A large-span steel structure roof cumulative sliding construction in-place deviation real-time correction method

Abstract

The application relates to a large-span steel structure roof cumulative sliding construction deviation real-time correction method. The method comprises the following steps: based on the assembled frame quality and the centroid coordinate, the center of gravity position change and the theoretical counterforce are calculated; the weighing sensor is diagnosed to obtain a sensor health sign; based on the sensor health sign, the measured counterforce is corrected to obtain a soft measurement counterforce, the soft measurement counterforce and the theoretical counterforce are weighted and summed to obtain a fusion counterforce; based on the fusion counterforce and the measured thrust, a friction coefficient estimation value is calculated, based on the center of gravity position change, the friction coefficient estimation value and the fusion counterforce, a feedforward thrust is calculated; based on the feedforward thrust and the measured displacement, feedback correction is carried out to obtain a feedback correction amount. By adopting the method, the counterforce distribution change caused by the center of gravity change can be introduced in real-time deviation correction, and the reliability of the in-place deviation correction is effectively improved in combination with the soft measurement fusion degradation.

Description

Technical Field

[0001] This invention belongs to the field of industrial data prediction and quantification, and in particular relates to a real-time correction method for cumulative sliding construction positioning deviation of large-span steel structure roofs. Background Technology

[0002] With the development of construction technology for large-span steel structure roofs, cumulative sliding construction technology has become the mainstream construction method for large stadiums, airport terminals, and other projects due to its advantages such as less high-altitude work, high assembly precision, and minimal impact on the substructure. This technology involves assembling the roof sections on the ground and then gradually sliding them into place along a track, placing extremely high demands on the synchronization and uniformity of stress during the sliding process. Current control methods generally employ a displacement synchronization control strategy, which involves placing displacement sensors at each traction point, using the displacement difference as a feedback signal, and relying on PID-type algorithms to adjust the thrust at each point, striving to ensure that each point moves at the same speed.

[0003] In traditional technologies, the thrust distribution at each traction point is often based on a preset uniform ratio or the experience judgment of construction personnel, lacking real-time perception of the dynamic changes in the actual vertical reaction force at the support points. The control system uses displacement deviation as the sole basis for correction. When factors such as track settlement, slide plate wear, and sudden changes in local friction coefficient cause the resistance distribution at each support point to deviate from the preset value, the mismatch between thrust and resistance can only be passively and laggingly corrected through displacement feedback. In addition, during the sliding process, the center of gravity of the roof gradually shifts backward with the cumulative assembly, and the theoretical reaction force at each support point is redistributed accordingly. However, traditional methods do not incorporate this trend into feedforward control, resulting in additional synchronization deviations after each change in the center of gravity.

[0004] However, current displacement synchronization methods have several fundamental problems. First, the true stress state of each slip shoe cannot be directly known, thrust adjustment lacks a mechanical basis, and the cumulative effect of deviations is significant. Second, when the load cells at the fulcrum fail due to harsh environments, mechanical collisions, or circuit faults, there is a lack of effective degradation measures, forcing reliance on purely theoretical reaction forces or manual intervention, severely impacting construction continuity. Third, the quantitative impact of center of gravity changes on reaction force distribution is not fully utilized, and the control strategy lacks foresight, leading to frequent unnecessary correction actions during slippage, increasing the risk of additional internal forces and positioning accuracy. Summary of the Invention

[0005] Therefore, it is necessary to provide a real-time correction method for cumulative slippage positioning deviation of large-span steel structure roofs that can integrate changes in the center of gravity and introduce soft measurement for reaction force calculation to improve the reliability of error correction.

[0006] Firstly, this application provides a method for real-time correction of cumulative sliding construction positioning deviations in large-span steel structure roofs, including:

[0007] Obtain the mass and centroid coordinates of the assembled vehicle, and calculate the change in center of gravity and theoretical reaction force based on the mass and centroid coordinates of the assembled vehicle;

[0008] Measured data is read from each sensor, and based on the measured data, a health diagnosis is performed on the weighing sensor to obtain sensor health indicators; the measured data includes measured thrust, measured displacement, and measured reaction force.

[0009] Based on sensor health indicators, the measured reaction force is corrected to obtain the soft measurement reaction force. Based on sensor health indicators, the soft measurement reaction force and the theoretical reaction force are weighted and summed to obtain the fused reaction force.

[0010] Based on the fusion reaction force and the measured thrust, the estimated value of the friction coefficient is calculated, and based on the change in the center of gravity position, the estimated value of the friction coefficient and the fusion reaction force, the feedforward thrust is calculated.

[0011] Based on the feedforward thrust and the measured displacement, PID feedback correction is performed to obtain the feedback correction amount; the feedback correction amount is used to instruct the actuator to perform deviation correction actions.

[0012] Furthermore, based on the sensor's health indicators, the measured reaction force is corrected to obtain the soft-measurement reaction force, including:

[0013] Based on the measured displacement, the original velocity of the current cycle is calculated, and based on the acceleration of the previous cycle, the original velocity, and the duration of the control cycle, the smoothed acceleration of the current cycle is calculated.

[0014] If the sensor health indicator is abnormal, the equivalent mass, damping coefficient, and track slope angle are obtained. Based on the smooth acceleration, equivalent mass, damping coefficient, and track slope angle, the original soft measurement reaction force estimate is calculated, and the original soft measurement reaction force estimate is corrected for reasonableness to obtain the soft measurement reaction force.

[0015] If the sensor health indicator is normal, then the measured reaction force is set to the soft measurement reaction force;

[0016] The formula for calculating smooth acceleration is as follows:

[0017] ;

[0018] in, For a smooth acceleration with period t, These are the weighting coefficients. The initial acceleration with period t, The acceleration has a period of t-1.

[0019] Furthermore, the original soft-sensor reaction force estimate is corrected for reasonableness to obtain the soft-sensor reaction force, including:

[0020] Based on the original soft-sensor reaction force estimate, a negative value test is performed to obtain a negative soft-sensor reaction force estimate. The negative soft-sensor reaction force estimate is then clamped to zero to obtain a non-negative clamping reaction force value.

[0021] Based on the preset rated bearing capacity, the upper limit of the non-negative clamping reaction force value is cut off to obtain the upper limit cut-off reaction force value;

[0022] Based on the reasonable soft measurement reaction force value of the previous cycle, the relative change rate of the upper limit cutoff reaction force value relative to the rated bearing capacity is calculated, and abrupt change test is performed based on the relative change rate to obtain the abrupt change test result.

[0023] If the mutation test result is true, then based on the rated bearing capacity and the reasonable soft measurement reaction force value of the previous cycle, calculate the mutation replacement value and set the mutation replacement value as the soft measurement reaction force;

[0024] If the mutation test result is false, the upper limit cutoff reaction force value is set to the soft measurement reaction force.

[0025] Furthermore, based on smooth acceleration, equivalent mass, damping coefficient, and track slope angle, the estimated values ​​of the original soft-sensor reaction forces are calculated, including:

[0026] The formula for calculating the original soft-sensor reaction force estimate is as follows:

[0027]

[0028] in, This is the original soft-sensor reaction force estimate. For effective thrust, For equivalent quality, The acceleration is along the slip direction. This is the equivalent viscous damping coefficient. For speed, It is the acceleration due to gravity. Slope projection factor is the estimated friction coefficient for the previous cycle, and i is the index of the weighing sensor.

[0029] Furthermore, based on the combined reaction force and the measured thrust, the estimated value of the friction coefficient is calculated, including:

[0030] The apparent friction coefficient is calculated based on the combined reaction force and the measured thrust.

[0031] Based on the friction coefficient estimate and apparent friction coefficient of the previous period, residual calculation is performed to obtain residual values. Based on the residual values ​​and the preset residual threshold, abrupt change detection is performed to obtain abrupt change flags.

[0032] Based on the mutation marker, the forgetting factor and covariance matrix are obtained, and based on the residual value, forgetting factor and covariance matrix, recursive least squares update is performed to obtain the temporary friction coefficient estimate.

[0033] The temporary friction coefficient estimate is physically limited to obtain the physically limited friction coefficient, and the rate of change of the physically limited friction coefficient is limited to obtain the friction coefficient estimate for this period.

[0034] Furthermore, based on the change in center of gravity, the estimated friction coefficient, and the fusion reaction force, the feedforward thrust is calculated, including:

[0035] The formula for calculating the feedforward thrust is as follows:

[0036] ;

[0037] in, Here, i represents the feedforward thrust value, and i is the load cell index. This is an estimated value for the coefficient of friction. To integrate reaction force values, For the center of gravity shift compensation item, For safety bias;

[0038] The formula for calculating the center of gravity shift compensation term is as follows:

[0039] ;

[0040] in, For the center of gravity shift compensation item, To compensate for the gain, To incorporate the sensitivity of reaction force to the position of the center of gravity, This represents the change in the position of the center of gravity. This is the arithmetic mean of the estimated friction coefficients.

