An assembled component sits light weight printing robot and construction method

Abstract

The application provides a lightweight printing robot for assembling component sitting mortar and a construction method; the lightweight printing robot comprises a mobile chassis and a positioning device, the top of the mobile chassis is provided with an electric control system and a mechanical arm, a teach pendant is communicatively connected to the electric control system, and a printing extrusion unit is arranged at the tail end of the mechanical arm; wherein the teach pendant is used for planning a printing path and sending path instructions to the electric control system; the electric control system is used for receiving and processing printing path information and feedback signals of the positioning device, and performing closed-loop control on the mobile chassis, the mechanical arm and the printing extrusion unit, so that the sitting mortar strips extruded by the printing extrusion unit are accurately deposited on a preset track; in the application, the mobile chassis can drive the robot to move flexibly on the construction site, adapt to complex working conditions, and realize high-precision deposition of the sitting mortar through closed-loop control of the mechanical arm and the printing extrusion unit, thereby improving construction efficiency and ensuring construction quality.

Description

Technical Field

[0001] This invention belongs to the field of intelligent building construction equipment, specifically relating to a lightweight printing robot for grouting prefabricated components and a construction method thereof. Background Technology

[0002] Prefabricated buildings have been widely used in modern construction due to their advantages such as fast construction speed, controllable quality, and environmental friendliness. In the on-site construction of prefabricated buildings, grouting is a crucial step. It involves laying a smooth layer of cement mortar with a specific thickness and strength on the supporting surface of the prefabricated components before installation. The main functions of the grouting layer are to level the base layer, transfer and evenly distribute the load, seal joints, and provide necessary adhesion.

[0003] Currently, the smoothness, thickness uniformity, and density of the grout layer highly depend on the experience and skill of the tile setter. Manual grouting makes it difficult to guarantee strict levelness, easily leading to elevation errors or uneven stress after precast component installation. Furthermore, inconsistencies in the cross-sectional shape and continuity of the grout strips can affect their sealing and load-bearing performance. Additionally, grouting construction requires workers to work in bent-over or squatting positions for extended periods, leading to worker fatigue, slow construction speed, and difficulty meeting the demands of large-scale, rapid prefabricated construction. Moreover, manual grouting makes it difficult to precisely control material usage, easily resulting in waste.

[0004] To avoid the aforementioned technical problems, some construction sites have attempted to introduce automated equipment into building construction. For example, large gantry 3D printers are used for ground leveling or wall printing. However, such equipment is bulky, inconvenient to deploy, costly to construct, and cannot move and operate flexibly in space-constrained sites. Other teach-and-playback robotic arms are used for material laying at fixed workstations, offering limited flexibility.

[0005] Therefore, there is an urgent need to design a prefabricated component grouting construction equipment that can move flexibly, adapt to complex working conditions, improve construction efficiency, and ensure construction quality to solve the current technical problems. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a lightweight printing robot and construction method for prefabricated component grouting, which is flexible, adaptable to complex working conditions, improves construction efficiency, and ensures construction quality.

[0007] The technical solution of the present invention is: a lightweight printing robot for prefabricated component slurry placement, including a mobile chassis and a positioning device, wherein an electronic control system and a robotic arm are provided on the top of the mobile chassis, a teach pendant is connected to the electronic control system, and a printing extrusion unit is provided at the end of the robotic arm; The teach pendant is used to plan the printing path and send the path instructions to the electronic control system. The electronic control system is used to receive and process the printing path information and the feedback signal from the positioning device, and to perform closed-loop control on the mobile chassis, robotic arm and printing extrusion unit, so that the slurry strip extruded by the printing extrusion unit is accurately deposited on the preset trajectory.

[0008] Furthermore, the electronic control system is configured to synchronously adjust the movement speed of the robotic arm and the extrusion rate of the printing extrusion unit according to the printing path information, so as to control the line shape and cross-sectional shape of the printing.

[0009] Furthermore, the positioning device is a laser positioning device, which is mounted on the base of the mobile chassis or the robotic arm, and is used to project a positioning light spot onto the construction area. The electronic control system identifies the positioning light spot through the image acquisition unit to establish a construction coordinate system and determine the printing start origin.

