Asphalt pavement paving and compaction cooperative control method

Abstract

This invention discloses a method for coordinated control of asphalt pavement paving and compaction, relating to the field of asphalt pavement construction technology. Before operation, the invention inputs basic data to the central control unit and calibrates the lower limit of the allowable temperature for compaction. During paving, it collects the three-dimensional position coordinates of the paver, the temperature data of the loose layer, and the thickness data of the loose layer. During compaction, it collects the three-dimensional position coordinates and trajectory of the roller, the temperature data of the compacted layer, and the compaction degree value. The central control unit synchronizes and matches the data, calculates the temperature drop rate, and issues elevation adjustment and additional compaction commands after comparing deviations. This invention enables precise coordination between paving and compaction processes, real-time calculation of the temperature drop rate and remaining compaction time, automatic elevation adjustment, and issuance of additional compaction commands, improving the construction quality and stability of ultra-thin wearing course layers, reducing early-stage defects, and extending the service life of the pavement.

Description

Technical Field

[0001] This invention relates to the field of asphalt pavement construction technology. More specifically, this invention relates to a method for coordinated control of asphalt pavement paving and compaction. Background Technology

[0002] Asphalt pavement paving and compaction are key procedures in road construction, directly affecting the pavement's smoothness, compaction degree, and service life. With the promotion of preventive maintenance technologies, ultra-thin wearing courses, only 3-10 mm thick, have been widely used in highway maintenance due to their advantages such as material saving, rapid construction, and effective restoration of pavement surface function. However, the paving thickness of ultra-thin wearing courses is extremely thin, and the asphalt mixture cools down very quickly after paving. The effective compaction temperature window is usually only tens of seconds to several minutes, requiring high control over construction temperature and compaction timing. If effective compaction is not completed before the asphalt mixture temperature drops to the lower limit of the allowable range, insufficient compaction will result, making it prone to early defects such as loosening and spalling later on.

[0003] In traditional construction methods, pavers and rollers operate independently, lacking unified collaborative control. This makes it difficult to achieve precise temporal and spatial matching between paving and compaction processes. Parameters such as paving thickness and loose-lay temperature cannot be effectively transmitted to the compaction stage to guide compaction operations. On-site construction quality control mainly relies on the experience and judgment of operators. Operators visually inspect the road surface temperature or use handheld thermometers to determine the timing and number of compactions based on their experience. This manual control method has significant shortcomings: First, temperature detection is mostly point-based, making it difficult to reflect the temperature distribution across the entire work section, resulting in insufficient data representativeness. Second, compaction decisions lag behind temperature changes; often, by the time the temperature has dropped to the lower limit, the optimal compaction window has been missed, easily leading to delayed compaction, insufficient compaction, or over-compaction. Third, paving elevation control relies on manual adjustment, resulting in a delayed response and difficulty in ensuring the uniformity of the ultra-thin wearing course thickness and compaction stability, thus affecting road performance and service life.

[0004] Therefore, how to achieve precise coordination between paving and compaction, accurate control of compaction timing, and timely adjustment of paving elevation during the construction of ultra-thin wear-resistant layers are technical problems that urgently need to be solved by those skilled in the art. Summary of the Invention

[0005] This invention provides a method for coordinated control of asphalt pavement paving and compaction, which can achieve precise coordination between paving and compaction processes, calculate the temperature drop rate and remaining compaction time in real time, automatically adjust the elevation, issue additional compaction commands, improve the construction quality and stability of ultra-thin wearing course, reduce early-stage defects, and extend the service life of the pavement.

[0006] To achieve these objectives and other advantages according to the present invention, a method for coordinated control of asphalt pavement paving and compaction processes is provided for paving ultra-thin wearing courses with a thickness of 3-10 mm, comprising the following steps: Before the paver starts working, the chainage range of the road section to be paved, the design elevation of each chainage, and the design compaction degree are input to the central control unit. The lower limit of the allowable temperature for compaction is calibrated through field tests. The range of the lower limit of the allowable temperature for compaction is 100-110℃. The central control unit is used to receive monitoring data in real time, perform calculations and processing, and send control commands to the paver and roller. During the paving operation, the first positioning receiver installed on the paver acquires the paver's three-dimensional position coordinates in real time at a frequency of not less than 20Hz, and the first infrared temperature sensor installed on the paver acquires the surface temperature field data of the entire cross-section of the paved layer in real time as the loose layer temperature data T. s An ultrasonic thickness gauge installed on the paver acquires the thickness data of the loose paving layer in real time. During the compaction operation of the road roller, a second positioning receiver installed on the road roller acquires the three-dimensional position coordinates and running trajectory of the road roller in real time at a frequency of not less than 20Hz. A second infrared temperature sensor installed on the road roller acquires the surface temperature of the compacted road surface in real time as the temperature data T of the compacted layer. r The compaction gauge installed on the road roller obtains the compaction value of the road surface being rolled in real time; The central control unit receives and stores the paver's three-dimensional position coordinates and loose layer temperature data in real time. s Data on the thickness of the loose paving layer, the three-dimensional position coordinates and running trajectory of the roller, and the temperature data of the compacted layer (T). r The compaction value of the rolled pavement was also measured, and the first and second positioning receivers were synchronized in time. The temperature data T of the loose layer within the same station range with a time difference of less than 30 seconds was also collected. s With the temperature data of the compacted layer T r Grouped into one group, the actual temperature drop rate V = (T) of the asphalt mixture within that chainage range from the paving time to the compaction time is calculated based on the temperature data of that group. s -T r ) / Δt, where V is the actual temperature drop rate, and T s For loose layer temperature data, T r The data represents the temperature of the compacted layer, where Δt is the time difference between the acquisition of the temperature data of the loose layer and the temperature data of the compacted layer. The central control unit compares the received three-dimensional position coordinates of the paver with the chainage range and design elevation of the road section to be paved. When the deviation between the three-dimensional position coordinates of the paver and the design elevation exceeds ±5mm, it sends an elevation adjustment command to the paver control system. The central control unit compares the received compaction value of the rolled pavement with the design compaction value. When the compaction value of the rolled pavement is lower than the design compaction value, it looks up the corresponding loose layer temperature data T based on the station range of the substandard area. s Given the actual temperature drop rate V, predict the remaining time t that the substandard area can be compacted after the current moment. r = (T r -T min ) / V, where t r To be able to crush the remaining time, T r For the current compaction layer temperature data, T min This is the lower limit of the allowable temperature for compaction. If the remaining compaction time t is... r If the value is greater than zero, an additional compaction command is sent to the roller control system. The additional compaction command includes the number of additional compaction passes calculated based on the difference between the current compaction value and the design compaction value, with one additional compaction pass for every 1% difference below the design compaction value.

[0007] Preferably, the central control unit acquires the ambient temperature T at the construction site in real time. a Given the ambient wind speed W, a temperature difference-driven model based on Newton's law of cooling is used to compensate for the actual temperature drop rate V. The central control unit then uses the compensated temperature drop rate V. c Replace the actual temperature drop rate V with the prediction of the remaining time for compaction. V c = V·[1+k1·(T s -T a ) / (T s -T a )0+k2·(W / W0)], Among them (T) s -T a W0 is the reference temperature difference calibrated through field tests, ranging from 30-50℃; W0 is the reference wind speed, with a value of 2 m / s; k1 and k2 are dimensionless correction coefficients obtained through regression analysis, with k1 ranging from 0.1-0.3 and k2 ranging from 0.05-0.15; T a The unit is ℃, and W is in m / s.

[0008] Preferably, the central control unit has a built-in Kalman filter that processes the compacted layer temperature data sequence T obtained from multiple consecutive compaction times within the same pile number range. r(k) and the compensated temperature drop rate sequence V calculated at the corresponding time. c(k) As the observation input, a state transition matrix considering the thermal inertia of the asphalt mixture is established. The temperature drop rate is then smoothly estimated using a Kalman filter recursive algorithm to obtain the noise-reduced temperature drop rate V. kfThe central control unit adopts V kf Temperature drop rate V after replacement compensation c To predict the remaining time that can be crushed, The state equation and observation equation of the Kalman filter are as follows: V k = A·V k-1 +B·u k-1 +w k-1 , V c(k) = V k +v k , Where A is the state transition matrix, B is the control matrix, u is the rate of change of ambient temperature, and w and v are the process noise and observation noise, respectively.

[0009] Preferably, the lower limit of the allowable temperature for compaction, T, is... min Based on the penetration grade P of the asphalt mixture, the paving thickness h, and the ambient temperature T a Dynamic adjustment; the central control unit adopts a dynamically adjusted T min 'Predict the remaining time that it can be crushed,' T min ' = T base +α·(P0-P)+β·(h0-h)+γ·(T a0 -T a ), Where T base The lower limit of the reference temperature is determined through field testing and the value range is 100-110℃. P is the asphalt penetration, in units of 0.1 mm, P0 is the reference penetration, with a value of 80, h is the paving thickness, in units of mm, h0 is the reference thickness, with a value of 5 mm, and T... a The ambient temperature is expressed in °C (°C) or T. a0 The reference ambient temperature is 20℃. α, β, and γ are material property coefficients. The value of α ranges from 0.1 to 0.3℃ per unit penetration, the value of β ranges from 1.5 to 2.5℃ / mm, and the value of γ ranges from 0.3 to 0.7℃ / ℃.

