Intelligent ash supply control system based on plastering quality feedback

Abstract

The application discloses an intelligent mortar feeding control system based on mortar quality feedback, and solves the problem that the mortar feeding system of an existing mortar robot system cannot adapt to the difference in rheological characteristics of different types of mortar, resulting in a decrease in mortar quality or even failure to normally construct. The system comprises a mortar-spread surface quality condition identification module, a mortar feeding pipeline mortar rheological parameter identification module, a diagnosis decision module and a mortar feeding regulation and control module.

Description

Technical Field

[0001] This invention relates to the field of construction automation technology, specifically to an intelligent mortar supply control system based on plastering quality feedback, used for closed-loop control of the mortar supply system during the automated construction process of a plastering robot system, so as to maintain the rheological properties of the mortar in a suitable construction state. Background Technology

[0002] A complete plastering robot system consists of two parts: a mortar supply system and a plastering system. The applicant has already described the plastering system and its core plastering actuator in patent documents such as CN117549274A and CN118288295A, and will not repeat them here. As for the mortar supply system, most systems currently use mature equipment, such as the screw pump-type mortar conveyor currently used by the applicant.

[0003] like Figure 1 As shown, the screw pump type mortar conveyor mainly consists of a silo, a vibrating motor, a screw pump, and a mortar supply pipeline. The silo is used to hold pre-mixed mortar, and a vibrating motor is installed at the bottom to prevent mortar bridging. The screw pump is connected below the silo. The screw pump body has an eccentric rotor structure with a helical metal rotor and a rubber stator. The outlet of the screw pump is connected to the plastering actuator of the plastering system via the mortar supply pipeline, which is equipped with a pressure gauge. During operation, the mortar falls from the silo into the screw pump under the assistance of gravity and the vibrating motor. The rotor rotates eccentrically in the stator, forming a progressively advancing sealed cavity between the two, pumping the mortar out in a volumetric positive displacement manner. The mortar is finally delivered to the plastering actuator via the mortar supply pipeline.

[0004] Existing plastering robot systems primarily use cement mortar as the target medium for system design, parameter matching, and control strategy calibration. The rheological properties of cement mortar are relatively stable within the construction time window, and its setting time is relatively long. Plastering robot systems can achieve relatively stable plastering results with fixed or semi-fixed operating parameters. However, with the construction industry's increasing demands for lightweight, energy-saving, and environmentally friendly materials, lightweight gypsum mortar and desulfurized gypsum mortar are gradually replacing traditional cement mortar as the mainstream materials for interior wall plastering. Through practical experience, the applicant has found that while their plastering robot system can meet the plastering requirements when using cement mortar, the plastering quality becomes significantly insufficient when switching to lightweight gypsum mortar. Defects such as localized mortar peeling and severely substandard surface smoothness appear on the plastered surface. Furthermore, when switching to desulfurized gypsum mortar, the plastering operation cannot even proceed normally.

[0005] Research and analysis revealed that the direct cause of the aforementioned problems lies in the rheological properties of the mortar, which directly determine its performance during application to walls. Specifically, yield stress affects the adhesion between the mortar and the substrate, as well as its resistance to sagging, while plastic viscosity influences the spreading and finishing effects of the mortar under the action of the plastering mechanism. The rheological parameters of different types of mortar vary significantly: lightweight gypsum mortar has lower density and insufficient yield stress, resulting in weak adhesion and poor resistance to sagging after application, easily leading to localized peeling and uneven surfaces; the rheological properties of desulfurized gypsum mortar differ even more significantly from those of cement mortar, making it even more difficult to form a qualified plaster layer under current working conditions.

[0006] Further analysis reveals that the rheological properties of mortar are not entirely uncontrollable inherent properties. Gypsum-based mortars generally exhibit strong thixotropy, and their rheological state is significantly influenced by the shear history during pumping—the screw pump speed determines the shear rate and duration experienced by the mortar within the screw pump and pipeline, thus affecting the degree of damage and recovery of the mortar's microstructure, ultimately altering its yield stress and plastic viscosity upon reaching the plastering actuator. This means that, theoretically, proper adjustment of the mortar supply parameters can actively intervene in the mortar's rheological state to a certain extent. Furthermore, due to the rapid hydration reaction rate of gypsum-based mortars, their rheological properties exhibit a continuous changing trend within the construction time window. The rheological state of the same batch of mortar arriving at the plastering actuator at different times may have already changed significantly. This means that even if optimal parameter matching is achieved at a certain moment, this parameter combination will gradually become ineffective as the mortar's rheological properties change over time. Therefore, the mortar supply system needs to possess the ability to continuously track and dynamically adjust these parameters.

[0007] However, the control parameters of existing screw pump mortar conveyors (screw pump speed, air pump start / stop control) are fixed parameter combinations empirically tuned based on the rheological properties of cement mortar. These parameters cannot sense the actual rheological state of the mortar, nor can they adaptively adjust the supply parameters to intervene in and optimize the mortar's rheological state according to changes in mortar type and rheological properties. Even with the introduction of rheological parameter monitoring at the pipeline end, the mortar still undergoes scraping action by the plastering actuator from pipeline delivery to wall application. During scraping, the mortar is subjected to secondary shearing and compaction, further altering its rheological state. Coupled with the combined effects of external factors such as the water absorption of the wall substrate and ambient temperature and humidity, a complex nonlinear mapping relationship exists between the rheological parameters measured in the pipeline and the final construction performance of the mortar after application. Relying solely on pipeline-end parameter monitoring is insufficient to effectively guarantee construction quality. Therefore, this limits the compatibility of plastering robot systems with various mortar materials and the stability of construction quality. Summary of the Invention

[0008] The purpose of this invention is to provide an intelligent mortar supply control system based on plastering quality feedback, which solves the problem that the mortar supply system of existing plastering robot systems cannot adapt to the differences in the rheological properties of different types of mortar, resulting in a decline in plastering quality or even failure to perform normal construction.

[0009] This invention provides an intelligent mortar supply control system based on plastering quality feedback, comprising: a plastered surface quality status identification module, used to identify whether there is a quality deviation in the plastered surface based on the detection data obtained by a plastering quality detection device through real-time detection of the plastered surface; and a mortar rheological parameter identification module for the mortar supply pipeline, used to identify whether there is a quality deviation in the plastered surface based on the detection signals collected by pressure sensors at both ends of the effective measuring pipe section in the mortar supply pipeline and the pumping operation parameters of the mortar supply system during the process of conveying mortar from the mortar supply system to the plastering actuator through the mortar supply pipeline. The system identifies the rheological parameters of the mortar in the mortar supply pipeline; the diagnostic decision module is used to determine whether the quality deviation is attributable to a change in the rheological properties of the mortar when the quality deviation is identified by the plastered surface quality condition identification module, based on a preset association rule between the quality deviation and the rheological parameters; and when the quality deviation is determined to be attributable to a change in the rheological properties of the mortar, it generates a corresponding mortar supply control decision; the mortar supply control module is used to generate a mortar supply control command based on the mortar supply control decision and output it to the mortar supply system to adjust the rheological properties of the mortar in the mortar supply pipeline.

[0010] As an optimization and / or instantiation of the above-mentioned intelligent mortar supply control system based on plastering quality feedback, further: the rheological parameters include yield stress τ, the time rate of change of yield stress τ dτ / dt, plastic viscosity μ, and the time rate of change of plastic viscosity μ dμ / dt; the mortar rheological parameter identification module of the mortar supply pipeline models the mortar as a rheological constitutive model with yield stress, and obtains the yield stress τ and plastic viscosity μ online by solving the laminar flow equation of the circular pipe based on the rheological constitutive model, according to the pressure difference ΔP measured by the pressure sensors at both ends of the effective measurement pipe section, the mortar volume flow rate Q in the pipe converted from the pumping operation parameters, and the pipeline geometric parameters of the effective measurement pipe section.

[0011] As an optimization and / or instantiation of the above-mentioned intelligent ash supply control system based on plastering quality feedback, further: the rheological constitutive model is the Bingham plastic fluid model; the online solution establishes the relationship between volumetric flow rate Q and pressure difference ΔP based on the Buckingham-Reiner equation: Q=(πR 4 ΔP) / (8μL)·[1-(4 / 3)(τ / τ_w)+(1 / 3)(τ / τ_w) 4], where R is the inner radius of the effective measuring pipe section, L is the length of the effective measuring pipe section, and τ_w=RΔP / (2L) is the shear stress of the pipe wall; the mortar rheological parameter identification module of the ash supply pipeline periodically applies a preset amplitude speed step disturbance to the pumping device of the ash supply system, and collects the corresponding pressure difference ΔP1, ΔP2 and the volumetric flow rate Q1, Q2 converted from the pumping operation parameters under at least two different pumping device speed conditions. For each condition, a corresponding flow equation is established based on the Buckingham-Reiner equation, and the obtained at least two equations are combined to form an equation system, and the yield stress τ and plastic viscosity μ are solved online.

[0012] As an optimization and / or instantiation of the above-mentioned intelligent mortar supply control system based on plastering quality feedback, further: the quality deviation includes the surface roughness deviation of the plastered surface; the preset association rule includes: when the surface roughness of the plastered surface exceeds the preset allowable range, if the yield stress τ and / or the plastic viscosity μ deviate from their respective preset reference values, and the absolute values ​​of the time change rate dτ / dt of the yield stress τ and / or the time change rate dμ / dt of the plastic viscosity μ exceed their respective preset thresholds, then the quality deviation is determined to be due to the change in the rheological properties of the mortar.