[0010] Furthermore, the electronic control system also includes a task management module, which stores at least one printing task, the printing task including the printing path information and related process parameters; The task management module has an interruption point recording and recovery function, which can save the spatial location and equipment status information of the interruption point when the operation is interrupted, and control the operation to resume from the interruption point or the associated resume point based on the saved spatial location and equipment status information of the interruption point.

[0011] Furthermore, the end of the robotic arm is provided with a base surface three-dimensional scanning unit; The base surface 3D scanning unit is used to acquire 3D point cloud data of the construction area; The electrical control system is configured to identify the elevation difference of the construction base surface based on the three-dimensional point cloud data of the construction area, and dynamically adjust the height offset of the printing path of the robotic arm in the Z-axis direction according to the preset design thickness of the grout layer and the horizontal requirements of the upper surface, so that the top surface of the printed grout layer is horizontal and the thickness at each point is not lower than the design value.

[0012] Furthermore, the lightweight printing robot for prefabricated component grouting also includes a material condition monitoring unit; The material condition monitoring unit is located inside the printing extrusion unit and is used to monitor the rheological parameters and / or temperature of the slurry material. The electronic control system is configured to estimate the remaining printable time of the current batch of slurry material based on the feedback data from the material state monitoring unit and the built-in material hydration kinetic model, and to dynamically adjust the printing strategy based on this remaining printable time. The printing strategy includes any one of the following: adjusting the printing speed, planning the transition area between new and old materials, or sending a warning signal to the teach pendant.

[0013] A lightweight printing construction method for prefabricated component grouting, employing a printing robot as described in any of the preceding methods, includes the following steps: Site positioning: Control the mobile chassis to move to the construction area, and use the positioning device to establish the current construction coordinate system and determine the printing origin; Material preparation: Prepare the slurry using a slurry mixer and then convey the slurry to the printing extrusion unit; Printing initialization: Control the robotic arm to move the printing extrusion unit to the printing origin; Automatic printing: The printing extrusion unit is controlled to start extruding the slurry, and the robotic arm is controlled to move along a preset printing path to deposit the slurry onto the construction substrate. Interruption and Resumption: If an interruption occurs during printing, the interruption status information is recorded; when printing resumes, based on the interruption status information, the printing robot is controlled to continue the remaining printing path from the resumption point.

[0014] Furthermore, establishing the current construction coordinate system using the positioning device includes the following steps: At least two non-collinear reference marks are projected onto the construction base surface by the positioning device. The image acquisition unit obtains the image position of the reference marks, and the absolute or relative coordinates of the construction coordinate system and the printing origin are determined by the electronic control system.

[0015] Furthermore, the method for determining the starting point of the continued construction includes the following steps: If the interruption duration is less than the first threshold, then the start point of the reconstruction is the spatial location of the recorded interruption point; If the interruption duration reaches or exceeds the first threshold, the start point for resuming printing is the position at which the interruption point is traced back a preset distance along the printed path, so that when printing resumes, the newly printed slurry and the already deposited slurry partially overlap to enhance the joint strength.

[0016] Furthermore, the preset print path is obtained through one of the following methods: Generated from building information model data after slicing; This is generated by teaching the robotic arm online using the teach pendant.

[0017] The beneficial effects of this invention are: (1) In this invention, the mobile chassis can drive the robot to move flexibly on the construction site and adapt to complex working conditions. Through closed-loop control of the robotic arm and the printing extrusion unit, high-precision deposition of the slurry can be achieved, improving construction efficiency and ensuring construction quality. (2) The electronic control system accurately and stably controls the geometric shape of the slurry strip, such as the line width, line height, and cross-sectional shape, avoiding material accumulation, strip breakage, or uneven shape caused by the mismatch between printing speed and extrusion amount, thereby ensuring the uniformity, density, and design thickness of the slurry layer. (3) This robot can automatically identify and compensate for unevenness of the base surface and decide the printing height of each point, ultimately ensuring that no matter what the base surface conditions are, the printed grout layer has a horizontal top surface and meets the required structural thickness. This provides a precise and reliable flat base for the installation of the upper prefabricated components, fundamentally improving the construction quality and precision of prefabricated buildings. (4) In the event of material interruption, the electronic control system can choose to directly resume or backtrack and overlap according to the interruption duration, optimize the mechanical properties of the joint between the new and old materials, and avoid the weak links of the traditional manual joint. (5) By using built-in sensors to monitor material viscosity and temperature in real time, and using hydration kinetics model to predict printable time, the printing speed can be dynamically adjusted or an early warning can be given. This enables the robot to monitor the material state, avoid printing failures caused by changes in material properties, and improve process reliability. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the lightweight printing robot for mounting prefabricated components in this invention.