[0010] Preferably, the calculation of the additional compaction passes N adopts a logarithmic model based on the compaction degree growth curve: N = ceil[a·ln((D des -D0) / (D des -D act ))], Among them, D des To design the compaction degree, D actD0 is the current compaction degree value, D0 is the initial compaction degree benchmark value obtained through field test sections, a is the compaction efficiency coefficient with a value range of 1.2-2.0, ln is the natural logarithm, and ceil is the round-up value, and is calculated based on the remaining compaction time t. r Less than the preset safety time threshold T safe When N is incremented by 1, T is incremented by 1. safe The value range is 8-12s.

[0011] Preferably, the loose layer temperature data T within the same station number range with a time difference of less than 30 seconds are used. s With the temperature data of the compacted layer T r When grouped together, if multiple loose layer temperature data or multiple compacted layer temperature data exist within the same chainage range, the equivalent loose layer temperature T at the center point P0 of that chainage is calculated using the distance-weighted inverse proportional interpolation method. seq and equivalent compacted layer temperature T req , T seq = Σ(w i ·T s,i ) / Σw i , T req = Σ(w i ·T r,i ) / Σw i , Where the weight w i =1 / d i 2 d i Let T be the planar distance from the i-th measuring point to the center point P0 of the station number. s,i T represents the temperature data of the i-th loose layer temperature measurement point. r,i For the temperature data of the i-th compaction layer temperature measuring point, the central control unit uses T... seq and T req The representative temperature data for this group was used to calculate the rate of temperature drop.

[0012] Preferably, both the first and second positioning receivers are equipped with a signal loss emergency module. When the positioning receiver cannot obtain a valid satellite signal, the signal loss emergency module automatically switches to the inertial navigation unit to calculate the position. Position estimation is based on dead reckoning, using the last valid satellite positioning data frame before signal loss as the initial reference point (X0, Y0, Z0) and initial attitude angle. The inertial navigation unit collects three-axis acceleration (α) in real time. x , a y , a z ) and triaxial angular velocity (ω x , ω y , ωz The velocity increment and attitude change in the carrier coordinate system are obtained through integration, and then transformed to the construction plane coordinate system through a coordinate transformation matrix. The position coordinates (X, Y, X) at the current moment are calculated by accumulating these coordinates. t , Y t Z t ); V t = V t-1 +∫a·dt, P t = P t-1 +∫V t ·dt, Among them, V t Let P be the velocity vector at the current moment. t Given the current position vector, the inertial navigation unit outputs the calculated position coordinates at a frequency of not less than 10Hz until the satellite signal is restored. At the same time, the central control unit records the deviation between the calculated trajectory and the measured trajectory after the signal is restored, and uses it for subsequent inertial navigation zero-bias correction.

[0013] Preferably, when the central control unit sends an elevation adjustment command to the paver control system, it also considers the current paver travel speed v. p The adjustment rate v of the ironing plate is dynamically adjusted based on the elevation deviation value ΔH. adj , v adj = v b ×(ΔH / ΔH ref )×(v ref / v p ), Among them, v b The baseline adjustment rate is 0.5-1.0 mm / s, and ΔH is the absolute value of the current elevation deviation in mm. ref The reference deviation value is 5mm, v ref The baseline paving speed is set at 3 m / min. When ΔH < 8 mm, proportional control is used, and when ΔH ≥ 8 mm, proportional-integral control is used, and a deceleration warning is sent to the paver control system at the same time.

[0014] Preferably, a buffer mounting bracket is provided between the ultrasonic thickness gauge and the screed. The buffer mounting bracket includes a fixed base, a guide column, and a shock-absorbing spring. The ultrasonic thickness gauge is floatingly connected to the guide column through the shock-absorbing spring, so that the probe end of the ultrasonic thickness gauge always maintains contact with the surface of the loosely laid layer during the paving process and the pressure is constant.

[0015] Preferably, the central control unit is equipped with a fault classification response module, which pre-stores multiple fault levels, defined in descending order as follows: Level 1 faults are core control failures, including communication interruptions between the central control unit and the paver control system or roller control system for more than 5 seconds, or failures of the central control unit's main processor. When a Level 1 fault occurs in the central control unit, it immediately saves the last complete set of data before the interruption to the local data buffer, sends the highest priority audible and visual alarm to the field operation terminal, and temporarily switches the permission to issue additional compaction commands to manual confirmation mode, allowing the field operator to judge whether to add compaction based on experience. Level 2 faults are positioning data failures, including the loss of satellite signal lock of the first or second positioning receiver and the inertial navigation unit calculation time exceeding 30 seconds, or positioning data jumps exceeding a preset threshold. When a level-two fault occurs in the central control unit, the calculation of the temperature drop rate and the automatic elevation adjustment are suspended. The last valid elevation command before the lockout is lost is maintained, and a positioning fault alarm is sent to the field operation terminal, prompting the operator to reduce speed or stop the operation until the signal is restored. Level 3 faults are caused by abnormal sensor data, including: Both the first infrared temperature sensor and the second infrared temperature sensor are equipped with redundant temperature sensors. When the difference between the data collected by the primary sensor and the redundant sensor exceeds 5°C. The difference between the data collected by the electromagnetic induction compaction meter and the radar compaction meter exceeds 3% of the design compaction degree; The ultrasonic thickness gauge data exceeded the preset threshold range for 3 consecutive seconds. When a Level 3 fault occurs in the central control unit, it automatically switches to redundant sensor data or a verification data source, suspends the issuance of control commands affected by the sensor, and sends a specific sensor fault alarm to the field operation terminal, prompting the sensor to be replaced or cleaned. Level 4 faults are caused by unstable data links, including communication interruptions between the central control unit and the external network, or abnormal write speeds of the local data buffer. When a Level 4 fault occurs in the central control unit, all monitoring data is automatically stored in the local data buffer and automatically retransmitted to the data processing module of the central control unit after communication is restored. At the same time, the collection frequency of non-core data is reduced to alleviate the system load. When two or more faults occur simultaneously, the fault classification response module executes the corresponding handling strategies sequentially according to the fault level from high to low, and only executes the handling strategy corresponding to the highest level fault until that level fault is resolved before handling the next highest level fault. After the fault is resolved, the system automatically returns to normal operating mode. This invention includes at least the following beneficial effects: First, this invention transforms pavers and rollers from traditional independent operation modes to unified collaborative operation modes. It achieves precise connection between paving and compaction processes through dual matching of time and space. Real-time calculation of temperature drop rate and remaining compaction time provides quantitative basis for compaction operations. Automatic elevation adjustment improves the uniformity of paving thickness and the accuracy of elevation control. Additional compaction is timely to supplement compaction, improve the construction quality stability of ultra-thin wearing course, reduce the probability of early defects, and extend the service life of the road surface.

[0016] Secondly, this invention effectively eliminates the deviation of ambient temperature and wind speed in the calculation of temperature drop rate. It obtains the accurate compensated temperature drop rate through a compensation model driven by Newton's law of cooling, and then smooths and reduces noise through Kalman filtering to filter out high-frequency noise caused by on-site interference, retain the true trend of temperature drop, improve the accuracy of predicting the remaining time for compaction, avoid system malfunctions, and enhance the operational stability and environmental adaptability of the collaborative control system.

[0017] Third, this invention enables the lower limit of the allowable temperature for compaction to dynamically adapt to the asphalt penetration, paving thickness, and ambient temperature, avoiding the adaptability defects of fixed temperature values. The additional compaction passes adopt a logarithmic model that conforms to the nonlinear law of asphalt compaction. When the remaining compaction time is less than the preset safe time threshold, one additional compaction pass is automatically added to avoid insufficient or excessive compaction and ensure stable and reliable compaction quality under different working conditions.

[0018] Fourth, this invention integrates multi-point temperature data through distance-weighted inverse interpolation to obtain the equivalent temperature of the station area, reducing the impact of single-point abnormal temperatures, improving the accuracy of temperature drop rate calculation, and automatically switching to inertial navigation emergency positioning when satellite signal is lost. With zero bias correction, it achieves continuous positioning under complex working conditions, avoids interruption of collaborative control, and meets the continuous construction requirements of ultra-thin wear-resistant layers.

[0019] Fifth, this invention dynamically adjusts the screed elevation adjustment rate to adapt to paving speed and elevation deviation, and, in conjunction with proportional / proportional integral control, avoids overshoot or lag in adjustment, improves the uniformity of paving thickness, uses a buffer support to isolate paver vibration, ensures stable ultrasonic thickness gauge data, and provides fault-level response to address various anomalies in a targeted manner to prevent fault escalation and improve system robustness and construction safety.

[0020] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Detailed Implementation

[0021] The present invention will now be described in further detail to enable those skilled in the art to implement it based on the description.