[0013] As an optimization and / or instantiation of the aforementioned intelligent mortar supply control system based on plastering quality feedback, the diagnostic decision module is further configured to generate a preventative mortar supply control decision and output it to the mortar supply control module when one of the following conditions is met, provided that the quality deviation of the plastered surface has not yet been identified by the quality condition identification module: Condition 1: The absolute values ​​of the time-varying rate of yield stress τ (dτ / dt) and / or the time-varying rate of plastic viscosity μ (dμ / dt) continuously exceed their respective preset trend thresholds for a preset time; Condition 2: The normalized comprehensive deviation index S continuously exceeds the preset deviation threshold for a preset time, wherein the normalized comprehensive deviation index S = (dτ / dt / Δτ_ref) 2 +(dμ / dt / Δμ_ref) 2 Where Δτ_ref is a reference value used to normalize the yield stress over time, and Δμ_ref is a reference value used to normalize the plastic viscosity over time.

[0014] As an optimization and / or instantiation of the above-mentioned intelligent ash supply control system based on plastering quality feedback, further: the ash supply control command includes at least one of the following: a command to adjust the amount of water added to the ash supply system; a command to adjust the stirring speed of the stirring mechanism in the ash supply system; a command to adjust the feeding pressure and / or feeding flow rate of the ash supply system.

[0015] As an optimization and / or instantiation of the above-mentioned intelligent ash supply control system based on plastering quality feedback, further: the rheological parameters include yield stress τ, the time-varying rate of change of yield stress τ dτ / dt, plastic viscosity μ, and the time-varying rate of change of plastic viscosity μ dμ / dt; the ash supply control module generates the ash supply control command according to the following strategy based on the deviation direction of the rheological parameters indicated in the ash supply control decision: when the time-varying rate of change of yield stress τ dτ / dt is positive and exceeds a preset threshold, an command to increase the water addition and an command to increase the stirring speed are generated, and an command to increase the supply pressure is generated to compensate for the increase in pipeline resistance; when the plastic viscosity μ is higher than the upper limit of the preset benchmark value but the time-varying rate of change of yield stress τ dτ / dt does not exceed the preset threshold, an command to increase the water addition and an command to increase the supply pressure are generated; when the yield stress τ and / or the plastic viscosity μ are lower than their respective lower limits of the preset benchmark value, an command to decrease the water addition and / or an command to reduce the supply flow rate are generated.

[0016] As an optimization and / or instantiation of the above-mentioned intelligent plastering supply control system based on plastering quality feedback, the plastering quality detection device further includes a surface detection sensor installed on the plastering execution mechanism and moving in linkage with the plastering execution mechanism; the plastered surface quality condition identification module identifies the quality deviation based on the detection data obtained by the surface detection sensor.

[0017] As an optimization and / or instantiation of the above-mentioned intelligent mortar supply control system based on plastering quality feedback, further: the surface detection sensor is an industrial camera, the detection data is image data of the plastered surface, and the plastered surface quality condition recognition module calculates the surface roughness of the plastered surface by performing image texture analysis on the image data.

[0018] As an optimization and / or instantiation of the above-mentioned intelligent mortar supply control system based on plastering quality feedback, further: the surface detection sensor is a laser profile sensor, the detection data is surface profile data, and the plastered surface quality condition identification module calculates the surface roughness based on the surface profile data.

[0019] As an optimization and / or instantiation of the above-mentioned intelligent ash supply control system based on plastering quality feedback, further: the effective measuring pipe section is a straight pipe section in the ash supply pipeline; a flow stabilizing section is provided between the effective measuring pipe section and the outlet of the ash supply system, and the length of the flow stabilizing section is not less than a preset multiple of the inner diameter of the effective measuring pipe section.

[0020] The intelligent mortar supply control system based on plastering quality feedback of the present invention establishes a complete closed-loop control link by setting up a plastered surface quality condition identification module, a mortar rheological parameter identification module for the mortar supply pipeline, a diagnostic decision module, and a mortar supply control module. This link includes the detection of the quality of the plastered surface, the online identification of the mortar rheological parameters of the mortar supply pipeline, the correlation diagnosis of quality deviation and rheological characteristic changes, and finally the adaptive adjustment of the mortar supply system parameters. The system incorporates several key features. First, a mortar rheological parameter identification module for the mortar supply pipeline enables the system to perceive the rheological properties of the mortar online. Second, a module for identifying the quality of plastered surfaces directly extracts feedback signals from the actual quality of the plastered surface, avoiding the limitations of relying solely on pipeline-end rheological parameter monitoring, which cannot directly reflect the final plastering quality. Third, a diagnostic decision module uses preset association rules to correlate quality deviations with changes in rheological parameters, ensuring that mortar supply control is only triggered when the quality deviation is indeed caused by changes in the mortar's rheological properties, thus preventing mis-adjustments. Fourth, a mortar supply control module adjusts the parameters of the mortar supply system based on the control decisions generated by the diagnostic decision module, bringing the rheological properties of the mortar in the supply pipeline back to a suitable state for construction. Therefore, this invention's intelligent mortar supply control system based on plastering quality feedback enables the plastering robot system to adaptively adjust supply parameters when facing different types of mortar, improving the system's compatibility with various mortar materials and the stability of construction quality. This allows the plastering robot system to achieve good plastering quality when using different types of mortar, such as lightweight gypsum mortar and desulfurized gypsum mortar. Meanwhile, since the above-mentioned closed-loop control link runs continuously during construction, it can track the continuous changes in the rheological properties of the same batch of mortar due to factors such as hydration reaction within the construction time window, dynamically adjust the mortar supply parameters to maintain the time stability of the mortar rheological state, and avoid the gradual deterioration of plastering quality due to the drift of mortar rheological properties over time.

[0021] Furthermore, the diagnostic decision module can generate preventative mortar supply control decisions in advance based on the changing trends of rheological parameters, even before the quality deviation is identified by the plastered surface quality condition identification module. This prevents adverse changes in mortar rheological properties before quality defects appear, achieving proactive preventative control of plastering quality and further improving the stability of construction quality.

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Additional aspects and advantages provided by the present invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice. Attached Figure Description

[0023] The accompanying drawings, which form part of this specification, are used to aid in understanding the invention. The contents provided in the drawings and their related descriptions in this specification can be used to explain the invention, but do not constitute an undue limitation of the invention.

[0024] Figure 1 This is a physical image of the screw pump-type mortar conveyor used by the applicant prior to the filing date of this invention.

[0025] Figure 2 This is a physical diagram of the plastering execution mechanism and the plastering pipeline before the application date of this invention.

[0026] Figure 3 This is a photograph of a plastered surface that the applicant had already applied using gypsum mortar before the application date of this invention. Figure 3 Image A shows a finished plastered surface when using lightweight gypsum mortar. Figure 3 B is a photograph of the plastered surface that has already been plastered when using desulfurized gypsum mortar.

[0027] Figure 4 These are images captured using an industrial camera in an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of the effective measurement pipe section in an embodiment of the present invention.

[0029] Figure 6 This is a PID (Pipeline and Instrumentation) diagram of the ash supply system in an embodiment of the present invention.

[0030] Figure 7 This is a structural diagram of the intelligent ash supply control system according to an embodiment of the present invention.

[0031] The components in the diagram are labeled as follows: screw pump mortar conveyor 1, silo 11, screw pump 12, mortar supply pipeline 13, effective measuring pipe section 131, pressure sensor 132, clean water tank 141, metering pump 142, electromagnetic flowmeter 143, electromagnetic shut-off valve 144, spray head 145, mixing motor 151, mixing blades 152, electrically controlled proportional pressure regulating valve 161, and plastering actuator 2. Detailed Implementation

[0032] The present invention will now be clearly and completely described in conjunction with the accompanying drawings. Those skilled in the art will be able to implement the present invention based on these descriptions. Before describing the present invention in conjunction with the accompanying drawings, it should be particularly noted that:

[0033] The technical solutions and features provided in the various sections, including the following description, can be combined with each other without conflict. Furthermore, where possible, these technical solutions, features, and related combinations can be given specific technical subject matter and protected by relevant patents.

[0034] The embodiments of the present invention described below are generally only some embodiments and not all embodiments. Based on these embodiments, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of patent protection.

[0035] The terms "comprising," "including," "having," and any variations thereof in this specification, the corresponding claims, and related sections are intended to cover non-exclusive inclusion. Other related terms and units can be reasonably interpreted based on the relevant content provided in this specification.

[0036] A complete plastering robot system comprises two parts: a mortar supply system and a plastering system. In the intelligent mortar supply control system based on plastering quality feedback described in this invention, the pumping device of the mortar supply system is a positive displacement pump. A positive displacement pump has a fixed theoretical displacement per revolution, and its volumetric flow rate has a stable proportional relationship with its rotational speed. This allows the volumetric flow rate of mortar in the pipe to be directly calculated from the pumping operating parameters (rotational speed). Positive displacement pumps that meet the above conditions include, but are not limited to, screw pumps 12, gear pumps, peristaltic pumps, plunger pumps, and other types. This embodiment uses the screw pump type mortar conveyor 1 (e.g., [missing information]) used in the applicant's practice. Figure 1 As shown in the figure, a specific example of a mortar supply system will be described in detail. The screw pump type mortar conveyor 1 is connected to the plastering actuator 2 of the plastering system via a mortar supply pipeline 13 (see Figure 2). Figure 2 (As shown). Implementation methods using other types of positive displacement pumps as pumping devices can be deduced by analogy from the principles described in this embodiment.