[0019] Figure 2 This is a flowchart of the lightweight printing construction method for prefabricated components using grouting in this invention.

[0020] Figure 3 This is a schematic diagram of the paddle mixer used in the construction method of the present invention. Detailed Implementation

[0021] Various exemplary embodiments of the invention will now be described in detail with reference to the accompanying drawings. The descriptions of the exemplary embodiments are merely illustrative and are in no way intended to limit the invention or its application or use. The invention can be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the invention thorough and complete, and to fully express the scope of the invention to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, the composition of materials, numerical expressions, and values ​​set forth in these embodiments should be interpreted as merely exemplary and not as limiting.

[0022] The terms "first," "second," and similar words used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Words such as "including" or "comprising" mean that the element preceding the word encompasses the element listed after it, without excluding the possibility of encompassing other elements. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0023] like Figure 1 As shown, a lightweight printing robot for prefabricated component slurry application is disclosed, including a mobile chassis 1 and a positioning device. An electronic control system 2 and a robotic arm 3 are installed on the top of the mobile chassis 1. A teach pendant 4 is connected to the electronic control system 2 for communication. A printing extrusion unit 5 is installed at the end of the robotic arm 3. The teach pendant 4 is used to plan the printing path and send the path instructions to the electronic control system 2. The electronic control system 2 is used to receive and process the printing path information and the feedback signal from the positioning device, and to perform closed-loop control of the mobile chassis 1, the robotic arm 3 and the printing extrusion unit 5, so that the slurry strip extruded by the printing extrusion unit 5 is accurately deposited on the preset trajectory.

[0024] In this embodiment, the teach pendant 4 serves as the human-computer interaction and high-order planning interface, while the electronic control system 2 receives and processes path instructions and positioning feedback data to achieve multi-axis motion control of components such as the mobile chassis 1, robotic arm 3, and printing extrusion unit 5. The mobile chassis 1 enables the robot to move flexibly on the construction site, adapting to complex working conditions. Closed-loop control of the robotic arm 3 and printing extrusion unit 5 achieves high-precision slurry deposition, improving construction efficiency and ensuring construction quality.

[0025] In some embodiments, the electronic control system 2 is configured to synchronously adjust the movement speed of the robotic arm 3 and the extrusion rate of the printing extrusion unit 5 according to the printing path information, so as to control the line shape and cross-sectional shape of the printing.

[0026] Specifically, the electronic control system 2 integrates a motion planning module and an extrusion control module. The motion planning module analyzes the geometric features of the path, including the length of straight segments, the curvature of curves, and the angle of corners. Based on preset printing line width and layer height process parameters, it calculates the theoretical deposition cross-sectional area. According to the requirements of construction efficiency and material properties, it plans a reasonable printing speed curve for the entire path or segments, ensuring high-speed operation in straight segments and automatic speed reduction in corners or fine areas to ensure contour accuracy. The extrusion control module calculates the required material volumetric flow rate in real time based on the product of the cross-sectional area and the printing speed, and combines it with the printing extrusion unit. The mechanical parameters of the screw or piston in unit 5 are used to convert the volumetric flow rate into corresponding motor speed or stroke speed commands. During printing, the electronic control system 2 sends the planned motion speed commands to the servo drives of each joint of the robotic arm 3, and simultaneously sends the calculated extrusion rate commands to the motor drive of the printing extrusion unit 5. The two are synchronized at the millisecond level through a unified system clock or motion controller, ensuring that the material supply and consumption match at any time and any path point. For sections with special cross-sectional shape requirements, the electronic control system 2 can achieve this by superimposing specific speed and extrusion rate modulation curves on the basic algorithm. As an example, in the initial printing section, a ramp function that gradually increases the extrusion rate to a stable value can be used to avoid initial material accumulation.

