoustic vibration signals to obtain acoustic vibration feature information of the left and right sides of the lifting table. The extracted acoustic vibration feature information includes at least one of acoustic vibration RMS, peak value, impact peak value, friction frequency band energy, rotational frequency or rotational frequency related harmonic energy, and vibration envelope stability.

[0009] Furthermore, the risk assessment module employs the Hall pulse synchronous acoustic vibration analysis method for correlation analysis, including the following steps: S301, synchronously captures mechanical acoustic vibration signals and drive feedback signals within the same Hall analysis window, and extracts acoustic vibration feature information from the mechanical acoustic vibration signals; S302, obtain the acoustic and vibration confidence level of the current Hall analysis window; S303, Generate values ​​representing the current operating state, including: Within the same Hall analysis window, the acoustic and vibration characteristics on the left and right sides and the driving feedback signals on the left and right sides are compared separately to generate multiple bilateral deviation values. And to obtain the acoustic and vibration characteristics and the instantaneous values ​​of the drive feedback signal within the current Hall analysis window, or the changes relative to the previous Hall analysis window; S304, dynamically adjust the weight of acoustic vibration feature information in risk scoring calculation based on acoustic vibration confidence level, and weight the relevant values ​​of drive feedback signal based on preset fixed weights, and fuse the adjusted values ​​to generate risk information, wherein the risk information includes at least one of synchronization deviation risk, obstruction risk, mechanical abnormality risk and feedback link abnormality risk.

[0010] Furthermore, in step S302, the acoustic vibration confidence C_sv(k) is determined based on the acoustic vibration amplitude, background noise, characteristic stability, consistency between the left and right sensors, and the consistency between the acoustic vibration characteristics and the current, Hall, and velocity signals. The acoustic vibration weights used in risk scoring calculations are adjusted by modifying the acoustic vibration characteristic information using the acoustic vibration confidence level C_sv(k); w_sv'(k)=w_sv·C_sv(k); Where w_sv is the basic weight of acoustic vibration feature information; C_sv(k) is the acoustic vibration confidence level corresponding to this window (0≤C_sv(k)≤1); w_sv'(k) is the corrected acoustic and vibration weights that actually participate in the fusion judgment; The acoustic-vibration correlation correction coefficients include at least one of w_a'(k), w_e'(k), u_p'(k), and u_cf'(k), and respectively satisfy: w_a'(k) is the modified acoustic vibration RMS weight, w_a'(k) = w_a·C_sv(k); w_e'(k) is the modified friction frequency band energy weight, w_e'(k) = w_e·C_sv(k); u_p'(k) is the modified peak value weight of acoustic vibration impact, u_p'(k) = u_p·C_sv(k); u_cf'(k) is the corrected acoustic peak factor weight, u_cf'(k)=u_cf·C_sv(k); Among them, w_a, w_e, u_p, and u_cf are the basic weights of the corresponding acoustic vibration feature information.

[0011] Furthermore, the synchronization deviation risk score S_sync(k) is calculated: S_sync(k)=w_h·N_ΔH(k)+w_v·N_ΔV(k)+w_i·N_ΔI(k)+w_a'(k)·N_ΔA(k)+w_e'(k)·N_ΔE(k); Where N_ΔH(k) represents the normalized value of the height difference between the left and right Halls; N_ΔV(k) represents the normalized value of the velocity difference between the left and right Halls; N_ΔI(k) represents the normalized value of the difference between the left and right currents; N_ΔA(k) represents the normalized value of the RMS difference between the left and right acoustic vibrations; N_ΔE(k) represents the normalized value of the energy difference between the left and right friction frequency bands; w_h, w_v, and w_i are preset weights; w_a'(k) is the acoustic vibration RMS weight corrected for acoustic vibration confidence; w_e'(k) is the friction frequency band energy weight corrected by acoustic vibration confidence; The above N_ΔH(k), N_ΔV(k), N_ΔI(k), N_ΔA(k) and N_ΔE(k) are the ratios of the corresponding measured deviation values ​​to the corresponding preset thresholds or the amplitude limiting ratios, so that the height difference, speed difference, current difference and acoustic vibration characteristic difference are included in the same synchronous deviation risk score calculation; When the synchronization deviation risk score S_sync(k) exceeds the preset risk threshold in multiple consecutive Hall analysis windows, it is determined to be a synchronization deviation risk. The fusion risk assessment module generates and outputs the synchronization deviation risk.

[0012] Furthermore, the obstacle encounter risk score S_obs(k) is calculated: S_obs(k)=u_i·N_ΔIstep(k)+u_v·N_Vdrop(k)+u_p'(k)·N_P(k)+u_cf'(k)·N_CF(k); Where N_ΔIstep(k) represents the current step increment; N_Vdrop(k) represents the degree of Hall speed decrease or the degree of Hall pulse interval lengthening; N_P(k) represents the normalized peak value of acoustic vibration impact; N_CF(k) represents the normalized value of the acoustic vibration peak factor; u_i and u_v are preset weight coefficients; u_p'(k) is the peak weight of acoustic vibration impact after acoustic vibration confidence correction; u_cf'(k) is the weight of the acoustic vibration peak factor after acoustic vibration confidence correction; The above N_ΔIstep(k), N_Vdrop(k), N_P(k) and N_CF(k) are the ratios of the corresponding measured change values ​​to the corresponding preset thresholds or the limiting ratios, so that the current change, velocity change and acoustic vibration impact characteristics are included in the same obstacle encounter risk score calculation. When the obstruction risk score S_obs(k) exceeds the preset risk threshold, and the sudden increase in current, decrease in Hall speed, and acoustic and vibration impact characteristics appear in the same Hall analysis window or adjacent windows, it is judged as an obstruction risk. The obstruction risk is generated and output by the fusion risk assessment module.

[0013] Furthermore, the integrated risk assessment module is also used to obtain the changes in the mean current, friction frequency band energy, acoustic vibration RMS, or acoustic vibration envelope instability within multiple consecutive Hall analysis windows; and to generate mechanical anomaly risks by using continuous window trend judgment. When the mean current, friction frequency band energy, acoustic vibration RMS, or acoustic vibration envelope instability gradually increase within multiple consecutive Hall analysis windows, and the trend of change continuously points to the same side, it is determined to be a mechanical anomaly risk, and the mechanical anomaly risk is generated and output. The mechanical anomaly risk includes the mechanical anomaly risk on both the left and right sides of the lifting table. The mechanical anomaly risk scores S_mech,s(k) for both the left and right sides are calculated using the following formula: S_mech,s(k)=r_i·N_Iavg,s(k)+r_a'(k)·N_A,s(k)+r_e'(k)·N_E,s(k)+r_b'(k)·N_B,s(k); Where 's' represents the left or right side; N_Iavg,s(k) represents the degree of abnormality in the mean current on this side; N_A,s(k) represents the degree of acoustic vibration RMS anomaly on this side; N_E,s(k) represents the degree of energy anomaly in the friction frequency band on this side; N_B,s(k) represents the acoustic vibration envelope instability on this side; r_i is the preset current weight, r_a'(k), r_e'(k), and r_b'(k) are the acoustic vibration related weights after acoustic vibration confidence correction, and r_a'(k) = r_a·C_sv(k), r_e'(k) = r_e·C_sv(k), r_b'(k) = r_b·C_sv(k), where r_a, r_e, and r_b are the basic weights of the corresponding acoustic vibration feature information; The fusion risk assessment module is also used to calculate the moving average of mechanical anomaly risk over Q consecutive Hall analysis windows: ; k represents the sequence number of the current Hall analysis window, q represents the summation index, q takes values ​​from 0 to Q-1, S_mech,s(kq) represents the mechanical anomaly risk score of this side within the kq-th Hall analysis window; therefore, S_mech_avg,s(k) represents the average mechanical anomaly risk score of this side within the current Hall analysis window and the preceding Q-1 consecutive Hall analysis windows; When S_mech_avg,s(k) exceeds the mechanical anomaly threshold T_mech, and the mechanical anomaly risk score on this side is greater than that on the other side within Q consecutive Hall analysis windows, it is determined that there is a mechanical anomaly risk on this side, where Q is a positive integer.