[0041] Secondly, this application also provides a real-time correction device for cumulative sliding construction positioning deviation of a large-span steel structure roof, comprising:

[0042] The theoretical module is used to obtain the mass and centroid coordinates of the assembled vehicle, and based on the mass and centroid coordinates of the assembled vehicle, to calculate the change in the center of gravity position and the theoretical reaction force;

[0043] The diagnostic module is used to read measured data from each sensor and perform health diagnosis on the weighing sensor based on the measured data to obtain sensor health indicators; the measured data includes measured thrust, measured displacement and measured reaction force;

[0044] The fusion module is used to correct the measured reaction force based on sensor health indicators to obtain the soft measurement reaction force, and to obtain the fused reaction force by weighted summation of the soft measurement reaction force and the theoretical reaction force based on sensor health indicators.

[0045] The thrust module is used to calculate the friction coefficient estimate based on the fused reaction force and the measured thrust, and to calculate the feedforward thrust based on the change in center of gravity position, the friction coefficient estimate, and the fused reaction force.

[0046] The correction module is used to perform PID feedback correction based on the feedforward thrust and the measured displacement to obtain the feedback correction amount; wherein, the feedback correction amount is used to instruct the actuator to perform deviation correction action.

[0047] Thirdly, this application also provides a computer device including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement any step of the method provided in the first aspect of this application.

[0048] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any step of the method provided in the first aspect of this application.

[0049] The aforementioned method for real-time correction of cumulative sliding construction positioning deviation in large-span steel structure roofs involves acquiring the mass and centroid coordinates of the assembled frame, and calculating the change in center of gravity position and theoretical reaction force based on these coordinates. Measured data is read from various sensors, and a health check is performed on the weighing sensors based on this data to obtain sensor health indicators. The measured data includes measured thrust, measured displacement, and measured reaction force. Based on the sensor health indicators, the measured reaction force is corrected to obtain a soft-measured reaction force. Then, based on the sensor health indicators, the soft-measured reaction force and theoretical reaction force are weighted and summed to obtain a fused reaction force. Based on the fused reaction force and measured thrust, an estimated friction coefficient is calculated. Finally, based on the change in center of gravity position, the estimated friction coefficient, and the fused reaction force, a feedforward thrust is calculated. Based on the feedforward thrust and measured displacement, PID feedback correction is performed to obtain a feedback correction amount. This feedback correction amount is used to instruct the actuator to perform deviation correction actions. It can incorporate the theoretical reaction force changes caused by the shift in the center of gravity, avoiding initial deviations caused by excessive thrust at the front support points and insufficient thrust at the rear support points due to the rearward shift of the center of gravity; it can introduce soft measurement inversion to increase the weight of theoretical reaction force to maintain control continuity, avoid the entire line shutdown caused by the failure of a single sensor, and improve the efficiency of project schedule assurance; it can introduce friction coefficient calculation to reduce the error of feedforward thrust, reduce the non-design load on the structure during the sliding process, and avoid adverse effects on the service performance of the permanent structure. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0051] Figure 1 This is a schematic diagram of the process for real-time correction of cumulative sliding construction positioning deviation of a large-span steel structure roof according to an embodiment of the present invention.

[0052] Figure 2 This is a schematic diagram of the structure of a real-time correction device for cumulative sliding construction positioning deviation of a large-span steel structure roof provided in an embodiment of the present invention. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0054] In one embodiment, such as Figure 1 As shown, a method for real-time correction of cumulative sliding construction positioning deviation for large-span steel structure roofs is provided. This embodiment illustrates the application of this method to a terminal. It is understood that this method can also be applied to a server, and to a system including both a terminal and a server, and implemented through interaction between the terminal and the server. In this embodiment, the method includes the following steps:

[0055] Step 101: Obtain the mass and centroid coordinates of the assembled vehicle, and calculate the change in center of gravity and theoretical reaction force based on the mass and centroid coordinates of the assembled vehicle.

[0056] The assembled unit mass refers to the total mass of all roof structural units that have been assembled on the sliding frame as of the current moment. This mass includes the weight of the main trusses, secondary trusses, node connectors, and installed auxiliary components. It is a scalar value, usually expressed in tons or kilograms, and is derived from the accumulation of the BIM model according to the assembly sequence or the output of the construction simulation system.

[0057] Centroid coordinates refer to the three-dimensional center of mass of the assembled frame. In a sliding coordinate system, the centroid coordinates are typically plotted with the sliding direction as the X-axis, the lateral direction as the Y-axis, and the vertical direction as the Z-axis. These coordinates are obtained by weighted averaging of the center of mass of each frame, reflecting the geometric center of the overall roof mass distribution. The X-axis coordinate determines the longitudinal reaction force distribution ratio of each sliding shoe, while the Y-axis coordinate determines the lateral eccentric loading.

[0058] The change in center of gravity position refers to the offset of the centroid coordinates calculated in the current control cycle relative to the previous control cycle. This offset typically includes components in the X and Y directions, reflecting the degree of change in the roof mass distribution caused by factors such as the assembly of a new hull or deformation of an existing hull. It serves as the basis for compensating for the shift in the center of gravity in subsequent feedforward thrust calculations.

[0059] The theoretical reaction force refers to the vertical reaction force that each skid shoe should theoretically bear, calculated according to the static force distribution principle based on the total assembled mass, centroid coordinates, and spatial arrangement of each skid shoe. This reaction force is a vector, with the number of elements equal to the number of skid shoes. The theoretical reaction force represents the force benchmark of each shoe under ideal support conditions, and is used for subsequent comparison with measured reaction forces and as an anchor value for the fusion reaction force.

[0060] The terminal retrieves the number of currently assembled frames from the construction management database or BIM model, and then obtains the corresponding total mass and centroid coordinates of the assembled frames. An update is triggered after each new frame is assembled, or the data is re-read at the beginning of each control cycle to ensure timeliness. The terminal compares the currently obtained centroid coordinates with the centroid coordinates saved in the previous control cycle, calculating the difference between the two, i.e., the change in the center of gravity position. If no new frames are assembled in the current cycle, this change should be zero or a very small value; if new frames are assembled, the change will have a significant step. The terminal performs a validity check on this change, including determining whether it exceeds a reasonable physical range to prevent data errors from causing subsequent calculation anomalies. Using the total assembled mass and centroid coordinates, combined with the fixed positions of each slipper on the slip track, the terminal calculates the theoretical reaction force of each slipper using a static distribution model. A common distribution principle is to treat the total mass as a concentrated load acting at the centroid, distributing the vertical force inversely proportional to the longitudinal distance of each slipper to the centroid, while also considering the influence of lateral eccentric loads. For statically indeterminate cases involving multiple tracks and boots, a simplified stiffness distribution method can be used. The basic idea is to ensure that the sum of the theoretical reaction forces of all boots is equal to the total assembled mass multiplied by the gravitational acceleration.

[0061] Step 102: Read the measured data from each sensor and perform a health diagnosis on the weighing sensor based on the measured data to obtain the sensor health indicator; wherein, the measured data includes measured thrust, measured displacement and measured reaction force.

[0062] Specifically, the measured thrust refers to the horizontal thrust obtained by converting the hydraulic pressure value measured by the hydraulic pressure sensor in the jacking cylinder corresponding to each slip shoe. The conversion process takes into account the effective working area of ​​the cylinder and the mechanical efficiency of the hydraulic system, representing the actual horizontal driving force applied by the cylinder to the slip shoe.

[0063] The measured displacement refers to the actual distance that each sliding shoe moves in the sliding direction. It is directly measured by displacement sensors installed on the sliding shoe or slide rail, such as wire encoders, magnetic scales, laser displacement gauges, etc. The measured displacement is a direct physical quantity that reflects the sliding process and is also the controlled variable of PID feedback control.

[0064] The measured reaction force refers to the vertical pressure value measured by the load cell installed under each sliding shoe. This sensor is usually located between the sliding shoe base plate and the slide rail, and directly bears the vertical load transmitted from the roof through the sliding shoe. The measured reaction force is first-hand data reflecting the actual stress condition of each shoe.

[0065] A sensor health indicator is a status label assigned to each load cell based on a series of diagnostic rules. This indicator is typically categorized as normal, questionable, or failed. Normal indicates that the sensor is operating reliably and the measured values ​​are reliable; questionable indicates that the sensor may have slight drift or interference, but it can still be used although its reliability should be reduced; failed indicates that the sensor is completely unreliable and its measured values ​​should no longer be used. The determination of this indicator is based on statistical results from multiple consecutive control cycles to avoid misjudgment.

[0066] During each control cycle, the terminal synchronously collects data from the hydraulic pressure sensors, displacement sensors, and load cells of all slip shoes. The collected raw signals undergo necessary filtering to remove isolated outliers, yielding the measured thrust, displacement, and reaction force for each slip shoe. The terminal then initiates a health check for the load cells, running multiple criteria in parallel. Each criterion generates a temporary anomaly flag. The results of these criteria are combined using a sliding window mechanism. If an anomaly flag appears several times consecutively, the sensor's health status is downgraded from normal to suspicious; if it appears several more times consecutively, it is further downgraded to failed. Similarly, after the anomaly disappears and the sensor returns to normal several times consecutively, the health status can gradually recover. A hysteresis mechanism prevents frequent state switching caused by occasional interference.