[0027] Through the above-mentioned synchronous control, it can be ensured that the printed slurry strip has a uniform width and height, and the cross-sectional shape is close to the designed rectangle or trapezoid. This effectively avoids defects such as broken strips and cavities caused by insufficient extrusion or material accumulation and wrinkles caused by excessive extrusion, thereby ensuring the overall density, flatness and thickness uniformity of the slurry layer.

[0028] In some embodiments, the positioning device is a laser positioning device, which is mounted on the base of a mobile chassis or robotic arm and is used to project a positioning spot onto the construction area; the electronic control system identifies the positioning spot through the image acquisition unit to establish a construction coordinate system and determine the printing start origin.

[0029] Specifically, the image acquisition unit is a component of the electrical control system 2, which provides visual feedback to the electrical control system. The image acquisition unit can be an industrial camera equipped with an industrial lens, which needs to be used in conjunction with a supplementary light in construction environments with insufficient light. More specifically, the industrial camera is a global shutter CMOS camera.

[0030] Before operation, the equation of the laser beam in the coordinate system of the image acquisition unit and the fixed transformation relationship between the image acquisition unit and the robot base coordinate system are determined through pre-calibration. During operation, the laser positioning device projects at least two non-collinear reference spots onto the construction surface, and the image acquisition unit acquires images containing these spots. The electronic control system 2 extracts the pixel coordinates of the spot centers through image processing and, combined with calibration parameters and known construction surface height information, calculates the three-dimensional spatial coordinates of each spot in the robot coordinate system. Subsequently, a construction coordinate system is virtually defined based on these spots, and the transformation relationship between this coordinate system and the robot coordinate system is calculated. Finally, based on the printing path preset in the construction coordinate system, control commands in the robot coordinate system are generated in real time through the transformation relationship to drive the robotic arm to move. This process forms a closed loop, and even if the robot undergoes slight displacement, real-time position correction can be achieved by re-identifying the spots fixed to the base surface, thereby ensuring printing accuracy.

[0031] As another implementation, the laser positioning device is mounted on the mobile chassis 1, while the image acquisition unit can be mounted on the end of the robotic arm and move together with the printing extrusion unit 5. This arrangement helps to obtain an observation field of view without local obstruction.

[0032] As a preferred embodiment, one or two adjustable support columns are added to the top of the mobile chassis 1. The laser positioning device is installed on the top of the column, and the image acquisition unit is installed on another independent column or at different heights of the same column, with its optical axis facing the construction area. This arrangement ensures the stability of the positioning system reference and the global field of view.

[0033] Regardless of the installation method, a high-precision joint calibration between the laser positioning device, the image acquisition unit, and the robot coordinate system must be completed during system initialization to determine their fixed spatial transformation relationship and lay the foundation for subsequent real-time coordinate calculation.

[0034] In some embodiments, the electronic control system 2 further includes a task management module, which stores at least one printing task. The printing task includes printing path information and related process parameters. The task management module has an interruption point recording and recovery function, which can save the spatial location and equipment status information of the interruption point when the operation is interrupted, and control the operation to resume from the interruption point or the associated printing point based on the saved spatial location and equipment status information of the interruption point.

[0035] The task management module can store and manage multiple printing tasks. Each task is an independent data package, which not only contains the printing path consisting of a series of spatial coordinate points, but also stores all the process parameters required to execute the task, including but not limited to: printing speed, extrusion rate, layer height, line width, and batch information of the material used.

[0036] When the operation is interrupted due to material depletion, equipment failure, or external emergency, the task management module immediately triggers the interruption handling routine. This routine does not merely record the program execution breakpoint, but rather saves the overall operating state of the robot system at the moment of interruption. The overall operating state of the robot system includes the robot's spatial pose information, equipment operating status, and task progress information. The spatial pose information refers to the global coordinates (X, Y) and orientation θ of the mobile chassis 1; the real-time angles of all joints of the robotic arm 3; the spatial coordinates (X, Y, Z) and orientation of the end of the printing extrusion unit 5; the equipment operating status refers to the motor speed of the printing extrusion unit, the pressure or remaining material in the cylinder, and the enabled status of each driver; the task progress information refers to the identifier of the currently executing printing path segment, the percentage of the path completed, and the next path point to be executed.