[0022] It should be understood that terms such as "having," "comprising," and "including" as used herein do not exclude the presence or addition of one or more other elements or combinations thereof. It should be noted that the experimental methods described in the following embodiments, unless otherwise specified, are conventional methods and therefore should not be construed as limiting the invention.

[0023] This invention provides a method for coordinated control of asphalt pavement paving and compaction processes, used for paving ultra-thin wearing courses with a thickness of 3-10mm. The ultra-thin wearing course is the structural layer of the asphalt pavement after paving. Its characteristics include an extremely thin structural layer, resulting in a relatively large contact area between the asphalt mixture and air after paving, leading to very rapid heat dissipation. The effective compaction window is often only tens of seconds to several minutes. This invention aims to solve the problem of precise coordination between the paving and compaction processes. The invention includes the following steps: Before the paver starts working, the station range of the road section to be paved, the design elevation of each station, and the design compaction degree are input into the central control unit. After the basic data is input, the operator calibrates the minimum allowable temperature for compaction under the current asphalt mixture grade and current construction environment conditions through field tests. The minimum allowable temperature for compaction is the lowest temperature at which the asphalt mixture can achieve effective compaction. If compaction continues below this temperature, it will easily lead to loose structure or difficulty in compaction. By setting multiple temperature measuring points in the test section and simultaneously conducting compaction degree tests, the minimum temperature boundary that can guarantee the compaction quality is determined. The range of the minimum allowable temperature for compaction is 100-110℃. The central control unit is used to receive monitoring data in real time, perform calculations and processing, and send control commands to the paver and roller. During the paving operation, the first positioning receiver installed on the paver acquires the paver's three-dimensional position coordinates in real time at a frequency of no less than 20Hz, reflecting the paver's real-time position in the construction plane coordinate system. The first infrared temperature sensor installed on the paver acquires the surface temperature field data of the entire cross-section of the paved layer in real time as the loose layer temperature data T. s The ultrasonic thickness gauge, which is set on the screed of the paver, reflects the initial thermal state of the asphalt mixture that has just been laid. It obtains the thickness data of the loose layer in real time. During the compaction operation of the road roller, a second positioning receiver mounted on the road roller acquires the three-dimensional position coordinates and running trajectory of the road roller in real time at a frequency of not less than 20Hz, reflecting the real-time position and running trajectory of the road roller in the construction plane coordinate system. A second infrared temperature sensor mounted on the road roller acquires the surface temperature of the compacted road surface in real time as the temperature data T of the compacted layer. r The compaction gauge, installed on the roller, reflects the real-time thermal state of the mixture. It obtains the compaction value of the road surface being rolled in real time, reflecting the degree of compaction achieved by the road surface after a certain number of rolling passes. The central control unit receives and stores the paver's three-dimensional position coordinates and loose layer temperature data in real time. s Data on the thickness of the loose paving layer, the three-dimensional position coordinates and running trajectory of the roller, and the temperature data of the compacted layer (T). r The compaction value of the rolled pavement was also measured, and the first and second positioning receivers were synchronized to ensure that the two positioning systems used a unified time reference for data acquisition. This ensured that data collected by different devices at the same time could be matched in time, and that the temperature data T of the loose layer within the same station range with a time difference of less than 30 seconds was also collected. s With the temperature data of the compacted layer T r Grouped together, the temperature change of the ultra-thin wearing course within 30 seconds is within a predictable range. If the time difference is too large, there is no direct correlation between the paving and compaction states, making it unusable for effective calculation. For each successfully matched set of temperature data, the actual temperature drop rate V = (T) of the asphalt mixture within that station range from the paving time to the compaction time is calculated based on that set of temperature data. s -T r ) / Δt, reflects the rate of cooling of the material under natural conditions, where V is the actual temperature drop rate and T is the Δt value. s For loose layer temperature data, T r The data represents the temperature of the compacted layer, where Δt is the time difference between the acquisition of the temperature data of the loose layer and the temperature data of the compacted layer. The central control unit compares the received three-dimensional position coordinates of the paver with the chainage range and design elevation of the road section to be paved. When the deviation between the three-dimensional position coordinates of the paver and the design elevation exceeds ±5mm (based on the construction accuracy requirements of the ultra-thin wear layer and the mechanical execution capability, it can ensure the accuracy of thickness control and avoid frequent system actions due to small fluctuations), it sends an elevation adjustment command to the paver control system, driving the screed to adjust its height according to the direction of deviation, so as to restore the paving thickness to the design requirement range. The central control unit compares the received compaction value of the rolled pavement with the design compaction value. When the compaction value of the rolled pavement is lower than the design compaction value, it retrieves the corresponding loose layer temperature data T from the stored historical data based on the station range of the substandard area. s Given the actual temperature drop rate V, predict the remaining time t that the substandard area can be compacted after the current moment. r = (T r -T min The formula t / V gives the remaining time from the current moment when the region can maintain an effective compaction state, where t is the mean of the time. r To be able to crush the remaining time, T r For the current compaction layer temperature data, T minThis is the lower limit of the allowable temperature for compaction. If the remaining compaction time t is... r A value greater than zero indicates that there is still a sufficient time window for supplementary compaction before the asphalt mixture temperature drops to the lower limit of the allowable temperature. In this case, an additional compaction command is sent to the roller control system. The additional compaction command includes the number of additional compaction passes calculated based on the difference between the current compaction value and the design compaction value, with one additional compaction pass for every 1% difference from the design compaction value. For example, if the current compaction value is 2% lower than the design value, then two additional compaction passes are required.

[0024] In the above technical solution, pavers and rollers are transformed from traditional independent operation modes to unified collaborative operation modes. Through dual matching of time and space, the paving and compaction processes are precisely connected. Real-time calculation of temperature drop rate and remaining compaction time provides a quantitative basis for compaction operations, avoiding problems such as insufficient compaction and excessively low temperature caused by lag or deviation in human judgment. Automatic elevation adjustment can improve the uniformity of paving thickness and the accuracy of elevation control, reducing the delay and error caused by manual adjustment. Additional compaction can be carried out in a timely manner when the compaction degree is insufficient, improving the overall density and uniformity of the road surface, making the construction quality of the ultra-thin wearing course more stable and reliable, reducing the probability of early road surface defects, and extending the service life of the road surface.

[0025] In actual construction, ambient temperature and wind speed significantly alter the heat dissipation rate of asphalt mixtures. Calculating the temperature drop rate solely based on the temperature difference between paving and compaction, without considering the influence of the external environment, can easily lead to calculation errors. This, in turn, results in inaccurate predictions of the remaining compaction time, affecting the judgment of compaction timing and the effectiveness of compaction control. In another technical solution, the central control unit acquires the ambient temperature T at the construction site in real time. a And ambient wind speed W, ambient temperature T a The ambient wind speed (W) directly affects the heat loss rate of asphalt mixtures. Increased ambient wind speed accelerates heat exchange on the material surface, significantly increasing the temperature drop rate. The cooling rate of an object is related to the temperature difference between its surface and the surrounding environment; the greater the temperature difference, the faster the cooling rate. Based on the temperature difference between the material and the environment, as well as the influence of wind speed, the temperature drop rate is corrected. A temperature difference-driven model based on Newton's law of cooling is used to compensate for the actual temperature drop rate (V). The central control unit uses the compensated temperature drop rate (V). c The actual temperature drop rate V is replaced to predict the remaining time for compaction. Through compensation, V c It can more accurately reflect the actual heat dissipation rate of asphalt mixtures under current environmental conditions: V c = V·[1+k1·(T s -T a ) / (T s -T a)0+k2·(W / W0)], Among them (T) s -T a W0 represents the reference temperature difference calibrated through field tests, ranging from 30-50℃. W0 is the reference wind speed, a standard wind speed reference value used for comparison calculations, with a value of 2 m / s. k1 and k2 are dimensionless correction coefficients obtained through regression analysis. Temperature difference is the dominant factor in heat dissipation, while wind speed is a secondary factor. k1 reflects the intensity of the influence of temperature difference changes on the temperature drop rate of the ultrathin wear layer; a smaller value indicates a relatively mild influence of temperature difference, consistent with the characteristics of ultrathin layers being thin and having small heat capacity. The value range of k1 is 0.1-0.3. k2 reflects the intensity of the influence of wind speed changes on the temperature drop rate of the ultrathin wear layer, with a value range of 0.05-0.15. T a The unit is ℃, and W is in m / s; When the actual temperature difference (T) s -T a ) greater than the reference temperature difference (T) s -T a When the temperature drops to 0, it indicates that the ambient temperature is relatively low or the mixture temperature is relatively high, the heat dissipation driving force is enhanced, and the temperature drop rate should be appropriately increased. At this time, k1·(T) s -T a ) / (T s -T a The term 0 is positive, making V c The value is greater than V; conversely, when the actual temperature difference is less than the reference temperature difference, this term is negative. c When the actual wind speed W is greater than the reference wind speed W0, convective heat transfer is enhanced, and the temperature drop rate should also increase. In this case, the k2·(W / W0) term is positive, and vice versa. For example, in cold and windy weather, the uncompensated temperature drop rate V may be too small, leading to an underestimation of the remaining time t. r The time frame is too long; the system might mistakenly interpret this as sufficient time remaining and delay the overtaking maneuver. After compensation, V... c Increase the predicted remaining time t r The corresponding reduction allows for timely issuance of compaction commands, ensuring that the operation is completed within the temperature window.