[0067] For example, common criteria include:

[0068] The measured reaction force is compared with the theoretical reaction force. If the ratio of the absolute value of the deviation between the two to the theoretical reaction force exceeds a preset threshold and continues for multiple cycles, an anomaly flag is triggered. The measured reaction forces of two sliding shoes at symmetrical positions within the same span are compared. If the difference is too large and the theoretical reaction forces indicate that they should be close to equal, it is determined that at least one sensor is abnormal. Consistency analysis is performed on the measured reaction force, measured thrust, and acceleration derived from measured displacement. If the ratio of thrust to reaction force is found to exceed the reasonable range of the friction coefficient, and other factors are ruled out, the reaction force sensor is suspected to be faulty. The signal characteristics of the sensor itself are monitored, such as whether the reading remains unchanged for a long time, whether there is a sudden large jump, whether it exceeds the range, and whether there are hardware failures such as communication timeouts or disconnections.

[0069] Step 103: Based on the sensor health indicators, the measured reaction force is corrected to obtain the soft measurement reaction force. Based on the sensor health indicators, the soft measurement reaction force and the theoretical reaction force are weighted and summed to obtain the fused reaction force.

[0070] Specifically, soft-measurement reaction force is a substitute vertical reaction force indirectly calculated through a dynamic model when the load cell of a sliding shoe is determined to be unhealthy. Instead of directly using the measured reaction force, this substitute value is calculated using information such as the shoe's measured thrust, measured displacement and its derivative, distributed equivalent mass, damping coefficient, track gradient, and the estimated friction coefficient from the previous cycle. The unit of soft-measurement reaction force is the same as that of the measured reaction force; it is a virtual measurement value used to maintain continuous operation of the control system in the event of sensor failure.

[0071] The fused reaction force is the reaction force value obtained by linearly combining the soft-measured reaction force and the theoretical reaction force for each slip shoe according to certain weights. The magnitude of the weights depends on the sensor health status of the slip shoe: the better the health status, the higher the weight of the soft-measured reaction force, and the theoretical reaction force only plays a fine-tuning role; the worse the health status, the lower the weight of the soft-measured reaction force and the higher the weight of the theoretical reaction force, in order to use structural mechanics knowledge to compensate for the missing information from the sensors. The fused reaction force is the reaction force value subsequently used for friction coefficient estimation and feedforward thrust calculation.

[0072] The terminal iterates through each slip shoe, selecting different paths based on its sensor health indicators to obtain the soft-measurement reaction force. If the health indicator is normal, the soft-measurement reaction force is directly equal to the measured reaction force of that shoe. In this case, the sensor is considered reliable, and the dynamic model is not required. If the health indicator is questionable or malfunctioning, the dynamic model is used to calculate the soft-measurement reaction force. This involves subtracting the equivalent mass allocated to the shoe multiplied by the acceleration along the slip direction obtained by two differentials and smoothing, the damping coefficient multiplied by the velocity of the current cycle, and then subtracting the equivalent mass multiplied by the gravitational acceleration multiplied by the sine of the track slope angle. The difference is then divided by the friction coefficient estimate from the previous cycle to deduce the vertical reaction force. Essentially, the calculation starts from the physical relationship that the remaining part after subtracting the inertial force, damping force, and slope component from the thrust is friction, and the reaction force is solved. After obtaining the original soft-measurement reaction force estimate, the terminal performs a series of rationality corrections to ensure the output value is physically reasonable. The estimated value is compared with the reasonable soft-sensor reaction force value from the previous control cycle, and their relative change is calculated. If the change exceeds a preset abrupt change threshold, the estimated value is considered to have undergone an unreasonable abrupt change. In this case, the estimated value is not used directly, but replaced by a substitute value. The substitute value is usually a combination of the rated bearing capacity and the reasonable value from the previous cycle to ensure the continuity of the output. The corrected value is the soft-sensor reaction force. For each slip shoe, the terminal obtains the weighting coefficient by looking up its sensor health indicator in a table. For example, when the health indicator is normal, the soft-sensor reaction force weight can be 0.9, and the theoretical reaction force weight can be 0.1; when the indicator is suspicious, the soft-sensor reaction force weight can be 0.7, and the theoretical reaction force weight can be 0.3; when the indicator is failed, the soft-sensor reaction force weight can be 0.4, and the theoretical reaction force weight can be 0.6. The soft-sensor reaction force is multiplied by the weight, and the theoretical reaction force is multiplied by the weight to obtain the fused reaction force.

[0073] Step 104: Based on the fusion reaction force and the measured thrust, the estimated value of the friction coefficient is calculated, and based on the change in the center of gravity position, the estimated value of the friction coefficient and the fusion reaction force, the feedforward thrust is calculated.

[0074] Specifically, the friction coefficient estimate refers to the equivalent friction coefficient between each sliding shoe and its rail contact surface. This coefficient is dimensionless, typically between 0.03 and 0.15, and reflects the frictional characteristics of the sliding pair. Because the wear, lubrication, and surface cleanliness of the PTFE plates in each shoe vary, this coefficient needs to be estimated independently for each shoe. The friction coefficient estimate is a parameter that changes slowly over time and is continuously updated using a recursive algorithm.

[0075] Feedforward thrust refers to the baseline horizontal thrust value that is pre-calculated before the start of each control cycle, based on currently known model parameters and state information, and is expected to be applied to each slip shoe cylinder. This value serves as the basis for subsequent PID feedback correction. The calculation of feedforward thrust comprehensively considers frictional resistance, additional resistance caused by changes in the center of gravity, and necessary safety margins, aiming to allow the cylinder to output a force close to the actual demand before feedback intervention, thereby reducing the burden on feedback control and improving response speed and accuracy.

[0076] The terminal uses the measured thrust and the combined reaction force of each slip shoe in the current cycle to calculate the estimated friction coefficient of that shoe through mathematical processing. The basic principle is that in horizontal slip motion, the thrust provided by the cylinder is mainly used to overcome the friction on the slip surface, and the magnitude of the friction is equal to the friction coefficient multiplied by the vertical reaction force. Therefore, by comparing the measured thrust and the combined reaction force, the friction coefficient can be deduced. The measured thrust is not simply divided by the combined reaction force to obtain the friction coefficient, because the measured thrust also includes contributions from other components such as acceleration inertia force and damping force. The terminal employs a recursive or filtering algorithm, combining historical data and current observations, to gradually approximate the true friction coefficient, suppressing measurement noise interference and possessing the ability to track slow changes in the friction coefficient. The terminal uses the estimated friction coefficient, the change in center of gravity position, and the combined reaction force to calculate the feedforward thrust of each slip shoe. The terminal multiplies the estimated friction coefficient by the combined reaction force to obtain the basic thrust component. The basic thrust component represents the basic thrust required to overcome slip friction under the assumption of no change in the center of gravity and no other additional resistance. Since the friction coefficient is estimated for each shoe, the basic thrust also reflects the differences in the friction characteristics of each shoe. The terminal considers the impact of changes in the center of gravity position. When the centroid of the assembled roof moves, the vertical reaction force distribution of each slip shoe changes, which in turn causes the thrust required by each shoe to change. The terminal uses the change in the center of gravity position, combined with the sensitivity relationship reflecting the change in the reaction force of each shoe when the centroid moves a unit distance, to calculate the compensation thrust component. The role of the compensation component is to incorporate the additional resistance caused by the movement of the center of gravity into the feedforward thrust in advance, so that the hydraulic cylinder can actively adapt to the change in mass distribution, rather than passively waiting for feedback to correct it. The components are added together to obtain the feedforward thrust of each slip shoe.

[0077] Step 105: Based on the feedforward thrust and the measured displacement, perform PID feedback correction to obtain the feedback correction amount; wherein, the feedback correction amount is used to instruct the actuator to perform deviation correction action.

[0078] The feedback correction refers to the additional thrust value that the PID controller calculates based on the deviation between the measured displacement and the desired displacement of each slipper, which needs to be added to the feedforward thrust. This correction is measured in kilonewtons (kN) and can be positive or negative; a positive value indicates an increase in thrust, and a negative value indicates a decrease in thrust. It is used to eliminate residual deviations that the feedforward could not fully compensate for, such as position deviations caused by factors like friction coefficient estimation errors, wind load disturbances, local unevenness of the slide rail, and synchronization misalignment of the slippers.

[0079] The actuator refers to the hydraulic jacking system corresponding to each slip shoe, mainly including a jacking cylinder, a proportional servo valve or proportional relief valve, a hydraulic pump station, and related pipelines. The actuator receives the thrust command and converts it into the actual output force of the cylinder, thereby pushing the slip shoe to move along the slide rail.

[0080] Deviation correction refers to the actual action taken by the actuator based on the feedback correction amount. Specifically, it manifests as an adjustment of the proportional valve opening, which changes the cylinder pressure accordingly, thereby increasing or decreasing the thrust of the sliding shoe, causing the measured displacement to move closer to the desired displacement and eliminating position deviation.