[0014] Furthermore, the integrated risk assessment module is also used to generate feedback link abnormal risk when Hall pulses are lost for a short time, pulse intervals are abnormal, or counting is discontinuous, by combining control commands, current signals, and acoustic vibration characteristic information. When the control command is still rising or falling, the motor current is within the operating current range, the acoustic vibration signal still contains periodic components consistent with the historical or predicted frequency, and there is no acoustic vibration impact peak or sudden increase in energy in the friction frequency band, it is determined to be a feedback link abnormal risk, and the feedback link abnormal risk is generated and output. The risk of anomalies in the feedback links on the left or right side of the height-adjustable desk is calculated using logical decision functions: S_fb,s(k)=U_Habn,s(k)∧U_cmd(k)∧U_Irun,s(k)∧U_rot,s(k)∧[1-U_impact,s(k)]∧[1-U_fricstep,s(k)]; Where U_Habn,s(k) represents the flag of Hall pulse anomaly on this side; U_cmd(k) represents a flag indicating whether an up or down control command is currently in effect; U_Irun,s(k) represents a flag indicating that the motor current on this side is within the operating current range; U_rot,s(k) represents a marker indicating the presence of a periodic component in the mechanical acoustic signal that is consistent with the historical or predicted frequency. U_impact,s(k) represents a marker of the presence of significant acoustic and vibrational impact; U_fricstep,s(k) represents a marker indicating the presence of a sudden increase in energy in the friction frequency band; ∧ represents a logical AND operation, [1-U_impact,s(k)] represents the occurrence of a significant acoustic vibration impact, and [1-U_fricstep,s(k)] represents the occurrence of a sudden increase in energy in the friction frequency band; The above flag values ​​are either 0 or 1. When the flag values ​​U_Habn,s(k), U_cmd(k), U_Irun,s(k), and U_rot,s(k) are all 1, and the flag values ​​U_impact,s(k) and U_fricstep,s(k) are all 0, S_fb,s(k) = 1, and it is determined that there is a suspected abnormal risk in the feedback link on this side. When the acoustic vibration confidence level is lower than the preset confidence threshold, the U_rot,s(k) flag is not used as a confirmation condition, and the system reverts to the Hall and current normal abnormal protection strategy.

[0015] Furthermore, in step S301, within each Hall analysis window, the actual speed and frequency of the motor on that side are calculated based on the Hall pulse interval. Using the motor frequency as a reference, the energy near the frequency and its harmonics is extracted from the mechanical acoustic vibration signal. The acoustic vibration RMS, peak value, impact peak value, friction frequency band energy, and envelope stability are combined to form the acoustic vibration feature set within the current Hall analysis window, which serves as the acoustic vibration feature information. When calculating the difference between the left and right sides, the Hall analysis windows on the left and right sides after the same lifting start are numbered sequentially and have the same number as the corresponding windows; or the start and end time of the Hall analysis window on one side is used as the main Hall analysis window, and the drive feedback signal and acoustic vibration characteristic information of the other side within the same time range are captured synchronously; or the timer of the control box forms a common sampling clock window as the alignment reference.

[0016] This invention also provides a risk assessment method for the fusion of acoustic vibration and drive feedback in height-adjustable desks. The method, applying the aforementioned risk assessment system for the fusion of acoustic vibration and drive feedback in height-adjustable desks, includes the following steps: S1, take the time analysis window formed by M consecutive Hall pulses as the current Hall analysis window, and within the Hall analysis window, synchronously collect the drive feedback signals and mechanical acoustic vibration signals on the left and right sides of the lifting table, and extract the features of the mechanical acoustic vibration signals to obtain acoustic vibration feature information; S2, obtain the acoustic and vibration confidence level of the current Hall analysis window; S3, perform correlation analysis between the driving feedback signal and acoustic vibration characteristic information in the Hall analysis window, correct the weight of the acoustic vibration characteristic information in the Hall analysis window for participating in the risk score calculation with acoustic vibration confidence, and generate risk information; S4, receive risk information, which includes at least one of synchronization deviation risk, obstruction risk, mechanical anomaly risk and feedback link anomaly risk, compare each risk information with the corresponding risk threshold, and output control actions according to preset priority rules; The preset priority rules include: When all risk information is within the risk threshold, execute the normal path, output normal rise and fall, and continuously monitor; When the risk of obstruction exceeds the obstruction threshold, the system outputs a shutdown or short-distance reversal action; when the risk of synchronization deviation exceeds the synchronization deviation threshold, the system outputs a speed reduction or synchronization compensation action, and when the synchronization deviation risk continues to rise, the system outputs a maintenance prompt or shutdown protection action; when the risk of mechanical abnormality exceeds the mechanical abnormality threshold, the system outputs a speed reduction, limit on lifting or lowering, or maintenance prompt action; when the risk of feedback link abnormality meets the logic judgment conditions, the system outputs a low-speed stop, prompt for inspection, or recalibration action; when multiple risks exceed their corresponding thresholds simultaneously, the system selects or combines control actions according to preset priority rules.

[0017] After adopting the above solution, the beneficial effects of the present invention are as follows: (1) The present invention introduces mechanical acoustic vibration signals based on the sound and vibration generated during the operation of the motor, lead screw, gearbox, guide rail and lifting column as an auxiliary feedback information source; the acoustic vibration signals can help reflect the friction, meshing and impact characteristics of each mechanical component, effectively making up for the deficiency of the traditional solution that only relies on Hall pulse and motor current to perceive the mechanical operating status, and realizing the supplementary perception of the mechanical lifting status of the lifting table. (2) The present invention defines the time analysis window with M consecutive Hall pulses, and the length of the window can be adaptively changed according to the actual operating conditions; within the control cycle corresponding to the analysis window, the drive feedback signal and acoustic vibration feature information are synchronously acquired and associated with risk analysis, which effectively avoids risk misjudgment caused by inconsistent time reference; at the same time, the present invention introduces an acoustic vibration confidence parameter, and corrects the weight of acoustic vibration feature information in the Hall analysis window through confidence, thereby further improving the accuracy and reliability of fusion risk assessment; (3) This invention can reduce the probability of misjudgment caused by a single current threshold judgment by cross-verifying the characteristics of current change, speed change and acoustic vibration impact within the same time window, and significantly improve the accuracy of identifying the risk of obstruction or collision. At the same time, the four types of risks generated can be explained from different fault causes for the same operating state. The risk information set formed by the calculation results provides a reliable basis for the output control action of the safety protection execution module. (4) The present invention can obtain stable and more realistic evaluation results of the operating status of the lifting table: First, in the obstruction scenario, the comprehensive judgment of the obstruction event is realized by the joint verification of the current surge, Hall drop and acoustic and vibration impact characteristics, reducing false stop or missed judgment caused by a single current threshold; Second, in the synchronization deviation scenario, the difference of left and right acoustic and vibration characteristics and the change of friction frequency band energy help to judge whether the synchronization deviation is caused by the increase of mechanical resistance on one side, thus providing a strong basis for determining the cause of the synchronization deviation and avoiding control failure or structural damage caused by blind adjustment; Third, in the Hall signal abnormality scenario, the motor still has real mechanical rotation is judged by the acoustic and vibration frequency correlation characteristics, thus distinguishing between feedback link abnormality and real mechanical stall, preventing the electrical protection action from being triggered by feedback signal abnormality, and improving the fault tolerance and diagnostic reliability of the system under sensor failure conditions. Attached Figure Description

[0018] Figure 1 This is a system structure diagram of an embodiment of the present invention.

[0019] Figure 2 This is a flowchart of the parallel processing of the drive feedback route and the acoustic vibration route in an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of the installation of the second acquisition module in an embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the logic execution process according to an embodiment of the present invention.

[0022] Figure 5 This is a schematic diagram of the process for determining the risk of synchronization deviation in an embodiment of the present invention.

[0023] Figure 6 This is a schematic diagram of the process for determining the risk of encountering obstacles in an embodiment of the present invention.

[0024] Figure 7 This is a schematic diagram of the process for determining mechanical abnormality risk according to an embodiment of the present invention.

[0025] Figure 8 This is a schematic diagram of the feedback link anomaly determination process according to an embodiment of the present invention.