[0026] The above technical solution can effectively eliminate the deviation caused by changes in ambient temperature and wind speed in the calculation of temperature drop rate, so that the system can maintain stable judgment accuracy under different weather, time periods and wind conditions. The correction process of temperature drop rate makes the prediction of the remaining time that can be rolled more closely match the actual cooling process, avoids the error in judging the timing of rolling due to sudden environmental changes, and improves the environmental adaptability of the construction process of ultra-thin wear layer.

[0027] Temperature data at construction sites is easily affected by external interference and fluctuates. Directly using the compensated temperature drop rate for calculation results in insufficient data stability, significant noise, and impacts the accuracy of rolling time prediction. In another technical solution, the central control unit incorporates a Kalman filter to smooth the temperature drop rate data. After environmental compensation for the temperature drop rate, the system uses a sequence of compacted layer temperature data T obtained from multiple consecutive compaction times within the same pile number range. r(k) and the compensated temperature drop rate sequence V calculated at the corresponding time. c(k) As an observation input, the characteristic of asphalt mixture maintaining its original temperature state during temperature changes causes the temperature drop process to exhibit a certain lag and stability. The filtering module constructs a state transition relationship based on the thermal inertia of the asphalt mixture, establishing a state transition matrix that considers the thermal inertia. The temperature drop rate is then smoothly estimated using a Kalman filter recursive algorithm to obtain the noise-reduced temperature drop rate V. kf The central control unit adopts V kf Temperature drop rate V after replacement compensation c To predict the remaining time that can be crushed, The state equation and observation equation of the Kalman filter are as follows: V k = A·V k-1 +B·u k-1 +w k-1 ; V c(k) = V k +v k ; The first relationship is the state equation, which reflects the correlation between the current rate of temperature drop and the previous rate of temperature drop. It also considers the influence of the ambient temperature change rate, as well as the uncertainties caused by system variations and external disturbances. This uncertainty is manifested through process noise, reflecting the thermal inertia characteristics of asphalt mixtures, i.e., temperature changes exhibit a certain lag and stability. The state equation is a time-updated equation, based on the previous rate of temperature drop V. k-1 Combined with the rate of change of ambient temperature u k-1 The control effect predicts the current temperature drop rate V. k w k-1 This is process noise, characterizing the uncertainties within the system (such as minute changes in the thermophysical properties of asphalt mixtures). The second relationship is the observation equation, which correlates the actual collected compensated temperature drop rate with the filtered true temperature drop rate. The observation noise mainly comes from various interferences at the construction site, such as equipment vibration and changes in ambient light, causing fluctuations in the temperature data. The observation equation is a measurement update equation, establishing the true temperature drop rate V. k The compensated temperature drop rate V calculated by the sensorc(k) The linear relationship, v k To observe noise and characterize the data acquisition interference at the construction site (such as the error caused by sunlight and vibration affecting the infrared sensor); Where A is the state transition matrix, which describes the law of change of system state over time and reflects the dynamic change characteristics of temperature drop rate; B is the control matrix, which describes the degree of influence of external input on system state. The state transition matrix A and the control matrix B are preset according to system characteristics; u is the rate of change of ambient temperature; w and v are the process noise and observation noise, respectively, representing the uncertainty of the system's own changes and the interference introduced during sensor acquisition; and k represents the sampling time sequence number. The central control unit has a built-in Kalman filter module, which is pre-calibrated based on asphalt mixture thermal inertia tests to determine the state transition matrix A, control matrix B, and w. k-1 v k The covariance matrix; For the same station range, multiple sets of T data were continuously collected. r(k) and Vitamin C (k) As an observation input; First, predict V using the state equation. k Then, by combining the observation equation with V c(k) Calculate the Kalman gain, correct the predicted value, and obtain a smoothed V. kf ; With V kf Replace V c Participate in the calculation of remaining time that can be crushed.

[0028] The Kalman filter module performs optimal estimation in a recursive manner using two steps: prediction and update. In the prediction step, the system uses the optimal estimate V from the previous time step. k-1 Based on the state equation, the system predicts the prior state estimate and its error covariance at the current moment. In the update step, the system combines the observation value V at the current moment. c(k) Based on the prediction results, the Kalman gain is calculated, and then the optimal posterior estimate V of the state at the current time is obtained. kf By using this recursive method, the estimation results from the previous moment are fused with the observation data from the current moment. This process suppresses noise interference while preserving the true trend of change, ultimately outputting the temperature drop rate V after noise reduction and smoothing. kf The filtered temperature drop rate V kf It preserves the true physical laws of change while effectively filtering out high-frequency noise, allowing for the remaining time t of compaction. rThe prediction accuracy is greatly improved, the control command output is more stable and reasonable, and the additional compaction command received by the road roller operator no longer changes frequently. For example, when the sensor is subjected to instantaneous electromagnetic interference or local segregation of the mixture causes abnormal single measurement values, the Kalman filter can use historical data trends to suppress abnormal values ​​and avoid frequent system malfunctions caused by data fluctuations.

[0029] The above technical solution can significantly reduce the impact of various interference factors on temperature and rate data at the construction site, making the trend of temperature drop rate clearer and more stable. The Kalman filter algorithm effectively suppresses high-frequency noise without changing the real physical change law, avoiding frequent system malfunctions caused by data fluctuations. The smoothed temperature drop rate can improve the prediction accuracy of the remaining time that can be rolled, making the control command output more stable and reasonable, and improving the operation stability and control reliability of the entire collaborative control system. It is especially suitable for road construction sites with complex working conditions and many interferences.

[0030] In traditional construction, the lower limit of the allowable lower temperature for compaction is often a fixed value, failing to consider the differences in asphalt material properties, paving thickness, and ambient temperature. For ultra-thin wearing courses with varying penetration and thickness, a uniform lower limit can easily lead to excessively high or low compaction temperatures, making it difficult to achieve precise compaction control that matches the working conditions. In another technical solution, the central control unit no longer uses a fixed lower limit value T for the allowable lower temperature for compaction. min The minimum allowable temperature for compaction, T min Based on the penetration grade P of the asphalt mixture (mixture proportion design report), the paving thickness h, and the ambient temperature T a Dynamic adjustment; the central control unit adopts a dynamically adjusted T min 'Predict the remaining compaction time so that the lower limit of the temperature can be adapted in real time according to the characteristics of the asphalt mixture, the paving thickness, and the ambient temperature, and the minimum compaction temperature changes in real time with the working conditions:' T min ' = T base +α·(P0-P)+β·(h0-h)+γ·(T a0 -T a ), Where T baseis the lower limit value of the reference temperature, which is the lowest temperature boundary for effective compaction under the current asphalt mixture grade and construction base environment. When the temperature is lower than this reference value, even without the influence of other factors, the viscosity of the asphalt mixture will be too high, and effective interlock and cohesion between particles cannot be achieved, resulting in diseases such as loose structure and insufficient compaction degree after rolling. It is calibrated through on-site tests and the value range is 100 - 110 °C. P is the penetration of asphalt, an index reflecting the hardness and softness of asphalt materials. The higher the value, the softer the asphalt, with relatively poor high-temperature stability but better low-temperature crack resistance, and the unit is 0.1 mm. P0 is the reference penetration, with a value of 80. h is the paving thickness, and the ultra-thin wearing course h is between 3 - 10 mm, with the unit of mm. h0 is the reference thickness, with a value of 5 mm, T a is the ambient temperature, with the unit of °C, T a0 is the reference ambient temperature, with a value of 20 °C. α, β, and γ are material characteristic coefficients. α reflects the influence of asphalt penetration on the lower temperature limit, that is, the adjustment range of the lower limit of the rolling temperature for each 1-unit change in penetration. The value range of α is 0.1 - 0.3 °C per unit of penetration. β reflects the influence of paving thickness on the lower temperature limit. The paving thickness is the dominant influencing factor for the lower limit of the rolling temperature of the ultra-thin wearing course. The value range of β is 1.5 - 2.5 °C / mm. γ reflects the influence of ambient temperature on the lower temperature limit, that is, the adjustment range of the lower limit of the rolling temperature for each 1 °C change. The value range of γ is 0.3 - 0.7 °C / °C; When P > P0 (soft asphalt): P0 - P < 0, the correction term is negative, T min ’decreases, giving full play to the low-temperature compaction performance of soft asphalt and avoiding too high lower temperature limit resulting in too long rolling time and mixture pushing; When P < P0 (hard asphalt): P0 - P > 0, the correction term is positive, T min ’increases, ensuring that the hard asphalt is compacted at a sufficient temperature and avoiding the loose structure caused by low-temperature rolling; When h < h0 (extremely thin layer, such as 3 - 4 mm): h0 - h > 0, the correction term is positive and the increase amplitude is the largest, T min ’significantly increases,争取更多有效时间for the rolling operation, adapting to the characteristics of extremely fast heat dissipation and extremely short window period of the extremely thin layer, and avoiding missing the best rolling opportunity due to too low lower temperature limit; When h > h0 (thicker layer): h0 - h < 0, the correction term is negative, T min ’decreases appropriately, making full use of the heat preservation characteristics of the thicker layer and avoiding excessive rolling caused by too high lower temperature limit, and improving the pavement flatness; When T a <T a0 (low-temperature construction, such as in winter, morning and evening): T a0 -T a > 0, the correction term is positive, T min'Raising the height allows for more effective time for compaction operations and is adapted to the rapid heat dissipation characteristics in low-temperature environments;' When T a >T a0 (High-temperature construction, such as midday in summer): T a0 -T a <0, the correction term is negative, T min 'Reduce the temperature to avoid excessively high lower limit of temperature, which would lead to excessively long compaction time and prevent the mixture from shifting, shoving, and other defects at high temperatures;' Before construction, the central control unit pre-stores the penetration P of the asphalt mixture and the designed paving thickness h. During construction, the T data is collected in real time. a ; Calculate the three correction terms sequentially, and then sum them up to T. base Get T min '; With T min 'Replace T' min , participate in t r = (T r -T min Calculation of ) / V; For different types of asphalt, soft asphalt with high penetration uses a lower T value. min To fully utilize its low-temperature compaction performance, hard asphalt with low penetration is compacted using a higher Ti. min Ensure compaction is completed at a sufficient temperature; for different paving thicknesses, use a higher T for extremely thin layers. min To achieve compaction within a limited time, a relatively low T can be used for thicker layers. min By fully utilizing the thermal insulation properties of the materials, and actively increasing the temperature during low-temperature construction, the thermal insulation capacity can be optimized for different ambient temperatures. min To allow more effective time for compaction operations, the temperature (T) should be appropriately reduced during high-temperature construction. min To avoid stopping compaction too early.