[0081] The terminal acquires the measured displacement of each sliding shoe in the current cycle and obtains the expected displacement of that shoe at the current moment from the motion planning module. The expected displacement is typically generated in real-time by the central control system based on the sliding velocity curve and the synchronization relationship between the shoes. For example, all shoes should reach the same cumulative displacement value at each moment to ensure the roof slides smoothly. The terminal calculates the position deviation of each sliding shoe, which is the expected displacement minus the measured displacement. This deviation can be positive or negative. The terminal independently runs a PID control algorithm for each sliding shoe. The PID controller calculates the feedback correction amount based on the current position deviation, the integral of the deviation, and the derivative of the deviation, using a proportional-integral-derivative combination. To suppress noise, the derivative term is usually filtered or disabled; upper and lower limits are set for the integral term to prevent integral saturation. The proportional gain, integral time, and derivative time of the PID need to be tuned during the commissioning phase based on the system response characteristics. After obtaining the feedback correction amount, the terminal adds it to the feedforward thrust to form the thrust command. The command also needs to undergo output limiting processing to ensure that its thrust is neither lower than the minimum starting pressure of the hydraulic cylinder nor higher than the rated thrust of the hydraulic cylinder, thus ensuring that the actuator operates within a safe range. The terminal sends the thrust command to the actuator of the corresponding slip shoe. The actuator adjusts the opening of the proportional valve or directly sets the hydraulic pressure to make the hydraulic cylinder output the corresponding thrust, driving the slip shoe to move, thereby completing the deviation correction action. At this point, a complete control cycle ends.

[0082] This embodiment provides a real-time correction method for cumulative sliding construction positioning deviation of a large-span steel structure roof. It acquires the mass and centroid coordinates of the assembled frame, and calculates the change in center of gravity position and theoretical reaction force based on these coordinates. It reads measured data from various sensors and performs a health check on the weighing sensors based on this data to obtain sensor health indicators. The measured data includes measured thrust, measured displacement, and measured reaction force. Based on the sensor health indicators, the measured reaction force is corrected to obtain a soft-measurement reaction force. Then, based on the sensor health indicators, the soft-measurement reaction force and theoretical reaction force are weighted and summed to obtain a fused reaction force. Based on the fused reaction force and measured thrust, an estimated friction coefficient is calculated. Finally, based on the change in center of gravity position, the estimated friction coefficient, and the fused reaction force, a feedforward thrust is calculated. Based on the feedforward thrust and measured displacement, PID feedback correction is performed to obtain a feedback correction amount. This feedback correction amount is used to instruct the actuator to perform deviation correction actions. By employing the above methods, we can introduce the theoretical reaction force change caused by the shift in the center of gravity, thus avoiding the initial deviation caused by excessive thrust at the front support points and insufficient thrust at the rear support points due to the rearward shift of the center of gravity; by introducing soft measurement inversion, we can increase the weight of the theoretical reaction force to maintain control continuity, avoid the entire line shutdown caused by the failure of a single sensor, and improve the efficiency of project schedule assurance; by introducing friction coefficient calculation, we can reduce the error of feedforward thrust, reduce the non-design load on the structure during the sliding process, and avoid adverse effects on the service performance of the permanent structure.

[0083] In one embodiment, the measured reaction force is corrected based on sensor health indicators to obtain a soft-measurement reaction force, including:

[0084] Step 201: Based on the measured displacement, calculate the original velocity of the current cycle, and based on the acceleration, original velocity and control cycle duration of the previous cycle, calculate the smoothed acceleration of the current cycle.

[0085] The formula for calculating smooth acceleration is as follows:

[0086] ;

[0087] in, For a smooth acceleration with period t, These are the weighting coefficients. The initial acceleration with period t, The acceleration has a period of t-1.

[0088] The raw velocity of the current cycle refers to the instantaneous velocity of the current cycle calculated by dividing the difference between the measured displacement of the current cycle and the measured displacement of the previous cycle by the control cycle duration. This velocity is not smoothed and directly reflects the rate of change of displacement, thus it is easily affected by displacement measurement noise.

[0089] The acceleration of the previous cycle refers to the acceleration value saved at the end of the previous control cycle. This value can be the smoothed acceleration of the previous cycle or the original acceleration of the previous cycle, depending on the storage strategy. In this embodiment, it is used as a historical reference value for smoothing calculations.

[0090] The control cycle duration refers to the time interval between two adjacent control cycles. It is a fixed constant, usually measured in seconds or milliseconds. It is used to convert displacement difference into velocity, and subsequent velocity difference into acceleration.

[0091] The raw acceleration for the current cycle is calculated by dividing the difference between the raw velocity of the current cycle and the raw velocity of the previous cycle by the control cycle duration. It has not undergone any smoothing and therefore has a high noise level.

[0092] Smoothed acceleration refers to the acceleration value of the current period obtained by performing an exponentially weighted moving average of the original acceleration. It is calculated by mixing the original acceleration of the current period with the smoothed acceleration of the previous period in a certain proportion, so that the change in acceleration is smoother and measurement noise and differential amplification effects are suppressed.

[0093] The weighting coefficient is a constant between 0 and 1, used to control the speed at which the smoothed acceleration follows the original acceleration and the degree of filtering. The closer the coefficient is to 1, the more the smoothed acceleration follows the original acceleration, resulting in a fast response but weak noise suppression; the closer the coefficient is to 0, the more the smoothed acceleration depends on historical values, resulting in a slow response but strong noise suppression.

[0094] The terminal acquires the measured displacement of each slip shoe in the current cycle and reads the measured displacement saved in the previous cycle. The measured displacement of the current cycle is subtracted from the measured displacement of the previous cycle to obtain the displacement increment. This increment is then divided by the control cycle duration to obtain the raw velocity of the current cycle. The terminal acquires the raw velocity or smoothed velocity saved in the previous cycle. The raw velocity of the current cycle is subtracted from the raw velocity of the previous cycle to obtain the velocity increment. This increment is then divided by the control cycle duration to obtain the raw acceleration of the current cycle. The terminal performs smoothed acceleration calculation, reading the smoothed acceleration saved in the previous cycle and the preset weighting coefficient. The raw acceleration of the current cycle is multiplied by the weighting coefficient, and then the sum of the smoothed acceleration of the previous cycle multiplied by 1 and subtracted from the weighting coefficient is added. The result is the smoothed acceleration of the current cycle, which is equivalent to low-pass filtering the raw acceleration, preserving low-frequency trends and suppressing high-frequency noise. The terminal stores the smoothed acceleration, raw velocity, and raw acceleration data of the current cycle into memory for use in the next control cycle.

[0095] The formula mixes the raw acceleration of the current cycle with the smoothed acceleration of the previous cycle in a fixed ratio, ensuring that the output smoothed acceleration both follows the trend of the raw acceleration and suppresses measurement noise and high-frequency jitter caused by differential amplification. The weighting coefficient determines the strength of the filter: the closer the coefficient is to 1, the more closely the smoothed acceleration follows the raw acceleration, resulting in a fast response but weak noise suppression; the closer the coefficient is to 0, the more the smoothed acceleration relies on historical values, resulting in a smoother curve but a slower response. The weighting coefficient can be tuned based on the noise level of the displacement sensor and the required dynamic response speed of the system.

[0096] Step 202: If the sensor health indicator is abnormal, obtain the equivalent mass, damping coefficient and track slope angle. Based on the smooth acceleration, equivalent mass, damping coefficient and track slope angle, calculate the original soft measurement reaction force estimate and make a reasonable correction to the original soft measurement reaction force estimate to obtain the soft measurement reaction force.

[0097] Specifically, equivalent mass refers to the equivalent mass value allocated to the current slip shoe for use in horizontal dynamics calculations. This mass is not the roof mass directly borne by the shoe, but rather the inertial mass allocated to the shoe based on the overall mass distribution and structural stiffness of the roof. The unit is usually tons or kilograms, and it reflects the magnitude of the inertial force that the shoe needs to overcome during horizontal acceleration.

[0098] The damping coefficient refers to the equivalent viscous damping coefficient provided by the sliding contact surface and the sliding shoe guide device, reflecting the magnitude of the resistance that is proportional to the speed during the sliding process.

[0099] The track slope angle refers to the angle of inclination of the sliding track relative to the horizontal plane, usually measured in degrees or radians. If the track is perfectly horizontal, this angle is zero; if there is a slope, the effect of the component of gravity along the track direction on the thrust must be considered. This angle is usually predetermined by construction surveying and stored in the system.

[0100] The original soft-sensor reaction force estimate refers to the preliminary value of the vertical reaction force derived from the thrust, inertial force, damping force, and ramp component using the dynamic equations when the load cell is unreliable. This value has not been rationally corrected and may contain negative, out-of-limit, or abrupt values, therefore it cannot be used directly.

[0101] Soft-sensor reaction force refers to the vertical reaction force substitute value obtained after a series of reasonable corrections to the original soft-sensor reaction force estimate, which can be used for subsequent fusion calculations. It is the best estimate of the true reaction force under sensor failure conditions.