[0026] Label Explanation: 1-First acquisition module, 2-Second acquisition module, 3-Acoustic and vibration feature extraction module, 4-Fusion risk assessment module, 5-Safety protection execution module, 6-Control box, 7-Lifting drive unit, 8-Desktop, 9-Left lifting column, 10-Right lifting column. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] like Figures 1-8 As shown, the present invention provides a risk assessment system for the fusion of acoustic vibration and drive feedback of a height-adjustable desk, including a first acquisition module 1, a second acquisition module 2, an acoustic vibration feature extraction module 3, a fusion risk assessment module 4, and a safety protection execution module 5.

[0029] The first acquisition module 1 is used to acquire drive feedback signals from the left and right sides of the lifting table. The drive feedback signals include at least Hall pulse signals and current signals from the left and right motors. The second acquisition module 2 is used to acquire mechanical acoustic vibration signals from the left and right sides of the lifting table. The acoustic vibration feature extraction module 3 is used to extract acoustic vibration feature information from the mechanical acoustic vibration signals. The fusion risk assessment module 4 is used to form a Hall analysis window with M consecutive Hall pulses. Within the control cycle corresponding to the same Hall analysis window, the drive feedback signals and acoustic vibration feature information are used as data of the same time period for correlation analysis. The weight of the acoustic vibration feature information in the Hall analysis window participating in the risk score calculation is corrected with the acoustic vibration confidence level, and risk information is generated, where M is a preset positive integer. The safety protection execution module 5 is used to receive the risk information, compare the risk information with the corresponding risk threshold, and output control actions.

[0030] Risk information includes at least one of the following: synchronization deviation risk, obstruction risk, mechanical anomaly risk, and feedback link anomaly risk.

[0031] Synchronization deviation risk manifests as a synchronous deviation trend between the left and right sides of the height-adjustable table. Specific scenarios include increased mechanical resistance on one side, such as increased friction in the guide rail or lead screw on one side, leading to different lifting resistance on the left and right sides, thus forming a synchronous deviation trend, or a synchronous deviation trend caused by placing a heavy object on one side. The risk of obstruction manifests as the resistance encountered during the descent of the height-adjustable table, causing a sudden increase in motor current and a decrease in movement speed, such as when the tabletop hits the chair armrest, cabinet, or human body parts during descent. Mechanical anomaly risk manifests as a continuous abnormal trend in the mechanical state on the left or right side across multiple consecutive Hall analysis windows; The risk of abnormal feedback link manifests as the control commands and the lifting table operating normally, but the Hall pulses are briefly lost, the pulse intervals are abnormal, or the counting is discontinuous.

[0032] The risk assessment module 4 calculates one or more of the following risks within the same Hall analysis window: synchronization deviation risk, obstruction risk, mechanical anomaly risk, and feedback link anomaly risk. Each risk has a corresponding risk threshold. The safety protection execution module 5 outputs control actions according to preset priority rules. The preset priority rules include: When all risk information is within the risk threshold, execute the normal path, output normal rise and fall, and continuously monitor; When the risk of obstruction exceeds the obstruction threshold, the system will output a shutdown or short-distance reversal action; when the risk of synchronization deviation exceeds the synchronization deviation threshold, the system will output a speed reduction or synchronization compensation action, and when the risk of synchronization deviation continues to rise, the system will output a maintenance prompt or shutdown protection action; when the risk of mechanical abnormality exceeds the mechanical abnormality threshold, the system will output a speed reduction, limit lifting or lowering, or maintenance prompt action; when the risk of feedback link abnormality meets the logic judgment condition, the system will output a low-speed stop, prompt for inspection, or recalibration action; when multiple risks exceed their corresponding risk thresholds simultaneously, the system will select or combine control actions according to preset priority rules.

[0033] The preset priority rules also include: obstruction risk takes precedence over synchronization deviation risk and mechanical anomaly risk; when obstruction risk exceeds the obstruction threshold, shutdown or short-distance reversal actions are prioritized; feedback link anomaly risk is used to distinguish between Hall feedback anomalies and actual mechanical stalls. When there is a significant increase in acoustic vibration impact or friction frequency energy, it is not prioritized as feedback link anomaly risk, but is handled in combination with obstruction risk or mechanical anomaly risk; mechanical anomaly risk is used to characterize the continuous abnormal trend of a certain side's mechanical state within multiple consecutive Hall analysis windows. When mechanical anomaly risk and synchronization deviation risk occur simultaneously, if the synchronization deviation risk exceeds the synchronization deviation threshold, and the mechanical anomaly risk on the left or right side also exceeds the mechanical anomaly threshold, the system determines that the synchronization deviation may be related to increased mechanical resistance, jamming, or friction anomalies on the corresponding side. At this time, while outputting speed reduction or synchronization compensation actions, it also outputs actions to limit lifting or maintenance prompts; when mechanical anomaly risk reaches a preset severity level, shutdown protection actions are prioritized.

[0034] 1. Describe the structure of the drive system for the height-adjustable desk; Key points combined Figure 1 The drive system structure of the height-adjustable desk includes a height-adjustable drive unit 7, which consists of a left motor, a right motor, a gearbox, and a lead screw. The gearbox serves as a speed reduction mechanism.

[0035] The height-adjustable desk includes a desktop 8 and a left lifting column 9 and a right lifting column 10 located on the left and right sides below the desktop 8. The left lifting column 9 and the right lifting column 10 are each made of an inner tube and an outer tube connected together. The inner tube can extend and retract relative to the outer tube along the axial direction. A guide rail is provided between the inner tube and the outer tube of the left lifting column 9 and the right lifting column 10. The guide rail extends along the axial direction of the column and is used to guide and constrain the lifting direction during the extension and retraction of the lifting column to ensure the linearity and stability of the lifting movement.

[0036] The left motor is fixedly installed on the crossbeam or base on the left side of the lifting table. Its power output end is sequentially connected to the left gearbox and the left lead screw to drive the inner tube of the left lifting column to extend or retract relative to the outer tube, thereby realizing the left lifting. The right motor is fixedly installed on the crossbeam or base on the right side of the lifting table. Its power output end is sequentially connected to the right gearbox and the right lead screw to drive the inner tube of the right lifting column to extend or retract relative to the outer tube, thereby realizing the right lifting. In addition, the left lifting drive unit 7 and the right lifting drive unit 7 do not use rigid synchronous linkage in the transmission link and operate independently.

[0037] It also includes a control box 6, a hand controller (not shown in the figure), and a motor drive module. The hand controller is communicatively connected to the control box and is used for the user to input lifting control commands. The motor drive module is integrated in the control box 6 and is electrically connected to the left and right motors. It is used to receive the drive signals from the control box 6 to drive the left and right motors to lift. The acoustic vibration feature extraction module 3, the fusion risk assessment module 4, and the safety protection execution module 5 are located in the control box 6. Specifically, the control box 6 is equipped with a microcontroller (MCU). The acoustic vibration feature extraction module 3, the fusion risk assessment module 4, and the safety protection execution module 5 are integrated in the MCU and implemented through embedded programs or logic circuits. The first acquisition module 1 and the second acquisition module 2 are respectively connected to the control box 6 through a wiring harness, which is a signal cable. The first acquisition module 1 transmits the acquired drive feedback signal to the control box 6, and the second acquisition module 2 transmits the acquired mechanical acoustic vibration signal to the control box 6. After receiving the drive feedback signal and the mechanical acoustic vibration signal, the control box 6 processes them through the acoustic vibration feature extraction module 3, the fusion risk assessment module 4, and the safety protection execution module 5, and then outputs the control action to the lifting drive unit 7.

[0038] The drive feedback signals acquired by the first acquisition module 1 include left and right Hall pulses, left and right motor currents, height count, and speed signals; the control box 6 also acquires the control commands input by the user, which are the user's target lifting commands.

[0039] The second acquisition module 2 is located at the left and right motor housings, left and right lifting columns, table legs, or table frame crossbeams. Preferably, the second acquisition module 2 is a left vibration sensor installed on the left lifting column 9 or the left motor housing, and a right vibration sensor installed on the right lifting column 10 or the right motor housing. The left and right vibration sensors are connected to the control box 6 via wiring harnesses to establish a communication connection with the control box 6. In other embodiments, the second acquisition module 2 may also employ one or more of the following: a MEMS accelerometer, a piezoelectric vibrating plate, a piezoelectric thin film sensor, or a microphone, without specific limitations. The second acquisition module 2 acquires the acoustic and vibration signals generated by the lifting drive unit 7 during normal lifting, re-inspection, and abnormal operation, not just the trigger signal output by the piezoelectric element at the moment of collision.