[0031] The above technical solution enables the minimum rolling temperature to be precisely matched with the actual construction conditions, avoiding the problem of poor adaptability caused by fixed temperature values. The corresponding minimum rolling temperature is adopted for different asphalt types, different paving thicknesses, and different ambient temperatures. This ensures the compaction effect while avoiding resource waste caused by excessively high temperatures or insufficient compaction caused by excessively low temperatures, so that the ultra-thin wearing course can maintain stable and reliable compaction quality under varying construction conditions.

[0032] If the original compaction degree difference and the number of compaction passes are treated as having a simple linear relationship, insufficient or excessive compaction is likely to occur. In another technical solution, asphalt mixtures exhibit a nonlinear characteristic of rapid early-stage growth and slow later-stage growth during compaction. The calculation of the additional compaction passes N uses a logarithmic model based on the compaction degree growth curve, which truly reflects the relationship between the number of compaction passes and the compaction degree. N = ceil[a·ln((D des -D0) / (D des -D act ))] Among them, D des To design the compaction degree, D act D0 is the current compaction degree value, D0 is the initial compaction degree benchmark value obtained through field test sections, and 'a' is the compaction efficiency coefficient, used to adjust the steepness of the curve. The larger 'a' is, the more calculation passes are required to achieve the same compaction degree, which is suitable for mixtures that are difficult to compact or equipment with weak compaction capacity. The smaller 'a' is, the fewer calculation passes are required, which is suitable for materials that are easy to compact. The value range is 1.2-2.0, ln is the natural logarithm, and ceil() is the round-up function. The remaining compaction time t is used when... r Less than the preset safety time threshold T safe When the effective compaction time is about to be exhausted, even if the calculation result according to the logarithmic model is sufficient, to ensure compaction reliability, N is automatically increased by 1 pass, adding one more compaction pass to improve compaction reliability. T safe The value range is 8-12s; When D act Approaching D0, that is, at the beginning of the compaction stage, (D des -D0) / (D des -D act When the value of D approaches 1, the logarithmic value naturally approaches 0, and the required number of passes N is very small, which conforms to the pattern that initial compaction is easy. As the number of compaction passes increases, D... act Gradually increase and approach D des denominator (D) des -D act As the number of compaction gradually decreases, the true value increases rapidly, and the logarithmic value increases accordingly, reflecting the pattern that more compaction passes are needed for every 1% increase in compaction in the later stages. Central control unit real-time comparison D act With D des When D act <D des At that time, retrieve D0 and a, substitute them into the logarithmic core to complete the calculation; The calculation result is rounded up to obtain the additional number of compaction passes N. Simultaneously determine the remaining time t for crushing. r With T safe The size of t, if tr <T safe If N is positive, then add 1 to N; The final N is written into the additional compaction command and sent to the roller control system.

[0033] In the above technical solution, the calculation of the number of compaction passes is more in line with the actual compaction law of asphalt mixtures, avoiding the problems of insufficient or excessive compaction caused by linear proportional calculation. The logarithmic model can reasonably increase the number of passes when approaching the design compaction degree, so that the compaction degree is uniformly improved and local under-compaction or over-compaction areas are avoided. It is suitable for the construction of ultra-thin abrasive layers with short effective compaction time and high control accuracy requirements, and significantly improves the stability and reliability of compaction quality.

[0034] Within the same station number range, there may be multiple temperature measuring points, which are scattered. Directly using a single temperature data point for calculation is insufficiently representative and can easily lead to errors in the temperature drop rate calculation. In another technical solution, the temperature data T of the loose layer within the same station number range with a time difference of less than 30 seconds is used. s With the temperature data of the compacted layer T r When grouped together, if multiple loose layer temperature data or multiple compacted layer temperature data exist within the same chainage range, the equivalent loose layer temperature T at the center point P0 of that chainage is calculated using the distance-weighted inverse proportional interpolation method. seq and equivalent compacted layer temperature T req Using the center point P0 of the station as the fusion benchmark, the dispersed multi-point temperature data are fused into an equivalent characteristic temperature through distance weighting and weighted averaging. This eliminates the randomness of single-point measurements and the non-uniformity of cross-sectional temperature distribution. Specifically, the center point P0 corresponding to the current station is determined, and then the planar distance d from each temperature measuring point of the loose layer and the temperature measuring point of the compacted layer to the center point is calculated. i The weight w corresponding to each measuring point is determined based on the distance. i The central control unit calculates the equivalent loose layer temperature T by weighting the temperature of all measuring points according to the weight ratio. seq and equivalent compacted layer temperature T req The system no longer uses data from a single measuring point, but instead combines two sets of equivalent temperature T. seq and T req The representative temperature is used in the subsequent calculation of the temperature drop rate V. T seq = Σ(w i ·T s,i ) / Σw i T req = Σ(w i ·T r,i ) / Σw i Where the weight wi =1 / d i 2 d i Let T be the planar distance from the i-th measuring point to the center point P0 of the chainage. The temperature field characteristics of the ultra-thin wear layer are that heat is conducted outward from the paving center. The closer the area is to the center, the more representative the temperature is of the true heat dissipation state of that chainage. The contribution of nearby measuring points is significant, while the contribution of distant measuring points decays rapidly. s,i T represents the temperature data of the i-th loose layer temperature measurement point. r,i For the temperature data of the i-th compaction layer temperature measuring point, the central control unit uses T... seq and T req The representative temperature data for this group was used to calculate the rate of temperature drop. After completing time synchronization (difference <30s) and initial spatial matching (within the same station number range), the central control unit identifies the number of temperature measuring points within that station number. If multiple T... s or multiple T r This triggers the interpolation process; The system automatically locates the geometric center point P0 of the station number and calculates the coordinates of each measuring point (X) using the coordinate data from the positioning receiver. i ,Y i Planar distance from P0(X0, Y0) ; Press w i =1 / d i 2 Calculate the weight of each measuring point, and then perform weighted summation and normalization on the temperatures of the loose layer and the compacted layer respectively to obtain T. seq and T req ; The system uses T seq Replace the original T s , with T req Replace the original T r To calculate the actual temperature drop rate V, for example, when a certain measuring point happens to be located in the segregation area or is shaded, its temperature may be abnormally low or high. If the data of this point is used directly, it will lead to serious deviation in the calculation of the temperature drop rate. After using the distance-weighted inverse proportional interpolation method, the contribution of abnormal measuring points is effectively suppressed by its weight, and the overall calculation result is closer to the true average temperature of the region.

[0035] The above technical solution can effectively reduce the calculation error caused by uneven distribution of measuring points and local temperature anomalies, and make the temperature drop rate V better reflect the overall cooling state of the station area. The distance weighted inverse interpolation method is simple to calculate, has high stability, and is easy to implement in engineering. It only needs to store the coordinates and temperature values ​​of each measuring point to calculate in real time, which is suitable for real-time processing on the construction site. The introduction of equivalent temperature improves the accuracy and reliability of temperature matching, and improves the overall control precision and construction quality.