[0102] The terminal determines whether the current skid shoe's sensor health indicators are normal. If not, it enters the soft-sensor calculation branch, retrieving the equivalent mass, damping coefficient, and track slope angle pre-configured for the skid shoe from memory. Simultaneously, it acquires the smoothed acceleration of the current cycle, the measured thrust of the current cycle, the estimated friction coefficient of the previous cycle, and the velocity of the current cycle. The terminal calculates the raw soft-sensor reaction force estimate. The basic logic is to subtract the equivalent mass multiplied by the smoothed acceleration, the damping coefficient multiplied by the velocity of the current cycle, and the equivalent mass multiplied by the gravitational acceleration multiplied by the sine of the track slope angle from the measured thrust of the current cycle. The difference is then divided by the estimated friction coefficient of the previous cycle to obtain a preliminary estimate of the vertical reaction force. The physical meaning of this calculation process is that after deducting acceleration, damping, and slope consumption, the remaining thrust is entirely used to overcome friction. Since the friction force is equal to the friction coefficient multiplied by the vertical reaction force, the reaction force can be derived by division. After obtaining the original soft-sensor reaction force estimate, the terminal performs a reasonable correction to obtain the soft-sensor reaction force of the slip shoe in this cycle.

[0103] Step 203: If the sensor health indicator is normal, then set the measured reaction force to the soft measurement reaction force.

[0104] The terminal determines whether the current slip shoe's sensor health indicator is normal. If so, it skips the calculation process in step 202 and directly assigns the measured reaction force of the shoe to the soft-measurement reaction force. In other words, the soft-measurement reaction force equals the measured reaction force at this point, requiring no correction or substitution. When the load cell is functioning normally, its measured value is considered the most direct and accurate source of vertical reaction force information, eliminating the need for complex dynamic models. This avoids additional deviations caused by model errors and parameter uncertainties.

[0105] In one embodiment, the original soft-sensor reaction force estimate is rationally corrected to obtain the soft-sensor reaction force, including:

[0106] Step 301: Based on the original soft-sensor reaction force estimate, perform a negative value test to obtain a negative soft-sensor reaction force estimate, and clamp the negative soft-sensor reaction force estimate to zero to obtain a non-negative clamped reaction force value.

[0107] In the process of performing negative value testing, if the original soft measurement reaction force estimate is less than zero, it is called a negative soft measurement reaction force estimate and is used to identify negative values ​​that need to be clamped.

[0108] The non-negative clamping reaction force value is the result obtained by applying a negative clamping process to the original soft-sensor reaction force estimate. If the original estimate is negative, it is forced to zero; if the original estimate is non-negative, the original value is retained to ensure that the reaction force used in subsequent calculations will not be negative, which is consistent with physical facts.

[0109] The terminal acquires the original soft-sensor reaction force estimate of the current slip shoe. The terminal performs a negative check on this value: determining if it is less than zero. If it is less than zero, the terminal marks it as a negative soft-sensor reaction force estimate and performs a clamping operation, modifying the value to zero to obtain a non-negative clamping reaction force value. If the original estimate is greater than or equal to zero, no modification is performed, and the original estimate is directly used as the non-negative clamping reaction force value.

[0110] Step 302: Based on the preset rated bearing capacity, the upper limit of the non-negative clamping reaction force value is cut off to obtain the upper limit cut-off reaction force value.

[0111] Specifically, the preset rated load capacity is a maximum permissible vertical reaction force value pre-set for each slip shoe, determined by the structural strength of the slip shoe and the allowable stress of the rail material. Exceeding this value may cause permanent deformation or damage to the slip shoe or rail; therefore, no reaction force value may exceed this upper limit.

[0112] The upper limit cutoff reaction force value is the value obtained by cutting off the upper limit of the non-negative clamping reaction force value. If the non-negative clamping reaction force value is greater than the rated bearing capacity, it is cut off to the rated bearing capacity; if the non-negative clamping reaction force value is not greater than the rated bearing capacity, the original value is retained. This value ensures that the reaction force value is always within a safe range.

[0113] Step 303: Based on the reasonable soft measurement reaction force value of the previous cycle, calculate the relative change rate of the upper limit cutoff reaction force value relative to the rated bearing capacity, and perform a mutation test based on the relative change rate to obtain the mutation test result.

[0114] Specifically, the reasonable soft-sensor reaction force value of the previous cycle is the soft-sensor reaction force value determined and stored in the previous control cycle. It represents the reaction force value recognized by the slip shoe at the previous moment and serves as a reference benchmark for measuring whether the current reaction force has undergone a sudden change.

[0115] The relative rate of change is the ratio of the absolute value of the difference between the upper limit cutoff reaction force value and the reasonable soft-measurement reaction force value of the previous period, divided by the rated bearing capacity. This ratio is a dimensionless number, reflecting the magnitude of the change in the current reaction force relative to the rated bearing capacity. The rated bearing capacity is chosen as the denominator because it is a fixed reference scale, facilitating the standardization of threshold values.

[0116] The mutation test result is a Boolean value, either true or false. It is obtained by comparing the relative rate of change with a preset mutation threshold. If the relative rate of change is greater than the mutation threshold, the current reaction force is determined to have undergone an unreasonable mutation, and the result is true; otherwise, the result is false. The mutation threshold is a preset constant, for example, 0.5, which means that a relative rate of change exceeding 50% is considered a mutation.

[0117] The terminal reads the reasonable soft-measured reaction force value of the slipper in the previous cycle. It calculates the absolute value of the difference between the upper limit cutoff reaction force value and the reasonable soft-measured reaction force value of the previous cycle. This absolute value is divided by the rated load capacity to obtain the relative rate of change. The terminal reads the preset mutation threshold. The relative rate of change is compared with the mutation threshold: if the relative rate of change is greater than the mutation threshold, the mutation test result is true; if the relative rate of change is less than or equal to the mutation threshold, the mutation test result is false.

[0118] Step 304: If the mutation test result is true, calculate the mutation replacement value based on the rated bearing capacity and the reasonable soft measurement reaction force value of the previous cycle, and set the mutation replacement value as the soft measurement reaction force.

[0119] The mutation substitution value is a value calculated based on the rated bearing capacity and the reasonable soft-sensor reaction force value from the previous cycle, instead of directly using the upper limit cutoff reaction force value when the mutation test result is true. The purpose of this substitution value is to avoid drastic jumps in the reaction force value and ensure the stability of the control system. The calculation rule can be either the average of the reasonable soft-sensor reaction force value from the previous cycle and the rated bearing capacity, or the reasonable soft-sensor reaction force value from the previous cycle plus a maximum allowable variation.

[0120] The soft-measured reaction force is the vertical reaction force value used in subsequent fusion calculations. If the mutation test result is true, it is set as the mutation substitute value.

[0121] After the terminal determines that the mutation test result is true, it enters the mutation processing branch. The terminal reads the rated bearing capacity and the reasonable soft measurement reaction force value of the previous cycle. It calculates the mutation replacement value according to the preset rules. After obtaining the mutation replacement value, the terminal sets it as the soft measurement reaction force of the slip shoe in the current cycle and stores it in memory for use in subsequent steps.

[0122] For example, one possible rule is to take the arithmetic mean of the reasonable soft-measurement reaction force value and the rated bearing capacity of the previous period as the abrupt change replacement value. Another possible rule is to take the reasonable soft-measurement reaction force value of the previous period plus the rated bearing capacity multiplied by a preset small coefficient, but not exceeding the rated bearing capacity. Regardless of the rule adopted, the goal is to make the abrupt change replacement value as close as possible to the reasonable value of the previous period, while not exceeding the rated bearing capacity, thereby achieving a smooth transition.

[0123] Optionally, the formula for calculating the mutation substitution value can be... ;in, To inherit weights, This is the soft-measured reaction force value from the previous cycle. This is the rated load-bearing capacity.

[0124] Step 305: If the mutation test result is false, then set the upper limit cutoff reaction force value to the soft measurement reaction force.

[0125] If the terminal determines the mutation test result to be false, it indicates that the change in the upper cutoff reaction force value relative to the reasonable value of the previous cycle is within the allowable range, and no unreasonable mutation has occurred. The terminal directly uses the upper cutoff reaction force value as the soft measurement reaction force of the slip shoe in this cycle and stores it in memory for use in subsequent steps. No additional calculations or replacements are required.

[0126] In one embodiment, the original soft-sensor reaction force estimate is calculated based on smooth acceleration, equivalent mass, damping coefficient, and track slope angle, including:

[0127] The formula for calculating the original soft-sensor reaction force estimate is as follows:

[0128]

[0129] in, This is the original soft-sensor reaction force estimate. For effective thrust, For equivalent quality, The acceleration is along the slip direction. This is the equivalent viscous damping coefficient. For speed, It is the acceleration due to gravity. Slope projection factor is the estimated friction coefficient for the previous cycle, and i is the index of the weighing sensor.

[0130] Specifically, i is the load cell index, and one slip shoe corresponds to a set of load cells, hydraulic pressure sensors and displacement sensors. Therefore, the corresponding slip shoe can be found through i.

[0131] The effective thrust is the actual horizontal pushing driving force generated by the jacking cylinder corresponding to the i-th sliding shoe in this control cycle. It is calculated from the cylinder oil pressure measured by the oil pressure sensor and is the product of oil pressure, effective bearing area of ​​the cylinder, and hydraulic mechanical efficiency coefficient.