[0040] Mechanical acoustic vibration signals include, but are not limited to, acoustic vibration signals related to the friction operation of motors, lead screws, gearboxes, guide rails, and lifting columns. After receiving the mechanical acoustic vibration signals, the control box 6 performs preprocessing operations such as amplitude limiting, filtering, removal of DC components, framing, normalization, or energy calculation of specific frequency bands on the mechanical acoustic vibration signals through the acoustic vibration feature extraction module 3 to extract acoustic vibration feature information for synchronous comparison with left and right Hall pulses, left and right motor currents, height counts, and speed signals.

[0041] 2. The analytical methods for the integrated risk assessment module are explained; The risk assessment module employs the Hall pulse synchronous acoustic vibration analysis method for correlation analysis, including the following steps: S301, synchronously captures mechanical acoustic vibration signals and drive feedback signals within the same Hall analysis window, and extracts acoustic vibration feature information from the mechanical acoustic vibration signals; S302, obtain the acoustic and vibration confidence level of the current Hall analysis window; S303, generates a numerical value characterizing the current operating state, which includes two-sided bias and time-domain abrupt change bias, including: Within the same Hall analysis window, the acoustic and vibration characteristics on the left and right sides and the driving feedback signals on the left and right sides are compared separately to generate multiple bilateral deviation values. And obtain the acoustic vibration characteristic information and the instantaneous value of the driving feedback signal within the current Hall analysis window, or the change value relative to the previous Hall analysis window, as the time domain abrupt change deviation value; S304, dynamically adjust the weight of acoustic vibration characteristic information in risk scoring calculation based on acoustic vibration confidence level, and weight the relevant values ​​of drive feedback signal based on preset fixed weights, and fuse the adjusted values ​​to generate risk information. The risk information includes at least one of the aforementioned synchronization deviation risk, obstruction risk, mechanical anomaly risk and feedback link anomaly risk; wherein, synchronization deviation risk and obstruction risk are generated through risk scoring, mechanical anomaly risk is generated through trend comparison within multiple consecutive Hall analysis windows, and feedback link anomaly risk is generated through a combination of Hall pulse state, current signal and acoustic vibration characteristic information.

[0042] In this specific embodiment, the MCU of the control box 6 can capture Hall pulse timestamps through external interrupts or timers, collect motor current and acoustic vibration signals through ADC, I2C, SPI or other interfaces, and extract the corresponding analysis window from the acoustic vibration sampling buffer according to the Hall timestamps.

[0043] To reduce the computational load on control box 6, for specific scenarios in this embodiment where only Hall frequency and a small amount of harmonic energy need to be extracted, full-band spectrum analysis is not required. Specifically, the acoustic vibration RMS, peak value, peak factor, energy after bandpass filtering, Goertzel algorithm, or simplified FFT can all be used for the above feature calculations. Preferably, the Goertzel algorithm or bandpass filtering plus energy statistics method is used for calculation to reduce the computing power and hardware cost of control box 6 while taking into account the feature extraction effect.

[0044] In this specific embodiment, in step S301, the arrival time of the kth Hall pulse of the left motor or the right motor is set to t_i(k), and a Hall analysis window is formed by M consecutive Hall pulses: W_i(k)=[t_i(k),t_i(k+M)]; Where i represents the left or right side, M is the preset number of pulses, and M is a positive integer. The specific setting depends on the motor Hall resolution, lifting speed and the computing power of the control box 6. When M is smaller, the response speed is faster, and when M is larger, the acoustic vibration characteristics are more stable.

[0045] When calculating the difference between the left and right sides, the Hall analysis windows on the left and right sides after the same lifting start are numbered sequentially and have the same number as the corresponding windows; or the start and end time of the Hall analysis window on one side is used as the main Hall analysis window, and the drive feedback signal and acoustic vibration characteristic information of the other side within the same time range are captured synchronously; or the timer of the control box forms a common sampling clock window as the alignment reference.

[0046] The aforementioned corresponding windows refer to windows with the same number after being numbered in the order of their formation, starting from the same lift-off start time; the main side Hall analysis window refers to the window whose start and end time is taken as the time boundary, either the left or right side Hall analysis window; the common sampling clock window refers to a fixed time window formed by the timer in the control box 6; for example, the kth Hall analysis window on the left is W_L(k), and the kth Hall analysis window on the right is W_R(k), and the two can be used as corresponding windows within the same control cycle to calculate the difference between the left and right sides.

[0047] Within each Hall analysis window, the actual speed and rotational frequency of the motor on that side are calculated based on the corresponding Hall pulse interval. Using this rotational frequency as a reference, the energy near the rotational frequency and its harmonics is extracted from the spectrum of the mechanical acoustic vibration signal. The extracted energy near the rotational frequency and its harmonics is combined with the acoustic vibration RMS, peak value, impact peak value, friction frequency band energy, and envelope stability of the mechanical acoustic vibration signal to form the acoustic vibration feature set within the current Hall analysis window. This acoustic vibration feature information includes acoustic vibration RMS, peak value, impact peak value, specific frequency band energy, friction frequency band energy, rotational frequency or frequency-related harmonics, vibration envelope, characteristic stability, and differences in acoustic vibration features between the left and right sides. Specifically, the rotational frequency and harmonic energy are used to determine whether the acoustic vibration signal is related to the actual rotation of the motor, while the friction frequency band energy and envelope stability are used to help reflect the mechanical state of the lead screw, guide rail, gearbox, or lifting column.

[0048] In step S303, the bilateral deviation values ​​include at least the left and right acoustic vibration RMS difference, the left and right friction frequency band energy difference, the left and right Hall height difference, the left and right Hall speed difference, and the left and right current difference. The time-domain abrupt change deviation values ​​include at least the current step increment, the change in motor speed characterized by the Hall pulse interval change, the acoustic vibration impact peak value, and the acoustic vibration peak factor. The change in motor speed characterized by the Hall pulse interval change includes at least one of the Hall speed decrease degree or the Hall pulse interval lengthening degree. The left and right acoustic vibration RMS difference refers to the difference between the mechanical acoustic vibration signals on both sides within the same Hall. The RMS characteristic difference in the analysis window reflects the consistency of vibration amplitude on the left and right sides of the lifting table; the energy difference in the left and right friction frequency bands refers to the energy difference between the left and right sides within the preset friction-related frequency bands, used to help determine whether there are differences in the friction state of the lead screw, guide rail, gearbox, or lifting column; the height difference between the left and right Halls is the height difference calculated based on Hall pulses or encoder counts; the speed difference between the left and right Halls refers to the difference in operating speed between the left and right sides of the lifting table calculated based on the Hall pulse interval or the number of Hall pulses per unit time; the current difference between the left and right sides refers to the difference in the sampled operating current values ​​of the left and right motors.

[0049] Specifically, the risk assessment module 4 first determines the Hall analysis window and calculates and normalizes the two-sided deviation value, as well as the time-domain abrupt change deviation value and normalizes it. For synchronization deviation risk and obstruction risk, the deviation value or change value related to acoustic vibration characteristic information is dynamically weighted according to the acoustic vibration confidence level, and the deviation value or change value related to the drive feedback signal is fixedly weighted. After accumulation, the corresponding risk score is generated. For mechanical anomaly risk and feedback link anomaly risk, the corresponding risk information is generated according to the trend changes or combination conditions within multiple consecutive Hall analysis windows.

[0050] 3. The following explains the calculation and processing procedures for each risk information; 3.1 Calculation of acoustic-vibration correlation correction coefficients; In this specific embodiment, before acoustic vibration features are involved in the fusion judgment, the acoustic vibration confidence level is calculated first. The acoustic vibration confidence level C_sv(k) is determined based on the acoustic vibration amplitude, background noise, feature stability, consistency between the left and right sensors, and consistency between the acoustic vibration features and current, Hall, and velocity signals. The acoustic vibration weights of the acoustic vibration feature information involved in the risk scoring calculation are corrected through the acoustic vibration confidence level C_sv(k). w_sv'(k)=w_sv·C_sv(k); Where w_sv is the basic weight of acoustic vibration feature information; C_sv(k) is the acoustic vibration confidence level corresponding to this window (0≤C_sv(k)≤1); w_sv'(k) is the corrected acoustic and vibration weights that actually participate in the fusion judgment.

