Synchronous belt tension calibration method in transit, printer and storage media

Abstract

This application relates to the field of 3D printing equipment control, and in particular to a method for in-transit calibration of synchronous belt tension for a CoreXY structure 3D printer, the printer itself, and a storage medium. Addressing the problems in existing technologies where synchronous belt tension relies on manual adjustment or static pre-tensioning during printing, and where it is difficult to identify tension drift in real time and link it with motion control, this application selects non-printing idle migration processes from the control command stream that meet certain duration conditions as calibration opportunities. During these processes, the drive motor is controlled to excite the synchronous belt, and spectral analysis is performed using the tool head accelerometer signal to obtain the dominant frequency information characterizing the tension state. Based on this, the electric tensioning component is driven to compensate, and resonance suppression parameters are updated simultaneously. This solution can achieve synchronous belt tension identification, calibration, and control parameter linkage without interrupting the printing task, improving printing accuracy, surface quality, and long-term operational stability.

Description

Technical Field

[0001] This application relates to the field of 3D printing equipment control, and more particularly to a synchronous belt tension calibration method, a printer, and a storage medium. Background Technology

[0002] CoreXY structure 3D printers utilize the combined force of A / B synchronous belts to drive the tool head, and their dynamic response characteristics are highly coupled with the tension of the synchronous belts. However, existing tension management methods mostly employ static pre-tensioning or passive elastic compensation, which are insufficient to cope with the physical changes during long-cycle printing: the physical creep and thermal elongation of the synchronous belt under thermal load and alternating stress can cause the mechanical resonance point to gradually deviate from the preset suppression frequency of the control algorithm, thereby inducing residual vibration marks on the surface of the finished product.

[0003] Therefore, how to achieve real-time sensing and accurate compensation of the tension state of the synchronous belt without interfering with the forming process is a problem that urgently needs to be solved in this field. Summary of the Invention

[0004] This application provides a synchronous belt tension calibration method, printer, and storage medium to solve the technical problem that existing 3D printers lack real-time tension sensing capabilities, making it difficult to adjust the synchronous belt tension in real time, which leads to a decrease in the accuracy of 3D printers during long-term printing tasks.

[0005] In a first aspect, this application provides a method for calibrating synchronous belt tension in transit, comprising:

[0006] Identify non-printing idle movement commands from the control command stream to be executed. If the travel time corresponding to a non-printing idle movement command exceeds a preset travel time threshold, then determine the travel time as the calibration window.

[0007] Within the calibration window, the first drive motor and the second drive motor are controlled to output anti-phase excitation signals in coordination, so that the displacement amplitude generated by the tool head is less than the preset displacement threshold, and the synchronous belt is excited to generate vibration.

[0008] Vibration signals from an accelerometer integrated into the tool head are collected, and the energy frequency of the vibration signals is extracted through spectrum analysis.

[0009] Based on the deviation between the main energy frequency and the preset target frequency, the electric tensioning component is driven to perform physical position compensation and the resonance suppression parameters in the control system are updated synchronously.

[0010] By identifying non-printing idle movement commands that meet the conditions from the control command stream to be executed and determining their corresponding travel times as calibration windows, in-transit calibration opportunities can be obtained without interfering with the normal printing process as much as possible, thus achieving online tension calibration during the printing process. Within the calibration window, the first and second drive motors are controlled to collaboratively output anti-phase excitation signals. Utilizing the mutual cancellation of the two motor signals in the resultant force direction, the synchronous belt is excited to generate micro-vibrations while ensuring that the displacement amplitude generated by the tool head is less than a preset displacement threshold (i.e., without deviating from the predetermined idle movement trajectory). This solves the problem of traditional excitation methods easily interfering with the tool head's motion accuracy. Combined with the vibration signal acquisition and energy master frequency extraction by the accelerometer integrated on the tool head, environmental noise interference can be eliminated, and the characteristic frequency representing the synchronous belt tension can be accurately locked. By driving the electric tensioning component to perform physical position compensation based on the deviation between the energy master frequency and the preset target frequency, and synchronously updating the resonance suppression parameters in the control system, deep coupling between mechanical structure reset and adaptive control algorithm is achieved. This not only eliminates the transmission error caused by the slack of the timing belt at the physical level, but also ensures that the algorithm's notch frequency is aligned with the changed physical resonance point in real time at the control level, significantly improving the printer's positioning accuracy, surface quality, and system vibration resistance under long-cycle and high-speed operating conditions.

[0011] In one possible embodiment, controlling the first drive motor and the second drive motor to collaboratively output anti-phase excitation signals includes:

[0012] The first and second drive motors are controlled to generate jitter signals with a phase difference of 180°, and the excitation amplitude of the anti-phase excitation signal is controlled by pulse width modulation so that the displacement amplitude of the tool head in the XY plane is less than a preset displacement threshold. The preset displacement threshold is determined according to the positioning accuracy of the printer or the surface quality requirements of the current printing task.

[0013] A controlled vibration source is established on the synchronous belt by using dual drive motors driven in opposite phases. A 180° phase difference is used to create a balanced excitation torque. The kinematic characteristics of the CoreXY structure allow the two excitation forces to cancel each other out at the end of the tool head, making the resultant force vector acting on the tool head approach zero. This physically avoids trajectory deviation introduced by single-sided drive. Simultaneously, PWM (Pulse Width Modulation) is used to limit and suppress excessive displacement. The output torque of the drive motors is precisely controlled by adjusting the duty cycle of the drive current, allowing the synchronous belt tension characteristics to be excited and acquired without significantly affecting the current position of the tool head. Because the displacement amplitude is limited to a preset displacement threshold, the tool head can still maintain near-in-situ operation, and vibration identification and subsequent tension compensation within the calibration window will not disrupt the continuity of the printing task. By dynamically adjusting the threshold based on the printer's positioning accuracy or the surface quality requirements of the current printing task, a deep fit between calibration accuracy and print quality is achieved: when performing printing tasks with high surface quality requirements, the threshold is reduced to ensure no texture is visible; when performing high-speed idling with high signal strength requirements, the threshold is appropriately relaxed to improve the sampling signal-to-noise ratio. This specific implementation reduces lateral disturbance of the tool head while ensuring a clear excitation response, minimizing layer texture, offset, and local surface fluctuations caused by calibration actions, thus improving the stability and forming accuracy of the 3D printer during continuous printing.

[0014] In one possible embodiment, the frequency range of the excitation pulse generated by the anti-phase excitation signal covers at least the first-order resonant frequency range of the synchronous belt under the target tension state.

[0015] By adopting this implementation method, the frequency range of the excitation signal covers at least one resonant frequency of the synchronous belt under the target tension state, ensuring that the excitation energy can be effectively coupled to the fundamental mode with the most concentrated energy of the synchronous belt, thereby obtaining a vibration characteristic signal with a high signal-to-noise ratio. Since there is a definite physical mapping relationship between the tension of the synchronous belt and the resonant frequency, locking the excitation range near the frequency corresponding to the target tension ensures that even when the tension drifts, the excitation signal can still fall within the effective response bandwidth of the synchronous belt, achieving accurate "capture" of the main frequency. On this basis, by further covering the higher-order modal response, the missed detection phenomenon caused by insufficient excitation at a single frequency point or narrow-band noise interference in the environment can be reduced, improving the completeness and robustness of the spectrum analysis. As a result, the system's judgment of tension changes is more accurate, the compensation action of the electric tensioning component is more targeted, and the resonance suppression parameters in the motion control algorithm can be kept consistent with the actual mechanical state, thereby reducing the probability of printing cracks, layer misalignment, and path deviation.

[0016] In one possible embodiment, the electrically driven tensioning assembly driving the target printer performs physical position compensation, including:

[0017] Based on the physical characteristics of the synchronous belt, the deviation between the main energy frequency and the target frequency is converted into the target displacement of the sliding block.

[0018] The number of execution pulses of the tensioning motor in the electric tensioning assembly is obtained based on the target displacement;

[0019] Based on the number of execution pulses, the drive tension motor drives the sliding seat to generate displacement through the transmission mechanism, thereby changing the center distance between the first drive motor, the second drive motor and their opposite driven wheel.

[0020] This implementation method enables the tensioning assembly to quantitatively compensate for the actual vibration state of the synchronous belt. By precisely mapping the frequency deviation to the physical displacement of the sliding seat based on the physical characteristics of the synchronous belt, and ultimately converting it into the number of execution pulses of the drive motor, micron-level adjustment of the center distance between the shafts of the first drive motor, the second drive motor, and their opposing driven pulleys is achieved. This closed-loop adjustment mechanism significantly improves the accuracy of tension recovery, eliminates the subjective errors of traditional manual adjustment, and ensures a high degree of consistency between the tension compensation process and the output of the control system. In particular, for the CoreXY structure, precise adjustment of the center distance can compensate for permanent deformation caused by long-term belt stretching, ensuring that the tension of the two synchronous belts remains highly symmetrical. Thus, tension drift caused by belt slack, thermal deformation, or long-term operation can be precisely corrected at its source, reducing trajectory errors, layering aggravation, and resonance amplification problems, significantly improving the mechanical stability, forming consistency, and motion accuracy of the printer under long-term, high-load continuous operation conditions.

[0021] In one possible embodiment, there is a preset proportional mapping relationship between the number of execution pulses and the change in the shaft center distance. The proportional mapping relationship is pre-calibrated based on the transmission ratio of the transmission mechanism and the motion trajectory of the sliding seat.

[0022] By adopting this implementation method, the electrical signal commands of the control system can be accurately converted into the physical displacement of the mechanical structure through pre-calibrating the proportional mapping relationship between the number of execution pulses and the change in shaft center distance. Since this mapping relationship comprehensively considers the transmission ratio of the transmission mechanism (such as lead screw, reduction ratio, etc.) and the actual movement trajectory of the sliding block, it effectively compensates for geometric assembly deviations in the mechanical transmission chain. This pre-calibrated mapping mechanism ensures the determinism and repeatability of the tension compensation action, enabling the control system to achieve micron-level quantitative adjustment of the synchronous belt tension. This avoids over-compensation or under-compensation caused by fuzzy transmission models, thereby significantly improving the reliability of the printer's transmission system and the consistency of print quality under complex operating conditions. Furthermore, this proportional mapping relationship provides a direct linearization control basis for the control system, simplifying the real-time computation during in-transit calibration.

[0023] In one possible embodiment, the transmission mechanism includes a worm gear drive chain or a screw drive pair;

[0024] If the transmission mechanism is a worm gear drive chain, the torque of the tensioning motor is transmitted by the worm gear drive chain, and after the physical position compensation is completed, the self-locking characteristic of the worm gear drive chain when the lead angle is less than the friction angle is used to achieve mechanical locking of the physical position of the sliding seat.

[0025] If the transmission mechanism is a screw drive pair, then the rotational motion of the tensioning motor is converted into the linear displacement of the sliding seat using the screw drive pair.

[0026] This implementation method reliably maintains the physical position after tension compensation through a specific transmission mechanism. If a worm gear transmission chain is used, its physical self-locking characteristics allow for absolute mechanical locking of the sliding seat after tension calibration. This locking eliminates the need for the tension motor to continuously output holding torque, effectively resisting the reverse tension of the synchronous belt during high-dynamic printing, preventing displacement backlash, and significantly reducing the power consumption and heat generation of the tension motor. If a screw drive pair is used, the high-precision conversion of rotary motion to linear displacement achieves smooth adjustment of the shaft center distance. Overall, this structure reduces power-off backlash, loosening caused by high-frequency vibration, and tension drift caused by long-term operation, ensuring that the transmission states of the first drive motor, the second drive motor, and the synchronous belt remain within the calibrated range. Particularly in the CoreXY structure, this locking mechanism ensures the long-term symmetry of the tension on both sides of the synchronous belt, avoiding printing geometric distortion caused by slight backlash of the tensioning mechanism on one side. This improves the motion repeatability accuracy of the CoreXY mechanism, suppresses path deviation during idle movement, and helps maintain the surface quality and interlayer consistency of the printed parts.

[0027] In one possible embodiment, the method further includes:

[0028] By monitoring the current sampling circuit of the tensioning motor, a current limiting protection action is triggered when the sliding seat moves to a preset physical stroke threshold, causing a sudden change in load.

[0029] By monitoring the operating current of the tensioning motor in real time, load anomalies caused by mechanical limit positions or accidental jamming are converted into identifiable electrical signal characteristics, thereby triggering current limiting protection in a timely manner when the sliding seat reaches a preset physical travel threshold. This detection method provides a faster response speed than traditional mechanical switches, effectively avoiding overcurrent heating of the tensioning motor in a stalled state and mechanical damage to the transmission mechanism (such as worm gears or screws). This mechanism significantly improves the safety and reliability of the tensioning assembly during physical compensation, reduces equipment downtime caused by limit collisions, and lowers long-term maintenance costs.

[0030] In one possible embodiment, synchronously updating the resonance suppression parameters in the control system includes:

[0031] After the physical position compensation is completed, the resonance suppression parameters used to control the X-axis and Y-axis motion in the control system are updated in real time to align the notch filter center frequency of the algorithm with the adjusted physical resonance frequency of the synchronous band.

[0032] With this implementation, motion control parameters can be updated in conjunction with the physical compensation results of mechanical tension. By aligning the notch filter center frequency of the algorithm with the adjusted physical resonance frequency of the synchronous band in real time, the vibration damping failure caused by the lag in control frequency after changes in mechanical state is effectively solved. Since the vibrations of the first and second drive motors in the CoreXY structure are coupled to the X and Y axes through the interlacing of the synchronous band, synchronously updating the dual-axis parameters ensures that the dynamic characteristics of the entire machine motion system remain consistent, eliminating asymmetric "ghosting" patterns induced by single-axis frequency offset. This synchronous update mechanism can significantly reduce the probability of residual vibration (vibration marks), path jitter, and layer texture deterioration during the commutation process, and improve trajectory consistency, surface quality, and forming stability under long-term high-speed printing. Because the resonance suppression frequency is dynamically aligned with the physical resonance frequency, the equipment can immediately return to the optimal vibration damping state after physical compensation without additional shutdown for frequency sweeping or manual parameter adjustment, thereby improving the printer's continuous operation capability and forming stability under complex working conditions.

[0033] In one possible embodiment, the method further includes:

[0034] The printer cavity temperature is collected in real time, and the preset target frequency is dynamically corrected based on the change in cavity temperature.

[0035] By continuously monitoring the cavity temperature and dynamically correcting the target frequency based on temperature changes, the temperature-related thermal expansion and contraction effects can be offset in advance, preventing the target frequency reference from drifting due to temperature increases or decreases, thereby reducing tension calibration errors. From a physical perspective, the Young's modulus of the synchronous belt and the geometry of the mechanical structure change with temperature, causing a shift in the natural frequency under the same tension. This solution introduces temperature compensation to ensure a constant "frequency-tension" mapping relationship under different thermal conditions. Since the synchronous belt is in a closed cavity, its physical state is directly affected by the ambient thermal field. By correcting the target frequency reference, the system can effectively prevent the system from misinterpreting frequency drops caused by thermal softening as mechanical relaxation. Because the target frequency remains matched to the actual thermal environment, the reference for subsequent physical position compensation and resonance suppression parameter updates is more stable, which helps improve the accuracy of tension calibration, consistency of motion control, and stability of forming quality during long-term printing processes.