[0037] like Figure 1 As shown, the screw pump type mortar conveyor 1 mainly consists of a silo 11, a vibrating motor, a screw pump 12, and a mortar supply pipeline 13. The silo 11 is used to hold pre-mixed mortar, and a vibrating motor is installed at the bottom to prevent mortar bridging. The screw pump 12 is connected below the silo 11. The screw pump 12 has an eccentric rotor structure with a helical metal rotor and a rubber stator inside the pump body. The outlet of the screw pump 12 is connected to the plastering actuator 2 of the plastering system via the mortar supply pipeline 13, which is equipped with a pressure gauge. During operation, the mortar falls from the silo 11 into the screw pump 12 under the assistance of gravity and the vibrating motor. The rotor rotates eccentrically within the stator, forming a progressively advancing sealed cavity between the two, pumping the mortar out in a volumetric positive displacement manner. The mortar is finally delivered to the plastering actuator 2 via the mortar supply pipeline 13.

[0038] Pre-mixed mortar enters the hopper 11 of the screw pump mortar conveyor 1, and is then pumped out by the screw pump 12 via a volumetric pump and delivered to the plastering actuator 2 through the mortar supply pipeline 13. The plastering actuator 2 drives the outlet of the mortar supply pipeline 13 to move horizontally and repeatedly, so that the mortar is evenly distributed in the plastering actuator 2 (horizontal distributor), and finally scraped onto the wall surface by the plastering actuator 2. Since the yield stress and plastic viscosity of cement mortar are relatively stable within the construction time window, the mortar supply system can maintain a qualified construction effect by using a fixed combination of control parameters (screw pump 12 speed, etc.).

[0039] However, with the construction industry's increasing demands for lightweight, energy-saving, and environmentally friendly materials, lightweight gypsum mortar and desulfurized gypsum mortar are gradually replacing traditional cement mortar as the mainstream materials for interior wall plastering. Through practical experience, the applicant found that while its plastering robot system could meet the plastering requirements when using cement mortar, the plastering quality was significantly compromised when switching to lightweight gypsum mortar. Defects such as localized mortar peeling and severely substandard surface smoothness were observed on the plastered surfaces (see...). Figure 3 (As shown in A); and when further switched to desulfurized gypsum mortar, plastering work could not even be carried out normally (see Figure A). Figure 3 As shown in B).

[0040] The direct cause of the above problems lies in the fact that the rheological properties of the mortar directly determine its performance during application to the wall. Specifically, yield stress affects the adhesion between the mortar and the substrate, as well as its resistance to sagging, while plastic viscosity affects the spreading and finishing effect of the mortar under the action of the plastering actuator 2. The rheological parameters of different types of mortar vary significantly: lightweight gypsum mortar has lower density and insufficient yield stress, resulting in weak adhesion and poor resistance to sagging after application, easily leading to localized peeling and uneven surfaces; the rheological properties of desulfurized gypsum mortar differ even more significantly from those of cement mortar, making it more difficult to form a qualified plaster layer under current conditions. Furthermore, gypsum mortar has strong thixotropy and a rapid hydration reaction rate, and its rheological properties continuously change within the construction time window, requiring the mortar supply system to have the ability to continuously track and dynamically adjust these properties.

[0041] To quantitatively verify the time-varying law of the rheological properties of the above-mentioned gypsum mortar, the applicant conducted a comparative measurement experiment on the consistency change over time of two typical gypsum mortars. The experiment used lightweight gypsum mortar (Mianzhu Huaxin Technology, water-cement ratio 5:10) and desulfurized gypsum mortar (Sichuan Tongqing Nanfeng, water-cement ratio 6:10). After thorough mixing according to their respective mix proportions, periodic consistency measurements were performed according to GB / T17669.4-1999 "Determination of Physical Properties of Building Gypsum Paste". The experimental results are shown in Table 1.

[0042] Table 1: Measurement data on the consistency of two types of gypsum mortar over time

[0043] time Lightweight gypsum consistency Consistency of desulfurized gypsum Remark 10:05 7.9 10:13 9.0 10:18 7.8 10:23 8.2 10:28 7.9 10:33 9.6 10:37 9.2 10:42 7.3 10:48 9.7 10:56 7.3 10:57 7.4 shock 11:00 8.5 11:01 8.5 shock 11:05 7.0 11:13 8.6 11:25 6.5 11:29 8.2 11:35 6.2 11:40 8.2 11:45 6.0 11:50 8.2 12:45 4.8 12:48 6.8 14:10 Solidification and Softening Solidification and heating

[0044] Table 1 shows that: (1) the consistency of both types of gypsum mortar decreased monotonically over time, meaning that the mortar continued to thicken and its fluidity continued to decrease within the construction time window, indicating that its yield stress and plastic viscosity were in a time-varying process of continuous increase; (2) the rheological properties of the two types of mortar differed significantly: in the early stage of construction, the consistency of desulfurized gypsum mortar (about 9.0) was significantly higher than that of lightweight gypsum mortar (about 7.9), indicating that the initial fluidity of desulfurized gypsum mortar was better but its yield stress was lower, making it more prone to sagging after being applied to the wall; as the hydration process progressed, the consistency of both types of mortar decreased rapidly, with the consistency of desulfurized gypsum mortar decreasing more rapidly. At approximately 10:33, the consistency rose to 9.6 and then quickly dropped to 9.2 at 10:37. Subsequently, it rose slightly to 9.7 at 10:48, demonstrating the strong thixotropic properties of gypsum mortar and its rheological state being sensitive to shear history (the “vibration” note in the table also confirms the immediate impact of external vibration on the consistency measurement value); (3) Both types of mortars underwent coagulation and heat release at approximately 14:10. However, the lightweight gypsum mortar exhibited soft heat release during coagulation, while the desulfurized gypsum mortar exhibited hard heat release during coagulation, indicating that there is an essential difference in the microstructure of the hydration products of the two mortars. The desulfurized gypsum mortar had a higher hardness after coagulation.

[0045] To address the above problems, embodiments of the present invention provide an intelligent plastering supply control system based on plastering quality feedback. For example... Figure 7 As shown, the intelligent ash supply control system includes a hardware platform layer and a functional module layer. The hardware platform layer is built based on hardware components such as processors, memory, communication interfaces, and I / O interfaces. The processor runs the various functional modules in the functional module layer, the memory provides data access, and the communication interface and I / O interface enable external communication and signal input / output with the ash supply system and plastering system.

[0046] The functional module layer specifically includes: a plastered surface quality condition identification module, used to identify whether there is a quality deviation in the plastered surface based on the detection data obtained by the plastering quality detection device in real time detection of the plastered surface; a mortar rheological parameter identification module for the mortar supply pipeline, used to identify the rheological parameters of the mortar in the mortar supply pipeline 13 online based on the detection signals collected by the pressure sensors at both ends of the effective measuring pipe section 131 in the mortar supply pipeline 13 and the pumping operation parameters of the mortar supply system during the process of mortar being transported to the plastering execution mechanism 2 through the mortar supply pipeline 13; a diagnostic decision module, used to determine whether the quality deviation is attributed to the change in the rheological properties of the mortar based on the preset correlation rules between the quality deviation and the rheological parameters when the plastered surface quality condition identification module identifies a quality deviation, and to generate a corresponding mortar supply control decision when it is determined to be attributed to the change in the rheological properties; and a mortar supply control module, used to generate a mortar supply control command based on the mortar supply control decision and output it to the mortar supply system to adjust the rheological properties of the mortar in the mortar supply pipeline 13.

[0047] To ensure that the ash supply control commands generated by the ash supply control module can be effectively executed by the ash supply system, corresponding improvements were made to the existing screw pump type mortar conveyor 1, enabling it to have online water addition, adjustable mixing, and adjustable pumping parameters. The following is combined with... Figures 5-6 The improved ash supply system is described.

[0048] I. Addition of water supply device

[0049] A water supply device is added above or on the upper side wall of the silo 11. The water supply device includes a clean water tank 141, a metering pump 142, a water supply pipeline, and an electromagnetic flowmeter 143 and an electromagnetic shut-off valve 144 installed on the water supply pipeline. The clean water tank 141 stores supplementary water, and its volume is selected based on the maximum estimated supplementary water volume within a single construction cycle. The inlet of the metering pump 142 is connected to the clean water tank 141 via a pipeline, and its outlet is connected to the interior of the silo 11 via the water supply pipeline. The outlet end of the water supply pipeline is configured as a spray head 145, installed on the upper inner wall of the silo 11, allowing supplementary water to be injected into the mortar in the silo 11 in a dispersed spray manner, facilitating rapid mixing of the supplementary water and mortar and preventing excessively high water-cement ratios in certain areas. The electromagnetic flowmeter 143 is used to measure the actual water flow rate in the water supply pipeline in real time and feeds the flow signal back to the mortar supply control module to achieve closed-loop precise control of the water supply volume. The metering pump 142 is driven by a variable frequency drive, and its speed is controlled by the water supply adjustment command output by the ash supply control module: when the ash supply control module outputs an instruction to increase the water supply, the speed of the metering pump 142 increases accordingly, and the water flow rate increases; when the ash supply control module outputs an instruction to decrease the water supply, the speed of the metering pump 142 decreases accordingly, and the water flow rate decreases; when there is no water supply instruction, the metering pump 142 is in a stopped state, the electromagnetic shut-off valve 144 is closed, and no water is injected into the silo 11. The electromagnetic shut-off valve 144 is located between the outlet of the metering pump 142 and the spray head 145, and is used to cut off the water supply passage when the metering pump 142 stops, preventing clean water from flowing into the silo 11 by gravity.