[0051] The acoustic vibration correlation correction coefficients include at least one of w_a'(k), w_e'(k), u_p'(k), and u_cf'(k), and satisfy the following conditions respectively: w_a'(k)=w_a·C_sv(k), w_e'(k)=w_e·C_sv(k), u_p'(k)=u_p·C_sv(k), u_cf'(k)=u_cf·C_sv(k); where w_a, w_e, u_p, and u_cf are the basic weights of the corresponding acoustic vibration feature information.

[0052] When C_sv(k) is lower than the preset threshold, the weight of acoustic vibration feature information is reduced, or the acoustic vibration feature information is not included in the judgment in the current analysis window, and it reverts to the Hall and current normal control mode.

[0053] 3.2 Assessment of synchronization deviation risk; Key points combined Figure 5 As shown, the synchronization deviation risk score S_sync(k) is calculated: S_sync(k)=w_h·N_ΔH(k)+w_v·N_ΔV(k)+w_i·N_ΔI(k)+w_a'(k)·N_ΔA(k)+w_e'(k)·N_ΔE(k); Where N_ΔH(k) represents the normalized value of the height difference between the left and right Halls; N_ΔV(k) represents the normalized value of the velocity difference between the left and right Halls; N_ΔI(k) represents the normalized value of the difference between the left and right currents; N_ΔA(k) represents the normalized value of the RMS difference between the left and right acoustic vibrations; N_ΔE(k) represents the normalized value of the energy difference between the left and right friction frequency bands; w_h, w_v, and w_i are preset weights; w_a'(k) is the acoustic vibration RMS weight corrected for acoustic vibration confidence; w_e'(k) is the energy weight of the friction band after acoustic vibration confidence correction.

[0054] The aforementioned N_ΔH(k), N_ΔV(k), N_ΔI(k), N_ΔA(k), and N_ΔE(k) are the ratios of the corresponding measured deviation values ​​to the corresponding preset thresholds or limiting ratios, so that height difference, speed difference, current difference, and acoustic vibration characteristic difference are included in the same synchronous deviation risk score calculation. The preset thresholds can be determined based on factory calibration values, model configuration values, or operating baselines; factory calibration values ​​refer to the reference parameters written into the control box 6 during factory testing, and operating baselines refer to the reference values ​​statistically obtained by the lifting table under normal lifting conditions.

[0055] Further focus on Figure 5 As shown, when the synchronization deviation risk score exceeds the preset risk threshold in multiple consecutive Hall analysis windows, the preset risk threshold is specifically the synchronization deviation threshold. This is determined to be a synchronization deviation risk, and the fusion risk assessment module generates and outputs the synchronization deviation risk. It also generates safety protection actions, outputting speed reduction, synchronization compensation, maintenance prompts, or shutdown protection actions. When the synchronization deviation risk score does not exceed the synchronization deviation threshold, normal acceleration and deceleration are performed, and the process continues to the next Hall analysis window.

[0056] 3.3, Assessment of Obstruction Risk (Obstruction risk is not triggered by a single acoustic / vibration peak value, but is calculated by combining current surge, Hall velocity decrease, and acoustic / vibration impact characteristics). Key points combined Figure 6 As shown, the obstacle encounter risk score S_obs(k) is calculated: S_obs(k)=u_i·N_ΔIstep(k)+u_v·N_Vdrop(k)+u_p'(k)·N_P(k)+u_cf'(k)·N_CF(k); Where N_ΔIstep(k) represents the current step increment; N_Vdrop(k) represents the degree of Hall speed decrease or the degree of Hall pulse interval lengthening; N_P(k) represents the normalized peak value of acoustic vibration impact; N_CF(k) represents the normalized value of the acoustic vibration peak factor; u_i and u_v are preset weights; u_p'(k) is the peak weight of acoustic vibration impact after acoustic vibration confidence correction; u_cf'(k) is the weight of the acoustic vibration peak factor after acoustic vibration confidence correction; The aforementioned N_ΔIstep(k), N_Vdrop(k), N_P(k), and N_CF(k) are the ratios of the corresponding measured changes to the corresponding preset thresholds or limiting ratios, so that current changes, velocity changes, and acoustic and vibration impact characteristics participate in the same obstacle encounter risk score calculation. For each normalized value in the obstacle encounter risk score, the corresponding preset thresholds are the current step threshold, velocity drop threshold, acoustic and vibration impact peak threshold, or acoustic and vibration peak factor threshold; each threshold can be determined by factory calibration, model configuration, or operating baseline and stored in control box 6.

[0057] Further focus on Figure 6 As shown, when the obstruction risk score exceeds the preset risk threshold (which is the obstruction threshold), and when a sudden increase in current, a decrease in Hall speed, and acoustic / vibration impact characteristics appear in the same or adjacent Hall analysis window, it is judged as an obstruction risk. The risk assessment module generates and outputs the obstruction risk, and generates a safety protection action, outputting a shutdown, short-distance reversal, or alarm prompt. When the obstruction risk score does not exceed the obstruction threshold, normal ascent and descent are performed, and the system continues to enter the next Hall analysis window.

[0058] 3.4 Assessment of mechanical anomaly risks; 3.4.1, focusing on Figure 7 As shown, the fusion risk assessment module is also used to obtain the change status of the average current, friction frequency band energy, acoustic vibration RMS or acoustic vibration envelope instability within multiple consecutive Hall analysis windows, and to generate mechanical anomaly risks by using continuous window trend judgment; when the average current, friction frequency band energy, acoustic vibration RMS or acoustic vibration envelope instability gradually increase within multiple consecutive Hall analysis windows, and the change trend continues to point to the same side, it is determined as a mechanical anomaly risk, and the mechanical anomaly risk is generated and output.

[0059] 3.4.2 The mechanical anomaly risk includes the mechanical anomaly risk on both the left and right sides of the lifting table. The mechanical anomaly risk scores S_mech,s(k) for both the left and right sides are calculated using the following formula: S_mech,s(k)=r_i·N_Iavg,s(k)+r_a'(k)·N_A,s(k)+r_e'(k)·N_E,s(k)+r_b'(k)·N_B,s(k); Where 's' represents the left or right side; N_Iavg,s(k) represents the degree of abnormality in the mean current on this side; N_A,s(k) represents the degree of acoustic vibration RMS anomaly on this side; N_E,s(k) represents the degree of energy anomaly in the friction frequency band on this side; N_B,s(k) represents the acoustic vibration envelope instability on this side; r_i is the preset current weight; r_a'(k) is the acoustic vibration RMS weight after acoustic vibration confidence correction; r_e'(k) is the energy weight of the friction frequency band after acoustic vibration confidence correction; r_b'(k) is the acoustic vibration envelope instability weight after acoustic vibration confidence correction; And r_a'(k)=r_a·C_sv(k), r_e'(k)=r_e·C_sv(k), r_b'(k)=r_b·C_sv(k), where r_a, r_e and r_b are the basic weights of the corresponding acoustic vibration feature information; 3.4.3, the integrated risk assessment module is also used to calculate the moving average of mechanical anomaly risk over Q consecutive Hall analysis windows: ; k represents the sequence number of the current Hall analysis window, q represents the summation index, and q takes values ​​from 0 to Q-1. S_mech,s(kq) represents the mechanical anomaly risk score for this side within the kq-th Hall analysis window. Therefore, S_mech_avg,s(k) represents the average mechanical anomaly risk score for this side within the current Hall analysis window and the preceding Q-1 consecutive Hall analysis windows. For example, when Q=3, S_mech_avg,s(k) is the average of S_mech,s(k), S_mech,s(k-1), and S_mech,s(k-2).