[0036] In one possible embodiment, the method further includes:

[0037] The printer's environmental vibration level is determined by monitoring the noise floor of the accelerometer in a non-excited state. If the environmental vibration level exceeds the preset threshold, physical position compensation is suspended.

[0038] This solution establishes an environmental vibration baseline before compensation, enabling the printer to autonomously identify and defend against external interference. By monitoring the noise floor in non-vibration states, the system can effectively distinguish between "real resonance signals from the synchronous band" and "external environmental interference signals," thus automatically suppressing ineffective compensation actions in scenarios with high environmental vibration. This "sniff out the noise floor first, then perform compensation" logic ensures that physical compensation actions are always based on a reliable signal-to-noise ratio. This not only significantly reduces the impact of external mechanical disturbances on tension calibration accuracy and improves the reliability and repeatability of compensation results, but also avoids quality risks such as trajectory deviations and abnormal printing textures (e.g., vibration marks, layering faults) caused by erroneous compensation from the source. This solution is particularly suitable for industrial printing environments with multiple devices operating in parallel, complex ground vibration sources, or periodic impacts on the outside of the cavity, ensuring consistent forming quality under complex working conditions.

[0039] In one possible embodiment, the method further includes:

[0040] During the cooling phase after the printing job is completed, the automatic control tool head moves to the preset calibration position and performs a full tension scan, and performs closed-loop verification of the effect of the in-transit calibration based on the scan results.

[0041] This solution achieves secondary verification and accuracy closure of in-transit calibration results by introducing a full-volume tension scan during the cooling phase after the printing process. Due to the high temperature and high-frequency motion during printing, the synchronous belt may experience instantaneous thermal expansion or dynamic relaxation; a full-volume scan during the cooling phase can capture residual deviations caused by material thermal shrinkage, mechanical springback, or long-term stress relaxation. Standardized measurements at preset calibration positions eliminate effective span deviations caused by the randomness of the tool head position during printing, ensuring the uniqueness of the verification benchmark. This not only reduces the burden of manual inspection before the next print run but also helps maintain the long-term stability of the synchronous belt drive, thereby improving dimensional consistency, surface quality, and continuous production reliability.

[0042] In one possible embodiment, the method further includes:

[0043] Record the cumulative compensation stroke of the electric tensioning component. When the cumulative compensation stroke exceeds the preset compensation stroke threshold, output a belt replacement warning and upload a feature vector containing the device identifier of the target printer, the number of compensation pulses and the cavity temperature to the cloud diagnostic platform to receive the belt residual life evaluation report.

[0044] By continuously recording the cumulative compensation stroke, the physical compensation amount of the tensioning component can be transformed into a quantifiable lifespan criterion, thus avoiding sudden breakage or loss of precision caused by the synchronous belt continuing to serve when fatigue is nearing its limit. More importantly, by encapsulating equipment identification, compensation pulse count, and cavity temperature into feature vectors and uploading them to the cloud, a two-dimensional evaluation of mechanical and thermal stress is achieved. Since the compensation pulse count directly reflects the total mechanical displacement performed to maintain tension, its value is positively correlated with the creep and wear of the synchronous belt. After receiving the feature vectors, the cloud diagnostic platform can combine historical big data to make individualized and accurate predictions of the belt's aging status, transforming replacement warnings from experience-based judgments to data-driven predictive maintenance. This reduces the risk of printing misalignment, forming scrap, and unplanned downtime caused by synchronous belt failure, thereby improving the operational efficiency of the equipment cluster.

[0045] In one possible embodiment, the method further includes:

[0046] The tensioning motor is controlled to operate in a micro-step drive mode with a minimum of 16 microsteps.

[0047] The fixed-frequency interference caused by the cooling fan in the accelerometer signal is filtered out by a digital filtering module.

[0048] By combining high-resolution drive with targeted digital filtering, the microscopic precision of tension adjustment and the reliability of signal processing are significantly improved. The electric tensioning assembly operates in a micro-step mode with at least 16 microsteps, refining the stepping motion of the tensioning motor into smaller angular displacements. This achieves sub-micron-level step control of the shaft center distance at the physical level, reducing the impact of mechanical backlash and stepping pulsation on tension adjustment accuracy and avoiding overshoot during adjustment. Simultaneously, the digital filtering module eliminates fixed-frequency interference caused by the cooling fan, removing "false characteristic peaks" in the spectrum analysis and ensuring that the extracted energy frequency truly reflects the physical tension state of the synchronous belt. Since the cooling fan is typically located in the compact space of the tool head along with the accelerometer, its high-frequency vibration can easily mask the low-frequency resonance of the synchronous belt. This solution ensures the signal-to-noise ratio during in-transit calibration through frequency domain "denoising." Therefore, the equipment maintains extremely high frequency recognition accuracy and tension control stability even under continuous operation in a high-temperature, enclosed cavity with strong air cooling.

[0049] Secondly, this application provides a printer, comprising:

[0050] The motion actuator includes a first drive motor, a second drive motor, a synchronous belt, and a tool head integrating an acceleration sensor;

[0051] An electric tensioning assembly includes a tensioning motor, a transmission mechanism coupled to the output end of the tensioning motor, and a sliding seat driven by the transmission mechanism. The sliding seat is connected to a first drive motor, a second drive motor, or a driven idler wheel and is used to change the tension of the synchronous belt by displacement.

[0052] The control system is electrically connected to the acceleration sensor, the first drive motor, the second drive motor and the tension motor respectively, and the control system is configured to perform the method as described in any of the first aspects.

[0053] The aforementioned printer achieves closed-loop control of synchronous belt tension during transit by integrating an accelerometer sensor into the tool head and constructing a vibration-sampling-execution hardware link under unified control of the control system. This architecture utilizes the tool head as a natural vibration sampling point to directly acquire the most accurate physical response of the synchronous belt. Simultaneously, through the mechanical coupling of the electric tensioning component with the first drive motor, second drive motor, or driven wheel, the device possesses the ability to automatically respond to tension drift without disassembly or manual intervention. This high degree of hardware and software synergy effectively solves the problem of tension inaccuracy in printers under high-temperature, long-term operation, and frequent reversing conditions, significantly reducing the risks of path errors, vibration marks, and surface defects, ensuring consistent dimensional accuracy and surface quality in batch production. Furthermore, by integrating the tensioning motor with the transmission mechanism, digital quantitative control of tension adjustment is achieved, replacing traditional manual experience-based adjustments.

[0054] Thirdly, this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the method of any one of the first aspects.

[0055] The synchronous belt tension in-transit calibration method, printer, and storage medium provided in this application identify non-printing idle movement commands that meet the conditions from the control command stream to be executed and determine their corresponding travel time as the calibration window. This allows for in-transit calibration opportunities without interfering with the normal printing process, thereby achieving online tension calibration during printing. By controlling the first and second drive motors to collaboratively output anti-phase excitation signals to excite synchronous belt vibration within the calibration window, and by acquiring the vibration signal from the accelerometer integrated on the tool head in real time and extracting the energy main frequency, the actual vibration state of the current synchronous belt can be characterized more accurately, thus providing a basis for judging tension deviation. By driving the electric tensioning component to perform physical position compensation based on the deviation between the energy main frequency and the preset target frequency, and simultaneously updating the resonance suppression parameters in the motion control algorithm, the mechanical tension correction of the synchronous belt and adaptive matching of control parameters can be completed simultaneously, thereby improving the positioning accuracy, printing stability, and operational reliability of the printer under long-cycle, high-speed, or high-temperature conditions. Attached Figure Description

[0056] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0057] Figure 1 A schematic flowchart illustrating a synchronous belt tension calibration method in transit, provided for an embodiment of this application;

[0058] Figure 2 This is a schematic diagram of the structure of a printer provided in an embodiment of this application.

[0059] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0060] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0061] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, storage, use, processing, transmission, provision, disclosure, and application of the relevant data all comply with the relevant laws, regulations, and standards of the relevant countries and regions, have taken necessary confidentiality measures, do not violate public order and good morals, and provide corresponding operation access points for users to choose to authorize or refuse.

[0062] Furthermore, the technical solution involved in this application, which involves big data analysis of user information (including but not limited to personal biometrics, identity data, consumption data, asset data, electronic terminal operation data, etc.) and the use of artificial intelligence technology for automated decision-making, and makes decisions that have a significant impact on personal rights based on the results of automated decision-making, provides users with corresponding operation entry points for users to choose to agree to or reject the results of automated decision-making; if the user chooses to reject, the process will proceed to the expert decision-making process.

[0063] It should be noted that this application relates to the field of additive manufacturing technology, specifically to a synchronous belt tension in-transit calibration method, printer and storage medium, which can be used in the field of 3D printing equipment control, or in any field other than 3D printing equipment control. The application fields of the synchronous belt tension in-transit calibration method, printer and storage medium in this application are not limited.

[0064] With the popularization of additive manufacturing technology, CoreXY structural 3D printers, a type of consumer additive manufacturing equipment, are increasingly being used in scenarios such as high-precision figurines, architectural models, medical auxiliary components, automotive modification parts, and small-batch tooling fixtures. These scenarios have extremely high requirements for the dimensional accuracy, interlayer bonding quality, and surface quality of the formed parts.

[0065] In such applications, a printer typically includes a printing head that performs the printing task, a drive motor that drives the printing head to move at high speed in the XY plane, a synchronous belt drive mechanism connected to the drive motor, a control unit that receives and parses the control command stream, and a temperature control chamber, a material supply unit, and a motion control algorithm module that work in conjunction with the printing task. In actual production, the control command stream is usually generated by the slicing software and continuously sent to the equipment, including both the extrusion printing path and non-printing idle movement paths such as interlayer transposition, avoidance, and cross-zone movement.

[0066] Because the CoreXY mechanism relies on two synchronous belts to transmit motion, the tool head's trajectory accuracy, reversing response, dynamic stability during acceleration and deceleration, and final forming quality are all closely related to the tension of the synchronous belts. Especially under conditions such as long-term continuous operation, high-temperature enclosed chambers, high-speed reciprocating motion, and frequent start-stop reversals, the synchronous belts not only perform the transmission function but also directly affect the overall machine's resonance characteristics and control parameter matching. For consumer users, due to a lack of professional mechanical maintenance experience and expensive external testing equipment, monitoring, maintaining, and calibrating the synchronous belt tension has become an unavoidable critical step in achieving high consistency in the operation of such equipment. Any deviation in synchronous belt tension can gradually amplify into tool head path errors, layer deterioration, increased local vibration marks, and even finished product scrap. Therefore, this technical field naturally has a real need for continuous monitoring and intervention of the tension state during the printing process.

[0067] In existing technologies, the management of synchronous belt tension in consumer-grade or semi-professional CoreXY structure 3D printers is mainly based on two approaches: stop-and-adjust and static pre-tensioning. A common approach involves manually resetting the synchronous belt tension after an anomaly is detected by adjusting bolts, eccentric wheels, or mounting bracket positions. Another approach involves introducing elastic components for passive compensation, such as using springs to provide a nearly constant pre-tension force. While these approaches are structurally simple, they share a common problem: their understanding of synchronous belt tension remains at the level of pre-setting and post-printing correction, lacking real-time sensing capabilities during the printing process.

[0068] Once a printing job begins, especially in high-temperature chambers or long-cycle jobs, tension drift in the synchronous belt caused by thermal expansion, material fatigue, and mechanical stress relaxation often cannot be quantified and identified in a timely manner. Operators can only address these issues based on experience after quality problems such as layer misalignment, edge vibrations, or so-called "ghosting" occur. Furthermore, traditional static tensioning methods struggle to handle dynamically changing conditions. Frequent motor reversals and chamber temperature fluctuations can alter the overall machine's resonance characteristics, and fixed elastic components, due to their non-adjustable stiffness, may introduce new vibration sources during high-speed movement. More critically, even with mechanical tension adjustments, the motion control algorithm parameters in the control system (such as the Input Shaper frequency) often fail to synchronize with the new mechanical resonance state, leading to a disconnect between the physical state and control parameters. In other words, current technology not only struggles to continuously and quantitatively monitor synchronous belt tension during printing but also fails to establish a linkage between tension changes and motion control, thus failing to meet the stability requirements of long-duration, high-precision printing jobs.

[0069] Therefore, how to achieve on-the-go identification, real-time analysis, and timely compensation of synchronous belt tension during the execution of a printing task has become a technical problem that urgently needs to be solved in this field.

[0070] The synchronous belt tension calibration method, printer, and storage medium provided in this application identify non-printing idle movement commands from the control command stream to be executed. If the travel time corresponding to the non-printing idle movement command exceeds a preset travel time threshold, the travel time is determined as a calibration window. Within the calibration window, the first drive motor and the second drive motor are controlled to output anti-phase excitation signals in coordination, so that the displacement amplitude generated by the tool head is less than the preset displacement threshold, and the synchronous belt is excited to vibrate. The vibration signal of the accelerometer integrated on the tool head is collected, and the energy main frequency of the vibration signal is extracted through spectrum analysis. Based on the deviation between the energy main frequency and the preset target frequency, the electric tensioning component is driven to perform physical position compensation, and the resonance suppression parameters in the control system are updated synchronously.

[0071] This method identifies non-printing idle movement commands that meet certain conditions from the control command stream to be executed and determines their corresponding travel time as a calibration window. This allows for in-transit calibration opportunities without significantly interfering with the normal printing process, enabling online tension calibration during printing. Within the calibration window, the first and second drive motors are controlled to collaboratively output anti-phase excitation signals. The mutual cancellation of the two drive motor signals in the resultant force direction excites the synchronous belt to generate micro-vibrations while ensuring the displacement amplitude of the tool head is less than a preset displacement threshold (i.e., without deviating from the predetermined idle movement trajectory). This solves the problem of traditional excitation methods easily interfering with the tool head's motion accuracy. Combined with an accelerometer integrated on the tool head to collect vibration signals and extract the energy master frequency, environmental noise interference can be eliminated, accurately locking the characteristic frequency representing the synchronous belt tension. By driving the electric tensioning component to perform physical position compensation based on the deviation between the energy master frequency and the preset target frequency, and simultaneously updating the resonance suppression parameters in the control system, a deep coupling between mechanical structure reset and adaptive control algorithm is achieved. This not only eliminates the transmission error caused by the slack of the timing belt at the physical level, but also ensures that the algorithm's notch frequency is aligned with the changed physical resonance point in real time at the control level, significantly improving the printer's positioning accuracy, surface quality, and system vibration resistance under long-cycle and high-speed operating conditions.

[0072] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0073] Figure 1 This is a flowchart illustrating a synchronous belt tension calibration method in transit, as provided in an embodiment of this application. Figure 1 As shown, the method includes:

[0074] S101: Identify non-printing idle movement instructions from the control instruction stream to be executed. If the travel time corresponding to the non-printing idle movement instruction exceeds the preset travel time threshold, then determine the travel time as the calibration window.