[0050] II. Addition of a mixing mechanism

[0051] A stirring mechanism is added inside the silo 11 to replace or supplement the original vibrating motor. The stirring mechanism includes a stirring motor 151, a stirring shaft, and stirring blades 152. The stirring motor 151 is installed at the top of the silo 11 and is driven by a frequency converter. Its output shaft passes through the silo 11 through a sealed bearing assembly and is coaxially connected to the stirring shaft. The stirring shaft extends along the vertical central axis of the silo 11 to near the bottom of the silo 11, and multiple layers of stirring blades 152 are arranged axially at intervals on it. The form of the stirring blades 152 is selected according to the viscosity of the mortar: frame blades or ribbon blades are used. Frame blades are suitable for medium and low viscosity mortars and can achieve overall tumbling of the mortar in the silo 11 at a lower speed to prevent mortar settling and stratification. Ribbon blades are suitable for higher viscosity mortars. Their spiral ribbon structure applies radial shear and axial conveying action to the mortar during rotation, which helps to break the internal structure of the mortar formed by thixotropic recovery or accelerated hydration reaction, so that the mortar is in a fully sheared and dispersed state before entering the pumping device. The speed of the mixing motor 151 is controlled by the mixing speed adjustment command output by the ash supply control module: when the ash supply control module outputs a command to increase the mixing speed, the frequency converter of the mixing motor 151 correspondingly increases the output frequency, the mixing speed increases, and the shear rate and shear action time experienced by the mortar in the silo 11 increase, which helps to reduce the yield stress and apparent viscosity of the mortar; when the ash supply control module outputs a command to decrease the mixing speed, the frequency converter decreases the output frequency, and the mixing speed decreases accordingly. The mixing mechanism and the original vibrating motor can coexist: the vibrating motor continues to play an auxiliary role in preventing mortar from bridging and arching at the conical bottom of the silo 11, while the mixing mechanism mainly undertakes the function of actively shearing and controlling the mortar. The two complement each other in function.

[0052] It should be noted that the installation height of the lowest layer of the mixing blades 152 should be higher than the upper edge of the bottom discharge port of the silo 11 to avoid interference between the mixing blades 152 and the mortar flow channel at the inlet of the pumping device. At the same time, the sealing bearing assembly between the mixing shaft and the top inlet of the silo 11 should adopt a mechanical seal suitable for mortar conditions to prevent mortar from overflowing along the mixing shaft.

[0053] III. Adjustable modification of pumping parameters

[0054] The drive method of screw pump 12 is modified to be adjustable so that the feeding pressure and flow rate can be adjusted online in response to the commands of the mortar supply control module. Specifically, the drive motor of screw pump 12 is changed from the original fixed-speed drive to variable-frequency drive. Since screw pump 12 is a positive displacement pump, its theoretical displacement is proportional to its speed. Therefore, by adjusting the output frequency of the inverter of screw pump 12 drive motor, the speed of screw pump 12 can be directly controlled, thereby adjusting the mortar supply flow rate. When the mortar supply control module outputs a command to increase the feeding pressure, the inverter increases the output frequency, the speed of screw pump 12 increases, the volume of mortar pumped into the mortar supply pipeline 13 per unit time increases, and the pipeline pressure increases accordingly to compensate for the increase in pipeline resistance caused by the increase in mortar yield stress or plastic viscosity. When the mortar supply control module outputs a command to decrease the feeding flow rate, the inverter decreases the output frequency, the speed of screw pump 12 decreases, and the feeding flow rate decreases accordingly.

[0055] If an air pump is connected to the mortar supply pipeline 13 (the air pump's function is to inject compressed air into the mortar supply pipeline 13: firstly, to expand within the mortar supply pipeline 13 to generate auxiliary thrust, enhancing the pumping device's ability to transport high-viscosity, high-resistance mortar and reducing the risk of pipe blockage; secondly, to use high-speed airflow to disperse or atomize the continuously pumped mortar flow), the air pump's supply pressure regulation method can be set to an electronically controlled proportional pressure regulating valve 161. The control signal for the electronically controlled proportional pressure regulating valve 161 is provided by the mortar supply control module, allowing the compressed air pressure injected into the mortar supply pipeline 13 by the air pump to be adjusted online according to the mortar supply control command. When the mortar viscosity increases and the pipeline resistance increases, appropriately increasing the air pump's supply pressure can enhance the auxiliary effect of the gas expansion thrust on mortar transportation and reduce the risk of pipe blockage; when the mortar viscosity is too low and the fluidity is too high, appropriately reducing the air pump's supply pressure can avoid excessive disturbance of the mortar by the gas.

[0056] IV. Installation of Effective Measurement Pipe Section 131

[0057] To achieve online identification of mortar rheological parameters in the mortar supply pipeline 13, a straight effective measurement section 131 is installed in the mortar supply pipeline 13, with a pressure sensor 132 installed at each end of the effective measurement section 131 to collect the pressure difference ΔP between the two ends of the section in real time. A flow stabilization section is set between the effective measurement section 131 and the outlet of the screw pump 12. The length of the flow stabilization section is not less than a preset multiple of the inner diameter D of the effective measurement section 131 (e.g., the length of the flow stabilization section ≥ 10D, where D is the inner diameter of the effective measurement section 131, D = 2R, and R is the inner radius). This ensures that the mortar flow forms a fully developed laminar flow field in a circular pipe before entering the effective measurement section 131, eliminating the interference of pumping pulsation and upstream pipeline bends on the uniformity of the measured flow field, ensuring measurement accuracy, and thus satisfying the flow field condition assumptions for subsequent rheological parameter identification based on the Buckingham-Reiner equation. Furthermore, if an air pump is connected to the ash supply pipeline 13, the effective measuring section 131 should be located upstream of the air pump injection point (i.e., the air pump injection point is located downstream of the effective measuring section 131) to ensure that the flowing medium in the measuring section is pure mortar rather than an air-sand mixture, thus guaranteeing the effectiveness of rheological parameter identification. The output signals of the two pressure sensors are connected to the hardware platform of the intelligent ash supply control system for real-time reading by the mortar rheological parameter identification module of the ash supply pipeline.

[0058] The pressure sensors 132 at both ends of the effective measuring pipe section 131 are thin-film pressure sensors. Their sensitive elements are in direct contact with the mortar, eliminating the need for pressure guiding pipes. This avoids mortar deposition and blockage in the pressure guiding holes or pipes, making it suitable for pressure measurement of high-viscosity media such as mortar containing solid particles.

[0059] V. Standardization of control interfaces for ash supply systems

[0060] In the improved ash supply system, the frequency converters of the metering pump 142, the stirring motor 151, and the screw pump 12 drive motor, the electronically controlled proportional pressure regulating valve 161, and the pressure sensors 132 at both ends of the effective measurement pipe section 131 are all connected to the ash supply control module via an industrial communication bus. The ash supply control module sends ash supply control commands to each actuator via the industrial communication bus and receives operating status parameters from each actuator, including the actual speed and water flow rate of the metering pump 142, the actual speed of the stirring motor 151, the actual speed of the screw pump 12, and the actual output pressure of the electronically controlled proportional pressure regulating valve 161; simultaneously, it receives data collected by the pressure sensors 132 at both ends of the effective measurement pipe section 131 in real time. These operating status parameters, such as the actual speed of the screw pump 12, are used as pumping operating parameters and, together with the differential pressure data collected by the pressure sensors 132, are used by the ash supply pipeline mortar rheological parameter identification module to identify the rheological parameters of the mortar in the ash supply pipeline 13 online. Thus, the improved ash supply system forms a complete two-way communication architecture of command issuance and status feedback, providing a unified hardware foundation for the ash supply control module to achieve coordinated adjustment of water addition, stirring speed, feeding pressure and feeding flow, and for the mortar rheological parameter identification module of the ash supply pipeline to achieve continuous online identification of rheological parameters.

[0061] For the plastered surface quality identification module, the associated hardware in this embodiment is a plastering quality detection device. The plastering quality detection device includes a surface detection sensor mounted on the plastering execution mechanism 2 and moving in tandem with it. This sensor is used to perform real-time detection of the plastered surface and output detection data. The plastered surface quality identification module identifies quality deviations based on the detection data acquired by the surface detection sensor.