[0037] Upon receiving the instruction to resume the operation, the task management module first executes a resumption decision process. The electronic control system 2 reads the saved interruption status and verifies the consistency between the current actual equipment status and the saved status. If there is a discrepancy, the electronic control system 2 will issue an alarm and guide the operator to manually reset or confirm. If the interruption time is short and the equipment status remains unchanged, the robotic arm and chassis are precisely reset to the recorded spatial position, and the printing extrusion unit starts directly from the recorded rotation speed, seamlessly continuing printing from the interruption point. If the interruption time is long, it is determined that the material interface has initially solidified, and direct reconnection may lead to poor bonding. In this case, the module calculates a re-printing point on the completed printing path based on the preset backtracking distance. The electronic control system 2 controls the equipment to move to this re-printing point and begins printing with a specific restart process, creating an overlap area between the new and old materials to ensure joint strength before continuing to complete the remaining path.

[0038] All the aforementioned tasks and their interruption statuses are persistently stored as files in non-volatile memory, ensuring that task progress is not lost even in the event of a complete system power failure. This task management module design enables the printing robot to handle various unforeseen circumstances on the construction site, significantly improving operational reliability. Ensuring the preservation of construction progress and preventing the entire task from being lost due to interruptions effectively improves construction efficiency and equipment utilization, serving as a key supporting function for achieving automated continuous construction.

[0039] In some embodiments, the end of the robotic arm 3 is provided with a base surface three-dimensional scanning unit; the base surface three-dimensional scanning unit is used to acquire three-dimensional point cloud data of the construction area; the electronic control system 2 is configured to identify the elevation difference of the construction base surface based on the three-dimensional point cloud data of the construction area, and dynamically adjust the height offset of the printing path of the robotic arm 3 in the Z-axis direction according to the preset design thickness of the grout layer and the horizontal requirements of the upper surface, so that the top surface of the printed grout layer is a horizontal plane and the thickness at each place is not lower than the design value.

[0040] Specifically, a 3D scanning unit is fixed to the end effector of the robotic arm 3, adjacent to the printing extrusion unit 5. The 3D scanning unit is preferably a line laser scanner based on the principle of laser triangulation or a structured light 3D camera. The 3D scanning unit is mounted with its optical axis substantially perpendicular to the construction substrate, and it has a field of view covering the width of a single printing strip and a certain area in front of it.

[0041] Before the printing job begins or during printing intervals, the robotic arm drives the 3D scanning unit to scan the target construction area. The scanning method can be a preview scan along the printing path or a raster scan of a rectangular area. The acquired raw 3D point cloud data is transmitted to the electronic control system 2, where the point cloud processing module performs the following steps: Filter the point cloud to remove noise; Using the known scanning unit and the calibration matrix of the robotic arm end effector, all point cloud data are converted to the robot base coordinate system; The processed point cloud is projected onto a horizontal plane, and a continuous surface model describing the elevation distribution of the construction base surface, namely a digital elevation model (DEM), is generated using the Delaunay triangulation method.

[0042] The core control module of the electronic control system 2 executes the following algorithm based on the generated DEM: Receive or preset the target horizontal height of the upper surface of the grout layer and minimum design thickness Two parameters; For each path point on the preset printing path ( , Y i The system queries the DEM to obtain the datum elevation value directly below the point. .

[0043] Subsequently, the Z-axis target coordinates of the robotic arm's end effector at that point are calculated according to the following logic. : Calculate the required height to ensure minimum thickness: ; To ensure the upper surface is level, the target height at this point should be taken as follows: and The larger value in, that is: .

[0044] The algorithm described above ensures that the printing thickness is at least [value missing] at any location. Furthermore, it fills the lower part of the base surface to the horizontal plane, and "lifts" the print head at the higher part of the base surface to ensure minimum thickness.