[0075] In this embodiment, the control command flow can be a continuous sequence of motion commands generated by the slicing software and sent to the 3D printer control system. This sequence describes the tool head's trajectory, speed, acceleration, extrusion state, and layer switching behavior during the printing task. Non-printing idle movement commands can be understood as motion commands that do not accompany material extrusion. During execution, the tool head undergoes spatial displacement, but the material supply unit remains in a non-discharging or stopped-extrusion state. Typical examples include interlayer relocation, avoidance movements, cross-zone transfers, and path segments moving from one forming area to another. The stroke time can represent the duration required for the tool head to execute a non-printing idle movement segment. This duration can be calculated by comprehensively considering the path length, target speed, acceleration / deceleration constraints, and the interpolation strategy of the control system. The preset stroke time threshold can be the minimum available calibration time set internally by the control system to ensure sufficient time for excitation, sampling, analysis, and compensation without affecting the normal printing cycle. The calibration window can be understood as the time interval for performing synchronous belt tension detection and calibration that has been identified and defined. Its start and end times can correspond to the start and end times of a certain non-printing idle shift segment, and the front and rear boundaries can also be finely adjusted according to the control strategy of the control system to balance safety and processing integrity.

[0076] In practical implementation, the main processor in the control system pre-reads the control instruction stream buffer to be executed, parses multiple motion instructions to be executed, and identifies instructions indicating rapid movement, non-extrusion movement, or movement determined to be in an idle state based on extrusion amount. For example, in one possible embodiment, the control system can identify G0 (Rapid Positioning) instructions in G-code (Geometric Code), or identify movement instructions that, although using G1 (Linear Interpolation) format, do not show positive feed of the extrusion axis parameters. It then combines this information with the current print status register to determine whether the movement segment belongs to a non-printing idle movement. For the identified idle movement segment, the control system reads its starting coordinates, ending coordinates, set feed speed, current acceleration limit, and kinematic calculation results, and calculates the theoretical travel time according to the movement distance and speed curve. When the idle movement segment includes acceleration, constant speed, and deceleration segments, the time consumed in each segment can be calculated separately and summed to obtain a time estimate closer to the actual execution result. If the printer is currently operating within a high-temperature, enclosed cavity, the control system can further refine the theoretical travel time by incorporating recent execution logs, including average response latency, microstepping configuration, and speed look-ahead compensation status, thereby improving the accuracy of the calibration window determination. Furthermore, the preset travel time threshold should be at least greater than the sum of one complete frequency sweep cycle of the excitation signal and the accelerometer data sampling cycle to ensure complete frequency sniffing within a single window.

[0077] In another possible implementation, the identification of the calibration window is not limited to a single idle movement command, but can merge and analyze multiple consecutive adjacent non-printing idle movement segments. When there is no extrusion action between adjacent path segments, and the tool head movement direction switching amplitude is small and control idle time is continuous, the control system can merge multiple short idle movement segments into a composite time interval and compare the total duration of the merged segment with a preset travel time threshold. If the total duration meets the requirement, the composite time interval is determined as the calibration window. This avoids the inability to trigger calibration due to a single idle movement command being too short, while improving the utilization rate of calibration opportunities. Furthermore, the control system can also combine information such as the non-forming area movement segment during layer switching, the short pause segment caused by path optimization, and the transition movement segment while waiting for temperature control to stabilize to establish a candidate set of calibration opportunities. Then, based on the importance of the current printing layer, the expected location of vibration-sensitive areas, and the safe distance between the tool head and the workpiece, the candidate set is screened to ensure that subsequent calibration actions will not interfere with key contours, thin-walled structures, or overhanging areas during forming.

[0078] This step also requires configuring basic parameters related to time threshold determination. For example, the preset travel time threshold can be obtained from the equipment's factory calibration or adjusted online based on the control system performance, sampling frequency, and the speed of the compensation mechanism. For instance, when establishing a stable vibration state requires 10 to 30 milliseconds, vibration sampling requires 20 to 80 milliseconds, spectrum analysis and control decision-making require 5 to 20 milliseconds, and the tensioning component requires 30 to 100 milliseconds to perform minimum step compensation, the controller can sum the durations of each of these processing stages and add a safety margin to form the actual threshold used. This safety margin is used to absorb communication delays, thermal drift effects, and motion execution errors, preventing calibration actions from encroaching on printing time. Based on the above processing, this step, by pre-reading, classifying, and filtering the control command flow, transforms the non-printing periods originally scattered throughout the printing task into an adjustable calibration window, allowing synchronous belt tension detection to be embedded within the normal production process instead of relying on downtime maintenance. For CoreXY structure 3D printers, this processing method can dynamically determine the timing of tension calibration without interrupting the printing task, thereby alleviating the problem that tension drift caused by long-term operation, high-temperature environment and frequent reversal cannot be detected in time.

[0079] In one example, the control system runs an instruction prefetch queue in the background. When a G0 instruction (idle movement instruction) is prefetched, and the travel time corresponding to the Euclidean distance between the start and end points exceeds 150ms, the control system marks it as a "calibration window." During the first 10% of the idle movement (when the tool head has completed acceleration), the control system controls the first and second drive motors to collaboratively output anti-phase excitation signals (e.g., generating a small jitter signal with a 180° phase difference). At this time, the control system determines a preset displacement threshold of 0.05mm based on the surface quality requirements of the current printing task (e.g., high-precision model printing), and controls the excitation amplitude of the anti-phase excitation signal through pulse width modulation, so that the displacement amplitude of the tool head in the XY plane caused by the jitter signal is controlled within 0.05mm. Since the nozzle is not spouting filament at this time, and the tool head is in motion, the momentum generated by the tool head can trigger synchronous belt excitation. An accelerometer mounted on the tool head collects the free vibration waveform of the tool head at this time. In this way, the system completes real-time parameter sniffing without being aware of the process.

[0080] S102: Within the calibration window, control the first drive motor and the second drive motor to output anti-phase excitation signals in coordination, so that the displacement amplitude generated by the tool head is less than the preset displacement threshold, and excite the synchronous belt to generate vibration.

[0081] In this embodiment, the first drive motor and the second drive motor are connected to a synchronous belt. The first drive motor and the second drive motor can be two independent servo motors or stepper motors in the CoreXY mechanism. They are coupled to the tool head motion mechanism through a synchronous belt transmission path and achieve planar motion in the X and Y directions through combined drive.

[0082] Anti-phase excitation signals can be understood as drive signals with opposite phases, having a phase difference of approximately 180° between the two signals. This results in two drive motors mechanically generating symmetrical micro-amplitude excitation. The vibration frequency signal generated by the synchronous belt can represent the dynamic response information of the synchronous belt under excitation. This information can be measured by an accelerometer integrated into the tool head, or by estimating the back electromotive force of the drive motor, measuring with an additional vibration sensor, or by indirect measurement methods related to the tool head's structural response. Real-time acquisition refers to continuously acquiring vibration-related data at a preset sampling period during the calibration window, rather than reading it back all at once after the window ends. This allows the control system to promptly determine whether the excitation is sufficient, whether the signal is valid, and whether repeated excitation is necessary based on the current response state.

[0083] In specific implementation, after the control system confirms entry into the calibration window, unnecessary high-frequency motion correction tasks within that window are paused, and excitation parameters, including excitation start time, pulse duration, amplitude upper limit, phase relationship, and scanning frequency band, are sent to the first and second drive motors respectively. For example, in one possible embodiment, the two drive motors receive current pulse sequences or micro-displacement jitter sequences with a phase difference of 180°, wherein the first drive motor outputs a positive-negative periodic change, and the second drive motor outputs a corresponding negative-positive periodic change, so that the synchronous belt coupled to it is subjected to alternating stretching and releasing effects. Based on the kinematic characteristics of the CoreXY structure, the displacement of the tool head in the X and Y directions depends on the vector sum and vector difference of the displacements of the first and second drive motors, respectively. By controlling the first and second drive motors to output excitation signals with a phase difference of 180° and equal amplitude, the resultant force acting on the tool head cancels each other out in the predetermined motion direction, thereby limiting the displacement amplitude of the tool head within a preset displacement threshold.

[0084] To achieve this, the control system determines a preset displacement threshold based on the printer's positioning accuracy requirements or the surface quality requirements of the current printing task. It then controls the amplitude of the inverse excitation signal using pulse width modulation (PWM) to keep the displacement amplitude of the tool head in the XY plane caused by the excitation within the preset displacement threshold. Here, "keeping the displacement amplitude of the tool head less than the preset displacement threshold" means that the instantaneous displacement amplitude of the tool head during excitation is less than the printer's minimum positioning resolution, or less than 1 / 10 of the current print nozzle diameter. This ensures that the excitation operation does not leave perceptible pauses or positional shifts on the printed surface. For example, for high-precision printing tasks, the preset displacement threshold can be set to 0.05mm, meaning the instantaneous displacement of the tool head is controlled within 0.05mm, or within the allowable error range of the current process. For printing tasks that require stricter positional stability, the current position can be locked before excitation and a micro-displacement compensation subroutine can be enabled. By recording the small displacement deviation during excitation and sending a reverse compensation pulse after excitation, the tool head can quickly return to the original interpolation trajectory, thereby eliminating the residual effect of excitation on path accuracy.

[0085] The frequency setting of the anti-phase excitation signal can be adjusted according to the current structural state of the equipment. For example, in one possible embodiment, the control system retrieves historical calibration records, equipment model parameters, and ambient temperature information to estimate the resonant frequency range of the synchronous belt. The frequency range of the excitation pulse generated by the anti-phase excitation signal at least includes the first-order resonant frequency (fundamental frequency) of the synchronous belt under the target tension state, and preferably covers the first to third-order resonant frequency range of the synchronous belt. According to the string vibration frequency formula:

[0086]

[0087] Where T is the tension, L is the belt length, and ρ is the linear density. The resonant frequency of the synchronous belt is proportional to the square root of the tension; therefore, the current physical tension state can be inversely calculated by extracting the dominant energy frequency. Then, frequency sweep excitation is performed within this range. The frequency sweep process can be linear or segmented. For example, the control system first excites at a lower frequency for 10 to 20 milliseconds, then gradually increases the frequency in fixed steps, maintaining several vibration cycles at each frequency point to collect response amplitudes at different frequency points and determine the region where the dominant energy frequency is located. When it is necessary to shorten the calibration time, narrow-band excitation can also be performed directly around the dominant frequency obtained from the previous calibration to quickly obtain the updated frequency response. If the equipment is in a high-temperature cavity, considering that the elastic modulus of the synchronous belt material changes with temperature, the control system can also perform temperature compensation on the excitation frequency band according to the cavity temperature, ensuring that the scanning range always covers the region near the true resonance point.

[0088] Regarding the acquisition path of the vibration frequency signal, one possible implementation is to use an accelerometer integrated into the tool head to acquire the vibration signal; another possible implementation is to use the current response and back electromotive force change inside the drive motor driver to calculate the belt vibration frequency; alternatively, a vibration pickup unit can be set at the tension end of the synchronous belt, the guide wheel bracket, or near the frame to directly sense the structural micro-vibrations caused by the belt vibration and transmit them to the control system through an analog-to-digital conversion channel. Regardless of the acquisition path used, the control system can timestamp the acquired raw signal and associate it with the current excitation frequency and tool head attitude state to form the data frame required for subsequent spectrum analysis. Since there is a stable mechanical coupling relationship between the synchronous belt and the first and second drive motors, reverse-phase excitation can directly establish a measurable vibration state using the original transmission system without adding an additional complex excitation mechanism, thereby achieving on-the-go sensing of synchronous belt tension changes.

[0089] In one example, in the practical application of the CoreXY structure, excessive excitation displacement can directly interfere with the positioning accuracy of the tool head in the XY plane. In this embodiment, the control system uses PWM to control the first and second drive motors to output a set of sinusoidal current sequences. Table 1 is a comparison table of experimental data after using PWM to control the first and second drive motors to output a set of sinusoidal current sequences and the control group without using PWM.

[0090] Table 1. Comparison of the relationship between excitation amplitude, signal recognition accuracy, and positioning accuracy.

[0091]

[0092] As shown in Table 1, when the displacement is controlled within a preset displacement threshold (e.g., 0.05 mm, which is 0.04 mm in this embodiment), although the signal-to-noise ratio of the accelerometer decreases slightly, it is still sufficient to extract the main energy frequency through the FFT algorithm. The deformation at this amplitude is mainly absorbed by the elastic deformation of the synchronous belt, and will not cause step displacement between the tool head slider and the guide rail, thus ensuring that "in-transit calibration" will not have any visually visible geometric interference with the current printing layer.

[0093] S103: Collects vibration signals from the accelerometer integrated on the tool head and extracts the energy frequency of the vibration signal through spectrum analysis.

[0094] In this embodiment, an accelerometer is integrated into the printer's tool head. The accelerometer can be a single-axis, dual-axis, or triaxial microelectromechanical (MEMS) accelerometer, and its mounting location can be the tool head body, printhead bracket, hot-end mounting plate, slider rigidly connected to the tool head, or other structural components capable of accurately reflecting the vibration transmission response of the synchronous belt. The vibration signal can be a time-domain voltage signal or a digital sampling sequence output by the accelerometer, used to characterize the minute vibration response experienced by the tool head during excitation.

[0095] Spectrum analysis can be understood as the process of converting time-domain vibration signals to the frequency domain to identify the energy distribution corresponding to each frequency component. The dominant energy frequency refers to the frequency component with the highest energy proportion or the most significant peak value in the vibration signal after filtering, window function processing, and frequency domain calculation. This frequency corresponds to the tension state of the synchronous belt. Since the higher the tension of the synchronous belt, the higher its natural frequency is usually, extracting the dominant energy frequency can map the tension change, which is difficult to measure directly, into a quantifiable frequency offset.

[0096] In practice, before the S102 excitation begins or at the start of synchronization, the control system initiates data acquisition from the tool head accelerometer, continuously reading the sensor output according to a predefined sampling rate. The sampling rate must be at least twice the target analysis frequency band (i.e., satisfying the Nyquist sampling law). If harmonic identification and frequency resolution requirements are considered, a higher sampling rate can be used. During acquisition, the control system buffers the raw time-domain data and appends metadata such as the current window number, excitation frequency, cavity temperature, tool head position, and driver status for subsequent analysis and correlation judgment. Since the tool head itself has motion acceleration during idle movement, the control system needs to separate the micro-vibration signal from the strong signal of the overall tool head motion trajectory through high-pass filtering or time-domain subtraction.

[0097] Because the printing equipment contains interference sources such as fan rotation, stepper drive current ripple, inherent frame vibration, and environmental ground disturbances, the control system can preprocess the time-domain data after acquisition. For example, in one possible embodiment, the control system first performs DC component removal and bandpass filtering using a digital filtering module, retaining only the frequency band signal where resonance may occur in the synchronous band. Then, a Hanning window, Blackman window, or other window functions are used to mitigate spectral leakage caused by truncation. Finally, a Fast Fourier Transform (FFT) is performed on the processed data sequence to obtain the frequency domain amplitude spectrum or power spectral density distribution. Specifically, the control system uses a digital filtering module to filter out fixed-band interference caused by the cooling fan in the accelerometer signal. This fixed-band interference is typically preset based on the rated speed of the cooling fan and the passing frequency of its blades to ensure that the extracted signal is mainly generated by synchronous band excitation.