[0036] During construction, satellite signals are easily blocked, leading to positioning interruptions. Relying solely on satellite positioning cannot guarantee continuous and reliable output, causing spatiotemporal matching failures and disruptions in coordinated control. In another technical solution, both the first and second positioning receivers are equipped with signal loss emergency modules. During normal operation, the system relies on satellite signals for positioning. When the positioning receiver cannot obtain a valid satellite signal, such as when the satellite signal is blocked, interfered with, or cannot obtain valid data, the signal loss emergency module automatically switches to the inertial navigation unit for position calculation. It achieves autonomous positioning and attitude detection by measuring three-axis acceleration and three-axis angular velocity, without relying on external signals. Position estimation is based on dead reckoning, which uses acceleration integration to obtain velocity and velocity integration to obtain displacement. This allows for continuous position estimation even when satellite signal lock is lost. Specifically, the last valid satellite positioning data frame before signal lock loss is used as the initial reference point (X0, Y0, Z0) and initial attitude angle. The inertial navigation unit continuously collects three-axis acceleration (α, β, γ) data. x , a y , a z ) and triaxial angular velocity (ω x , ω y , ω z Since acceleration and angular velocity are measured in the carrier coordinate system, the motion information in the carrier coordinate system needs to be converted into displacement in the construction plane coordinate system first through a coordinate transformation matrix. Then, the displacement is accumulated, and the velocity increment and attitude change in the carrier coordinate system are obtained through integration. This is then transformed back to the construction plane coordinate system through a coordinate transformation matrix, and the position coordinates (X, Y, φ) at the current moment are calculated by successive accumulation. t , Y t Z t This ensures that the calculated location is consistent with the road construction coordinate system; The first step is velocity recursion: V t = V t-1 +∫a·dt The second step is positional deduction: P t = P t-1 +∫V t ·dt Among them, V t Let P be the velocity vector at the current moment. t Given the current position vector, the inertial navigation unit outputs the calculated position coordinates at a frequency of not less than 10Hz until the satellite signal is restored. At the same time, the central control unit records the deviation between the calculated trajectory and the measured trajectory after the signal is restored, and uses it for subsequent inertial navigation zero-bias correction. After the satellite signal is recovered, the central control unit records the deviation between the inertial calculated trajectory and the measured satellite trajectory. Due to the cumulative error of the inertial navigation unit, the position deviation will gradually increase after a long period of calculation. The system uses this deviation information for the zero bias correction of the subsequent inertial navigation unit. By establishing an error model, the zero bias of the accelerometer and gyroscope is compensated online to improve the accuracy of the next emergency calculation. The first and second positioning receivers receive satellite signals at a frequency of ≥20Hz and output accurate position coordinates. At the same time, the central control unit records the attitude angle corresponding to each frame of positioning data for IMU zero bias correction. When the positioning receiver fails to receive a valid satellite signal for 3 consecutive frames (≤0.15s), the signal loss emergency module is immediately triggered, using the last frame of satellite positioning data (X0, Y0, Z0) and attitude angle before the loss of lock as the initial reference. The IMU acquires triaxial acceleration *a* and triaxial angular velocity *ω* at a frequency ≥10Hz. First, the attitude angle is updated by integrating the angular velocity, and a coordinate transformation matrix is ​​constructed to convert the acceleration *a* in the carrier coordinate system to the acceleration in the construction plane coordinate system. Then, integration is performed according to the formula, first integrating *a* to obtain *V*. t Then by V t Integrating to obtain P t Real-time output of calculated position coordinates; Once the satellite signal is restored, the central control unit will calculate position P. t Compared with the measured satellite position P real Compare and calculate the positional deviation ΔP = P t -P real This deviation is then used as the IMU zero-bias correction value and written into the filtering algorithm to correct the initial error of the next inertial calculation, thus preventing the cumulative error from continuing to expand.

[0037] The above technical solution can ensure continuous positioning in areas where satellite signals are easily blocked, such as under bridges, near tunnels, around tall buildings, and in densely wooded road sections. It avoids a series of problems caused by positioning interruption, such as interruption of paver elevation control, failure to record roller trajectory, and failure to match temperature data. The inertial navigation emergency positioning does not rely on external signals, has a fast response speed and high short-term accuracy. It can maintain centimeter-level positioning accuracy within tens of seconds of signal interruption, fully meeting the requirements of continuous construction of ultra-thin wear-resistant layers. This enables the overall positioning system to maintain stable, continuous, and reliable operation in complex construction site environments.

[0038] Traditional elevation adjustment rates are fixed and do not consider paver travel speed and deviation. Adjustments that are too fast are prone to overshoot, while adjustments that are too slow result in lag, making it difficult to maintain good elevation control under different working conditions and affecting the uniformity of the ultra-thin wearing course thickness. In another technical solution, when the central control unit sends an elevation adjustment command (screed height) to the paver control system, it no longer uses a fixed adjustment rate, but instead adjusts it according to the current paver travel speed v. p The adjustment rate v of the ironing plate is dynamically adjusted based on the elevation deviation value ΔH. adj This refers to the speed at which the ironing board moves up and down. v adj = v b ×(ΔH / ΔH ref )×(v ref / v p ), The adjustment rate is proportional to the current deviation ΔH; the larger the deviation, the faster the adjustment needs to be made to restore the design elevation as quickly as possible. The adjustment rate is also proportional to the current walking speed v. p Inversely proportional, the faster the walking speed, the slower the adjustment should be, in order to avoid drastic adjustments during rapid movement that would cause the ironing board to move too violently and create waves on the road surface; Among them, v b The baseline adjustment rate is 0.5-1.0 mm / s, and ΔH is the absolute value of the current elevation deviation in mm. ref The reference deviation value is 5mm, v ref The baseline paving speed is set at 3 m / min. When ΔH < 8 mm, it falls within the small deviation range and proportional control is used. This means the adjustment rate is directly proportional to the current deviation, resulting in a rapid response and quick correction of minor deviations. When ΔH ≥ 8 mm, it falls within the larger deviation range and proportional-integral (PI) control is used. An integral term is added to the proportional control, which accumulates historical deviation information, eliminates potential steady-state errors, ensures that the elevation accurately returns to the design value without leaving residual deviations, and simultaneously sends a deceleration warning to the paver control system to more smoothly complete larger elevation corrections. The central control unit compares the elevation values ​​in the paver's three-dimensional position coordinates with the design elevation in real time, calculates the absolute value of the elevation deviation ΔH, and simultaneously collects the real-time travel speed v through the paver's speed sensor. p and convert it to v ref A standardized unit (m / min); v b , ΔH, ΔH ref v ref v p Substituting into the calculation, we obtain the real-time adjustment rate v. adj , ensure v adjIt remains within the engineering safety range of 0.5-1.0 mm / s. The system switches strategies based on the magnitude of ΔH. When ΔH < 8mm, proportional control is used, with only v... adj For output, the ironing board is controlled to rise and fall at this rate to avoid overshoot caused by the integral stage and to achieve precise and stable control with small deviations; when ΔH≥8mm, proportional-integral control is used, at v adj Based on the proportional output, an integral term for elevation deviation is superimposed, and a deceleration warning is simultaneously sent to the paver control system, prompting the operator to reduce the speed of the paver. p Reduce the speed to below 3 m / min to allow sufficient response time for large deviation correction; The central control unit will adjust the rate v adj The control strategy and deceleration prompts (if any) are packaged into an elevation adjustment command and sent to the screed hydraulic control system of the paver. The hydraulic system drives the screed to complete the lifting and lowering action according to the command.

[0039] The above technical solution enables precise matching of elevation adjustment rate with real-time working conditions, avoiding overshoot or lag problems caused by fixed rate. It allows for smooth adjustment with small deviations and rapid and precise adjustment with large deviations. With speed prompts, it can significantly improve the uniformity of ultra-thin wear layer paving thickness and elevation control accuracy. Regardless of paving speed or deviation size, the system can automatically select the optimal adjustment strategy, resulting in better control and effectively improving road surface smoothness and construction quality.

[0040] During the operation of the paver, there is continuous vibration. The ultrasonic thickness gauge is prone to unstable contact between the probe and the road surface due to vibration, resulting in fluctuating and distorted measurement data. This makes it impossible to accurately reflect the real-time paving thickness and affects the accuracy of thickness control. In another technical solution, a buffer mounting bracket is provided between the ultrasonic thickness gauge and the screed. The buffer mounting bracket includes a fixed base, a guide column, and a shock-absorbing spring. The fixed base is the basic connecting component between the bracket and the paver screed, ensuring the overall structure is firm and reliable. The guide column is a guiding component used to limit the movement direction of the thickness gauge, ensuring that the thickness gauge can only move in the vertical direction. The shock-absorbing spring is an elastic component used to absorb and attenuate vibrations, reducing the transmission of paver vibrations to the thickness gauge. The ultrasonic thickness gauge is floatingly connected to the guide column through the shock-absorbing spring, meaning that the thickness gauge can move freely up and down along the guide column. This ensures that the detection end of the ultrasonic thickness gauge remains in contact with the surface of the loose paved layer with constant pressure during the paving process. During paver operation, the vibration generated by the machine body is significantly attenuated when transmitted to the shock-absorbing spring through the fixed base and guide column, significantly reducing the amount of vibration transmitted to the thickness gauge body. This allows the thickness gauge to maintain a stable detection state even in a continuous vibration environment.