[0060] Further focus on Figure 7As shown, when S_mech_avg,s(k) exceeds the mechanical anomaly threshold T_mech, and the mechanical anomaly risk score on this side is greater than that on the other side for Q consecutive Hall analysis windows, it is determined that there is a mechanical anomaly risk on this side, where Q is a positive integer. A control action is generated, and the output is a speed reduction, a limitation on lifting or lowering, or a maintenance prompt action. When S_mech_avg,s(k) does not exceed the mechanical anomaly threshold T_mech, normal lifting or lowering is performed, and the process continues to the next Hall analysis window.

[0061] 3.5. Determination of feedback link anomaly risks; 3.5.1, focusing on Figure 8 As shown, the integrated risk assessment module is also used to generate feedback link abnormal risk when Hall pulses are briefly lost, pulse intervals are abnormal, or counting is discontinuous, by combining control commands, current signals, and acoustic vibration characteristic information. When the control command is still rising or falling, the motor current is within the operating current range, the acoustic vibration signal still contains periodic components consistent with the historical or predicted frequency, and there is no acoustic vibration impact peak or sudden increase in energy in the friction frequency band, it is determined to be a feedback link abnormal risk, and the feedback link abnormal risk is generated and output.

[0062] 3.5.2 The risk of abnormalities in the feedback links on the left or right side of the height-adjustable desk is calculated using logical decision functions: S_fb,s(k)=U_Habn,s(k)∧U_cmd(k)∧U_Irun,s(k)∧U_rot,s(k)∧[1-U_impact,s(k)]∧[1-U_fricstep,s(k)]; Where U_Habn,s(k) represents the flag of Hall pulse anomaly on this side; U_cmd(k) represents a flag indicating whether an up or down control command is currently in effect; U_Irun,s(k) represents a flag indicating that the motor current on this side is within the operating current range; U_rot,s(k) represents a marker indicating the presence of a periodic component in the mechanical acoustic signal that is consistent with the historical or predicted frequency. U_impact,s(k) represents a marker of the presence of significant acoustic and vibrational impact; U_fricstep,s(k) represents a marker indicating the presence of a sudden increase in energy in the friction frequency band; ∧ represents a logical AND operation, [1-U_impact,s(k)] represents the occurrence of a significant acoustic vibration impact, and [1-U_fricstep,s(k)] represents the occurrence of a sudden increase in energy in the friction frequency band; Each of the above flags takes a value of 0 or 1; U_Habn,s(k)=1: indicates that the Hall pulse on this side is abnormal; U_cmd(k)=1: indicates that there is currently an ascending or descending control command; U_Irun,s(k)=1: indicates that the current on this side is within the operating current range; U_rot,s(k)=1: indicates that there is a periodic component in the acoustic vibration that is consistent with the historical or predicted frequency; U_impact,s(k)=1: indicates that there is a significant acoustic and vibration impact; U_fricstep,s(k)=1: indicates the presence of a sudden increase in energy in the friction frequency band; Further focus on Figure 8 As shown, when the flags U_Habn,s(k), U_cmd(k), U_Irun,s(k), and U_rot,s(k) are all 1, and the flags U_impact,s(k) and U_fricstep,s(k) are all 0, S_fb,s(k) = 1, which is determined to be a suspected feedback link anomaly risk on this side. When this logical judgment condition is met, a control action is generated, such as slow stop, prompting to detect the line, or recalibration. When S_fb,s(k) = 1 is not met, the judgment is made in combination with the risk of obstruction or mechanical anomaly.

[0063] When the acoustic vibration confidence level is lower than the preset confidence threshold, the U_rot,s(k) flag is not used as a confirmation condition, and the system reverts to the Hall and current normal abnormal protection strategy.

[0064] 4. This invention also provides a risk assessment method for the fusion of acoustic vibration and drive feedback in a height-adjustable desk, comprising the following steps: S1, take the time analysis window formed by M consecutive Hall pulses as the current Hall analysis window. Within this Hall analysis window, synchronously collect the drive feedback signals and mechanical acoustic vibration signals on the left and right sides of the lifting table, and extract the features of the mechanical acoustic vibration signals to obtain acoustic vibration feature information. S2, obtain the acoustic and vibration confidence level of the current Hall analysis window; S3, perform correlation analysis between the driving feedback signal and acoustic vibration characteristic information in the Hall analysis window, correct the weight of the acoustic vibration characteristic information in the Hall analysis window for participating in the risk score calculation with acoustic vibration confidence, and generate risk information; S4 receives risk information, which includes at least one of synchronization deviation risk, obstruction risk, mechanical anomaly risk, and feedback link anomaly risk. It compares each risk information with the corresponding risk threshold and outputs control actions according to preset priority rules.

[0065] Key points combined Figure 2As shown, the first acquisition module 1 acquires the drive feedback signal and the second acquisition module 2 acquires the mechanical acoustic vibration signal, which are then processed in parallel. The output feedback processing results are then analyzed by the fusion risk assessment module.

[0066] Key points combined Figure 4 As shown, the risk assessment logic for the fusion of driving feedback signals and acoustic vibration characteristic information is as follows: within the current Hall analysis window, when all risk information is within the risk threshold, the normal path is executed, the normal rise and fall is output and continuous monitoring is performed; When at least one of the risks of synchronization deviation, obstruction, mechanical abnormality, and feedback link abnormality exceeds the risk threshold, control actions are executed according to preset priority rules based on the changes in the drive feedback signal and acoustic vibration characteristic information in the corresponding Hall analysis window. The control actions are actions at the control strategy level, including continuing to lift, stopping, short-distance retraction, speed reduction, synchronization compensation, limiting lifting, maintenance prompts, prompts for inspection or recalibration, and are not limited to the underlying PWM signal output by the motor drive module.

[0067] After completing the control action, re-enter the next Hall analysis window for evaluation.

[0068] When the synchronization deviation risk score S_sync(k) exceeds the preset synchronization deviation threshold in multiple consecutive Hall analysis windows, it is determined to be a synchronization deviation risk, and speed reduction or synchronization compensation is performed; when the synchronization deviation risk continues to rise, a maintenance prompt or shutdown protection is output.

[0069] When the obstacle risk score S_obs(k) exceeds the preset obstacle threshold, and the current surge, Hall speed decrease and acoustic vibration impact characteristics appear in the same Hall analysis window or adjacent windows, it is judged as an obstacle risk, and a shutdown or short-distance rollback is executed. Weights and risk thresholds can be determined through factory calibration, model configuration, or operating baseline learning. Risk thresholds include synchronization deviation threshold, obstruction threshold, mechanical anomaly threshold, and feedback link anomaly threshold. Specifically, Hall, current, and acoustic vibration data are collected under no-load normal lifting, rated load, off-center load, simulated obstruction, and simulated Hall pulse loss conditions. Normal baseline, synchronization deviation threshold, obstruction threshold, mechanical anomaly threshold, and feedback link anomaly judgment parameters are determined respectively, and the calibration data is stored in control box 6.

[0070] The trend of features within multiple consecutive Hall analysis windows is compared. When the average current, friction frequency band energy, acoustic vibration RMS, or acoustic vibration envelope instability on a certain side gradually increases within multiple consecutive Hall analysis windows, and the change continues to be biased towards the same side, it is judged as a mechanical abnormality risk, and speed reduction, lifting and lowering restriction, or maintenance prompts are executed. When Hall pulses are briefly lost, pulse intervals are abnormal, or counting is discontinuous, a judgment is made based on the characteristics of current and acoustic vibration frequency. If the control command is still rising or falling, the motor current is within the operating current range, the acoustic vibration signal still contains periodic components consistent with the historical or predicted frequency, and there is no obvious acoustic vibration impact peak or sudden increase in energy in the severe friction frequency band, it is determined to be a risk of abnormal feedback link, and low-speed stop, prompting to check the Hall line, recalibrate, or rollback to the normal safety strategy is executed.

[0071] In this specific implementation, synchronization deviation risk, obstruction risk, mechanical anomaly risk, and feedback link anomaly risk are not mutually exclusive risk types. The integrated risk assessment module can calculate or judge the above risks separately within the same Hall analysis window to form a risk information set. When two or more risks simultaneously meet the corresponding judgment conditions, the safety protection execution module selects or combines control actions according to preset priority rules.