[0098] After obtaining the frequency domain results, the control system retrieves the peak points within the frequency band and extracts the energy master frequency based on preset judgment rules. The energy master frequency physically corresponds to the fundamental frequency (first-order natural frequency) of the synchronous band under the current tension. For example, in one possible embodiment, the frequency point with the largest amplitude in the power spectrum is directly determined as the energy master frequency; in another possible embodiment, to avoid misjudgment caused by occasional noise spikes, energy integration can be performed on adjacent frequency points, and the center frequency with the largest total energy in the frequency band can be selected as the energy master frequency. If the equipment exhibits a situation where the frame structure resonance peak is adjacent to the synchronous band resonance peak under certain postures, the control system can also call upon the historical resonance fingerprint database to compare the peak width, harmonic distribution, phase characteristics, and temperature sensitivity of different frequency peaks, eliminating interference peaks more likely to originate from fans, guide rails, housing panels, or the inherent modes of the frame. To improve recognition robustness, the spectral results obtained from multiple repeated excitations can be averaged, or adaptive filtering, Kalman filtering, multi-channel data fusion, and other methods can be used to improve the stability of master frequency extraction. In addition, the control system also determines the ambient vibration level of the printer by monitoring the noise floor of the accelerometer in a non-excited state. If the ambient vibration level exceeds the preset threshold (such as detecting strong external vibration or ground impact), the current signal is determined to be unreliable, and subsequent physical position compensation actions are suspended to prevent miscalibration.

[0099] If the equipment is equipped with a cavity temperature sensor, an environmental vibration sensor, or a motor status monitoring module, the control system can also introduce temperature correction and interference suppression during the spectrum analysis stage. Specifically, an increase in cavity temperature may cause a decrease in the elasticity of the timing belt material, resulting in a slight change in the natural frequency under the same tension. Therefore, the control system can dynamically correct the preset target frequency according to the temperature drift correction model, or convert the measured main frequency to the equivalent frequency value under standard temperature conditions. The background vibration collected by the environmental vibration sensor can be used as a reference signal input to the noise reduction algorithm to separate external disturbances from the timing belt excitation response. The tool head integrated accelerometer has the advantages of simple layout, short response path, and high coupling with the actual printing motion state, which can better reflect the comprehensive dynamic characteristics of the timing belt vibration after it is transmitted to the end effector through the transmission chain. Based on the above analysis, this step establishes a quantitative mechanism for inferring the timing belt tension state from the mechanical dynamic response by performing spectrum processing on the tool head vibration response. Compared with the method of simply relying on experience to judge the changes in the finished product texture, it can detect tension drift earlier and more objectively, and provide accurate basis for subsequent closed-loop compensation.

[0100] In one example, the elastic modulus of the timing belt differs significantly between a cavity temperature of 60°C and a room temperature of 25°C. The control system uses a cavity temperature sensor to collect the printer cavity temperature in real time and dynamically corrects the preset target frequency based on the temperature change. For example, experiments show that a 10°C increase in temperature causes the timing belt to soften due to heat, resulting in a natural frequency drop of approximately 1.2Hz. The control system automatically adjusts the target frequency reference using a temperature drift meter to prevent the system from misinterpreting this as "belt slack" and performing excessive physical tension, thus avoiding the risk of "positive feedback failure" caused by accelerated belt aging due to excessive tension.

[0101] S104: Based on the deviation between the main energy frequency and the preset target frequency, drive the electric tensioning component to perform physical position compensation and synchronously update the resonance suppression parameters in the control system.

[0102] In this embodiment, the preset target frequency can be the synchronous belt reference frequency obtained through calibration under standard assembly conditions, reference temperature conditions, and target tension values, or it can be dynamically generated based on the printer model, synchronous belt specifications, pulley pitch, transmission path length, and cavity temperature corresponding to the correction model. The deviation can be expressed as the frequency difference obtained by subtracting the preset target frequency from the currently measured energy main frequency, or it can be expressed as a frequency ratio deviation or normalized error value.

[0103] The electric tensioning assembly may include a tensioning motor, a transmission mechanism (such as a drive chain), a sliding seat, a guide rail, a fixed seat, and an adjustment mechanism connected to the tensioning end of the synchronous belt. The tensioning motor receives compensation control commands from the control system, the transmission mechanism converts the tensioning motor torque into linear displacement, and the sliding seat increases or decreases the synchronous belt tension by changing the center distance of the pulleys, the position of the tensioning block, or the position of the pressure member. Resonance suppression parameters can be the notch filter center frequency, bandwidth parameters, input shaping frequency, vibration compensation parameters in acceleration / deceleration feedforward, or target values ​​used in the driver's vibration suppression register in the motion control algorithm. Their function is to ensure that the control algorithm maintains consistency with the resonance characteristics of the current mechanical system.

[0104] In practical implementation, after obtaining the main energy frequency, the control system first calculates the frequency deviation based on the preset target frequency and determines whether the deviation exceeds the allowable bandwidth. If the deviation is within the allowable range, it indicates that the current synchronous belt tension still meets the printing requirements, and the control system can perform only parameter fine-tuning or directly end the calibration. If the deviation exceeds the allowable range, the compensation process begins. For example, in one possible embodiment, the control system pre-stores a tension-frequency-displacement mapping table, established through factory calibration, describing the main frequency variation relationship of the synchronous belt at different tension positions. The control system queries the mapping table based on the difference between the current main frequency and the target frequency, calculates the displacement to be compensated, and then, combined with the tension motor screw lead, worm gear transmission ratio, or step angle subdivision parameters, converts the displacement into the number of step pulses the tension motor should execute or the servo target position value. To ensure execution accuracy, the control system controls the tension motor to operate in a micro-step drive mode with at least 16 subdivisions to achieve micron-level tension stroke control. If the current main frequency is lower than the target frequency, it indicates that the tension is too low. The control system will then drive the tensioning component to move in the direction of increasing the center distance or increasing the clamping amount. If the current main frequency is higher than the target frequency, reverse compensation will be performed to release some tension, thereby avoiding over-tensioning that could increase the bearing load or transmission resistance.

[0105] In practice, the control system calculates the required physical compensation based on the deviation between the energy main frequency and the preset target frequency. In one example, when the control system detects the measured energy main frequency... Below the target frequency At that time, the following mechanism transition is performed:

[0106] Calculation of tension change:

[0107]

[0108] The formula for calculating tension deviation is derived as follows:

[0109] .

[0110] Physical displacement conversion: Based on the physical characteristic parameters of the synchronous belt (such as cross-sectional area A and elastic modulus E), according to the physical formula... The required stretch length of the timing belt is calculated. .

[0111] Pulse output: This is converted to the number of pulses N of the tensioning motor in the electric tensioning assembly. The calculation formula is:

[0112]

[0113] Where S is the target displacement of the sliding block (corresponding to...) ), The step angle of the tensioning motor, Let be the lead of the transmission mechanism, and i be the transmission ratio. By... Divide by the movement resolution per step of the tensioning mechanism (e.g., 0.002 mm / step) to obtain the precise number of steps required for the tensioning motor to execute.

[0114] In practical applications, to improve the computational response speed of the control system, the corresponding relationships derived from the above formulas can be pre-stored as a tension-displacement mapping table. The tension-displacement mapping table includes mapping tables calibrated for specific materials of the timing belt (such as glass fiber reinforced rubber belts). The control system identifies the current main frequency. Compared with the target benchmark deviation Then, the number of step pulses N is directly found through a piecewise linear interpolation mapping table, which avoids the problem of processor overload under high-frequency printing tasks and achieves near real-time performance of the compensation action.

[0115] At the mechanical actuation level, the electric tensioning assembly can achieve position adjustment using a worm gear, lead screw slide, eccentric cam drive, or rack and pinion structure. For example, in one possible embodiment, the tensioning motor drives a sliding block along a guide rail via a worm gear transmission chain. A synchronous belt guide wheel or tensioning wheel is mounted on the sliding block, and its position change alters the synchronous belt wrap angle and effective tension length, thereby changing the center distance between the shafts of the first drive motor, the second drive motor, and their opposing driven wheels. The worm gear transmission chain has a self-locking characteristic, maintaining a stable position without continuous power supply after compensation, thus suppressing tension retraction caused by repeated starts and stops and high-frequency vibrations. After issuing a compensation command, the control system can monitor the encoder feedback, current changes, or limit switch status of the tensioning motor to confirm that the tensioning assembly has reached the target position. Simultaneously, by monitoring the current sampling circuit of the tensioning motor, when the sliding block moves to a preset physical travel threshold causing a sudden load change (such as reaching a mechanical limit), a current-limiting protection action is triggered to prevent motor burnout or damage to transmission components. If obstruction, overtravel, or execution failure is detected, compensation can be terminated and a fault log recorded. To avoid excessive compensation at once, the control system can also break down the total compensation into multiple micro-step actions, and quickly sample the vibration signal again after each action until the main frequency approaches the target value, thus forming fine-grained closed-loop control.

[0116] Synchronously updating the resonance suppression parameters in the control system is another crucial step in this process. Since changes in the synchronous belt tension not only affect transmission stiffness but also alter the overall resonance point position, even if the mechanical tension is corrected, ghosting, vibration patterns, or commutation overshoot may still occur during high-speed printing if the motion control algorithm continues to use the old parameters. Therefore, while performing physical compensation calculations, the control system writes the updated target frequency into the relevant parameter table of the motion control algorithm. For example, if the control system uses notch filtering to suppress a major resonance point, the notch filter center frequency of the algorithm is aligned with the adjusted physical resonance frequency of the synchronous belt; if the control system uses input shaping technology to reduce residual vibration, the shaper period parameters and pulse interval can be reset accordingly. Through this hardware-software linkage, the mechanical state and the algorithm state can remain consistent, thereby improving dynamic stability during acceleration and deceleration.

[0117] In one example, the electrically operated tensioning assembly is mounted at the rear frame corner of a CoreXY printer. A tensioning stepper motor is connected via a coupling to a worm gear with a lead of 1.5 mm, which drives a meshing worm wheel (gear ratio i: 1:40). A lead screw is fixed to the center of the worm wheel, driving a sliding block to move. Because the lead angle γ of the worm gear and worm wheel is smaller than the equivalent friction angle between the materials... (usually designed as) The mechanism satisfies the self-locking condition. When the synchronous belt generates reverse tension during printing, the torque cannot be transmitted to the worm gear through the worm wheel, thus ensuring the mechanical locking of the physical position of the sliding seat. If the transmission mechanism adopts a screw drive pair, the helix angle between the screw and the nut is used to convert the rotational motion into linear displacement, and the position is maintained by the friction between the threads or an additional electromagnetic brake.

[0118] After physical position compensation is completed, the control system can immediately trigger a retest within the remaining time of the current calibration window to re-execute short-term excitation, sampling, and main frequency extraction to verify the compensation effect. If there is still a deviation between the retested main frequency and the target frequency, but it has been reduced to within the allowable range, the compensation result is recorded and the process ends; if the deviation is still large, a second compensation is performed. For equipment that operates for a long time, the control system can also combine the main frequency, compensation displacement, cavity temperature, printing time, and material type measured each time into an equipment feature vector, store it in a local database, or upload it to a cloud diagnostic platform for analyzing synchronous belt fatigue trends, predicting maintenance cycles, and generating replacement warnings.

[0119] Based on the above analysis, it can be seen that this step is not simply mechanical tensioning, but rather establishing closed-loop control through the deviation between the main energy frequency and the target frequency. This converts the tension offset into an executable position compensation amount and simultaneously corrects the resonance suppression parameters in the motion control algorithm, so that the mechanical transmission chain and the control model can return to a matching state together. This enables timely correction of the tension drift of the synchronous belt during long-term, high-temperature, and high-speed printing.

[0120] In one example, after the electric tensioning assembly completes physical position compensation, the control system automatically executes the following parameter refresh logic: if the physical frequency of the electric tensioning assembly is adjusted from 50Hz to 55Hz, the control system synchronously changes the input parameter shaping characteristic frequency used for resonance suppression in the motion control algorithm from 50.0 to 55.0. Since if the software parameters are not synchronously modified after tightening the synchronous belt, the compensation waveform generated by the input shaping algorithm will not match the new physical frequency, resulting in a larger "ghosting." This embodiment ensures that "physical frequency adjustment" and "logic vibration reduction" are completed synchronously through this coupling. If only the physical tension is adjusted without updating the algorithm parameters, the controller's pulse shaping frequency will deviate from the actual mechanical resonance point, leading to the contradiction of "generating new ghosting after compensation."

[0121] While driving the tension motor to complete S-displacement compensation, the control system rewrites the X-axis resonance suppression frequency (or X-axis input shaping frequency) and Y-axis resonance suppression frequency (or Y-axis input shaping frequency) settings stored in the motion control algorithm register in real time according to the corrected actual frequency. Through this operation, the synchronous belt tension is restored to the calibrated range, mechanical hysteresis is reduced, and the center frequency of the algorithm's "notch filter" is perfectly aligned with the adjusted physical resonance point of the synchronous belt. In long-term (e.g., over 50 hours) continuous printing tasks, because the system can continuously and automatically "align" the hardware and software parameters, the difference in surface roughness Ra between the top and bottom layers of the printed parts was reduced by more than 85% in the tests.

[0122] In one implementation scenario, to achieve the transition from "on-the-go calibration" of a single device to "full lifecycle management" of a group of devices, the following data interaction logic between the control system and the cloud-based diagnostic platform is used, which may specifically include:

[0123] Data Upload Phase: A feature vector containing information such as device identification, compensation pulse count, and cavity temperature is constructed. The control system does not simply upload a single compensation value, but rather constructs a feature vector encompassing environmental factors, mechanical physical quantities, and time series. Whenever the system triggers tension compensation or a full-scale review, the control system encapsulates the following data packets and uploads them to the cloud diagnostic platform: device metadata, including the device's unique identifier (SN code), synchronization belt batch number, etc.; compensation dynamic quantities, including the number of step pulses N for this compensation, compensation direction (tensioning / relaxation), etc.; physical state quantities, including a comparison of resonant frequencies before and after compensation (…). r ), current printer cavity temperature Tc, etc.; cumulative power measurement, including cumulative printing time, average printing speed, cumulative number of times the drive motor rotates, etc.

[0124] The cloud-based processing logic includes: a fatigue model based on large datasets of the same model; after receiving multi-dimensional feature vector data, the cloud diagnostic platform inputs it into a pre-set belt fatigue analysis model. This model is trained based on the operating trajectories of thousands of machines of the same model. For example, the training process includes: 1) Linear creep analysis: calculating the cumulative displacement of the sliding seat per unit time. If the displacement increases linearly with time, it is considered normal wear. 2) Nonlinear mutation warning: if the number of compensation steps increases exponentially within a short period (e.g., between two consecutive printing tasks), the cloud model will determine that the synchronous belt has experienced local fiber breakage or tooth shear damage. 3) Lateral group comparison: comparing the compensation slope of the current equipment with the "baseline attenuation curve" of the same batch and under the same ambient temperature.

[0125] Feedback and Interaction Phase: The cloud-based diagnostic platform returns a belt residual life evaluation report based on the calculation results. When the evaluation score is lower than the preset safety threshold, the interaction logic includes:

[0126] 1) Terminal display: The printer's local display terminal pops up a graphic message "Synchronization belt replacement suggestion" to guide the user to check the wear condition of specific locations.