[0041] The above technical solution can effectively isolate the impact of paver vibration on the thickness gauge, avoid unstable detection, data fluctuation or distortion caused by vibration, and ensure that the stable contact state ensures continuous, accurate and reliable thickness measurement data, providing real and effective data support for real-time control of paving thickness. The buffer support has a simple structure, is easy to install, has high reliability and is not easily damaged, and can work stably for a long time in the harsh environment of the construction site, improving the control accuracy of ultra-thin wear layer thickness and construction uniformity.

[0042] When the system experiences communication interruptions, positioning failures, sensor malfunctions, or unstable data links, it is prone to problems such as control confusion, data loss, and malfunctions. In another technical solution, the central control unit is equipped with a fault classification response module. This module pre-stores multiple fault levels, which are divided into four levels from highest to lowest according to their impact on construction safety and control accuracy. Level 1 faults have the most severe impact, while level 4 faults have the least. The fault levels are defined from highest to lowest as follows: Level 1 faults are core control failures, including communication interruptions between the central control unit and the paver control system or roller control system for more than 5 seconds, or failures of the central control unit's main processor. These faults prevent the system from sending control commands and are the most serious type of fault. When a Level 1 fault occurs in the central control unit, the last complete set of data before the interruption is immediately saved to the local data buffer to prevent data loss. The highest priority audible and visual alarm is sent to the field operation terminal, and the authority to issue additional compaction commands is temporarily switched to manual confirmation mode. The field operators judge whether to add compaction based on their experience. Level 1 faults ensure that data is not lost and construction can continue in extreme cases. Level 2 faults are positioning data failures, including the loss of satellite signal lock of the first or second positioning receiver and the inertial navigation unit's calculation time exceeding 30 seconds, or positioning data jumps exceeding a preset threshold. When the satellite signal loss exceeds 30 seconds, the cumulative error of inertial navigation may be too large, and the positioning data is no longer reliable. Positioning data jumps, i.e., position changes between adjacent moments exceeding a preset threshold such as 0.5m, indicate positioning abnormalities. Such faults result in the loss of position reference. When a Level 2 fault occurs in the central control unit, the calculation of the temperature drop rate and the automatic elevation adjustment are suspended. The last valid elevation command before the loss of lock is maintained to prevent incorrect adjustment. A positioning fault alarm is sent to the on-site operation terminal to prompt the operator to reduce speed or stop work until the signal is restored. The Level 2 fault prevents the road elevation from being out of control due to positioning errors. Level 3 faults are caused by abnormal sensor data, including: Both the first infrared temperature sensor and the second infrared temperature sensor are equipped with redundant temperature sensors. When the difference between the data collected by the primary sensor and the redundant sensor exceeds 5°C, the excessive difference in temperature sensor values ​​indicates that at least one of the sensors may be damaged or contaminated. If the difference between the data collected by the electromagnetic induction compaction meter and the radar compaction meter exceeds 3% of the design compaction degree, it indicates that there is an abnormality in the measurement system. If the ultrasonic thickness gauge data exceeds the preset threshold range for 3 consecutive seconds, it indicates that the probe is stuck or damaged, resulting in some monitoring data being unreliable. When a Level 3 fault occurs in the central control unit, for temperature sensors, it automatically switches to redundant sensor data or a calibration data source. For compaction gauges and ultrasonic thickness gauges, it suspends the issuance of control commands affected by the sensor (such as suspending additional compaction when the temperature is abnormal, or suspending compaction comparison when the compaction is abnormal) to avoid making decisions based on incorrect data. It also sends a specific sensor fault alarm to the field operation terminal, prompting the sensor to be replaced or cleaned. Level 3 faults ensure the reliability of sensor data. Level 4 faults are unstable data links, including communication interruptions between the central control unit and external networks such as cloud platforms and remote monitoring centers, or abnormal write speeds of local data buffers. Such faults do not affect core control functions, but may cause data to fail to be uploaded or stored. When a Level 4 fault occurs in the central control unit, all monitoring data is automatically stored in the local data buffer and automatically retransmitted to the data processing module of the central control unit after communication is restored. At the same time, the collection frequency of non-core data is reduced to alleviate the system load, and the integrity of data is guaranteed during Level 4 faults. When two or more faults occur simultaneously, the fault classification response module executes the corresponding handling strategies in descending order of fault level, and only executes the handling strategy corresponding to the highest level fault until that level fault is resolved before handling the next highest level fault. After the fault is resolved, the system automatically returns to normal operation mode. For example, if a level 1 communication interruption and a level 3 sensor malfunction occur simultaneously, the system will prioritize executing the handling strategy for the level 1 fault to save data and switch to manual mode, instead of simultaneously executing the automatic switching operation for the level 3 fault, thus avoiding multiple command conflicts. When all faults are resolved, the system automatically returns to normal operation mode.

[0043] In the above technical solution, the system can operate in an orderly, safe and reliable manner under various abnormal working conditions, avoiding the expansion of faults or data loss. The hierarchical handling strategy is highly targeted, logically clear and easy to operate, which can minimize the impact of faults on the construction process, significantly improve the robustness, safety and anti-interference ability of the system, and ensure the continuous, stable and reliable construction of the ultra-thin wear layer.

[0044] The number of devices and processing scale described herein are for the purpose of simplifying the description of the invention. Applications, modifications, and variations of the invention will be readily apparent to those skilled in the art.

[0045] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. Other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details shown and described herein.

Claims

1. A method for coordinated control of asphalt pavement paving and compaction processes, used for paving ultra-thin wearing courses with a thickness of 3-10 mm, characterized in that, Includes the following steps: Before the paver starts working, the chainage range of the road section to be paved, the design elevation of each chainage, and the design compaction degree are input to the central control unit. The lower limit of the allowable temperature for compaction is calibrated through field tests. The range of the lower limit of the allowable temperature for compaction is 100-110℃. The central control unit is used to receive monitoring data in real time, perform calculations and processing, and send control commands to the paver and roller. During the paving operation, the first positioning receiver installed on the paver acquires the paver's three-dimensional position coordinates in real time at a frequency of not less than 20Hz, and the first infrared temperature sensor installed on the paver acquires the surface temperature field data of the entire cross-section of the paved layer in real time as the loose layer temperature data T. s An ultrasonic thickness gauge installed on the paver acquires the thickness data of the loose paving layer in real time. During the compaction operation of the road roller, a second positioning receiver installed on the road roller acquires the three-dimensional position coordinates and running trajectory of the road roller in real time at a frequency of not less than 20Hz. A second infrared temperature sensor installed on the road roller acquires the surface temperature of the compacted road surface in real time as the temperature data T of the compacted layer. r The compaction gauge installed on the road roller obtains the compaction value of the road surface being rolled in real time; The central control unit receives and stores the paver's three-dimensional position coordinates and loose layer temperature data in real time. s Data on the thickness of the loose paving layer, the three-dimensional position coordinates and running trajectory of the roller, and the temperature data of the compacted layer (T). r The compaction value of the rolled pavement was also measured, and the first and second positioning receivers were synchronized in time. The temperature data T of the loose layer within the same station range with a time difference of less than 30 seconds was also collected. s With the temperature data of the compacted layer T r Grouped into one group, the actual temperature drop rate V = (T) of the asphalt mixture within that chainage range from the paving time to the compaction time is calculated based on the temperature data of that group. s -T r ) / Δt, where V is the actual temperature drop rate, and T s For loose layer temperature data, T r The data represents the temperature of the compacted layer, where Δt is the time difference between the acquisition of the temperature data of the loose layer and the temperature data of the compacted layer. The central control unit compares the received three-dimensional position coordinates of the paver with the chainage range and design elevation of the road section to be paved. When the deviation between the three-dimensional position coordinates of the paver and the design elevation exceeds ±5mm, it sends an elevation adjustment command to the paver control system. The central control unit compares the received compaction value of the rolled pavement with the design compaction value. When the compaction value of the rolled pavement is lower than the design compaction value, it looks up the corresponding loose layer temperature data T based on the station range of the substandard area. s Given the actual temperature drop rate V, predict the remaining time t that the substandard area can be compacted after the current moment. r = (T r -T min ) / V, where t r To be able to crush the remaining time, T r For the current compaction layer temperature data, T min This is the lower limit of the allowable temperature for compaction. If the remaining compaction time t is... r If the value is greater than zero, an additional compaction command is sent to the roller control system. The additional compaction command includes the number of additional compaction passes calculated based on the difference between the current compaction value and the design compaction value, with one additional compaction pass for every 1% difference below the design compaction value.