[0062] In one specific embodiment, the surface detection sensor is an industrial camera, and the detection data is image data of the plastered surface (e.g., ...). Figure 4(As shown). The working principle of the industrial camera is as follows: the surface morphology of the plastered surface is projected onto an image sensor (CCD or CMOS) through a fixed focal length lens, and the light reflection distribution of the surface is recorded in the form of a pixel grayscale matrix. Because the surface undulations, pits, textures, and other micro-morphological features of the plastered surface cause differences in the distribution of diffuse reflection light intensity, this difference is reflected in the image as changes in local grayscale values. Therefore, the rougher the surface, the more uneven the grayscale distribution of the image and the more complex the texture features. In the specific application scheme of this embodiment, the industrial camera is installed at the bottom of the plastering execution mechanism 2, with the lens facing the area that has been plastered. The optical axis maintains a certain angle with the normal direction of the plastered surface to enhance the shadow contrast of the surface micro-morphology; to reduce ambient light interference, a ring-shaped supplementary light source is provided to ensure the illumination stability of the acquired image. After receiving image data from an industrial camera, the plastered surface quality identification module first preprocesses the image (including noise reduction and grayscale normalization). Then, it extracts texture feature parameters based on the Gray-Level Co-occurrence Matrix (GLCM), including contrast, entropy, correlation, and uniformity. Finally, it calculates a quantitative index characterizing the surface roughness of the plastered surface by combining these texture feature parameters. If this index exceeds a preset allowable range, the plastered surface is identified as having surface roughness deviation. The image preprocessing, GLCM texture feature extraction, and surface roughness quantification methods described above are all existing mature technologies. This embodiment applies them to the surface quality inspection scenario of plastered surfaces.

[0063] In another specific embodiment, the surface detection sensor is a laser profile sensor, and the detection data is surface profile data. The working principle of the laser profile sensor is laser triangulation: the laser emitting unit inside the sensor projects a linear laser beam onto the surface being measured. After the laser beam hits the surface, it undergoes diffuse reflection. The reflected light is converged by the receiving lens onto the internal image sensor to form a light spot. When there are height undulations on the surface being measured, the imaging position of the reflected light spot on the image sensor shifts accordingly. The sensor calculates the height value of each point within the laser beam coverage area relative to the sensor reference plane in real time based on the fixed angle between the emitting and receiving optical axes (triangulation geometry), thereby outputting a complete cross-sectional profile data. The laser profile sensor is also installed at the lower part of the plastering execution mechanism 2. The direction of the laser beam is perpendicular to the movement direction of the plastering execution mechanism 2. The sensor moves continuously with the plastering execution mechanism 2 along the plastering direction, scanning the plastered surface line by line, thereby collecting a continuous cross-sectional profile dataset covering the plastered area. After receiving the aforementioned contour data, the plastered surface quality identification module extracts surface roughness parameters such as the arithmetic mean deviation Ra or the root mean square deviation Rq of the contour within the evaluation length, according to the surface roughness evaluation method. Compared to industrial camera solutions, laser contour sensors can directly output highly quantified data with physical dimensions. The correspondence between the measurement results and the actual surface morphology is more direct, less affected by ambient lighting conditions, and exhibits better robustness in construction environments with significant color differences in plastered surfaces or unstable lighting conditions. If the surface roughness parameters of the plastered surface exceed the preset allowable range, the plastered surface quality identification module identifies it as having surface roughness deviation. The aforementioned laser triangulation method, line-by-line scanning to acquire contour datasets, and surface roughness evaluation method are all existing mature technologies.

[0064] One of the core quality objectives of plastering construction is to obtain a smooth and uniform surface, and surface roughness is a quantitative indicator that directly reflects this objective. The rheological parameters of mortar (such as yield stress and plastic viscosity) determine its spreadability, shape retention, and adhesion to the substrate during the plastering process. When these rheological parameters deviate from the normal range, the mortar is difficult to spread evenly under the action of the plastering actuator 2, ultimately resulting in an abnormal increase in surface roughness. Therefore, surface roughness can intuitively reflect the influence of the mortar's rheological state on the plastering quality, and is the most direct physical quantity characterizing the quality of the plastered surface. Using it as a basis for identifying quality deviations has clear engineering significance.

[0065] The rheological parameter identification module for the mortar supply pipeline identifies the following rheological parameters: yield stress τ, the time rate of change of yield stress τ (dτ / dt), plastic viscosity μ, and the time rate of change of plastic viscosity μ (dμ / dt). These parameters can comprehensively reflect the characteristic drift trend of gypsum-based time-varying fluids.

[0066] The mortar rheological parameter identification module for ash supply pipelines models the mortar as a rheological constitutive model with yield stress, preferably the Bingham plastic fluid model. The constitutive equation of the Bingham plastic fluid model is: when the local shear stress exceeds the yield stress τ, the local shear stress = τ + μ·γ̇, where μ is the plastic viscosity and γ̇ is the shear rate; when the local shear stress is lower than the yield stress τ, the fluid does not flow. The flow behavior of gypsum mortar in pumping pipelines matches the above model well and can be considered as steady-state laminar flow of Bingham fluid within a circular pipe. Based on this, by integrating the velocity distribution of Bingham fluid within the circular pipe, the Buckingham-Reiner equation relating the volumetric flow rate Q to the pressure difference ΔP across the pipeline can be derived.

[0067] The Buckingham-Reiner equation establishes a nonlinear functional relationship between volumetric flow rate Q and pressure difference ΔP: Q = (πR) 4 ΔP) / (8μL)·[1-(4 / 3)(τ / τ_w)+(1 / 3)(τ / τ_w) 4 The equation is given by τ_w = RΔP / (2L), where τ_w is the pipe wall shear stress. Since this equation contains two unknowns, yield stress τ and plastic viscosity μ, and only one set of (Q, ΔP) observations can be provided under a single steady-state condition, it is insufficient to simultaneously determine both unknowns. Therefore, the mortar rheological parameter identification module for the ash supply pipeline periodically applies a preset amplitude speed step disturbance to the pumping device. Under at least two different pumping device speed conditions, it collects the corresponding pressure differences ΔP1 and ΔP2, and the volumetric flow rates Q1 and Q2 converted from the pumping operating parameters. For each condition, a corresponding flow equation is established based on the Buckingham-Reiner equation. The obtained at least two equations are then combined to form an equation set, which is solved online to obtain the yield stress τ and plastic viscosity μ. The selection of the above-mentioned speed step disturbance amplitude Δn should balance the requirements of both identification accuracy and construction disturbance: if Δn is too small, the difference between the (Q, ΔP) data points corresponding to the two working conditions is insufficient, the ill-conditioned nature of the equation system increases, and the solution error is amplified; if Δn is too large, the transient change in material flow rate caused by speed switching will significantly interfere with the uniformity of plastering construction. It is recommended that Δn be taken as 10% to 20% of the current working speed. Within this range, the pressure difference between the two working conditions is usually sufficient to ensure identification accuracy, while the impact of short-term fluctuations in material flow rate on plastering quality is within an acceptable range; the specific value should be determined in combination with equipment characteristics and construction verification results. The mortar rheological parameter identification module of the mortar supply pipeline further calculates the time change rate dτ / dt of yield stress τ and the time change rate dμ / dt of plastic viscosity μ by performing time difference analysis on the identification results at each moment.

[0068] Taking a specific construction moment as an example: A preset step increment Δn is superimposed on the current operating speed n0, causing the pumping device to operate sequentially at two conditions: speed n1=n0 and speed n2=n0+Δn. After the flow in the pipeline reaches steady state under each condition, the corresponding differential pressure observations ΔP1 and ΔP2 are collected. The volumetric flow rates Q1 and Q2 are calculated from the operating speed and the known single-rotation displacement V0 of the pumping device (i.e., Q=n·V0), without the need for additional flow meters. Substituting the two sets of (Q1,ΔP1) and (Q2,ΔP2) into the Buckingham-Reiner equations, two equations with τ and μ as unknowns are obtained. These equations are then combined to form a system, which is solved online using a numerical iteration method (such as Newton's iteration method) to obtain the identified values ​​of τ and μ at that moment. The complete process of switching between two operating conditions, waiting in steady state, acquiring differential pressure, and solving the equations is defined as one identification cycle. The duration of the identification cycle is determined by the waiting time required to switch the speed to steady state and the numerical solution time, typically ranging from 30 to 60 seconds. In practical applications, it can be adjusted appropriately according to the drift rate of the mortar rheological properties and the requirements of construction control response. For the calculation of the time change rate, if the yield stress τ1 is identified at time t1 and the yield stress τ2 is identified at time t2, then the time change rate of the yield stress during this period is dτ / dt≈(τ2-τ1) / (t2-t1). The time change rate of plastic viscosity dμ / dt is calculated in the same way. As the hydration process of gypsum mortar progresses, τ and μ usually show a monotonically increasing trend. The continuous increase of dτ / dt and dμ / dt indicates the accelerated drift of the mortar rheological properties, which can provide a basis for feedforward compensation of subsequent construction parameters.

[0069] The core function of the diagnostic decision module is to generate correlation-based diagnostics and preventative control decisions. This module receives surface quality data from the plastered surface quality identification module and rheological parameter data from the mortar rheological parameter identification module of the mortar supply pipeline. For cases where the quality deviation is a surface roughness deviation, preset correlation rules include: when the surface roughness of the plastered surface exceeds a preset allowable range, if the yield stress τ and / or plastic viscosity μ deviate from their respective preset reference values ​​(drifting out of the normal range), and the absolute values ​​of the time-varying rates of change of yield stress τ (dτ / dt) and / or plastic viscosity μ (dμ / dt) exceed their respective preset thresholds (indicating a significant and continuous change in rheological properties), then the surface roughness deviation is determined to be attributable to a change in mortar rheological properties. This generates a corresponding mortar supply control decision and outputs it to the mortar supply control module. If the rheological parameters do not exhibit the aforementioned deviations or continuous changes, the quality deviation is determined to be caused by factors related to the wall substrate or hardware failures in the plastering system, and mortar supply control is not triggered to avoid misadjustment.