[0132] The equivalent mass is the equivalent inertial mass allocated to the i-th sliding shoe and involved in the horizontal translational dynamics calculation. It is measured in kilograms or tons and is not equivalent to the static weight of the roof directly borne by the i-th shoe divided by gravitational acceleration. Instead, it is calculated based on the total mass of the assembled frame, the overall centroid coordinates, the spatial positions of each shoe, and the stiffness distribution of the roof in the sliding state. It represents the share of inertial mass exhibited by the i-th shoe when the entire roof moves along the sliding direction with the corresponding acceleration. It is updated as the assembly progresses; it can be considered constant between two assembly phases and during pure sliding.

[0133] The acceleration along the slip direction is the instantaneous acceleration of the i-th shoe along the slip direction in this period. The original acceleration is obtained by differential analysis of the slip stroke measured by the displacement sensor, and then smoothed by low-pass filtering through the exponential smoothing formula. This can suppress the high-frequency glitches that are amplified after the displacement measurement noise is amplified by the second differential analysis, and avoid non-physical jumps in the original soft measurement reaction force estimate.

[0134] The equivalent viscous damping coefficient is the equivalent linear viscous damping coefficient provided by the sliding contact surface of the i-th shoe and the shoe side guiding constraint. Physically, it represents the resistance component proportional to the sliding velocity, excluding the main Coulomb friction force, during the sliding process. A conservative range value is typically given offline based on the material properties of the sliding pair, the slide plate area, the lubrication state, and the guide clearance. In multi-shoe synchronous operation, if the sliding conditions of each shoe are similar, it can be simplified to a globally unified parameter.

[0135] The slope projection factor is the dimensionless sine of the longitudinal slope angle of the sliding track at the location of the i-th shoe. It is calculated from the elevation difference of the track longitudinal profile given by construction surveying, and the slope may not be exactly the same for each shoe. When the i-th shoe is on an uphill section, the component of gravity along the sliding direction is the drag, and this term is positive in the numerator; when it is on a downhill section, it is the assist, and this term is negative in the numerator; when the track is strictly horizontal, this term disappears. The slope projection factor is a read-only prior geometric parameter after the sliding path is determined and does not need to be identified online.

[0136] In one embodiment, the friction coefficient estimate is calculated based on the combined reaction force and the measured thrust, including:

[0137] Step 501: Calculate the apparent friction coefficient based on the fusion reaction force and the measured thrust.

[0138] The apparent friction coefficient refers to the ratio of the measured thrust to the combined reaction force during the current control cycle. Physically, this ratio is approximately equal to the ratio of thrust to vertical reaction force. However, since the thrust actually includes inertial forces, damping forces, and gradient components that are not completely separated, this ratio is not the true friction coefficient but rather an apparent value mixed with other components. The apparent friction coefficient is used as the observation input for the recursive estimation algorithm.

[0139] The terminal reads the combined reaction force and measured thrust value of this slipper shoe. The terminal checks the validity of both values: the combined reaction force must be greater than a very small positive number to prevent division by zero or ill-conditioned values; the measured thrust should be non-negative and within the cylinder's rated range. After passing the checks, the terminal divides the measured thrust by the combined reaction force to obtain the apparent friction coefficient for this cycle. This calculation process is independent for each slipper shoe, yielding an apparent friction coefficient value for each shoe. Because the combined reaction force already includes the anchoring component of the theoretical reaction force, and the measured thrust also contains contributions from inertia / damping / gradient, there is a systematic deviation between this apparent value and the true value, but it is reasonable as input to the observation sequence.

[0140] Step 502: Based on the estimated friction coefficient and apparent friction coefficient of the previous cycle, perform residual calculation to obtain residual value, and based on the residual value and the preset residual threshold, perform mutation detection to obtain mutation flag.

[0141] Specifically, the friction coefficient estimate of the previous cycle is the friction coefficient estimate of the slipper determined at the end of the previous control cycle. It is stored in memory as the old value for recursive updates in this cycle and as the reference benchmark for residual calculation.

[0142] The residual refers to the deviation between the apparent friction coefficient of the current period and the estimated friction coefficient of the previous period, reflecting how much the newly observed apparent value deviates from the estimated value already tracked by the model. The magnitude and direction of the residual are used to determine whether the friction coefficient has undergone a sudden change.

[0143] The preset residual threshold is a pre-defined constant representing the maximum acceptable residual magnitude. This threshold is determined based on the normal fluctuation range of the friction coefficient of the PTFE plate slippage. Exceeding this threshold indicates that the observed value does not match the model's expectations and a sudden change may have occurred.

[0144] The mutation flag is a Boolean state variable that takes the value of true or false. When the absolute value of the residual exceeds the residual threshold, the mutation flag is set to true, indicating that the friction coefficient may change abruptly; otherwise, it is set to false, indicating that the friction coefficient changes gradually and is within the normal tracking range.

[0145] The forgetting factor is an adjustable parameter in the recursive least squares algorithm, typically ranging from 0.95 to 0.999. It determines the rate at which the weight of historical data decays in the recursive update. A forgetting factor closer to 1 retains more historical data, resulting in a smoother estimate but slower mutation tracking; a factor closer to 0.95 gives greater weight to new data, leading to faster mutation tracking but larger estimation fluctuations. When a mutation flag is true, the forgetting factor is temporarily reduced to give new observations a larger weight.

[0146] The covariance matrix is ​​a matrix quantity used in recursive least squares algorithms to describe the uncertainty of parameter estimation. In the simplest case of a single-bootstrap, single-parameter model, it degenerates into a scalar. This quantity is adaptively updated during the recursive process; the covariance decreases when the observation matches the model well and increases when the observation jumps. It directly participates in the calculation of the Kalman gain, determining the extent to which new observations can correct old estimates.

[0147] The terminal reads the estimated friction coefficient and apparent friction coefficient saved in the previous cycle. The terminal subtracts the two to obtain the residual. The residual can be positive or negative; a positive residual indicates that the apparent value is larger than the estimated value in the previous cycle, while a negative residual indicates a possible decrease. The terminal reads a preset residual threshold and compares the absolute value of the residual with the threshold. If the absolute value is greater than the threshold, a mutation is considered to have occurred, and the mutation flag is set to true; otherwise, it is set to false. Judging a mutation based on a single instance of exceeding the threshold is prone to being misled by single outliers; therefore, a mutation counter can be used, setting the flag to true only after N consecutive cycles of residual exceeding the threshold and false only after M consecutive cycles of regression.

[0148] Step 503: Based on the mutation marker, obtain the forgetting factor and covariance matrix, and based on the residual value, forgetting factor and covariance matrix, perform recursive least squares update to obtain the temporary friction coefficient estimate.

[0149] Specifically, Recursive Least Squares (RLS) update is a recursive parameter identification algorithm. The core idea is that instead of batch processing all historical data from the beginning at each iteration, it uses the estimation results and uncertainties from the previous iteration, combined with the new observations and residuals of the current iteration, to update the new estimate for the current iteration using Kalman gain weighting. Compared to ordinary averaging or low-pass filtering, RLS provides more rigorous parameter tracking for linear models and can adjust its adaptability to time-varying conditions through a forgetting factor.

[0150] The temporary friction coefficient estimate refers to the friction coefficient estimate for the current period calculated by the RLS recursive update formula, which has not yet undergone amplitude limiting. It has incorporated information from historical estimates and new observations, but may still be physically unreasonable or have an excessive rate of change.

[0151] Based on the mutation flag, the terminal determines the initial values ​​of the forgetting factor and covariance matrix for the current cycle. If the mutation flag is false, the forgetting factor takes the steady-state value, and the covariance matrix takes the value saved after the update in the previous cycle. If the mutation flag is true, the forgetting factor is reduced, and the covariance matrix can be amplified by several times. The terminal reads the fusion reaction force value of the slip shoe in the current cycle as the regressor. In the case of single-parameter estimation, the recursive formula requires the regressor transpose multiplied by the covariance multiplied by the regressor, plus a small denominator term. The terminal calculates this quantity and takes its reciprocal for later use. The larger the fusion reaction force, the stronger the information provided by the observation, and the gain will be adjusted accordingly. The terminal multiplies the covariance of the previous cycle by the regressor, and then by the reciprocal obtained from the first sub-action to obtain the Kalman gain for the current cycle. The gain is a scalar between zero and one. If the covariance or fusion reaction force is large, the gain is large, and the new observation has a high weight; conversely, the gain is small, and the old estimate has a high weight. When the mutation flag is true, the gain will be significantly larger than when it is steady-state because the covariance has been amplified. The old estimate is corrected to obtain a temporary estimate. The terminal reads the friction coefficient estimate and residual value from the previous cycle. The Kalman gain is multiplied by the residual value, and the result is added to the previous cycle estimate to obtain the temporary friction coefficient estimate for the current cycle. The old estimate deviates from the new observation; the deviation is the residual. A portion of the residual is added back proportionally to the gain to obtain a new estimate closer to the true value. A larger gain results in more addition, and a smaller gain results in less addition. The terminal uses the forgetting factor, current gain, regressor, and previous cycle covariance to calculate the new covariance for the current cycle according to a recursive relationship. The inherent logic of the update rule is that if the residual for the current cycle is small, the covariance will shrink, indicating increasing confidence in the estimate; if the residual for the current cycle is large, the covariance will amplify, indicating increased uncertainty, and the gain for the next cycle will increase accordingly. After the update is completed, the covariance for the current cycle is stored in memory, overwriting the previous cycle value, to obtain the temporary friction coefficient estimate for the current cycle.