[0045] All path points calculated The Z-coordinate value is replaced in the original path to generate a corrected printing path that conforms to the base surface in three-dimensional space. During the printing process, robotic arm 3 will follow this corrected path. In continuous printing mode, the scanning unit continuously scans the area in front of the print head in real time, performing rapid online elevation compensation calculations and updates on the local path to be printed to cope with abrupt changes in the base surface or minor errors in the scanning model. Ultimately, this ensures that regardless of the base surface conditions, the printed mortar layer has a level top surface and meets the required structural thickness. This provides a precise and reliable flat base for the installation of the upper prefabricated components, fundamentally improving the construction quality and precision of prefabricated buildings.

[0046] In some embodiments, the lightweight printing robot for grouting of prefabricated components further includes a material state monitoring unit; the material state monitoring unit is disposed inside the printing extrusion unit and is used to monitor the rheological parameters and / or temperature of the grouting material; the electronic control system is configured to estimate the remaining printable time of the current batch of grouting material based on the feedback data from the material state monitoring unit and in conjunction with the built-in material hydration kinetics model, and dynamically adjust the printing strategy based on this remaining printable time; the printing strategy includes any one of adjusting the printing speed, planning the transition zone between new and old materials, and sending a warning signal to the teach pendant.

[0047] The rheological parameters of the slurry material can be monitored in real time using a high-precision pressure sensor to detect the intracavity pressure propelling the material forward. Specifically, the high-precision pressure sensor is positioned behind the screw of the extruder head in the printing extrusion unit 5 or on the inner wall of the piston cylinder. Combining the known screw speed or piston speed with the flow channel geometry, the material's apparent viscosity or yield stress can be indirectly calculated using the pipe flow equation for Bingham fluids, serving as the core rheological parameters. The temperature of the slurry material can be monitored in real time using a contact temperature sensor embedded within the material flow channel.

[0048] The material hydration kinetics model built into the electronic control system 2 is an empirical or semi-empirical mathematical model calibrated based on a large amount of experimental data. This model describes the upper limit of extrudable viscosity, a key process performance indicator of the material. The functional relationship between time t and temperature T can be simplified to:

[0049] in, The initial viscosity; This is the temperature acceleration factor, usually expressed using the Arrhenius equation; It is a time function.

[0050] The electronic control system 2 continuously receives real-time data pairs from the sensors. , Using this online data, algorithms such as Kalman filtering or least squares are employed to fine-tune and calibrate key parameters in the model in real time, enabling the model to dynamically adapt to the characteristics of the current batch of materials. Subsequently, the viscosity at the current moment is... and temperature Substituting the calibrated model and iteratively calculating forward, we predict that the viscosity will reach the threshold where it becomes unprintable. The required future time is the estimated remaining printable time. .

[0051] Electronic control system 2 according to The value determines and executes any of the following printing strategies in real time: adjusting printing speed, planning the transition area between new and old materials, or sending a warning signal to the teach pendant.

[0052] Adjusting the printing speed refers to determining the remaining print speed for the current task. If the task cannot be completed within a limited timeframe, but time is tight, the electronic control system 2 will automatically and linearly increase the robotic arm's movement speed and synchronous extrusion rate while ensuring printing quality, in order to complete the task before the material fails; if an emergency occurs... In case of abnormal shortening, the system can automatically decelerate to reduce the shear rate, which can sometimes temporarily alleviate the rapid viscosity increase caused by the thixotropy of the material, thus buying time for processing.

[0053] The planning of the transition zone between old and new materials refers to the segment where, after the electronic control system 2 issues a warning, the current material still needs to be used up, or during the switch between old and new materials, the prediction module marks the performance degradation segment predicted based on the current material state. The path planning module then automatically plans a special gradual transition path in this segment; as an example, by gradually reducing the printing linewidth or designing a cross-laid grid-like path in this area, the mechanical interlocking force between the old and new materials that are about to solidify is enhanced, specifically optimizing the mechanical properties of the joint area.

[0054] Sending a warning signal to the teach pendant refers to when When the material falls below the preset safety threshold, an audible and visual warning signal is immediately sent to the teach pendant to prompt the operator to prepare to replace the material with a new one.