[0070] The surface quality data output by the plastered surface quality identification module and the rheological parameter data output by the mortar rheological parameter identification module of the mortar supply pipeline originate from different acquisition channels, and there is an inherent asynchrony between the two in time: the surface quality data is acquired after the mortar has been troweled by the plastering actuator 2, while the rheological parameter data is identified when the mortar is still being transported in the mortar supply pipeline 13. Therefore, before performing correlation diagnosis, the diagnostic decision module needs to estimate the total time delay Δt of the mortar from the rheological parameter identification position through the mortar supply pipeline 13 to the plastering outlet, and then from troweling to being detected by the surface detection sensor, based on the movement speed of the plastering actuator 2 and the known length of the mortar supply pipeline 13. Based on this, the two sets of data are aligned on the time axis, that is, the surface quality data acquired at time t is matched with the rheological parameter data identified at time t-Δt, to ensure that the two sets of data participating in the correlation diagnosis reflect the state of the same batch of mortar.

[0071] To determine whether the yield stress τ and plastic viscosity μ have drifted out of the normal range, the diagnostic decision module compares the identified values ​​at each time point with their respective preset benchmark values. If the identified values ​​of yield stress τ and plastic viscosity μ exceed the normal range corresponding to their respective preset benchmark values, then the corresponding parameters are determined to have deviated. The aforementioned preset benchmark value range is pre-calibrated based on the normal rheological characteristics range of the gypsum-based mortar material used, and can be adaptively updated by statistically analyzing several sets of identification results during the initial construction stage.

[0072] The preset parameters involved in the aforementioned diagnostic decision-making module, including the preset benchmark value ranges for yield stress τ and plastic viscosity μ, the preset thresholds for dτ / dt and dμ / dt in correlation diagnosis, the preset trend thresholds for dτ / dt and dμ / dt in preventive diagnosis mode, and the preset deviation threshold for the normalized comprehensive deviation index S, are calibrated in detail below. The specific determination of the preset benchmark value ranges [τ_min, τ_max] and [μ_min, μ_max] is carried out in two stages. The first stage is pre-calibration in the laboratory before construction: for the proposed mortar type, mortar samples are prepared according to the actual construction mix proportion. Samples are taken periodically at set time intervals starting from the moment mixing is completed. The yield stress τ and plastic viscosity μ at each moment are measured using a rotational rheometer, and τ-t and μ-t curves are plotted. Simultaneously, the same batch of mortar is identified online through the mortar rheological parameter identification module in the mortar supply pipeline, and the results are compared to complete the system error correction. The statistical distribution range (mean ± 2 standard deviations) of the measured values ​​of τ and μ at various times within the construction time window is taken as the initial value of the preset benchmark normal range. This is then corrected based on the verification results from construction practice, ultimately determining the preset benchmark ranges [τ_min, τ_max] and [μ_min, μ_max]. The second stage is an adaptive update at the initial construction stage: In the initial stage after each construction begins, the diagnostic decision module statistically analyzes the mean and standard deviation of several consecutive identification results. If the statistical mean falls within the pre-calibrated range, the normal range for the current batch is updated with the statistical mean ± 2 standard deviations. If the statistical mean exceeds the pre-calibrated range, the normal range is redefined using the statistical mean as the center and the width of the pre-calibrated range. Simultaneously, an abnormal initial rheological state prompt for the mortar is generated, reminding operators to check the mortar mix ratio or the status of the mortar supply system.

[0073] Based on measured data of lightweight gypsum mortar and desulfurized gypsum mortar, typical values ​​for the preset benchmark range of yield stress τ and plastic viscosity μ are given below. These values ​​are based on pre-calibration experiments conducted by the applicant using a screw pump-type mortar conveyor 1 and a matching mortar supply pipeline 13 (effective measuring section 131 inner diameter D=32mm, effective measuring section 131 length L=500mm), and are for reference only for those skilled in the art. In practical applications, recalibration should be performed considering the specific mortar type, mix proportion, and equipment parameters.

[0074] For lightweight gypsum mortar (water-cement ratio 5:10), referring to the consistency data shown in Table 1, the online identification results of its yield stress τ within the construction time window (consistency not lower than approximately 5.0) are approximately 15–80 Pa, and the plastic viscosity μ is approximately 0.8–4.5 Pa·s. Therefore, the preset reference value range for τ can be set to [15 Pa, 80 Pa], and the preset reference value range for μ can be set to [0.8 Pa·s, 4.5 Pa·s]. Considering that the yield stress of lightweight gypsum mortar itself is relatively low, its anti-sagging ability after application to the wall is weak (corresponding to…). Figure 3 (Defect shown in A) To ensure construction adhesion, τ_min can be appropriately increased to 25Pa. That is, when the τ identification value is lower than 25Pa, the mortar is too thin and a decision to reduce the amount of water added is generated to control the mortar supply.

[0075] For desulfurized gypsum mortar (water-cement ratio 6:10), referring to the consistency data shown in Table 1, the online identification results of its yield stress τ during the normal construction stage (consistency not lower than approximately 8.0) are approximately 10–60 Pa, and its plastic viscosity μ is approximately 0.5–3.0 Pa·s. Accordingly, the preset reference value range for τ can be set as [10 Pa, 60 Pa], and the preset reference value range for μ can be set as [0.5 Pa·s, 3.0 Pa·s]. Note that in the data in Table 1, the desulfurized gypsum mortar exhibits a brief increase in consistency (to 9.6) around 10:33 followed by a rapid decline (dropping to around 9.7 at 10:48 and continuing to decrease). This reflects its strong thixotropy and the high sensitivity of its rheological state to shear history. Therefore, the determination of each preset reference value range for desulfurized gypsum mortar should be combined with the time rate of change condition to avoid misjudging the instantaneous identification fluctuations caused by brief thixotropic disturbances as continuous drift in rheological properties.

[0076] The preset thresholds (for correlation diagnosis) and preset trend thresholds (for preventive diagnosis mode condition one) for the time-varying rate of yield stress τ (dτ / dt) and the time-varying rate of plastic viscosity μ (dμ / dt) are calibrated based on the time difference results of the τ-t and μ-t curves obtained in the above pre-calibration experiment. Specifically, the construction time window is divided into several equal-length time periods, and the average time-varying rates of τ and μ are calculated for each time period. The maximum average time change rate corresponding to the initial stage of the construction time window (the stage where rheological properties are relatively stable) is multiplied by a safety margin coefficient (1.5 to 2.0 is recommended) as the preset threshold for dτ / dt and dμ / dt in the correlation diagnosis. This threshold reflects the upper limit of the time-varying rate of rheological properties during the normal hydration process of mortar. The average time change rate corresponding to the middle stage of the construction time window (the stage of accelerated hydration) is multiplied by a safety margin coefficient (1.2 to 1.5 is recommended) as the preset trend threshold for dτ / dt and dμ / dt in the first condition of the preventive diagnosis mode. This threshold is more sensitive than the correlation diagnosis threshold and aims to achieve early warning.

[0077] Taking lightweight gypsum mortar (water-cement ratio 5:10) as an example, referring to the data in Table 1, the consistency gradually decreased from 7.9 to 6.0 within approximately 100 minutes from the completion of mixing to 11:45. Based on this, the average time change rate of yield stress τ during this stage is estimated to be approximately 0.5–1.0 Pa / min, and the average time change rate of plastic viscosity μ is estimated to be approximately 0.02–0.04 Pa·s / min. From 11:45 to 12:45, the consistency rapidly decreased from 6.0 to 4.8 within approximately 60 minutes, indicating a significant acceleration in hydration, with the corresponding time change rate being approximately 2–3 times that of the previous stage. Therefore, the preset threshold for dτ / dt in the correlation diagnosis of lightweight gypsum mortar can be taken as 2.0 Pa / min, and the preset threshold for dμ / dt can be taken as 0.08 Pa·s / min; in the preventive diagnosis mode condition one, the preset trend threshold for dτ / dt can be taken as 1.5 Pa / min, and the preset trend threshold for dμ / dt can be taken as 0.06 Pa·s / min. For desulfurized gypsum mortar, referring to the data in Table 1, its consistency decreases at a faster rate than that of lightweight gypsum mortar within the construction time window, and its thixotropic fluctuations are more pronounced. It is recommended to appropriately lower the preset trend threshold (i.e., make the threshold more sensitive) based on the above reference values ​​to improve the proactive response capability of preventive diagnosis. In the applicant's practice, a better preventive control effect can be obtained when the preset trend threshold for dτ / dt of desulfurized gypsum mortar is 1.2 Pa / min and the preset trend threshold for dμ / dt is 0.05 Pa·s / min.

[0078] It should be noted that the specific values ​​of the above-mentioned preset parameters are closely related to factors such as mortar type, mix ratio (water-cement ratio), ambient temperature and humidity, mortar inventory in silo 11, and diameter and length of mortar supply pipeline 13. The values ​​may vary significantly under different construction conditions. Those skilled in the art should conduct pre-calibration experiments again based on actual working conditions to determine the parameter combinations applicable to specific projects. In addition, there is a systematic deviation between the yield stress τ and plastic viscosity μ measured by the rotational rheometer in the first stage of the pre-calibration experiment and the τ and μ obtained online by the mortar rheological parameter identification module of the mortar supply pipeline based on the Buckingham-Reiner equation, caused by differences in measurement principle, shear history, and temperature. One of the important purposes of the pre-calibration experiment is to quantify and correct the above-mentioned systematic deviation to ensure that the preset benchmark value range adopted by the diagnostic decision module and the online identification results of the mortar rheological parameter identification module of the mortar supply pipeline are in the same quantitative system, thus ensuring the consistency and effectiveness of the diagnostic judgment.