[0127] 2) Parameter fine-tuning: The cloud can send down the corrected "target frequency reference" to adapt to the changes in material damping caused by the aging of the synchronous belt.

[0128] 3) Preventive shutdown: In extreme cases (such as cumulative displacement exceeding 120% of the elastic limit), the cloud will issue a locking command. It is recommended to limit the printing acceleration before replacing the belt to prevent the printhead from being damaged by the mechanical limit due to belt breakage.

[0129] Furthermore, during the cooling phase after the printing job, the control system automatically moves the tool head to a preset calibration position (such as the center point of the frame) and performs a full tension scan. At this time, since there is no real-time constraint from the printing job, a larger amplitude excitation can be performed to obtain a frequency response with an extremely high signal-to-noise ratio, and the in-transit calibration effect during the printing process can be closed-loop verified and residual error corrected based on the scan results.

[0130] Based on the above analysis, this application provides a synchronous belt tension calibration method in transit, including: identifying non-printing idle movement commands from the control command stream to be executed; if the travel time corresponding to the non-printing idle movement command exceeds a preset travel time threshold, then determining the travel time as a calibration window; within the calibration window, controlling the first drive motor and the second drive motor to collaboratively output anti-phase excitation signals so that the displacement amplitude generated by the tool head is less than a preset displacement threshold, and exciting the synchronous belt to vibrate; acquiring the vibration signal of the accelerometer integrated on the tool head, and extracting the energy main frequency of the vibration signal through spectrum analysis; and driving the electric tensioning component to perform physical position compensation according to the deviation between the energy main frequency and the preset target frequency, and synchronously updating the resonance suppression parameters in the control system. In this embodiment, by embedding the calibration timing into the non-printing idle transition phase of the control command flow, controlled excitation is established using the inherent mechanical coupling relationship between the first drive motor, the second drive motor, and the synchronous belt. This ensures that the displacement amplitude generated by the tool head during excitation is less than a preset displacement threshold, thus avoiding interference with the normal printing trajectory. Furthermore, tension state quantification is achieved through spectral analysis of the tool head vibration response. By linking the electric tensioning component with algorithm parameters for compensation, synchronous belt tension drift can be continuously identified and corrected without stopping the printing task. This reduces the probability of path errors, layer deterioration, increased local vibration patterns, and ghosting, improving the dimensional accuracy, surface quality, and operational stability of the CoreXY structure 3D printer during long-cycle continuous operations. It should be understood that the above example is merely illustrative and not limiting. In one possible embodiment, the form of the excitation signal, the spectral analysis method, the tensioning mechanism structure, and the control parameter update method can all be replaced accordingly without departing from the core idea of ​​this application.

[0131] Based on the aforementioned embodiments, further, controlling the first drive motor and the second drive motor to output anti-phase excitation signals in coordination includes: controlling the first drive motor and the second drive motor to generate jitter signals with a phase difference of 180°, and controlling the excitation amplitude of the anti-phase excitation signals through pulse width modulation, so that the displacement amplitude generated by the tool head in the XY plane is less than a preset displacement threshold, the preset displacement threshold being determined according to the positioning accuracy of the printer or the surface quality requirements of the current printing task.

[0132] The first and second drive motors are a pair of synchronous drive units in the CoreXY mechanism. They are connected to corresponding synchronous belt segments. The control system synchronously sends reverse current pulses or micro-amplitude position jitter commands to the two drive motors, maintaining a 180° reverse relationship in the drive phase outputs, thus creating symmetrical excitation on the synchronous belt. The jitter signal is generated by a micro-pulse shaping circuit within the driver and combined with current loop control to achieve stable output, ensuring that the excitation frequency matches the inherent response range of the synchronous belt. Pulse width modulation (PWM) is used to adjust the duration of the effective energizing pulse within each excitation cycle. The control system calculates the duty cycle based on a preset amplitude upper limit, thereby limiting the excitation energy injected into the synchronous belt system, ensuring that the tool head only produces minute oscillations suitable for frequency response identification. Specifically, pulse width modulation controls the instantaneous output torque of the drive motor by changing the average voltage applied to the drive motor windings. When the torque is controlled to be sufficient to excite elastic deformation of the belt body but insufficient to overcome the static friction of the tool head or significantly change its motion inertia, a balance can be achieved between micro-excitation and the relative stability of the tool head position (i.e., the displacement amplitude is less than the preset displacement threshold).

[0133] The preset displacement threshold is dynamically determined by the control system based on the printer's positioning accuracy or the surface quality requirements of the current printing task. Specifically:

[0134] 1) If the current printing task is marked as "high precision" or "high quality surface" mode (e.g., layer thickness less than 0.1mm or printing fine artwork), the control system automatically lowers the preset displacement threshold (e.g., set to 0.02mm-0.03mm) to completely eliminate visual textures that may be caused by vibration.

[0135] 2) If the current printing task is in "rapid prototyping" mode or the mechanical positioning accuracy of the printer itself is low, the control system can appropriately increase the preset displacement threshold (for example, set to 0.05mm-0.08mm) to obtain a higher vibration signal-to-noise ratio and ensure the accuracy of tension recognition.

[0136] For example, in a preferred embodiment, the preset displacement threshold is set to 0.05 mm.

[0137] The displacement amplitude of the tool head in the XY plane is obtained through displacement feedback mounted on the motion platform or calculated from acceleration signals, and is constrained within a preset displacement threshold to avoid perceptible interference to the idle trajectory and current printing quality caused by the excitation process. Furthermore, the excitation frequency of the jitter signal is preferably set to avoid the self-excitation frequency of mechanical friction between the tool head slider and the guide rail to prevent crawling. In practical applications, the first and second drive motors can be stepper motors or servo motors with high-resolution microstepping control capabilities, which have good phase consistency and response stability under small jitter conditions. Other models can also be selected for this component in practical applications; this application embodiment does not limit this selection.

[0138] This method establishes a controlled vibration source on the synchronous belt through dual-motor anti-phase drive, utilizing a 180° phase difference to form a balanced excitation torque, avoiding trajectory deviation introduced by single-sided drive. Simultaneously, PWM (Pulse Width Modulation) is used to limit and suppress excessive displacement, allowing the tension characteristics of the synchronous belt to be excited and acquired without significantly affecting the current position of the tool head. Since the displacement amplitude is limited to a preset displacement threshold (e.g., 0.05mm), the tool head can still maintain near-in-situ operation, and vibration identification and subsequent tension compensation within the calibration window will not disrupt the continuity of the printing task. By adopting this specific implementation method, lateral disturbances of the tool head can be reduced while ensuring a clear excitation response, minimizing layer texture, offset, and local surface fluctuations caused by calibration actions, and improving the stability and forming accuracy of the 3D printer during continuous printing.

[0139] In one possible implementation, the frequency range of the excitation pulse generated by the anti-phase excitation signal covers at least one first-order resonant frequency of the synchronous belt under the target tension state (or standard tension state). Preferably, the coverage range covers the first to third order resonant frequency range of the synchronous belt under the target tension state.

[0140] In this embodiment, "target tension state" refers to the expected tension level or designed preload state of the synchronous belt under current operating conditions. "Target tension state" typically corresponds to the physical parameters of the printer at its optimal forming quality. It can also be described as "standard tension state," which is the reference preload state formed after factory calibration or installation calibration of the synchronous belt. The tension value, effective span, pulley engagement state, and reference stiffness after heating of the synchronous belt under this state are all recorded as the basis for subsequent frequency setting. "At least one first-order resonant frequency" refers to the fundamental mode frequency (fundamental frequency) of the synchronous belt under this state. It is the frequency point where tension changes are most significant and energy distribution is most concentrated. Since the first-order resonant frequency has the highest sensitivity to tension fluctuations and the strongest signal amplitude, including it within the excitation range is the basis for achieving reliable in-transit calibration. "The first to third-order resonant frequency range" refers to the response frequency bands of the fundamental, second, and third-order modes of the synchronous belt under this reference state. Its upper and lower frequency limits can be calculated from the elastic modulus, cross-sectional area, length, and tension of the synchronous belt material, and corrected by combining measured spectra.

[0141] In its implementation, the control system pre-establishes a frequency database based on the synchronous belt model. The pulse frequency of the anti-phase excitation signal is set to a continuous frequency band covering the resonant frequency range, or scanned and output within this band with a preset step, ensuring that the excitation energy can sequentially act on the first-order, and optionally the second and third-order modes. To ensure the capture of frequency shifts caused by tension relaxation, the excitation pulse frequency coverage should have a certain bandwidth. This bandwidth is centered on the first-order resonant frequency under the target tension state, extending with preset frequency margins in both low and high frequency directions. This ensures that even with significant tension drift, the excitation signal can still elicit a measurable resonant response. The anti-phase excitation signal is output collaboratively by the first and second drive motors, maintaining a 180° phase difference. The excitation amplitude is adjusted via pulse width modulation to keep the tool head's displacement in the XY plane within allowable limits (such as the aforementioned preset displacement threshold), thereby exciting the synchronous belt vibration without affecting the idle trajectory. The control system used can be a motion control motherboard with high-frequency PWM output capability. Its internal frequency table is used to quickly call the target frequency band. In practical applications, other models of this component can also be selected. This application embodiment does not limit this.

[0142] This frequency coverage method allows the synchronization band to be fully excited within the calibration window, making it easier to obtain a clear dominant frequency peak in the spectrum sampling results. This facilitates subsequent extraction of the dominant energy frequency and determination of the tension shift direction. Since the coverage range includes at least one first-order resonant intervals, and preferably covers multiple resonant intervals, even if the synchronization band experiences frequency shifts due to temperature increases, fatigue relaxation, or material aging, it can still obtain an effective response within the target frequency band, thereby improving the sensitivity and stability of tension identification.

[0143] By adopting this implementation method, the excitation signal can take into account both the fundamental and higher-order modal responses of the synchronous band, reducing missed detections caused by insufficient excitation at a single frequency point, and improving the completeness of the spectrum analysis. As a result, the system can more accurately determine tension changes, the compensation action of the electric tensioning component can be more targeted, and the resonance suppression parameters in the motion control algorithm can be kept consistent with the actual mechanical state, thereby reducing the probability of printing cracks, layer misalignment, and path deviation.

[0144] Based on the aforementioned embodiments, the electric tensioning assembly driving the printer further performs physical position compensation, including: converting the deviation between the main energy frequency and the target frequency into the target displacement of the slide seat according to the physical characteristic parameters of the synchronous belt; obtaining the number of execution pulses of the tensioning motor in the electric tensioning assembly according to the target displacement; and driving the tensioning motor to drive the slide seat to generate displacement through the transmission mechanism according to the number of execution pulses, so as to change the center distance between the first drive motor, the second drive motor and their opposite driven wheel.

[0145] The physical properties of the synchronous belt include mass density, effective span, cross-sectional area, and elastic modulus. Mass density characterizes the mass distribution per unit length of the synchronous belt; effective span characterizes the actual length of the synchronous belt involved in vibration and force transmission between the two pulleys; cross-sectional area characterizes the geometric parameters of the bearing section of the synchronous belt; and elastic modulus characterizes the stiffness of the synchronous belt material under tension. The dominant energy frequency is the characteristic frequency of concentrated main energy obtained after spectral analysis of the synchronous belt vibration signal, and the target frequency is the reference frequency corresponding to the synchronous belt under the target tension state. The deviation between the two is used to characterize the degree of deviation of the current tension state relative to the reference state.

[0146] In practical implementation, the control system can establish a physical correspondence model between tension and frequency based on the aforementioned physical characteristic parameters. Specifically, the control system first calculates the current tension deviation value of the synchronous belt based on the mass density, effective span, and the square difference between the dominant energy frequency and the target frequency. Subsequently, based on the cross-sectional area, elastic modulus, and effective span of the synchronous belt, Hooke's Law is used to convert the tension deviation value into the required physical elongation or shortening of the synchronous belt. This value corresponds to the target displacement that the sliding seat needs to move. The sliding seat can be mounted on the guide mechanism of the tensioning assembly and linked with the transmission components of the tensioning motor.

[0147] To achieve accurate displacement-to-pulse conversion, the control system can obtain the number of execution pulses from the tensioning motor in the electric tensioning assembly based on the target displacement. Specifically, the control system can query a preset piecewise linear interpolation mapping table. This table pre-stores multiple displacement calibration points and their corresponding pulse conversion relationships, adapting to the nonlinear errors of screw drives, gear drives, or synchronous belt drives within different displacement ranges. This allows the target displacement to be converted into a more accurate number of execution pulses, thereby reducing the impact of mechanical transmission backlash, subdivision errors, and changes in transmission slope across different ranges on compensation accuracy. Furthermore, the calculation of the number of execution pulses also needs to consider the step angle of the tensioning motor and the reduction ratio of the transmission mechanism to ensure that the minimum compensation step size can cover the tension adjustment resolution required by the printer.

[0148] At the mechanical execution level, based on the number of execution pulses, the tensioning motor drives the sliding seat to generate displacement through the transmission mechanism. The tensioning motor can be a stepper motor or a servo motor, which receives the number of execution pulses through a driver and outputs the corresponding angular displacement. The transmission mechanism can consist of a lead screw pair, a screw pair, a worm gear, or a rack and pinion transmission pair, used to convert the rotational motion of the motor into the linear displacement of the sliding seat. When the sliding seat moves along the preset guide rail, it drives the first / second drive motor (or the driven wheel mounted on the sliding seat) mounted on the sliding seat to move as a whole. In practical applications, the sliding seat can be made of aluminum alloy to balance rigidity and weight, and the guide rail can be a linear guide structure to improve movement accuracy.

[0149] With the above structure, when the sliding seat is displaced, it directly changes the center distance between the shafts of the first and second drive motors and their opposite driven pulleys. The center distance refers to the straight-line distance between the center of the output shaft of the drive motor and the center of the shaft of the corresponding driven pulley. An increase or decrease in this distance directly leads to a change in the total length of the synchronous belt closed-loop path, thereby achieving physical compensation for belt tension. This physical position compensation method forms a closed-loop compensation link from frequency identification to mechanical displacement correction, which can convert control commands into stable mechanical adjustment quantities, avoiding deviations caused by manual adjustment and ensuring that the tension compensation process remains consistent with the output of the control system.

[0150] By adopting this implementation method, the tensioning component can perform quantitative compensation based on the actual vibration state of the synchronous belt, improve the tension recovery accuracy, reduce reliance on manual adjustment, and reduce trajectory errors, layer texture aggravation, and resonance amplification caused by tension drift, thereby improving the stability and forming consistency of the printer under long-term continuous printing conditions.

[0151] Based on the aforementioned embodiments, there is a preset proportional mapping relationship between the number of execution pulses and the change in the shaft center distance. The proportional mapping relationship is pre-calibrated according to the transmission ratio of the transmission mechanism and the motion trajectory of the sliding seat.

[0152] Specifically, the number of execution pulses is the direct control command sent by the control system to the tensioning motor, while the change in the shaft center distance is the physical adjustment result that ultimately affects the tension of the synchronous belt. The proportional mapping relationship between the two is a correspondence determined by the inherent mechanical characteristics and spatial geometry of the mechanical transmission chain, and is usually physically manifested as a preset proportional coefficient or linear mapping table.