[0152] Step 504: Physically limit the estimated value of the temporary friction coefficient to obtain the physically limited friction coefficient, and then limit the rate of change of the physically limited friction coefficient to obtain the estimated value of the friction coefficient for this period.

[0153] The physical range constraint refers to limiting the temporary friction coefficient estimate to a pre-defined, physically reasonable range. The lower limit of this range can be the lower boundary of dry or slightly lubricated PTFE or stainless steel, and the upper limit can be the upper boundary of severely worn or contaminated PTFE. Values ​​exceeding this range are forcibly clamped to the nearest boundary. This prevents model errors, sensor malfunctions, or RLS transients from estimating the friction coefficient to a physically impossible range.

[0154] The physical limiting friction coefficient is the friction coefficient value obtained after physical limiting. It already meets the physical requirements, but the variation range in a single shot may still be too large, so a second layer of limiting is needed.

[0155] The rate of change limiting refers to further restricting the difference between the current value and the previous value, based on the physical limiting. A maximum permissible change per beat is preset. If the absolute value of the difference between the current physical limiting value and the previous formal estimated value exceeds this amount, it is clamped to the position of the maximum permissible change. The purpose of this step is to prevent the friction coefficient estimate from jumping too much in a single beat, causing a jump in feedforward thrust, resulting in cylinder output vibration or roof impact.

[0156] The friction coefficient estimate for this period is the official friction coefficient output for the slip shoe during this control cycle after two layers of limiting. The units are dimensionless, the values ​​fall within the physical range, and the variation per shot is controlled.

[0157] The terminal reads the temporary friction coefficient estimate, along with the preset physical lower and upper limits. It determines if the temporary estimate is less than the lower limit; if so, it raises it to the lower limit. It also determines if the estimate is greater than the upper limit; if so, it lowers it to the upper limit. If the estimate falls between the two, it remains unchanged, resulting in the physical limit friction coefficient. The terminal then reads the last saved friction coefficient estimate from the previous cycle, along with the preset maximum single-shot change. It calculates the absolute value of the difference between the physical limit value and the old value. If this absolute value does not exceed the maximum single-shot change, the physical limit value is directly used as the final estimate for this cycle; otherwise, it is clamped along the difference direction to the sum or difference of the old value and the maximum single-shot change.

[0158] In one embodiment, the feedforward thrust is calculated based on the change in center of gravity, the estimated friction coefficient, and the fused reaction force, including:

[0159] The formula for calculating the feedforward thrust is as follows:

[0160] ;

[0161] in, Here, i represents the feedforward thrust value, and i is the load cell index. This is an estimated value for the coefficient of friction. To integrate reaction force values, For the center of gravity shift compensation item, For safety bias.

[0162] Specifically, the center of gravity shift compensation term is a component in the feedforward thrust of the i-th shoe, specifically used to offset the redistribution of vertical reaction forces in each shoe caused by the change in the centroid position of the assembled frame, which in turn leads to the change in the required thrust. In large-span cumulative sliding, for each frame assembled, the centroid of the total mass of the assembled frame will move towards the assembly end by a change, causing the fusion reaction force of each sliding shoe to be redistributed according to sensitivity, thereby realizing the feedforward injection of thrust changes caused by the change in center of gravity.

[0163] The safety offset is a small, positive amount artificially added to the feedforward thrust of the i-th shoe, serving as a safety net for the uncovered portion. The static friction coefficient of the PTFE plate is higher than its dynamic friction coefficient. If the feedforward only covers the main body during the slip start, it will be insufficient to overcome static friction, causing the cylinder to suddenly jump and crawl. The safety offset can be appropriately increased during the start-up phase to ensure a smooth start. Furthermore, the safety offset helps eliminate the final few millimeters of synchronization residual when precisely positioning the device at the end of a large-span cumulative slip.

[0164] The formula for calculating the center of gravity shift compensation term is as follows:

[0165] ;

[0166] in, For the center of gravity shift compensation item, To compensate for the gain, To incorporate the sensitivity of reaction force to the position of the center of gravity, This represents the change in the position of the center of gravity. This is the arithmetic mean of the estimated friction coefficients.

[0167] The compensation gain is an adjustable gain coefficient of the center-of-gravity shift compensation term. It is dimensionless and its calibrated value can be between 0.8 and 1.2. Its function is to scale the theoretical compensation amount. A value of 1.0 indicates that the compensation is based entirely on the theoretical sensitivity; a value less than 1.0 indicates conservative compensation; and a value greater than 1.0 indicates aggressive compensation.

[0168] The sensitivity of the fusion reaction force to the center of gravity position is the partial derivative of the fusion reaction force of the i-th shoe with respect to the longitudinal coordinate of the centroid of the assembled frame. Physically, it represents how many kilonewtons the vertical reaction force of the i-th shoe changes for every 1 meter the centroid moves along the sliding direction. This sensitivity can be obtained by offline static distribution model differentiation. Since the roof stiffness and shoe position remain constant during sliding, this sensitivity can be calculated offline and created as a lookup table, which can then be directly interpolated and called online without recalculating for each frame. The sensitivity itself reflects the strength of the i-th shoe's response to the movement of the center of gravity; typically, the sensitivity of the foremost shoes is positive, while that of the rearmost shoes is negative, and the sensitivity of the symmetrical shoes within the span is similar.

[0169] The limit of the feedforward thrust is: ,in, To minimize the pressure-holding creep thrust, This is the rated upper limit thrust.

[0170] It should be understood that although the steps in the flowcharts of the embodiments described above 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 flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0171] Based on the same inventive concept, this application also provides a device for real-time correction of cumulative sliding construction positioning deviation of large-span steel structure roofs, used to implement the aforementioned method for real-time correction of cumulative sliding construction positioning deviation of large-span steel structure roofs. The solution provided by this device is similar to the solution described in the above method. Therefore, the specific limitations of one or more embodiments of the device for real-time correction of cumulative sliding construction positioning deviation of large-span steel structure roofs provided below can be found in the limitations of the method for real-time correction of cumulative sliding construction positioning deviation of large-span steel structure roofs described above, and will not be repeated here.

[0172] In one exemplary embodiment, such as Figure 2 As shown, a real-time correction device 700 for cumulative sliding construction positioning deviation of a large-span steel structure roof is provided, comprising:

[0173] Theoretical module 701 is used to obtain the mass and centroid coordinates of the assembled vehicle, and to calculate the change in the center of gravity position and the theoretical reaction force based on the mass and centroid coordinates of the assembled vehicle.

[0174] The diagnostic module 702 is used to read measured data from each sensor and perform health diagnosis on the weighing sensor based on the measured data to obtain sensor health indicators; wherein, the measured data includes measured thrust, measured displacement and measured reaction force;

[0175] The fusion module 703 is used to correct the measured reaction force based on the sensor health indicator to obtain the soft measurement reaction force, and to obtain the fused reaction force by weighted summation of the soft measurement reaction force and the theoretical reaction force based on the sensor health indicator.

[0176] The thrust module 704 is used to calculate the friction coefficient estimate based on the fused reaction force and the measured thrust, and to calculate the feedforward thrust based on the change in center of gravity position, the friction coefficient estimate, and the fused reaction force.

[0177] The correction module 705 is used to perform PID feedback correction based on the feedforward thrust and the measured displacement to obtain the feedback correction amount; wherein, the feedback correction amount is used to instruct the actuator to perform deviation correction action.

[0178] Furthermore, the fusion module 703 is also used for:

[0179] Based on the measured displacement, the original velocity of the current cycle is calculated, and based on the acceleration of the previous cycle, the original velocity, and the duration of the control cycle, the smoothed acceleration of the current cycle is calculated.

[0180] If the sensor health indicator is abnormal, the equivalent mass, damping coefficient, and track slope angle are obtained. Based on the smooth acceleration, equivalent mass, damping coefficient, and track slope angle, the original soft measurement reaction force estimate is calculated, and the original soft measurement reaction force estimate is corrected for reasonableness to obtain the soft measurement reaction force.

[0181] If the sensor health indicator is normal, then the measured reaction force is set to the soft measurement reaction force;

[0182] The formula for calculating smooth acceleration is as follows:

[0183] ;

[0184] in, For a smooth acceleration with period t, These are the weighting coefficients. The initial acceleration with period t, The acceleration has a period of t-1.

[0185] Furthermore, the fusion module 703 is also used for:

[0186] Based on the original soft-sensor reaction force estimate, a negative value test is performed to obtain a negative soft-sensor reaction force estimate. The negative soft-sensor reaction force estimate is then clamped to zero to obtain a non-negative clamping reaction force value.