[0079] For the threshold determination of the rate of change over time, the absolute values ​​of the rate of change of yield stress τ (dτ / dt) and the rate of change of plastic viscosity μ (dμ / dt) reflect the drift rate of rheological properties. If the yield stress τ and / or plastic viscosity μ deviate from their respective preset reference values ​​within their normal range, but the absolute values ​​of the rate of change of yield stress τ (dτ / dt) and plastic viscosity μ (dμ / dt) do not exceed their respective preset thresholds, then the deviation is more likely due to occasional differences between mortar batches rather than significant and continuous dynamic evolution of rheological properties. Therefore, simultaneously satisfying both the condition that the yield stress τ and / or plastic viscosity μ drift out of their respective preset reference values ​​within their normal range and that the absolute values ​​of the rate of change of yield stress τ (dτ / dt) and / or plastic viscosity μ (dμ / dt) exceed their respective preset thresholds is a necessary basis for the diagnostic decision module to attribute surface roughness deviation to changes in mortar rheological properties, thereby generating corresponding mortar supply control decisions and outputting them to the mortar supply control module. If the rheological parameters do not deviate or change continuously as described above, the diagnostic decision module determines that the surface roughness deviation is caused by factors of the wall substrate or hardware failure of the plastering system, and does not trigger the plaster supply control to avoid misadjustment.

[0080] It should be noted that the time-varying drift of mortar rheological properties does not always manifest as a synchronous change in yield stress τ and plastic viscosity μ. In the hydration process of gypsum-based mortar, the evolution of yield stress τ and plastic viscosity μ may differ temporally. For example, plastic viscosity μ may have already deviated from the preset benchmark value, and the absolute value of its time-varying rate dμ / dt may have exceeded the preset threshold, while yield stress τ may not have significantly deviated from its preset benchmark value. If the diagnostic condition is set to require both yield stress τ and plastic viscosity μ to simultaneously meet the deviation condition, the diagnostic decision module will not be able to trigger the mortar supply control decision in a timely manner if only one parameter experiences a significant drift, leading to missed detections. Therefore, the aforementioned preset association rule adopts an "AND / OR" relationship. That is, as long as at least one of the yield stress τ and plastic viscosity μ deviates from the normal range of its preset benchmark value, and the absolute value of at least one of the time-varying rates dτ / dt of yield stress τ and dμ / dt of plastic viscosity μ exceeds its preset threshold, the judgment condition is met. This ensures the sensitivity of the diagnostic decision module to changes in mortar rheological properties and avoids missed detections.

[0081] Furthermore, to mitigate the risk of gypsum mortar with a rapid hydration rate thickening or even pipe blockage, the diagnostic decision module is also configured with a preventative diagnostic mode: When the surface quality identification module has not yet detected any quality deviations (the surface inspection results are still acceptable), the diagnostic decision module calculates the drift trend of rheological parameters in real time. When one of the following conditions is met, a preventative mortar supply control decision is generated, directly outputting instructions to the mortar supply system through the mortar supply control module: Condition 1: The absolute values ​​of the time-varying rate of yield stress τ (dτ / dt) and / or the time-varying rate of plastic viscosity μ (dμ / dt) continuously exceed their respective preset trend thresholds for a preset time (indicating a rapid drift in the mortar's rheological properties, with a very high risk of quality defects); Condition 2: The normalized comprehensive deviation index S continuously exceeds the preset deviation threshold for a preset time, where the normalized comprehensive deviation index S = (dτ / dt / Δτ_ref). 2 +(dμ / dt / Δμ_ref) 2 Where Δτ_ref is a reference value used to normalize the yield stress-time change rate, and Δμ_ref is a reference value used to normalize the plastic viscosity-time change rate. Using the normalized comprehensive deviation index can avoid single-item misadjustments caused by inconsistent parameter dimensions, and more comprehensively reflect the overall deviation trend of mortar rheological properties.

[0082] The core difference between preventative diagnosis and correlation diagnosis lies in the timing of triggering: correlation diagnosis is based on the detection of quality deviations by the plastered surface quality condition identification module, which is a post-event attribution; while the preventative diagnosis mode, even before the plastered surface quality condition identification module has identified quality deviations, only relies on the rheological parameter data output by the mortar rheological parameter identification module of the mortar supply pipeline to analyze the drift trend of rheological parameters in real time. Before the quality defects actually appear, preventative mortar supply control decisions are generated in advance and instructions are output to the mortar supply system through the mortar supply control module, thereby curbing the risk of gypsum mortar thickening or even pipe blockage at the bud stage.

[0083] For condition one, when determining whether the absolute values ​​of the time-varying rate of yield stress τ (dτ / dt) and / or the time-varying rate of plastic viscosity μ (dμ / dt) continuously exceed their respective preset trend thresholds, the requirement of a time window that continuously reaches the preset time is introduced. This is to eliminate the transient over-threshold phenomenon caused by occasional measurement noise during the rheological parameter identification process, and to ensure that preventive mortar supply control decisions are generated only when the rheological properties of the mortar undergo a real and continuous sharp drift, thus avoiding misadjustment.

[0084] For condition two, the normalized comprehensive deviation index S is calculated by normalizing the time-varying rates of yield stress τ (dτ / dt) and plastic viscosity μ (dμ / dt) by the reference values ​​Δτ_ref and Δμ_ref respectively, and then summing the squares. This eliminates the interference of the inconsistent dimensions of the two parameters on the comprehensive evaluation results. For example, if the absolute value of the time-varying rate of yield stress τ (dτ / dt) has not yet exceeded its preset trend threshold individually, but both the time-varying rates of yield stress τ (dτ / dt) and plastic viscosity μ (dμ / dt) show a moderate and continuous increase, then the combined effect of the two may cause the normalized comprehensive deviation index S to exceed the preset deviation threshold, thereby triggering a preventative ash supply control decision; this situation would be overlooked in the single-item judgment of condition one. Condition 1 and Condition 2 complement each other. Condition 1 focuses on capturing the abrupt shift of the time-varying rate of yield stress τ (dτ / dt) or the time-varying rate of plastic viscosity μ (dμ / dt), while Condition 2 focuses on capturing the combined trend of the synergistic shift of yield stress τ and plastic viscosity μ. Together, they enhance the preventive diagnostic model's comprehensive ability to perceive the risk of deterioration in mortar rheological properties.

[0085] For the normalized reference values ​​Δτ_ref and Δμ_ref in the normalized comprehensive deviation index S, it is recommended to take the preset trend thresholds of dτ / dt and dμ / dt respectively in the first condition of the preventive diagnostic mode mentioned above. That is, let Δτ_ref be equal to the preset trend threshold of dτ / dt and Δμ_ref be equal to the preset trend threshold of dμ / dt. Using this assignment method, when the absolute value of either dτ / dt or dμ / dt is exactly equal to its corresponding preset trend threshold, the corresponding normalized component is exactly 1. The geometric meaning of the normalized comprehensive deviation index S is: the sum of the squares of the two normalized components measures the comprehensive drift intensity of the time change rate of the two rheological parameters. S=1 corresponds to the case where only one parameter exactly reaches its preset trend threshold, and S=2 corresponds to the case where both parameters exactly reach their respective preset trend thresholds.

[0086] A typical way to set the preset deviation threshold is as follows: when the time change rate of yield stress τ dτ / dt and the time change rate of plastic viscosity μ dμ / dt reach about 71% of their respective preset trend thresholds (i.e., each normalized component is about 0.71), the combined effect of the two corresponds to S≈(0.71). 2 +(0.71) 2The deviation value is approximately 1.01, exceeding the preset deviation threshold of 1.0, thus triggering a preventative mortar supply control decision. However, when any single parameter reaches only 71% of its preset trend threshold, the corresponding value is approximately 0.50, which is below the threshold and will not trigger independently, demonstrating the ability of Condition Two to capture the coordinated drift of the two parameters. Therefore, the preset deviation threshold can be set to 1.0, meaning that a preventative mortar supply control decision is triggered when the normalized comprehensive deviation index S continuously exceeds 1.0. The preset time (i.e., the duration required for S to continuously exceed the preset deviation threshold in Condition Two) is recommended to be the duration corresponding to 2-3 consecutive identification cycles to eliminate transient over-threshold phenomena caused by occasional measurement noise, ensuring that a preventative mortar supply control decision is only generated when there is a real and continuous comprehensive drift in the mortar rheological properties.

[0087] For the ash supply control module, based on the ash supply control decision generated by the diagnostic decision module (which indicates the drift direction of the rheological parameters: too thin, too thick, or too fast thickening rate), it collaboratively generates ash supply control instructions according to the following strategy:

[0088] When the time-varying rate of change of yield stress τ (dτ / dt) is diagnosed as positive and exceeds the preset threshold (the mortar thickens rapidly due to intense hydration), instructions to increase the water addition and increase the stirring speed are generated. This utilizes the combined effects of water dilution and stirring shear to break the thixotropic recovery or early setting structure. Simultaneously, instructions to increase the feed pressure are generated (increasing the screw pump speed or adjusting the air pump supply pressure) to compensate for the decrease in feed flow caused by increased pipeline resistance. Figure 3 The suppression of construction failure risk shown in B;

[0089] When the plastic viscosity μ is higher than the upper limit of the preset benchmark value but the time change rate dτ / dt of the yield stress τ does not exceed the preset threshold (the viscosity is high but the rate of change of rheological properties is still within the controllable range), an instruction to increase the amount of water added is generated and an instruction to increase the feeding pressure is generated at the same time to reduce the mortar viscosity and maintain the normal feeding flow rate.