[0072] This invention sets independent risk thresholds for the synchronization deviation risk, obstruction risk, mechanical anomaly risk, and feedback link anomaly risk generated after fusion calculation, forming differentiated risk judgment benchmarks. When only one risk exceeds the threshold, the safety protection execution module directly executes the control action corresponding to that risk, ensuring a fast and accurate response. When two or more risks exceed their respective thresholds simultaneously, the safety protection execution module selects to execute the control action corresponding to the risk with the highest priority according to preset priority rules, or combines multiple control actions and outputs them, achieving orderly and coordinated response under multiple risk conditions. The hierarchical decision-making and flexible execution mechanism effectively avoids overreaction or false triggering in single risk scenarios, and ensures the orderliness and rationality of control actions in multiple concurrent risk scenarios. Especially when risks overlap or sensor signals are abnormal, it can significantly improve the ability to identify the cause of the anomaly and the targeting of the control action, reduce misjudgment, and distinguish the source of the anomaly, thereby enhancing the robustness of the lifting table's operation control as a whole and effectively ensuring the long-term stability and safety of the lifting table.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the design of this case. All equivalent changes made based on the key design features of this case shall fall within the protection scope of this case.

Claims

1. A risk assessment system integrating acoustic vibration and drive feedback for a height-adjustable desk, characterized in that: It includes a first acquisition module, a second acquisition module, an acoustic and vibration feature extraction module, a fusion risk assessment module, and a safety protection execution module; The first acquisition module is used to acquire the drive feedback signals on the left and right sides of the height-adjustable table. The drive feedback signals include at least the Hall pulse signals of the left and right motors and the current signals of the left and right motors. The second acquisition module is used to acquire mechanical acoustic and vibration signals from the left and right sides of the adjustable table; The acoustic vibration feature extraction module is used to extract acoustic vibration feature information from mechanical acoustic vibration signals within each Hall analysis window; The integrated risk assessment module is used to form a Hall analysis window with M consecutive Hall pulses. Within the control cycle corresponding to the same Hall analysis window, the drive feedback signal and acoustic vibration characteristic information are used as data of the same time period for correlation analysis. The acoustic vibration confidence level is used to correct the weight of the acoustic vibration characteristic information in the Hall analysis window participating in the risk score calculation, and risk information is generated, where M is a preset positive integer. The safety protection execution module is used to receive risk information, compare the risk information with the corresponding risk threshold, and output control actions.

2. The risk assessment system for the fusion of acoustic vibration and drive feedback of the height-adjustable desk as described in claim 1, characterized in that: The second acquisition module is set at the left and right motor housings, left and right lifting columns, table legs or table frame beams. The acoustic vibration feature extraction module filters, frames and calculates features of the acquired mechanical acoustic vibration signals to obtain acoustic vibration feature information of the left and right sides of the lifting table. The extracted acoustic vibration feature information includes at least one of acoustic vibration RMS, peak value, impact peak value, friction frequency band energy, rotational frequency or rotational frequency related harmonic energy, and vibration envelope stability.

3. The risk assessment system for the fusion of acoustic vibration and drive feedback of the height-adjustable desk as described in claim 1, characterized in that: The fusion risk assessment module uses the Hall pulse synchronous acoustic vibration analysis method for correlation analysis, including the following steps: S301, synchronously captures mechanical acoustic vibration signals and drive feedback signals within the same Hall analysis window, and extracts acoustic vibration feature information from the mechanical acoustic vibration signals; S302, obtain the acoustic and vibration confidence level of the current Hall analysis window; S303, Generate values ​​representing the current operating state, including: Within the same Hall analysis window, the acoustic and vibration characteristics on the left and right sides and the driving feedback signals on the left and right sides are compared separately to generate multiple bilateral deviation values. And to obtain the acoustic and vibration characteristics and the instantaneous values ​​of the drive feedback signal within the current Hall analysis window, or the changes relative to the previous Hall analysis window; S304, dynamically adjust the weight of acoustic vibration feature information in risk scoring calculation based on acoustic vibration confidence level, and weight the relevant values ​​of drive feedback signal based on preset fixed weights, and fuse the adjusted values ​​to generate risk information, wherein the risk information includes at least one of synchronization deviation risk, obstruction risk, mechanical abnormality risk and feedback link abnormality risk.

4. The risk assessment system for the fusion of acoustic vibration and drive feedback of the height-adjustable desk as described in claim 3, characterized in that: In step S302, the acoustic vibration confidence C_sv(k) is determined based on the acoustic vibration amplitude, background noise, characteristic stability, consistency of left and right sensors, and consistency of acoustic vibration characteristics with current, Hall, and velocity signals. The acoustic vibration weights used in risk scoring calculations are adjusted by modifying the acoustic vibration characteristic information using the acoustic vibration confidence level C_sv(k); w_sv'(k)=w_sv·C_sv(k); Where w_sv is the basic weight of acoustic vibration feature information; C_sv(k) is the acoustic vibration confidence level corresponding to this window (0≤C_sv(k)≤1); w_sv'(k) is the corrected acoustic and vibration weights that actually participate in the fusion judgment; The acoustic-vibration correlation correction coefficients include at least one of w_a'(k), w_e'(k), u_p'(k), and u_cf'(k), and respectively satisfy: w_a'(k) is the modified acoustic vibration RMS weight, w_a'(k) = w_a·C_sv(k); w_e'(k) is the modified friction frequency band energy weight, w_e'(k) = w_e·C_sv(k); u_p'(k) is the modified peak value weight of acoustic vibration impact, u_p'(k) = u_p·C_sv(k); u_cf'(k) is the corrected acoustic peak factor weight, u_cf'(k)=u_cf·C_sv(k); Among them, w_a, w_e, u_p, and u_cf are the basic weights of the corresponding acoustic vibration feature information.

5. The risk assessment system for the fusion of acoustic vibration and drive feedback of the height-adjustable desk as described in claim 4, characterized in that: Calculate the synchronization deviation risk score S_sync(k): S_sync(k)=w_h·N_ΔH(k)+w_v·N_ΔV(k)+w_i·N_ΔI(k)+w_a'(k)·N_ΔA(k)+w_e'(k)·N_ΔE(k); Where N_ΔH(k) represents the normalized value of the height difference between the left and right Halls; N_ΔV(k) represents the normalized value of the velocity difference between the left and right Halls; N_ΔI(k) represents the normalized value of the difference between the left and right currents; N_ΔA(k) represents the normalized value of the RMS difference between the left and right acoustic vibrations; N_ΔE(k) represents the normalized value of the energy difference between the left and right friction frequency bands; w_h, w_v, and w_i are preset weights; w_a'(k) is the acoustic vibration RMS weight corrected for acoustic vibration confidence; w_e'(k) is the friction frequency band energy weight corrected by acoustic vibration confidence; The above N_ΔH(k), N_ΔV(k), N_ΔI(k), N_ΔA(k) and N_ΔE(k) are the ratios of the corresponding measured deviation values ​​to the corresponding preset thresholds or the amplitude limiting ratios, so that the height difference, speed difference, current difference and acoustic vibration characteristic difference are included in the same synchronous deviation risk score calculation; When the synchronization deviation risk score S_sync(k) exceeds the preset risk threshold in multiple consecutive Hall analysis windows, it is determined to be a synchronization deviation risk. The fusion risk assessment module generates and outputs the synchronization deviation risk.

6. The risk assessment system for the fusion of acoustic vibration and drive feedback of the height-adjustable desk as described in claim 4, characterized in that: Calculate the obstacle encounter risk score S_obs(k): S_obs(k)=u_i·N_ΔIstep(k)+u_v·N_Vdrop(k)+u_p'(k)·N_P(k)+u_cf'(k)·N_CF(k); Where N_ΔIstep(k) represents the current step increment; N_Vdrop(k) represents the degree of Hall speed decrease or the degree of Hall pulse interval lengthening; N_P(k) represents the normalized peak value of acoustic vibration impact; N_CF(k) represents the normalized value of the acoustic vibration peak factor; u_i and u_v are preset weights; u_p'(k) is the peak weight of acoustic vibration impact after acoustic vibration confidence correction; u_cf'(k) is the weight of the acoustic vibration peak factor after acoustic vibration confidence correction; The above N_ΔIstep(k), N_Vdrop(k), N_P(k) and N_CF(k) are the ratios of the corresponding measured change values ​​to the corresponding preset thresholds or the limiting ratios, so that the current change, velocity change and acoustic vibration impact characteristics are included in the same obstacle encounter risk score calculation. When the obstruction risk score S_obs(k) exceeds the preset risk threshold, and the current surge, Hall speed decrease, and acoustic vibration impact characteristics appear in the same Hall analysis window or adjacent windows, it is judged as an obstruction risk. The obstruction risk is generated and output by the fusion risk assessment module.