[0187] Based on the preset rated bearing capacity, the upper limit of the non-negative clamping reaction force value is cut off to obtain the upper limit cut-off reaction force value;

[0188] Based on the reasonable soft measurement reaction force value of the previous cycle, the relative change rate of the upper limit cutoff reaction force value relative to the rated bearing capacity is calculated, and abrupt change test is performed based on the relative change rate to obtain the abrupt change test result.

[0189] If the mutation test result is true, then based on the rated bearing capacity and the reasonable soft measurement reaction force value of the previous cycle, calculate the mutation replacement value and set the mutation replacement value as the soft measurement reaction force;

[0190] If the mutation test result is false, the upper limit cutoff reaction force value is set to the soft measurement reaction force.

[0191] The formula for calculating the original soft-sensor reaction force estimate is as follows:

[0192] ;

[0193] in, This is the original soft-sensor reaction force estimate. For effective thrust, For equivalent quality, The acceleration is along the slip direction. This is the equivalent viscous damping coefficient. For speed, It is the acceleration due to gravity. Slope projection factor is the estimated friction coefficient for the previous cycle, and i is the index of the weighing sensor.

[0194] Furthermore, the thrust module 704 is also used for:

[0195] The apparent friction coefficient is calculated based on the combined reaction force and the measured thrust.

[0196] Based on the friction coefficient estimate and apparent friction coefficient of the previous period, residual calculation is performed to obtain residual values. Based on the residual values ​​and the preset residual threshold, abrupt change detection is performed to obtain abrupt change flags.

[0197] Based on the mutation marker, the forgetting factor and covariance matrix are obtained, and based on the residual value, forgetting factor and covariance matrix, recursive least squares update is performed to obtain the temporary friction coefficient estimate.

[0198] The temporary friction coefficient estimate is physically limited to obtain the physically limited friction coefficient, and the rate of change of the physically limited friction coefficient is limited to obtain the friction coefficient estimate for this period.

[0199] The formula for calculating the feedforward thrust is as follows:

[0200] ;

[0201] in, Here, i represents the feedforward thrust value, and i is the load cell index. This is an estimated value for the coefficient of friction. To integrate reaction force values, For the center of gravity shift compensation item, For safety bias;

[0202] The formula for calculating the center of gravity shift compensation term is as follows:

[0203] ;

[0204] in, For the center of gravity shift compensation item, To compensate for the gain, To incorporate the sensitivity of reaction force to the position of the center of gravity, This represents the change in the position of the center of gravity. This is the arithmetic mean of the estimated friction coefficients.

[0205] In one embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program, the processor executing the computer program to implement the steps of the method for real-time correction of cumulative sliding construction positioning deviation of a large-span steel structure roof as described above.

[0206] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps in the above method embodiments.

[0207] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The device embodiments described above are merely illustrative. The components described as separate parts may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this disclosure according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0208] The above-described embodiments are merely illustrative of several implementation methods of the embodiments of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the embodiments of this application, and these modifications and improvements all fall within the protection scope of the embodiments of this application.

Claims

1. A method for real-time correction of cumulative sliding construction positioning deviation of a large-span steel structure roof, characterized in that, The method includes: Obtain the mass and centroid coordinates of the assembled vehicle, and calculate the change in center of gravity and theoretical reaction force based on the mass and centroid coordinates. Measured data is read from each sensor, and a health diagnosis is performed on the weighing sensor based on the measured data to obtain sensor health indicators; wherein, the measured data includes measured thrust, measured displacement, and measured reaction force; Based on the sensor health indicator, the measured reaction force is corrected to obtain the soft measurement reaction force. Based on the sensor health indicator, the soft measurement reaction force and the theoretical reaction force are weighted and summed to obtain the fused reaction force. Based on the fusion reaction force and the measured thrust, the friction coefficient estimate is calculated, and based on the change in center of gravity position, the friction coefficient estimate, and the fusion reaction force, the feedforward thrust is calculated. Based on the feedforward thrust and the measured displacement, PID feedback correction is performed to obtain the feedback correction amount; wherein, the feedback correction amount is used to instruct the actuator to perform deviation correction action.

2. The method according to claim 1, characterized in that, The step of correcting the measured reaction force based on the sensor's health indicator to obtain the soft-measurement reaction force includes: Based on the measured displacement, the original velocity of the current cycle is calculated, and based on the acceleration of the previous cycle, the original velocity, and the control cycle duration, the smoothed acceleration of the current cycle is calculated. If the sensor health indicator is abnormal, the equivalent mass, damping coefficient, and track slope angle are obtained. Based on the smooth acceleration, the equivalent mass, the damping coefficient, and the track slope angle, the original soft-sensor reaction force estimate is calculated, and the original soft-sensor reaction force estimate is corrected for reasonableness to obtain the soft-sensor reaction force. If the sensor health indicator is normal, then the measured reaction force is set as the soft measurement reaction force; The formula for calculating the smooth acceleration is as follows: ； in, For a smooth acceleration with period t, These are the weighting coefficients. The initial acceleration with period t, The acceleration has a period of t-1.

3. The method according to claim 2, characterized in that, The step of making a reasonable correction to the original soft-sensor reaction force estimate to obtain the soft-sensor reaction force includes: Based on the original soft-sensor reaction force estimate, a negative value test is performed to obtain a negative soft-sensor reaction force estimate, and the negative soft-sensor reaction force estimate is clamped to zero to obtain a non-negative clamping reaction force value. Based on the preset rated bearing capacity, the upper limit of the non-negative clamping reaction force value is cut off to obtain the upper limit cut-off reaction force value. Based on the reasonable soft measurement reaction force value of the previous cycle, the relative change rate of the upper limit cutoff reaction force value relative to the rated bearing capacity is calculated, and based on the relative change rate, a mutation test is performed to obtain the mutation test result. If the mutation test result is true, then based on the rated bearing capacity and the reasonable soft measurement reaction force value of the previous cycle, the mutation replacement value is calculated and the mutation replacement value is set as the soft measurement reaction force; If the mutation test result is false, then the upper limit cutoff reaction force value is set as the soft measurement reaction force.

4. The method according to claim 2, characterized in that, The original soft-sensor reaction force estimate is calculated based on the smooth acceleration, the equivalent mass, the damping coefficient, and the track slope angle. include: The formula for calculating the original soft-sensor reaction force estimate is as follows: ; in, This is the original soft-sensor reaction force estimate. For effective thrust, For equivalent quality, The acceleration is along the slip direction. This is the equivalent viscous damping coefficient. For speed, It is the acceleration due to gravity. This is the slope projection factor. is the estimated friction coefficient for the previous cycle, and i is the index of the weighing sensor.

5. The method according to claim 1, characterized in that, The calculation of the friction coefficient estimate based on the fused reaction force and the measured thrust includes: The apparent friction coefficient is calculated based on the fusion reaction force and the measured thrust. Based on the friction coefficient estimate from the previous period and the apparent friction coefficient, residual calculation is performed to obtain the residual value. Based on the residual value and a preset residual threshold, abrupt change detection is performed to obtain a change flag. Based on the mutation flag, the forgetting factor and covariance matrix are obtained, and based on the residual value, the forgetting factor and the covariance matrix, a recursive least squares update is performed to obtain a temporary friction coefficient estimate. The temporary friction coefficient estimate is physically limited to obtain a physically limited friction coefficient, and the rate of change of the physically limited friction coefficient is limited to obtain the friction coefficient estimate for the current period.

6. The method according to claim 1, characterized in that, The feedforward thrust is calculated based on the change in center of gravity, the estimated friction coefficient, and the fused reaction force. include: The formula for calculating the feedforward thrust is as follows: ； in, Here, i represents the feedforward thrust value, and i is the load cell index. This is an estimated value for the coefficient of friction. To integrate reaction force values, For the center of gravity shift compensation item, For safety bias; The calculation formula for the center of gravity shift compensation term is as follows: ； in, For the center of gravity shift compensation item, To compensate for the gain, To incorporate the sensitivity of reaction force to the position of the center of gravity, This represents the change in the position of the center of gravity. This is the arithmetic mean of the estimated friction coefficients.

7. A real-time correction device for cumulative sliding construction positioning deviation of a large-span steel structure roof, characterized in that, The device includes: The theoretical module is used to obtain the mass and centroid coordinates of the assembled vehicle, and to calculate the change in center of gravity and theoretical reaction force based on the mass and centroid coordinates. The diagnostic module is used to read measured data from each sensor and perform health diagnosis on the weighing sensor based on the measured data to obtain sensor health indicators; wherein, the measured data includes measured thrust, measured displacement and measured reaction force; The fusion module is used to correct the measured reaction force based on the sensor health indicator to obtain the soft measurement reaction force, and to perform a weighted summation of the soft measurement reaction force and the theoretical reaction force based on the sensor health indicator to obtain the fused reaction force. The thrust module is used to calculate the friction coefficient estimate based on the fused reaction force and the measured thrust, and to calculate the feedforward thrust based on the change in center of gravity position, the friction coefficient estimate and the fused reaction force. The correction module is used to perform PID feedback correction based on the feedforward thrust and the measured displacement to obtain a feedback correction amount; wherein the feedback correction amount is used to instruct the actuator to perform a deviation correction action.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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