[0090] When the yield stress τ and / or plastic viscosity μ are lower than their respective preset lower limits (the mortar is too thin, posing a risk of thixotropic sagging), the corresponding... Figure 3 (Defect shown in A) generates instructions to reduce the amount of water added and / or reduce the material flow rate. By reducing the replenishment of dilution medium and appropriately extending the residence time of mortar in silo 11, the recovery of the thixotropic structure of the mortar is promoted, so that the yield stress and plastic viscosity gradually return to the range suitable for construction.

[0091] After generating preventative mortar supply control decisions, the mortar supply control module generates feedforward mortar supply control commands based on the intensity of the rheological parameter drift trend: it generates commands to appropriately increase the amount of water added and to increase the stirring speed to pre-compensate for the deterioration of mortar rheological properties caused by the accelerated hydration process. At the same time, it generates commands to appropriately increase the supply pressure (increase the screw pump speed or increase the air pump supply pressure) to prevent insufficient supply flow due to increased pipeline resistance. The adjustment range of the above mortar supply control commands is determined proportionally based on the absolute values ​​of the normalized comprehensive deviation index S or the time change rate of yield stress τ dτ / dt and the time change rate of plastic viscosity μ dμ / dt, so as to achieve gradual feedforward compensation for the drift of mortar rheological properties and avoid reverse deviation of mortar rheological properties due to over-adjustment.

[0092] The foregoing has described the relevant content of the present invention. Those skilled in the art will be able to implement the present invention based on these descriptions. All other embodiments obtained by those skilled in the art based on the foregoing content of this specification without inventive effort should fall within the scope of the present invention.

Claims

1. An intelligent plastering quality feedback-based mortar supply control system, characterized in that: include: The plastered surface quality identification module is used to identify whether there is a quality deviation in the plastered surface based on the detection data obtained by the plastering quality detection device in real time detection of the plastered surface. The mortar rheological parameter identification module for mortar supply pipeline is used to identify the rheological parameters of the mortar in the mortar supply pipeline online during the process of conveying mortar from the mortar supply system to the plastering actuator through the mortar supply pipeline, based on the detection signals collected by the pressure sensors at both ends of the effective measuring pipe section in the mortar supply pipeline and the pumping operation parameters of the mortar supply system. The rheological parameters include yield stress τ, plastic viscosity μ, the time-dependent rate of change of yield stress τ dτ / dt, and the time-dependent rate of change of plastic viscosity μ dμ / dt. The mortar rheological parameter identification module of the ash supply pipeline models the mortar as a Bingham plastic fluid model with yield stress, and takes the complete process of one dual-condition speed switching, steady-state waiting, pressure difference acquisition and equation solution as an identification cycle. Within each identification cycle, the mortar rheological parameter identification module of the mortar supply pipeline applies a preset amplitude speed step disturbance to the pumping device of the mortar supply system, causing the pumping device to operate sequentially at at least two different pumping device speed conditions. Under each pumping device speed condition, after the mortar flow in the effective measurement section reaches a steady state, the corresponding pressure difference ΔP1, ΔP2 and the volumetric flow rates Q1, Q2 converted from the pumping operation parameters are collected respectively. For each condition, a corresponding flow equation is established based on the Buckingham-Reiner equation. The obtained at least two equations are combined to form an equation system, and the yield stress τ and plastic viscosity μ corresponding to the identification cycle are solved online. By performing time difference on the yield stress τ and plastic viscosity μ obtained in adjacent identification cycles, the time change rate dτ / dt of the yield stress τ and / or the time change rate dμ / dt of the plastic viscosity μ are obtained. The diagnostic decision module is used to determine whether the quality deviation is attributable to the change in the rheological properties of the mortar when the quality deviation is identified by the quality condition identification module of the plastered surface, based on the preset correlation rule between the quality deviation and the rheological parameters, and to generate a corresponding mortar supply control decision when it is determined that the quality deviation is attributable to the change in the rheological properties of the mortar. The mortar supply control module is used to generate mortar supply control instructions based on the mortar supply control decision and output them to the mortar supply system to adjust the rheological properties of the mortar in the mortar supply pipeline.

2. The intelligent plastering quality feedback-based plastering supply control system as described in claim 1, characterized in that: The mortar rheological parameter identification module of the ash supply pipeline obtains the yield stress τ and plastic viscosity μ online by solving the laminar flow dynamic equation of the circular pipe corresponding to the Bingham plastic fluid model based on the pressure difference ΔP measured by the pressure sensors at both ends of the effective measurement pipe section, the mortar volume flow rate Q in the pipe converted from the pumping operation parameters, and the pipeline geometric parameters of the effective measurement pipe section.

3. The intelligent mortar supply control system based on plastering quality feedback as described in claim 2, characterized in that: The online solution establishes the relationship between volumetric flow rate Q and pressure difference ΔP based on the Buckingham-Reiner equation: Q=(πR) 4 ΔP) / (8μL)·[1-(4 / 3)(τ / τ_w)+(1 / 3)(τ / τ_w) 4 ], where R is the inner radius of the effective measuring pipe section, L is the length of the effective measuring pipe section, and τ_w=RΔP / (2L) is the shear stress of the pipe wall; the mortar rheological parameter identification module of the ash supply pipeline establishes corresponding flow equations for the at least two different pumping device speed conditions, and solves the at least two flow equations simultaneously to obtain the yield stress τ and plastic viscosity μ corresponding to the identification period.

4. The intelligent mortar supply control system based on plastering quality feedback as described in claim 1, characterized in that: The quality deviation includes the surface roughness deviation of the plastered surface; the preset association rule includes: when the surface roughness of the plastered surface exceeds the preset allowable range, if the yield stress τ and / or the plastic viscosity μ deviate from their respective preset reference values, and the absolute values ​​of the time change rate dτ / dt of the yield stress τ and / or the time change rate dμ / dt of the plastic viscosity μ exceed their respective preset thresholds, then the quality deviation is determined to be due to the change in the rheological properties of the mortar.

5. The intelligent plastering quality feedback-based plastering supply control system as described in claim 1, characterized in that: The diagnostic decision module is configured to generate a preventative mortar supply control decision and output it to the mortar supply control module when, in the absence of a quality deviation identified by the plastered surface quality condition identification module, one of the following conditions is met: Condition 1: The absolute values ​​of the time-varying rate of yield stress τ (dτ / dt) and / or the time-varying rate of plastic viscosity μ (dμ / dt) continuously exceed their respective preset trend thresholds for a preset time; Condition 2: The normalized comprehensive deviation index S continuously exceeds a preset deviation threshold for a preset time, wherein the normalized comprehensive deviation index S = (dτ / dt / Δτ_ref) 2 +(dμ / dt / Δμ_ref) 2 Where Δτ_ref is a reference value used to normalize the yield stress over time, and Δμ_ref is a reference value used to normalize the plastic viscosity over time.

6. The intelligent plastering quality feedback-based plastering control system as described in claim 1, characterized in that: The ash supply control command includes at least one of the following: a command to adjust the amount of water added to the ash supply system; a command to adjust the stirring speed of the stirring mechanism in the ash supply system; and a command to adjust the feeding pressure and / or feeding flow rate of the ash supply system.

7. The intelligent plastering quality feedback-based plastering control system as described in claim 6, characterized in that: The ash supply control module generates ash supply control instructions according to the following strategy based on the deviation direction of the rheological parameters indicated in the ash supply control decision: when the time change rate of the yield stress τ, dτ / dt, is positive and exceeds a preset threshold, an instruction to increase the water addition and an instruction to increase the stirring speed are generated, along with an instruction to increase the supply pressure to compensate for the increase in pipeline resistance; when the plastic viscosity μ is higher than the upper limit of the preset benchmark value but the time change rate of the yield stress τ, dτ / dt, does not exceed the preset threshold, an instruction to increase the water addition and an instruction to increase the supply pressure are generated; when the yield stress τ and / or the plastic viscosity μ are lower than their respective lower limits of the preset benchmark values, an instruction to decrease the water addition and / or an instruction to reduce the supply flow rate are generated.

8. The intelligent mortar supply control system based on plastering quality feedback as described in claim 1, characterized in that: The plastering quality detection device includes a surface detection sensor installed on the plastering execution mechanism and moving in conjunction with the plastering execution mechanism; the plastered surface quality condition identification module identifies the quality deviation based on the detection data obtained by the surface detection sensor.

9. The intelligent mortar supply control system based on plastering quality feedback as described in claim 8, characterized in that: The surface detection sensor is an industrial camera, the detection data is image data of the plastered surface, and the plastered surface quality condition recognition module calculates the surface roughness of the plastered surface by performing image texture analysis on the image data. Alternatively, the surface detection sensor may be a laser profile sensor, the detection data may be surface profile data, and the plastered surface quality identification module may calculate the surface roughness based on the surface profile data.

10. The intelligent plastering quality feedback-based plastering control system as described in claim 1, characterized in that: The effective measuring pipe section is a straight pipe section in the ash supply pipeline; a flow stabilizing section is provided between the effective measuring pipe section and the outlet of the ash supply system, and the length of the flow stabilizing section is not less than a preset multiple of the inner diameter of the effective measuring pipe section.

Images