2. The method for coordinated control of asphalt pavement paving and compaction according to claim 1, characterized in that, The central control unit obtains the ambient temperature T at the construction site in real time. a Given the ambient wind speed W, a temperature difference-driven model based on Newton's law of cooling is used to compensate for the actual temperature drop rate V. The central control unit then uses the compensated temperature drop rate V. c Replace the actual temperature drop rate V with the prediction of the remaining time for compaction. V c = V·[1+k1·(T s -T a ) / (T s -T a )0+k2·(W / W0)], Among them (T) s -T a W0 is the reference temperature difference calibrated through field tests, ranging from 30-50℃; W0 is the reference wind speed, with a value of 2 m / s; k1 and k2 are dimensionless correction coefficients obtained through regression analysis, with k1 ranging from 0.1-0.3 and k2 ranging from 0.05-0.15; T a The unit is ℃, and W is in m / s.

3. The method for coordinated control of asphalt pavement paving and compaction according to claim 2, characterized in that, The central control unit has a built-in Kalman filter that processes the compacted layer temperature data sequence T obtained from multiple consecutive compaction times within the same pile number range. r(k) and the compensated temperature drop rate sequence V calculated at the corresponding time. c(k) As the observation input, a state transition matrix considering the thermal inertia of the asphalt mixture is established. The temperature drop rate is then smoothly estimated using a Kalman filter recursive algorithm to obtain the noise-reduced temperature drop rate V. kf The central control unit adopts V kf Temperature drop rate V after replacement compensation c To predict the remaining time that can be crushed, The state equation and observation equation of the Kalman filter are as follows: V k = A·V k-1 +B·u k-1 +w k-1 , V c(k) = V k +v k , Where A is the state transition matrix, B is the control matrix, u is the rate of change of ambient temperature, and w and v are the process noise and observation noise, respectively.

4. The method for coordinated control of asphalt pavement paving and compaction according to claim 1, characterized in that, The minimum allowable temperature for compaction, T min Based on the penetration grade P of the asphalt mixture, the paving thickness h, and the ambient temperature T a Dynamic adjustment; the central control unit adopts a dynamically adjusted T min 'Predict the remaining time that it can be crushed,' T min ' = T base +α·(P0-P)+β·(h0-h)+γ·(T a0 -T a ), Where T base The lower limit of the reference temperature is determined through field testing and the value range is 100-110℃. P is the asphalt penetration, in units of 0.1 mm, P0 is the reference penetration, with a value of 80, h is the paving thickness, in units of mm, h0 is the reference thickness, with a value of 5 mm, and T... a The ambient temperature is expressed in °C (°C) or T. a0 The reference ambient temperature is 20℃. α, β, and γ are material property coefficients. The value of α ranges from 0.1 to 0.3℃ per unit penetration, the value of β ranges from 1.5 to 2.5℃ / mm, and the value of γ ranges from 0.3 to 0.7℃ / ℃.

5. The method for coordinated control of asphalt pavement paving and compaction according to claim 1, characterized in that, The calculation of the additional compaction passes N adopts a logarithmic model based on the compaction degree growth curve: N = ceil[a·ln((D des -D0) / (D des -D act ))], Among them, D des To design the compaction degree, D act D0 is the current compaction degree value, D0 is the initial compaction degree benchmark value obtained through field test sections, a is the compaction efficiency coefficient with a value range of 1.2-2.0, ln is the natural logarithm, and ceil is the round-up value, and is calculated based on the remaining compaction time t. r Less than the preset safety time threshold T safe When N is incremented by 1, T safe The value range is 8-12s.

6. The method for coordinated control of asphalt pavement paving and compaction according to claim 1, characterized in that, Temperature data T of the loose layer within the same station number range and with a time difference of less than 30 seconds s With the temperature data of the compacted layer T r When grouped together, if multiple loose layer temperature data or multiple compacted layer temperature data exist within the same chainage range, the equivalent loose layer temperature T at the center point P0 of that chainage is calculated using the distance-weighted inverse proportional interpolation method. seq and equivalent compacted layer temperature T req , T seq = Σ(w i ·T s,i ) / Σw i , T req = Σ(w i ·T r,i ) / Σw i , Where the weight w i =1 / d i 2 d i Let T be the planar distance from the i-th measuring point to the station center point P0. s,i T represents the temperature data of the i-th loose layer temperature measurement point. r,i For the temperature data of the i-th compaction layer temperature measuring point, the central control unit uses T... seq and T req The representative temperature data for this group was used to calculate the rate of temperature drop.

7. The method for coordinated control of asphalt pavement paving and compaction according to claim 1, characterized in that, Both the first and second positioning receivers are equipped with a signal loss emergency module. When the positioning receiver cannot obtain a valid satellite signal, the signal loss emergency module automatically switches to the inertial navigation unit to calculate the position. Position estimation is based on dead reckoning, using the last valid satellite positioning data frame before signal loss as the initial reference point (X0, Y0, Z0) and initial attitude angle. The inertial navigation unit collects three-axis acceleration (α) in real time. x , a y , a z ) and triaxial angular velocity (ω x , ω y , ω z The velocity increment and attitude change in the carrier coordinate system are obtained through integration, and then transformed to the construction plane coordinate system through a coordinate transformation matrix. The position coordinates (X, Y, F) at the current moment are calculated by accumulating these coordinates. t , Y t Z t ); V t = V t-1 +∫a·dt, Q t =P t-1 +∫V t ·dt, Among them, V t Let P be the velocity vector at the current moment. t Given the current position vector, the inertial navigation unit outputs the calculated position coordinates at a frequency of not less than 10Hz until the satellite signal is restored. At the same time, the central control unit records the deviation between the calculated trajectory and the measured trajectory after the signal is restored, and uses it for subsequent inertial navigation zero-bias correction.

8. The method for coordinated control of asphalt pavement paving and compaction according to claim 1, characterized in that, When the central control unit sends an elevation adjustment command to the paver control system, it also considers the current paver travel speed v. p The adjustment rate v of the ironing plate is dynamically adjusted based on the elevation deviation value ΔH. adj , v adj = v b ×(ΔH / ΔH ref )×(v ref / v p ), Among them, v b The baseline adjustment rate is 0.5-1.0 mm / s, and ΔH is the absolute value of the current elevation deviation in mm. ref The reference deviation value is 5mm, v ref The baseline paving speed is set at 3 m / min. When ΔH < 8 mm, proportional control is used, and when ΔH ≥ 8 mm, proportional-integral control is used, and a deceleration warning is issued to the paver control system at the same time.

9. The method for coordinated control of asphalt pavement paving and compaction according to claim 1, characterized in that, A buffer mounting bracket is provided between the ultrasonic thickness gauge and the screed. The buffer mounting bracket includes a fixed base, a guide column, and a shock-absorbing spring. The ultrasonic thickness gauge is floatingly connected to the guide column through the shock-absorbing spring, so that the probe end of the ultrasonic thickness gauge always keeps in contact with the surface of the loosely laid layer during the paving process and the pressure is constant.

10. The method for coordinated control of asphalt pavement paving and compaction according to claim 1, characterized in that, The central control unit is equipped with a fault classification response module, which pre-stores multiple fault levels. The fault levels are defined from high to low as follows: Level 1 faults are core control failures, including communication interruptions between the central control unit and the paver control system or roller control system for more than 5 seconds, or failures of the central control unit's main processor. When a Level 1 fault occurs in the central control unit, it immediately saves the last complete set of data before the interruption to the local data buffer, sends the highest priority audible and visual alarm to the field operation terminal, and temporarily switches the permission to issue additional compaction commands to manual confirmation mode, allowing the field operator to judge whether to add compaction based on experience. Level 2 faults are positioning data failures, including the loss of satellite signal lock of the first or second positioning receiver and the inertial navigation unit's calculation time exceeding 30 seconds, or positioning data jumps exceeding a preset threshold. When a level-two fault occurs in the central control unit, the calculation of the temperature drop rate and the automatic elevation adjustment are suspended. The last valid elevation command before the lockout is lost is maintained, and a positioning fault alarm is sent to the field operation terminal, prompting the operator to reduce speed or stop the operation until the signal is restored. Level 3 faults are caused by abnormal sensor data, including: Both the first infrared temperature sensor and the second infrared temperature sensor are equipped with redundant temperature sensors. When the difference between the data collected by the primary sensor and the redundant sensor exceeds 5°C. The difference between the data collected by the electromagnetic induction compaction meter and the radar compaction meter exceeds 3% of the design compaction degree; The ultrasonic thickness gauge data exceeded the preset threshold range for 3 consecutive seconds. When a Level 3 fault occurs in the central control unit, it automatically switches to redundant sensor data or a verification data source, suspends the issuance of control commands affected by the sensor, and sends a specific sensor fault alarm to the field operation terminal, prompting the sensor to be replaced or cleaned. Level 4 faults are caused by unstable data links, including communication interruptions between the central control unit and the external network, or abnormal write speeds of the local data buffer. When a Level 4 fault occurs in the central control unit, all monitoring data is automatically stored in the local data buffer and automatically retransmitted to the data processing module of the central control unit after communication is restored. At the same time, the collection frequency of non-core data is reduced to alleviate the system load. When two or more faults occur simultaneously, the fault classification response module executes the corresponding handling strategies in descending order of fault level, and only executes the handling strategy corresponding to the highest level fault until the fault of that level is resolved before handling the next highest level fault. After the fault is resolved, the system automatically returns to normal operation mode.