[0153] The transmission ratio of the transmission mechanism comprehensively reflects the efficiency of transmitting electrical signals from the motor to the mechanical displacement at the output end. This transmission ratio is determined by the inherent step angle of the tension motor, the microstepping ratio of the motor driver, and the mechanical reduction ratio of the transmission components. Taking a lead screw transmission mechanism as an example, the total number of pulses required for the tension motor to rotate one full revolution is calculated by dividing the motor's circumference angle by the step angle and then multiplying it by the driver's microstepping ratio. The linear displacement generated by the transmission mechanism driving the sliding seat during this full revolution of the motor precisely corresponds to the nominal lead of the lead screw. Based on this, the control system can establish the reference mechanical linear displacement that a single input pulse can induce. If the transmission mechanism also includes gear sets or worm gears, the reference linear displacement needs to be further calculated in conjunction with the gear ratio or the reduction ratio of the worm gear pair.

[0154] The trajectory of the sliding block determines the spatial geometric transformation relationship between the actual moving distance of the sliding block and the final change in the center distance acting on the synchronous belt. In the actual mechanical structure, if the extension direction of the sliding block's guide rail is completely parallel to the direction of the axis connecting the drive motor to the opposite driven wheel, then the moving distance of the sliding block is equal to the change in the center distance. If, due to the limited internal space of the frame, the extension direction of the sliding block's guide rail has a specific angle with the aforementioned axis connection direction, then only a portion of the actual moving distance of the sliding block contributes to the change in the center distance. In this case, the control system will convert the actual displacement of the sliding block into an effective change in the direction of the center distance based on the spatial projection relationship (such as the cosine relationship) of this angle. Since this angle is fixed after the mechanical assembly is completed, a stable proportional relationship is maintained between the sliding block's displacement and the change in the center distance.

[0155] In its implementation, the control system establishes and stores the aforementioned proportional mapping relationship through a pre-calibration process. This calibration process is typically completed during the equipment assembly stage at the factory, using high-precision displacement measuring equipment to measure the actual physical change in the shaft center distance under different numbers of command pulses. During the calibration process, the system simultaneously records and compensates for the objectively existing mechanical backlash and transmission idleness in the transmission mechanism. Specifically, the proportional mapping relationship also includes compensation steps for backlash; that is, when the tension motor changes its rotation direction, the control system adds or subtracts a preset number of compensation pulses based on the proportional calculation to offset the influence of the transmission pair gear backlash on the change in shaft center distance, thereby generating an accurate correspondence table or conversion coefficient.

[0156] By pre-calibrating this proportional mapping relationship, the control system can accurately output the corresponding number of execution pulses based on the mapping relationship after determining the required shaft center distance adjustment. This mapping mechanism, which is purely based on the hardware transmission ratio and spatial motion trajectory, effectively shields the interference of machining tolerances and assembly errors on tensioning accuracy, ensuring a high degree of consistency between control commands and the final mechanical response.

[0157] Based on the aforementioned embodiments, the transmission mechanism further includes a worm gear transmission chain or a screw transmission pair.

[0158] If the transmission mechanism is a worm gear drive chain, the torque of the tensioning motor is transmitted through the worm gear drive chain. After the physical position compensation is completed, the self-locking characteristic of the worm gear drive chain when the lead angle is less than the friction angle is used to achieve mechanical locking of the physical position of the sliding seat.

[0159] The worm gear drive chain can consist of a worm shaft, a worm wheel, a bearing housing, and a mounting bracket. The worm shaft is connected to the output shaft of the tensioning motor via a coupling. The worm wheel is coupled to the sliding seat via a threaded pair or a transmission rod to stably transmit the motor torque to the sliding seat after reduction. Specifically, a lead screw can be fixedly connected to the center of the worm wheel, which engages with a nut on the sliding seat to convert the rotation of the worm wheel into the linear displacement of the sliding seat. The worm gear pair can use a copper alloy worm wheel and an alloy steel worm to utilize the stable friction coefficient and high wear resistance of dissimilar metals, thereby improving the meshing load-bearing capacity and wear resistance of the mechanism. In practical applications, other models of this component can also be selected, and this application embodiment does not limit this.

[0160] The core advantage of this mechanism lies in its physical self-locking function. When the lead angle of the worm is designed to be smaller than the equivalent friction angle between the worm wheel and the worm's contact surface, the mechanism possesses self-locking characteristics. In this state, power can only be transmitted from the worm to the worm wheel, and external reverse loads acting on the sliding block (such as the tension of the timing belt) cannot drive the worm to rotate in the reverse direction. This means that when the tension of the timing belt acts on the worm wheel through the sliding block and the lead screw, the worm wheel cannot drive the worm to rotate due to friction. Therefore, after physical position compensation is completed, even if the tensioning motor stops supplying power and loses its electromagnetic holding torque, the physical position of the sliding block can be mechanically locked at the current coordinates, effectively preventing tension retraction caused by high-frequency reversing impacts or power outages in the timing belt.

[0161] If the transmission mechanism is a screw drive pair, the rotational motion of the tensioning motor is converted into linear displacement of the sliding seat. The screw can engage with the nut seat on the sliding seat via a threaded connection. After the tensioning motor drives the screw to rotate, the threaded pair converts the rotational motion into linear displacement along the guide rail direction, thereby moving the sliding seat and changing the shaft center distance. The screw drive pair has high transmission efficiency and positioning resolution, enabling minute and precise adjustments to the shaft center distance. In embodiments using a screw drive pair, anti-reverse washers or lock nuts can also be used to enhance vibration resistance under high-frequency vibration environments.

[0162] The aforementioned transmission structure ensures that the compensation displacement output by the tension motor can be reliably maintained at the preset position. Maintaining the shaft center distance through mechanical means, rather than solely relying on the motor's electromagnetic torque, not only guarantees the long-term stability of the synchronous belt tension but also avoids the risk of overheating from the tension motor maintaining high loads for extended periods. Based on this, the CoreXY mechanism can maintain the rigidity and precision of the transmission chain during long-cycle continuous printing jobs, reducing print defects caused by tension fluctuations.

[0163] In one possible implementation, this application provides a tension control mechanism with self-protection functionality. Specifically, the method includes: by monitoring the current sampling circuit of the tensioning motor, triggering a current-limiting protection action when the sliding block moves to a preset physical stroke threshold, causing a sudden change in load.

[0164] The current sampling circuit of the tension motor can be composed of a series sampling resistor, an operational amplifier, and an analog-to-digital converter. It is used to acquire the instantaneous value, average value, and slope of change of the motor drive current in real time, and send the sampling results to the main processor or a dedicated motor drive chip. The preset physical travel threshold refers to the permissible mechanical boundary position when the sliding seat moves along the linear guide mechanism. This position can be defined by physical limit blocks, limit switches, or displacement thresholds pre-stored in the control system. When the sliding seat moves to this threshold position and comes into contact with the mechanical boundary, the drastic increase in mechanical resistance causes a sudden change in the motor load.

[0165] In terms of physical mechanism, since the output torque of the tensioning motor has a positive correlation with the phase current, when the sliding seat approaches the preset physical stroke threshold and is affected by mechanical constraints such as structural jamming, guide rail end face contact, or disappearance of transmission gap, the output torque of the motor will rise rapidly in order to maintain stepping or speed, thereby causing a momentary surge in the sampling current in the circuit.

[0166] In practical implementation, the control system continuously compares and analyzes the sampled current. The judgment logic includes: when the rise rate (i.e., the current slope) of the current value within a preset time window exceeds a preset change threshold, or when the absolute value of the current is continuously higher than a set multiple of the rated operating current, the system determines that the sliding seat has approached or reached a preset physical travel threshold, and uses this abnormal load state as the trigger condition for current limiting protection.

[0167] The current limiting protection action can be directly executed by the motor driver chip, and specific methods include, but are not limited to: reducing the pulse width modulation (PWM) duty cycle to reduce output power, directly limiting the upper limit of phase current, or immediately cutting off the drive output to put the tensioning motor into a free stop state. This protection mechanism can effectively prevent damage to the lead screw, worm gear, or synchronous belt tensioning mechanism caused by the huge impact force generated by hard collisions.

[0168] Furthermore, in practical applications, this current sampling circuit can also be linked with position feedback signals (such as motor encoder signals). When the displacement monitoring shows that the sliding block is close to the preset physical travel threshold but has not fully reached it, the control system can decelerate in advance and enter the controlled current limiting mode to reduce mechanical shock and improve operational stability. This current monitoring mechanism is not only used for travel limiting, but can also be used to identify faults such as severe entanglement or foreign object jamming of the synchronous belt. This application embodiment does not limit this.

[0169] This implementation method, through real-time monitoring of the tensioning motor's operating current, transforms load anomalies caused by mechanical limit positions or accidental jamming into identifiable electrical signal characteristics. This allows for timely triggering of current-limiting protection when the sliding seat reaches a preset physical travel threshold. This detection method provides a faster response speed than traditional mechanical switches, effectively preventing overcurrent heating of the tensioning motor in a stalled state and mechanical damage to transmission mechanisms (such as worm gears or screws). This mechanism significantly improves the safety and reliability of the tensioning assembly during physical compensation, reduces equipment downtime caused by limit collisions, and lowers long-term maintenance costs.

[0170] Based on the aforementioned embodiments, the resonance suppression parameters in the synchronous update control system are further updated, including: after the physical position compensation is completed, the resonance suppression parameters used to control the X-axis and Y-axis motion in the control system are updated in real time, so that the notch filter center frequency of the algorithm is aligned with the adjusted synchronous band physical resonance frequency.

[0171] The resonance suppression parameter characterizes the frequency at which the control system suppresses the inherent vibrations of the synchronous belt and its transmission structure. In hardware implementation, the resonance suppression parameter can be stored in a resonance suppression frequency register within the control system. This register can be implemented using firmware parameter areas, non-volatile storage areas (such as EEPROM or Flash), or real-time operating parameter areas (RAM-mapped areas). The registers corresponding to the X-axis and Y-axis are used to store frequency settings related to the two motion channels in the CoreXY structure, respectively. Since the motion of the first and second drive motors in the CoreXY structure is coupled to the X and Y axes through the synchronous belt, changes in the synchronous belt tension simultaneously affect the vibration characteristics of both axes. That is, both X-axis and Y-axis motion will excite resonance in the synchronous belt; therefore, it is necessary to synchronously constrain the vibration response in both directions.

[0172] The notch filter center frequency is a core parameter used in motion control algorithms (such as notch filters or input shaping algorithms) to attenuate the target resonant frequency band. When the synchronous belt tension is compensated for physically, the resonant characteristics (i.e., the physical resonant frequency) of the mechanical system shift. At this point, the control system synchronously corrects this parameter based on the compensated actual physical resonant frequency. Under ideal compensation conditions, the adjusted synchronous belt physical resonant frequency should be consistent with the aforementioned preset target frequency; under incomplete compensation conditions, it corresponds to the true natural frequency of the synchronous belt after the compensation action is completed.

[0173] In practical implementation, after confirming that the tensioning component has completed its physical position compensation, the control system reads the compensated synchronous band resonance frequency and converts it into a frequency coefficient or parameter value recognizable by the algorithm. Subsequently, the control system writes the new frequency value to the resonance suppression frequency registers corresponding to the X and Y axes in real time via bus communication, register mapping, or firmware interface refresh. "Real-time update" refers to refreshing the register values ​​after the physical compensation action is completed and before executing the next control command involving the tool head acceleration movement. Since this writing process occurs after physical compensation and does not rely on reassembly or machine downtime for manual intervention, the motion control algorithm can immediately adopt the new notch filter center frequency in the next interpolation cycle to accurately match and suppress the changed mechanical resonance point. For different types of controller chips, the register can be an independent frequency configuration register or a frequency field in the parameter table. In practical applications, other models of this component can also be selected, and this application embodiment does not limit this.

[0174] Its working principle is as follows: when the synchronous belt tension compensation causes a shift in the mechanical resonance frequency, if the control algorithm still uses the old suppression frequency, insufficient vibration suppression (failure to cover the true resonance point) or false suppression (attenuation of the normal motion frequency) will occur, and it may even induce new "ghosting" patterns. By rewriting the resonance suppression frequency registers of the X-axis and Y-axis in real time, the center frequency of the algorithm's notch filter is made consistent with the current physical resonance frequency, so that the vibration suppression characteristics output by the control system are synchronized with the actual mechanical state, thereby continuously suppressing vibration amplification in subsequent motion. This alignment mechanism ensures that the "physical frequency modulation" at the mechanical level and the "logical vibration suppression" at the algorithm level form a closed loop, fundamentally solving the system detuning problem under high-frequency reciprocating motion.

[0175] With this implementation, motion control parameters can be updated in conjunction with the physical compensation results of mechanical tension. By aligning the notch filter center frequency of the algorithm with the adjusted physical resonance frequency of the synchronous band in real time, the vibration damping failure caused by the lag in control frequency after changes in mechanical state is effectively solved. Since the vibrations of the first and second drive motors in the CoreXY structure are coupled to the X and Y axes through the interlacing of the synchronous band, synchronously updating the dual-axis parameters ensures that the dynamic characteristics of the entire machine motion system remain consistent, eliminating asymmetric "ghosting" patterns induced by single-axis frequency offset. This synchronous update mechanism can significantly reduce the probability of residual vibration (vibration marks), path jitter, and layer texture deterioration during the commutation process, and improve trajectory consistency, surface quality, and forming stability under long-term high-speed printing. Because the resonance suppression frequency is dynamically aligned with the physical resonance frequency, the equipment can immediately return to the optimal vibration damping state after physical compensation without additional shutdown for frequency sweeping or manual parameter adjustment, thereby improving the printer's continuous operation capability and forming stability under complex working conditions.

[0176] Building upon the foregoing embodiments, this application further provides a frequency compensation mechanism that considers environmental factors. The method further includes: real-time acquisition of the printer cavity temperature, and dynamic correction of a preset target frequency based on the change in cavity temperature by querying a preset temperature drift compensation table or calling a temperature compensation model.

[0177] The printer cavity temperature refers to the ambient temperature within the enclosed forming space of the additive manufacturing equipment. It is typically collected in real-time by temperature sensors located on the cavity sidewalls, top, or airflow circulation channels. These sensors can be thermistors, digital temperature chips, or thermocouples. Physically, the cavity temperature is considered the equivalent temperature of the thermal environment surrounding the synchronous belt and its transmission mechanism. Logically, the control unit first acquires a reference temperature. This reference temperature can be the ambient temperature recorded during the equipment's factory calibration or the initial temperature at the start of the current printing task. The control unit compares the real-time collected temperature with this reference temperature to determine the temperature difference.

[0178] A preset temperature drift compensation table is used to establish the correspondence between the cavity temperature change and the target frequency correction. The contents of this compensation table are pre-calibrated based on the timing belt material, pulley structure, and overall thermal characteristics of the printer, and stored in the non-volatile memory of the control unit for quick retrieval during operation. During the calibration phase, different temperature gradients are simulated under controlled experimental conditions, and the inherent frequency performance of the timing belt at different temperatures is recorded to determine the compensation values, ensuring that the compensation table covers various extreme operating temperatures the printer may encounter. Furthermore, dynamic correction can also be achieved through a preset temperature compensation model. This model uses the temperature change as the independent variable and calculates the target frequency correction value using a preset compensation function.