[0055] like Figure 2 As shown, a lightweight printing construction method for prefabricated components using grouting is disclosed, employing the printing robot as described in any of the above embodiments, and including the following steps: S1, Site Positioning: Control the mobile chassis to move to the construction area, and use the positioning device to establish the current construction coordinate system and determine the printing origin; S2, Material preparation: Prepare the slurry using a slurry mixer and transport the slurry to the printing extrusion unit; S3, Print Initialization: Control the robotic arm to move the print extrusion unit to the print origin; S4, Automatic Printing: Controls the printing extrusion unit to start extruding the slurry, and simultaneously controls the robotic arm to move along the preset printing path to deposit the slurry onto the construction substrate. S5, Interruption and Resumption: If an interruption occurs during printing, the interruption status information is recorded; when printing resumes, the printing robot is controlled to continue the remaining printing path from the resumption starting point based on the interruption status information.

[0056] As one specific implementation of step S1, the operator issues work instructions via the teach pendant 4. The electronic control system 2 controls the mobile chassis 1 to navigate autonomously or be remotely controlled, moving it and parking it in the target construction area. Establishing the current construction coordinate system using the positioning device includes the following steps: The laser positioning device is controlled to project at least two non-collinear visible light spots onto the construction base surface as a physical spatial reference. The image acquisition unit synchronously acquires on-site images containing light spots. The electronic control system 2 runs an image processing algorithm to extract the center pixel coordinates of the light spots. Based on the pre-calibrated system parameters and the base height information, it calculates the precise three-dimensional coordinates of each light spot in the robot coordinate system. Based on the calculated light spot coordinates, a construction coordinate system is virtually defined in the software. The construction coordinate system usually sets a certain light spot as the origin and the direction of the line connecting the two points is defined as the principal axis direction. The system automatically determines the starting point of this printing task in the construction coordinate system according to the design drawings or preset rules.

[0057] As one specific implementation of step S2, using, for example Figure 3 The slurry mixer shown automatically or semi-automatically prepares the slurry material according to the mixing ratio to ensure material uniformity; the prepared slurry is injected into the printing extrusion unit 5 to prepare for printing.

[0058] As a specific implementation of step S3, the electronic control system 2 sends the coordinates of the printing origin determined in step S1 to the motion controller of the robotic arm 3. The joints of the robotic arm 3 move in coordination to position the printing extrusion unit 5 installed at its end above the origin and adjust it to the preset starting posture to complete all spatial alignment before printing.

[0059] As one specific implementation of step S4, the electronic control system 2 synchronously sends control commands to control the printing extrusion unit 5 to begin extruding the slurry at a preset initial rate, while simultaneously controlling the robotic arm 3 to begin moving along a preset printing path. During the automatic printing process, the extrusion rate is adjusted synchronously in real time according to changes in path curvature and speed to ensure uniformity of the line shape and cross-section. The slurry material is continuously extruded and deposited on the construction substrate, forming a slurry strip that conforms to the design trajectory and geometric requirements, until the entire path of the current task segment is completed.

[0060] In some embodiments, during the automatic printing process, the height of the printing path on the Z-axis is dynamically adjusted based on the real-time or pre-acquired base surface point cloud data of the 3D scanning unit to ensure that the top surface of the slurry layer is horizontal and the thickness meets the standard.

[0061] In some embodiments, during the automatic printing process, the remaining printable time is estimated in real time based on feedback from the material condition monitoring unit, and the printing speed is dynamically adjusted or warnings are issued if necessary.

[0062] In step S5, the interruption status information includes the pose of the robotic arm and chassis, the status of the extrusion unit, and the completed path points.

[0063] In some embodiments, establishing the current construction coordinate system using a positioning device includes the following steps: At least two non-collinear reference marks are projected onto the construction base surface using a positioning device. The image acquisition unit obtains the image position of the reference marks, and the absolute or relative coordinates of the construction coordinate system and the printing origin are determined after calculation by the electronic control system.

[0064] In some embodiments, the method for determining the start point of the re-printing includes the following steps: if the interruption duration is less than a first threshold, the start point of the re-printing is the spatial location of the recorded interruption point; if the interruption duration reaches or exceeds the first threshold, the start point of the re-printing is the location of the interruption point tracing back a preset distance along the printed path, so that when printing resumes, the newly printed slurry and the deposited slurry partially overlap to enhance the joint strength.