7. The risk assessment system for the fusion of acoustic vibration and drive feedback of the height-adjustable desk as described in claim 4, characterized in that: The fusion risk assessment module is also used to obtain the changes in the mean current, friction frequency band energy, acoustic vibration RMS or acoustic vibration envelope instability within multiple consecutive Hall analysis windows. The system uses a continuous window trend judgment to generate mechanical anomaly risks. When the mean current, friction frequency band energy, acoustic vibration RMS or acoustic vibration envelope instability gradually increase in multiple consecutive Hall analysis windows, and the trend of change continues to point to the same side, it is judged as a mechanical anomaly risk, and the mechanical anomaly risk is generated and output. The mechanical anomaly risk includes the mechanical anomaly risk on both the left and right sides of the lifting table. The mechanical anomaly risk scores S_mech,s(k) for both the left and right sides are calculated using the following formula: S_mech,s(k)=r_i·N_Iavg,s(k)+r_a'(k)·N_A,s(k)+r_e'(k)·N_E,s(k)+r_b'(k)·N_B,s(k); Where 's' represents the left or right side; N_Iavg,s(k) represents the degree of abnormality in the mean current on this side; N_A,s(k) represents the degree of acoustic vibration RMS anomaly on this side; N_E,s(k) represents the degree of energy anomaly in the friction frequency band on this side; N_B,s(k) represents the acoustic vibration envelope instability on this side; r_i is the preset current weight, r_a'(k), r_e'(k), and r_b'(k) are the acoustic vibration related weights after acoustic vibration confidence correction, and r_a'(k) = r_a·C_sv(k), r_e'(k) = r_e·C_sv(k), r_b'(k) = r_b·C_sv(k), where r_a, r_e, and r_b are the basic weights of the corresponding acoustic vibration feature information; The fusion risk assessment module is also used to calculate the moving average of mechanical anomaly risk over Q consecutive Hall analysis windows: ； k represents the sequence number of the current Hall analysis window, q represents the summation index, q takes values ​​from 0 to Q-1, S_mech,s(kq) represents the mechanical anomaly risk score of this side within the kq-th Hall analysis window; therefore, S_mech_avg,s(k) represents the average mechanical anomaly risk score of this side within the current Hall analysis window and the preceding Q-1 consecutive Hall analysis windows; When S_mech_avg,s(k) exceeds the mechanical anomaly threshold T_mech, and the mechanical anomaly risk score on this side is greater than that on the other side within Q consecutive Hall analysis windows, it is determined that there is a mechanical anomaly risk on this side, where Q is a positive integer.

8. The risk assessment system for the fusion of acoustic vibration and drive feedback of the height-adjustable desk as described in claim 3, characterized in that: The fusion risk assessment module is also used to generate feedback link abnormal risk when Hall pulses are lost for a short time, pulse intervals are abnormal, or counting is discontinuous, by combining control commands, current signals, and acoustic vibration characteristic information. When the control command is still rising or falling, the motor current is within the operating current range, the acoustic vibration signal still contains periodic components consistent with the historical or predicted frequency, and there is no acoustic vibration impact peak or sudden increase in energy in the friction frequency band, it is determined to be a feedback link abnormal risk, and the feedback link abnormal risk is generated and output. The risk of abnormality in the feedback link on the left or right side of the height-adjustable desk is calculated using logical decision functions: S_fb,s(k)=U_Habn,s(k)∧U_cmd(k)∧U_Irun,s(k)∧U_rot,s(k)∧[1-U_impact,s(k)]∧[1-U_fricstep,s(k)]; Where U_Habn,s(k) represents the flag of Hall pulse anomaly on this side; U_cmd(k) represents a flag indicating whether an up or down control command is currently in effect; U_Irun,s(k) represents a flag indicating that the motor current on this side is within the operating current range; U_rot,s(k) represents a marker indicating the presence of a periodic component in the mechanical acoustic signal that is consistent with the historical or predicted frequency. U_impact,s(k) represents a marker of the presence of significant acoustic and vibrational impact; U_fricstep,s(k) represents a marker indicating the presence of a sudden increase in energy in the friction frequency band; ∧ represents a logical AND operation, [1-U_impact,s(k)] represents the occurrence of a significant acoustic vibration impact, and [1-U_fricstep,s(k)] represents the occurrence of a sudden increase in energy in the friction frequency band; The above flag values ​​are either 0 or 1. When the flag values ​​U_Habn,s(k), U_cmd(k), U_Irun,s(k), and U_rot,s(k) are all 1, and the flag values ​​U_impact,s(k) and U_fricstep,s(k) are all 0, S_fb,s(k) = 1, and it is determined that there is a suspected abnormal risk in the feedback link on this side. When the acoustic vibration confidence level is lower than the preset confidence threshold, the U_rot,s(k) flag is not used as a confirmation condition, and the system reverts to the Hall and current normal abnormal protection strategy.

9. The risk assessment system for the fusion of acoustic vibration and drive feedback of the height-adjustable desk as described in claim 3, characterized in that: In step S301, within each Hall analysis window, the actual speed and frequency of the motor on that side are calculated based on the Hall pulse interval. Using the motor frequency as a reference, the energy near the frequency and its harmonics is extracted from the mechanical acoustic vibration signal. The acoustic vibration RMS, peak value, impact peak value, friction frequency band energy, and envelope stability are combined to form the acoustic vibration feature set within the current Hall analysis window, which serves as the acoustic vibration feature information. When calculating the difference between the left and right sides, the Hall analysis windows on the left and right sides after the same lifting start are numbered sequentially and have the same number as the corresponding windows; or the start and end time of the Hall analysis window on one side is used as the main Hall analysis window, and the drive feedback signal and acoustic vibration characteristic information of the other side within the same time range are captured synchronously; or the timer of the control box forms a common sampling clock window as the alignment reference.

10. A method for risk assessment of the fusion of acoustic vibration and drive feedback in a height-adjustable desk, using the risk assessment system for the fusion of acoustic vibration and drive feedback in a height-adjustable desk as described in any one of claims 1-9, characterized in that: Includes the following steps: S1, take the time analysis window formed by M consecutive Hall pulses as the current Hall analysis window, and within the Hall analysis window, synchronously collect the drive feedback signals and mechanical acoustic vibration signals on the left and right sides of the lifting table, and extract the features of the mechanical acoustic vibration signals to obtain acoustic vibration feature information; S2, obtain the acoustic and vibration confidence level of the current Hall analysis window; S3, perform correlation analysis between the driving feedback signal and acoustic vibration characteristic information in the Hall analysis window, correct the weight of the acoustic vibration characteristic information in the Hall analysis window for participating in the risk score calculation with acoustic vibration confidence, and generate risk information; S4, receive risk information, which includes at least one of synchronization deviation risk, obstruction risk, mechanical anomaly risk and feedback link anomaly risk, compare each risk information with the corresponding risk threshold, and output control actions according to preset priority rules; The preset priority rules include: When all risk information is within the risk threshold, the normal path is executed, and normal acceleration / deceleration is output while continuous monitoring is maintained. When the obstruction risk exceeds the obstruction threshold, a shutdown or short-distance reversal action is output. When the synchronization deviation risk exceeds the synchronization deviation threshold, a speed reduction or synchronization compensation action is output, and a maintenance prompt or shutdown protection action is output when the synchronization deviation risk continues to rise. When the mechanical anomaly risk exceeds the mechanical anomaly threshold, a speed reduction, limited acceleration / deceleration, or maintenance prompt action is output. When the feedback link anomaly risk meets the logical judgment conditions, a low-speed stop, prompt for inspection, or recalibration action is output. When multiple risks exceed their corresponding thresholds simultaneously, control actions are selected or combined according to preset priority rules.

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