[0179] In actual operation, the control unit continuously receives the current cavity temperature and compares it with the reference temperature to obtain the change. Then, it queries the temperature drift compensation table or performs model calculations according to the change to obtain the corresponding frequency correction value. The correction value is then superimposed or applied to the original preset target frequency to form a corrected target frequency that dynamically floats with the ambient temperature.

[0180] The dynamically corrected target frequency can be used for subsequent tension determination, spectrum comparison, or resonance suppression parameter updates, enabling real-time offset compensation of the target frequency as the cavity thermal environment changes. For synchronization belts made of different materials (e.g., polyurethane, neoprene, or composite materials with reinforcing cores), the control unit can also call compensation curves related to the temperature response characteristics of specific materials to adapt the entries in the table, thereby improving the consistency of frequency determination under high-temperature cavities, temperature fluctuations, or long-term continuous printing conditions. For example, for polyurethane synchronization belts with high thermal sensitivity, the system will set a larger frequency correction weight to compensate for its elastic modulus, which decreases significantly with increasing temperature. In practical applications, the compensation table can also use other data calibration or logical mapping methods, which are not limited in this embodiment.

[0181] This solution continuously monitors the cavity temperature and dynamically corrects the target frequency based on temperature changes. This proactively offsets temperature-related thermal expansion and contraction effects, preventing target frequency drift caused by temperature increases or decreases and thus reducing tension calibration errors. From a physical perspective, the Young's modulus of the synchronization belt and the geometry of its mechanical structure change with temperature, leading to a shift in the natural frequency under the same tension. This solution introduces temperature compensation to ensure a constant "frequency-tension" mapping under different thermal conditions. Since the synchronization belt is in a closed cavity, its physical state is directly affected by the ambient thermal field. Correcting the target frequency reference effectively prevents the system from misinterpreting frequency drops caused by thermal softening as mechanical relaxation. Because the target frequency remains consistent with the actual thermal environment, the reference for subsequent physical position compensation and resonance suppression parameter updates is more stable, contributing to improved tension calibration accuracy, motion control consistency, and forming quality stability during long-term printing processes.

[0182] Building upon the foregoing embodiments, this application further provides an environmental perception-based compensation and protection mechanism. Specifically, this method includes: determining the current environmental vibration level of the printer by monitoring the noise floor of an accelerometer in a non-excited state; and suspending physical position compensation if the current environmental vibration level exceeds a preset threshold.

[0183] The accelerometer can be a triaxial MEMS accelerometer, mounted inside the tool head housing or on the tool head bracket, used to collect background vibration signals from the printer in a static state. The non-excited state refers to a specific time window, specifically the period when the first and second drive motors do not output anti-phase excitation signals and the synchronous belt is not excited to vibrate. Preferably, the non-excited state is located at the beginning of the calibration window, i.e., before controlling the first and second drive motors to output anti-phase excitation signals, a short period of background noise detection is performed using the accelerometer. The signals collected by the sensor at this time mainly reflect the ground vibration around the equipment, the coupled vibration generated by the operation of adjacent equipment, and the background noise formed by the residual vibration of the printer's own fan or transmission mechanism.

[0184] In terms of data processing logic, the control system can set a short silent sampling period before the calibration window begins to perform statistical analysis on the acquired background noise signal. This analysis includes, but is not limited to, calculating the root mean square amplitude of the signal to evaluate the total energy, or calculating the peak-to-peak value of the signal to identify instantaneous impacts. The control system maps these statistical results to a preset environmental vibration level to identify whether the current external disturbance will mask the true physical characteristics of the synchronization band. The environmental vibration level physically characterizes the intensity of background noise interference with subsequent excitation signals.

[0185] In practical implementation, the environmental vibration level can be defined by a preset threshold table. Different levels correspond to different noise levels when the background noise amplitude falls into different ranges. This threshold table can be stored in the non-volatile memory of the control system and can be updated based on the equipment installation environment, foundation stiffness, and the vibration background of the printer. When the detected environmental vibration level exceeds the preset threshold, it means that the current environmental noise is too high, which may lead to inaccurate resonance frequency identification. At this time, the control unit will immediately freeze the output command of the tension motor, keep the current position of the sliding seat unchanged, and put the current compensation request into a waiting state. Suspending the execution of physical position compensation means skipping the physical adjustment action within the current calibration window to prevent incorrect tension compensation in low signal-to-noise ratio environments.

[0186] Furthermore, the system continuously or periodically monitors the background noise until subsequent detection results fall below a safe threshold before automatically resuming physical position compensation. This mechanism first establishes an environmental baseline using the background noise before deciding whether to enter the compensation execution phase, ensuring that physical position compensation is always under controllable, low-interference conditions. Since the compensation action relies on the actual vibration frequency characteristics of the synchronous belt, pausing execution effectively avoids misinterpreting strong external interference as synchronous belt resonance, thereby preventing the tensioning motor from performing incorrect displacement compensation and maintaining consistency between the control algorithm and the mechanical state. In practical applications, other models with different ranges, sampling rates, or packaging forms of the accelerometer can also be selected; this application does not limit these options.

[0187] By adopting the above method, this solution establishes an environmental vibration benchmark before compensation, enabling the printer to autonomously identify and defend against external interference. By monitoring the noise floor in non-excited conditions, the system can effectively distinguish between "real resonance signals from the synchronous band" and "external environmental interference signals," thus automatically suppressing ineffective compensation actions in scenarios with high environmental vibration. This "sniffing out the noise floor first, then performing compensation" logic ensures that physical compensation actions are always based on a reliable signal-to-noise ratio. This not only significantly reduces the impact of external mechanical disturbances on tension calibration accuracy and improves the reliability and repeatability of compensation results, but also avoids quality risks such as trajectory deviations and abnormal printing textures (e.g., vibration marks, layering faults) caused by erroneous compensation. This solution is particularly suitable for industrial printing environments with multiple devices operating in parallel, complex ground vibration sources, or periodic impacts outside the cavity, ensuring consistent forming quality under complex working conditions.

[0188] Building upon the foregoing embodiments, this application further provides a closed-loop verification mechanism after a printing task. The method further includes: during the cooling phase after the printer finishes printing, controlling the tool head to move to a preset calibration position and performing a full tension scan and verification.

[0189] The printer is preferably a CoreXY structure 3D printer. The preset calibration position can be set in a dedicated idle calibration area outside the printing forming area, or in a standby position near the edge of the frame that does not affect the removal of the heated bed and the formed part. The purpose of setting the preset calibration position is that, since the resonant frequency of the synchronous belt is closely related to the effective span of the belt (i.e., the distance between the pulleys), by fixing the tool head at a specific coordinate point, the effective span of the synchronous belt can be kept constant during each full scan, thereby eliminating the interference of position variables on the tension determination results. The cooling stage refers to the period after the printing task is completed, when the cavity heating element is turned off, the temperature gradually drops, the extrusion system stops forming output, and the motion control enters the final state. Performing tension verification during this period can take advantage of the equipment downtime window to obtain measurement data with a higher signal-to-noise ratio in an environment without printing vibration interference.

[0190] The full-volume tension scan and verification process differs from the in-transit calibration within the aforementioned calibration window. After the tool head moves to the preset calibration position, a scanning excitation covering a wider frequency band is applied to the synchronous belt (rather than narrow-frequency excitation only targeting the target frequency), while simultaneously acquiring the response signals from the first drive motor, the second drive motor, and the tool head. The full-volume tension scan refers to performing a broadband frequency sweep covering the entire frequency range of the synchronous belt under various possible tension states while the tool head is stationary, to obtain the current absolute natural frequency of the synchronous belt. During the scan, the control system can sequentially output excitation parameters of different amplitudes and frequencies according to a preset frequency sequence, causing the synchronous belt to generate forced vibrations at multiple frequency points. The resonant characteristic spectrum is then extracted by combining the results with feedback signals from the acceleration sensor or the motor side.

[0191] The logic of closed-loop verification of the in-transit calibration effect based on the scan results lies in comparing the actual resonant frequency extracted from the full scan with the expected target frequency range after the aforementioned in-transit calibration. Closed-loop verification refers to evaluating the compensation accuracy of the in-transit calibration algorithm in a dynamic environment by comparing the full scan results under static conditions with the in-transit calibration records during the printing process. If the verification results show that the deviation is still within the allowable threshold range, the verification is passed, and the current state is recorded as stable; if the deviation exceeds the limit (e.g., due to excessive tension caused by thermal shrinkage), the control system can continue to drive the electric tensioning component for secondary fine-tuning according to the deviation amount and re-record the calibration results to form a traceable tension closed-loop management from "in-transit monitoring" to "end-of-line verification". In addition, the verification results can also be used to correct the compensation gain coefficient of in-transit calibration in subsequent printing tasks.

[0192] The guide rail travel range and safety boundary corresponding to the preset calibration position can be written into the control parameter table at the factory. In practical applications, this position can also be flexibly adjusted according to the machine size, cavity structure, and maintenance habits. This application embodiment does not limit this. By supplementing more complete frequency domain detection in non-production states, this mechanism can identify minute tension drifts that are not yet apparent in high-speed printing or high-temperature environments, ensuring that the equipment is in optimal physical condition upon the next startup.

[0193] This solution achieves secondary verification and accuracy closure of in-transit calibration results by introducing a full-volume tension scan during the cooling phase after the printing process. Due to the high temperature and high-frequency motion during printing, the synchronous belt may experience instantaneous thermal expansion or dynamic relaxation; a full-volume scan during the cooling phase can capture residual deviations caused by material thermal shrinkage, mechanical springback, or long-term stress relaxation. Standardized measurements at preset calibration positions eliminate effective span deviations caused by the randomness of the tool head position during printing, ensuring the uniqueness of the verification benchmark. This not only reduces the burden of manual inspection before the next print run but also helps maintain the long-term stability of the synchronous belt drive, thereby improving dimensional consistency, surface quality, and continuous production reliability.

[0194] In one possible implementation, this application provides a data-driven synchronous belt life prediction mechanism. Specifically, the method includes: recording the cumulative compensation stroke of the electric tensioning assembly; when the cumulative compensation stroke exceeds a preset compensation stroke threshold, outputting a belt replacement warning; and uploading a feature vector containing equipment identification, compensation pulse count, and cavity temperature to a cloud-based diagnostic platform to receive a belt residual life evaluation report.

[0195] The electric tensioning assembly may include a tensioning motor, a reduction gear transmission mechanism, and a sliding seat connected to the mounting brackets of the first and second drive motors. After each tension compensation operation, the control system reads the number of output pulses from the tensioning motor or obtains the actual displacement of the sliding seat through a displacement sensor, and accumulates the single compensation amounts to form a cumulative compensation stroke that reflects the cumulative effect of plastic deformation of the synchronous belt. The cumulative compensation stroke physically characterizes the total permanent elongation of the synchronous belt due to long-term stretching, fatigue, and creep.

[0196] Regarding the feature vector uploaded to the cloud, as a structured data carrier, it contains core dimensions reflecting the health status of the equipment: the equipment identifier is used to uniquely identify the printer, facilitating the cloud diagnostic platform to retrieve the equipment's model parameters, manufacturing date, and historical calibration records; the number of compensation pulses is related to the total work done by the tensioning motor, characterizing the mechanical fatigue strength of the synchronous belt and the wear degree of the transmission mechanism during the cumulative tensioning process; the number of compensation pulses has a definite proportional conversion relationship with the cumulative compensation stroke, and uploading the pulse count enables the cloud platform to obtain higher resolution mechanical adjustment details; the cavity temperature is used to reflect the thermal environment of the synchronous belt during long-term operation. Since the polymer material of the synchronous belt will accelerate oxidation and creep at high temperatures, the temperature data is used to correct the aging rate caused by mechanical wear through thermal load. The above parameters can be cached locally by the control system and sent to the cloud diagnostic platform through a wired network module (such as Ethernet) or a wireless communication module (such as Wi-Fi / 4G / 5G) when the upload conditions are met (such as printing completion, timed trigger, or threshold trigger). In practical applications, other models of communication modules can also be selected, and this application embodiment does not limit this.

[0197] In the local logic, the control system can pre-write a compensation stroke threshold, which can be set based on the fatigue characteristics of the timing belt material (such as steel wire core or glass fiber core), the typical printing time of the equipment, and the operating temperature range of the cavity. When the accumulated compensation stroke reaches the threshold, the control system generates a timing belt replacement warning and outputs it on the operation interface, remote maintenance terminal, or equipment alarm light to prompt maintenance personnel to arrange a shutdown for maintenance. The preset compensation stroke threshold is usually set as the critical displacement value at which the timing belt undergoes irreversible plastic deformation and is about to enter the fracture failure stage.

[0198] At the cloud-based collaborative level, the cloud-based diagnostic platform, based on a pre-built lifespan evolution model, large-scale sample data from historical equipment of the same model, and the equipment's operating trajectory, performs in-depth analysis of feature vectors and outputs a belt residual lifespan assessment report containing information such as replacement recommendations and estimated remaining working hours. This report can be sent back to the local control system for dynamic adjustment of maintenance plans. For example, if the report shows that the belt's residual lifespan is below a preset percentage, the control system can automatically reduce the acceleration limit of subsequent printing jobs to extend the belt's lifespan. This combination of local early warning and in-depth cloud-based diagnostics ensures the reliable operation of the synchronous belt throughout its entire lifespan.

[0199] This solution continuously records the cumulative compensation stroke, transforming the physical compensation of the tensioning component into a quantifiable lifespan criterion. This prevents sudden breakage or loss of precision caused by the synchronous belt continuing to operate when fatigue is nearing its limit. More importantly, by encapsulating equipment identification, compensation pulse count, and cavity temperature into feature vectors and uploading them to the cloud, a dual-dimensional evaluation of mechanical and thermal stress is achieved. Since the compensation pulse count directly reflects the total mechanical displacement performed to maintain tension, its value is positively correlated with the creep and wear of the synchronous belt. After receiving the feature vectors, the cloud diagnostic platform can combine historical big data to make individualized and accurate predictions of the belt's aging status. This transforms replacement warnings from experience-based judgments to data-driven predictive maintenance, thereby reducing the risks of printing misalignment, forming scrap, and unplanned downtime caused by synchronous belt failure and improving the operational efficiency of the equipment cluster.

[0200] Building upon the foregoing embodiments, this application further provides an improved scheme for underlying driving and signal optimization. Specifically, this method includes: controlling the tension motor to operate in a micro-step driving mode with at least 16 microsteps; and filtering out fixed-frequency interference caused by the cooling fan in the accelerometer signal using a digital filtering module.

[0201] The electric tensioning assembly may include a tensioning motor, a reduction gear mechanism driven by the tensioning motor, and a transmission pair for moving the sliding block along a predefined guide direction. When the tensioning motor uses a stepper drive, micro-step control with a minimum of 16 microsteps (e.g., 16 microsteps, 32 microsteps, 64 microsteps, or higher) refines the angular displacement corresponding to each drive pulse. This high-microstep mode not only improves the physical position resolution during the tension compensation process, allowing the number of execution pulses calculated in the aforementioned steps to correspond to finer mechanical displacement increments, but more importantly, it reduces the instantaneous acceleration jumps of the sliding block during movement, thereby avoiding additional disturbances to the synchronous belt tension state caused by the compensation action itself.

[0202] Regarding signal processing, the digital filtering module can be integrated into the control unit and implemented by a digital signal processor, embedded processor, or filtering algorithm program on the control board. Its core logic involves performing frequency domain analysis on the vibration sampling sequence output by the accelerometer, and applying band-stop or notch filtering to the fixed-frequency interference caused by the cooling fan speed and its harmonics, in order to retain the true vibration components of the synchronous band and suppress irrelevant noise in the environment. Since the cooling fan is usually integrated into the tool head and shares a rigid support with the accelerometer, the mechanical vibration it generates is a strong near-field interference that must be eliminated by the algorithm.

[0203] Specifically, regarding interference from cooling fans, since fans typically operate at a constant or controlled speed, the resulting mechanical vibrations and acoustic noise manifest as significant fixed-frequency interference in the frequency spectrum. These interference frequencies are usually closely related to the fan's rated speed, number of blades, and the resonant frequency of the mounting structure. Digital filtering modules precisely attenuate the energy of these known frequency bands by applying band-stop or notch filtering, thus preserving the true inherent vibration components of the synchronous band. "Fixed frequency band" refers to the characteristic frequency range corresponding to a stable fan speed during a specific printing process stage; if the fan speed is dynamically adjusted according to the printing task, the control system updates the cutoff frequency of the digital filtering module in real time based on the currently issued fan PWM commands.

[0204] In practical applications, the center frequency of a fixed frequency band can be estimated based on the fan's physical parameters (such as the product of rotational speed and the number of blades), and can be dynamically corrected by combining the measured spectrum of the equipment in a silent state. This mechanism ensures that the subsequent energy main frequency extraction algorithm can be locked onto the true synchronous band characteristics, avoiding frequency reference shifts caused by fan noise. The digital filtering module and driving mode can also be implemented in other ways depending on the specific hardware architecture; this application does not limit this implementation.

[0205] In this approach, the combination of high-resolution driving and targeted digital filtering significantly improves the microscopic accuracy of tension adjustment and the reliability of signal processing. The electric tensioning assembly operates in a micro-step mode with at least 16 microsteps, refining the motor's stepping motion into smaller angular displacements. This achieves sub-micron-level step control of the shaft center distance at the physical level, reducing the impact of mechanical backlash and stepping pulsation on tension adjustment accuracy and avoiding overshoot during adjustment. Simultaneously, the digital filtering module eliminates fixed-frequency interference caused by the cooling fan, removing "false characteristic peaks" in the spectrum analysis and ensuring that the extracted energy frequency truly reflects the physical tension state of the synchronous belt. Since the cooling fan is usually located in the compact space of the tool head along with the accelerometer, its high-frequency vibration can easily mask the low-frequency resonance of the synchronous belt. This solution ensures the signal-to-noise ratio during in-transit calibration through frequency domain "denoising." As a result, the equipment maintains extremely high frequency recognition accuracy and tension control stability even under continuous operation in a high-temperature enclosed cavity and with strong air cooling.

[0206] Figure 2 A schematic diagram of the structure of a printer provided in this application embodiment is shown below. Figure 2 As shown, the printer 20 provided in this embodiment includes:

[0207] The motion actuator 201 is the core motion unit of the printer, preferably employing a CoreXY architecture. It includes a first drive motor, a second drive motor, a synchronous belt wound between the pulleys, and a tool head that moves in the XY plane driven by the synchronous belt. Specifically, an accelerometer is integrated into the tool head to capture the vibration signal of the synchronous belt under excitation conditions in real time; the accelerometer is electrically connected to the control system 203 via a digital communication interface (such as I2C or SPI bus).

[0208] The electric tensioning assembly 202, serving as the actuator for tension adjustment, includes a tensioning motor, a transmission mechanism (such as a worm gear transmission chain, screw transmission pair, or reduction gear set) coupled to the output of the tensioning motor, and a sliding seat driven by the transmission mechanism. The sliding seat is connected to a first drive motor, a second drive motor, or a driven idler wheel. Specifically, the first drive motor, the second drive motor, or the driven wheel is mounted on the sliding seat. The displacement of the sliding seat changes the axial center distance between the first drive motor, the second drive motor, and their opposite driven wheel, thereby achieving physical compensation for the tension of the synchronous belt. This structural design ensures mechanical rigidity and position self-locking capability during the adjustment process.

[0209] The control system 203 is electrically connected to the accelerometer, the first drive motor, the second drive motor, and the tension motor, forming a closed loop of signal feedback and command output. The electrical connection includes sending excitation signals to the first and second drive motors and sending compensation pulses to the tension motor via the motor drive circuit. The control system 203 is configured to execute the method described above.

[0210] In terms of hardware implementation, the aforementioned control system 203 can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices. The general-purpose processor can be a microprocessor or any conventional processor. The control system 203 integrates an instruction recognition module, a spectrum analysis module, and a motion control module. It executes software instructions stored in memory through a hardware processor to achieve vibration control of the first and second drive motors, real-time sampling and processing of acceleration signals, and pulse drive of the tension motor. The steps in the method embodiments disclosed in this application can be directly implemented by the hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0211] In addition, printer 20 may include memory for storing calibration parameters, temperature drift compensation tables, and historical feature vectors, as well as a network interface module for communicating with a cloud platform. This integrated hardware layout enables the printer to autonomously monitor and maintain tension while performing complex printing tasks, ensuring long-term compatibility between the mechanical system and the control algorithm.

[0212] The printer provided in this application achieves closed-loop control of synchronous belt tension during transit by integrating an acceleration sensor into the tool head and constructing a vibration-sampling-execution hardware link under unified control of the control system. This architecture utilizes the tool head as a natural vibration sampling point to directly obtain the most accurate physical response of the synchronous belt. Simultaneously, through the mechanical coupling of the electric tensioning component with the first drive motor, second drive motor, or driven wheel, the device possesses the ability to automatically respond to tension drift without disassembly or manual intervention. This high degree of hardware and software synergy effectively solves the problem of tension inaccuracy in printers under high temperature, long-term operation, and frequent reversing conditions, significantly reducing the risks of path errors, vibration marks, and surface defects, ensuring consistent dimensional accuracy and surface quality in batch production. Furthermore, by integrating the tensioning motor with the transmission mechanism, digital quantitative control of tension adjustment is achieved, replacing traditional manual experience-based adjustment.

[0213] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the methods provided above.

[0214] By pre-storing the program instructions for implementing the synchronous belt tension in-transit calibration method in a computer-readable storage medium, the printer control system's processor can directly call and execute these instructions. When the processor runs the program instructions, the device can dynamically parse the control instruction stream to be executed (such as a G-code stream), identify non-printing idle movement instructions, and determine the calibration window in real time. This allows for the automatic completion of a series of complex actions, including synchronous belt vibration excitation, frequency acquisition, main frequency extraction, tension compensation, and control parameter updates, without interrupting the printing task. This enables the tension sensing, physical calibration, and algorithm linkage to be deployed in software, thereby improving the stability, portability, and consistency of repeated execution of the method. Therefore, it can continuously suppress the impact of tension drift on tool head trajectory accuracy, surface quality, and overall machine operational stability under long-term, high-temperature, and high-dynamic operating conditions.

[0215] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the methods described in any of the above method embodiments. The program product may be embodied as firmware, a driver, or a functional module integrated into print control software. The computer program product is stored in a computer-readable storage medium.

[0216] All or part of the steps in the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a readable memory. When the program is executed, it performs the steps of the above-described method embodiments; and the aforementioned memory (storage medium) includes: read-only memory (ROM), random access memory (RAM), flash memory, registers, hard disk, solid-state drive, magnetic tape, floppy disk, optical disk, and cloud-based virtual memory and any combination thereof. These media ensure that instructions can be stably read and invoked in different hardware architectures (from the underlying microcontroller to the upper-level server). In particular, for consumer-grade 3D printers, the storage medium is preferably a non-volatile memory integrated on the main control board for persistently storing key data such as the preset target frequency, temperature drift compensation table, and cumulative compensation stroke.

[0217] This application describes embodiments with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processing unit of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processing unit of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0218] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0219] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0220] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of this application. Therefore, if these modifications and variations to the embodiments of this application fall within the scope of the claims of this application and their equivalents, this application also intends to include these modifications and variations.

[0221] In this application, the term "comprising" and its variations can refer to non-limiting inclusion; the term "or" and its variations can refer to "and / or". The terms "first", "second", etc., in this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. In this application, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0222] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this application.

[0223] It should be further noted that although the steps in the flowchart are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowchart may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0224] It should be understood that the above-described device embodiments are merely illustrative, and the device of this application can also be implemented in other ways. For example, the division of units / modules in the above embodiments is only a logical functional division, and there may be other division methods in actual implementation. For example, multiple units, modules, or components may be combined, or integrated into another system, or some features may be ignored or not executed.

[0225] Furthermore, unless otherwise specified, the functional units / modules in the various embodiments of this application can be integrated into one unit / module, or each unit / module can exist physically separately, or two or more units / modules can be integrated together. The integrated units / modules described above can be implemented in hardware or as software program modules.

[0226] When integrated units / modules are implemented in hardware, the hardware can be digital circuits, analog circuits, etc. The physical implementation of the hardware structure includes, but is not limited to, transistors, memristors, etc. Unless otherwise specified, the processor can be any suitable hardware processor, such as a CPU, GPU, FPGA, DSP, and ASIC, etc. Unless otherwise specified, the storage unit can be any suitable magnetic or magneto-optical storage medium, such as Resistive Random Access Memory (RRAM), Dynamic Random Access Memory (DRAM), Static Random Access Memory (SRAM), Enhanced Dynamic Random Access Memory (EDRAM), High-Bandwidth Memory (HBM), Hybrid Memory Cube (HMC), etc.

[0227] If the integrated unit / module is implemented as a software program module and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard drive, magnetic disk, or optical disk.

[0228] In the above embodiments, the descriptions of each embodiment have their own emphasis. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments. The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification.

[0229] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0230] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A method for calibrating synchronous belt tension en route, characterized in that, The method includes: Identify non-printing idle movement instructions from the control instruction stream to be executed. If the travel time corresponding to the non-printing idle movement instruction exceeds a preset travel time threshold, then determine the travel time as a calibration window. Within the calibration window, the first drive motor and the second drive motor are controlled to output anti-phase excitation signals in coordination, so that the displacement amplitude generated by the tool head is less than a preset displacement threshold, and the synchronous belt is excited to generate vibration. Vibration signals from an accelerometer integrated on the tool head are collected, and the energy frequency of the vibration signals is extracted through spectrum analysis. Based on the deviation between the main energy frequency and the preset target frequency, the electric tensioning component is driven to perform physical position compensation and the resonance suppression parameters in the control system are updated synchronously.

2. The method according to claim 1, characterized in that, The control of the first drive motor and the second drive motor to output anti-phase excitation signals in coordination includes: The first and second drive motors are controlled to generate jitter signals with a phase difference of 180°, and the excitation amplitude of the anti-phase excitation signal is controlled by pulse width modulation, so that the displacement amplitude of the tool head in the XY plane is less than the preset displacement threshold. The preset displacement threshold is determined according to the positioning accuracy of the printer or the surface quality requirements of the current printing task.

3. The method according to claim 2, characterized in that, The frequency range of the excitation pulse generated by the anti-phase excitation signal includes at least the first-order resonant frequency of the synchronous belt under target tension.

4. The method according to claim 1, characterized in that, The drive-electric tensioning assembly performs physical position compensation, including: Based on the physical characteristic parameters of the synchronous band, the deviation between the energy main frequency and the target frequency is converted into the target displacement of the sliding block; The number of execution pulses of the tensioning motor in the electric tensioning assembly is obtained based on the target displacement; Based on the number of execution pulses, the tensioning motor is driven to move the sliding seat through the transmission mechanism to change the center distance between the first drive motor, the second drive motor and their opposite driven wheel.

5. The method according to claim 4, characterized in that, There is a preset proportional mapping relationship between the number of execution pulses and the change in the center distance of the shaft. The proportional mapping relationship is pre-calibrated based on the transmission ratio of the transmission mechanism and the motion trajectory of the sliding seat.

6. The method according to claim 4, characterized in that, The transmission mechanism includes a worm gear transmission chain or a screw transmission pair; If the transmission mechanism is a worm gear transmission chain, the torque of the tensioning motor is transmitted by the worm gear transmission chain, and after the physical position compensation is completed, the self-locking characteristic of the worm gear transmission chain when the lead angle is less than the friction angle is used to achieve mechanical locking of the physical position of the sliding seat. If the transmission mechanism is a screw drive pair, then the rotational motion of the tensioning motor is converted into the linear displacement of the sliding seat using the screw drive pair.

7. The method according to claim 4, characterized in that, The method further includes: By monitoring the current sampling circuit of the tensioning motor, a current limiting protection action is triggered when the sliding seat moves to a preset physical stroke threshold, causing a sudden change in load.

8. The method according to claim 1, characterized in that, The resonance suppression parameters in the synchronous update control system include: After the physical position compensation is completed, the resonance suppression parameters used to control the X-axis and Y-axis motion in the control system are updated in real time to align the notch filter center frequency of the algorithm with the adjusted physical resonance frequency of the synchronous band.

9. The method according to claim 1, characterized in that, The method further includes: The printer cavity temperature is collected in real time, and the preset target frequency is dynamically corrected based on the change in the cavity temperature.

10. The method according to claim 1, characterized in that, The method further includes: The ambient vibration level of the printer is determined by monitoring the background noise of the accelerometer in a non-excited state. If the ambient vibration level exceeds a preset threshold, the physical position compensation is suspended.

11. The method according to claim 1, characterized in that, The method further includes: During the cooling phase after the printing job is completed, the tool head is automatically controlled to move to the preset calibration position, perform a full tension scan, and perform closed-loop verification of the effect of the in-transit calibration based on the scan results.

12. The method according to claim 1, characterized in that, The method further includes: Record the cumulative compensation stroke of the electric tensioning component. When the cumulative compensation stroke exceeds a preset compensation stroke threshold, output a belt replacement warning. The feature vector containing the device identifier, the number of compensation pulses, and the cavity temperature is uploaded to the cloud diagnostic platform to receive the belt residual life evaluation report.

13. The method according to claim 4, characterized in that, The method further includes: The tensioning motor is controlled to operate in a micro-step drive mode with a minimum of 16 microsteps. The fixed-frequency interference caused by the cooling fan in the accelerometer signal is filtered out by a digital filtering module.

14. A printer, characterized in that, include: The motion actuator includes a first drive motor, a second drive motor, a synchronous belt, and a tool head integrating an acceleration sensor; An electric tensioning assembly includes a tensioning motor, a transmission mechanism coupled to the output end of the tensioning motor, and a sliding seat driven by the transmission mechanism. The sliding seat is connected to a first drive motor, a second drive motor, or a driven wheel. The control system is electrically connected to the acceleration sensor, the first drive motor, the second drive motor and the tension motor respectively, and the control system is configured to perform the method as described in any one of claims 1-13.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1 to 13.

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