[0065] After mixing, the hydration reaction of the grouting material begins immediately, and its fluidity and bonding ability continuously decrease over time. If the interruption is prolonged, the surface of the material at the interruption point loses its activity, becoming rough or even partially set. If the grouting continues directly at the original interruption point, effective chemical bonding cannot be formed between the new and old materials; relying solely on physical contact will create a significant weak point. This results in poor overall integrity of the grouting layer, low shear strength, and easy water seepage, severely affecting the installation accuracy and structural safety of the upper precast components. By tracing back a predetermined distance along the printed path, the newly extruded, highly fluid material can wrap around and penetrate the not-yet-fully-hardened old material. This design significantly increases the effective bonding area, and through the mechanical interlocking of the new and old materials and the partial chemical bonding that can still occur in the overlapping area, it greatly improves the overall strength and density of the joint area.

[0066] In the above embodiments, the first threshold, the backtracking preset distance, and the upper limit of extrudable viscosity are... These parameters can be determined experimentally, set according to the material specifications, or input by the user according to process requirements; the first threshold is usually set between 15 and 30 minutes.

[0067] In the above embodiments, the preset printing path is obtained through one of the following methods: Generated from building information model data after slicing; It is generated by teaching the robotic arm online using a teach pendant.

[0068] The various embodiments of the present invention have now been described in detail. To avoid obscuring the concept of the invention, some details known in the art have not been described. Those skilled in the art will fully understand how to implement the technical solutions disclosed herein based on the above description.

[0069] The embodiments described above only illustrate some implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A lightweight printing robot for prefabricated component placement, characterized in that: It includes a mobile chassis and a positioning device. An electronic control system and a robotic arm are installed on the top of the mobile chassis. A teach pendant is connected to the electronic control system. A printing extrusion unit is installed at the end of the robotic arm. The teach pendant is used to plan the printing path and send the path instructions to the electronic control system. The electronic control system is used to receive and process the printing path information and the feedback signal from the positioning device, and to perform closed-loop control on the mobile chassis, robotic arm and printing extrusion unit, so that the slurry strip extruded by the printing extrusion unit is accurately deposited on the preset trajectory.

2. The lightweight printing robot for prefabricated component mounting according to claim 1, characterized in that: The electronic control system is configured to synchronously adjust the movement speed of the robotic arm and the extrusion rate of the printing extrusion unit according to the printing path information, so as to control the line shape and cross-sectional shape of the printing.

3. The lightweight printing robot for prefabricated component placement according to claim 1, characterized in that: The positioning device is a laser positioning device, which is set on the base of the mobile chassis or the robotic arm, and is used to project a positioning light spot onto the construction area. The electronic control system identifies the positioning light spot through the image acquisition unit to establish a construction coordinate system and determine the printing start origin.

4. The lightweight printing robot for prefabricated component mounting according to claim 1, characterized in that: The electronic control system also includes a task management module, which stores at least one printing task, and the printing task includes the printing path information and related process parameters. The task management module has an interruption point recording and recovery function, which can save the spatial location and equipment status information of the interruption point when the operation is interrupted, and control the operation to resume from the interruption point or the associated resume point based on the saved spatial location and equipment status information of the interruption point.

5. The lightweight printing robot for prefabricated component mounting according to claim 1, characterized in that: The end of the robotic arm is equipped with a base surface three-dimensional scanning unit; The base surface 3D scanning unit is used to acquire 3D point cloud data of the construction area; The electrical control system is configured to identify the elevation difference of the construction base surface based on the three-dimensional point cloud data of the construction area, and dynamically adjust the height offset of the printing path of the robotic arm in the Z-axis direction according to the preset design thickness of the grout layer and the horizontal requirements of the upper surface, so that the top surface of the printed grout layer is horizontal and the thickness at each point is not lower than the design value.

6. The lightweight printing robot for prefabricated component grouting according to claim 1, characterized in that, It also includes a material condition monitoring unit; The material condition monitoring unit is located inside the printing extrusion unit and is used to monitor the rheological parameters and / or temperature of the slurry material. The electronic control system is configured to estimate the remaining printable time of the current batch of slurry material based on the feedback data from the material state monitoring unit and the built-in material hydration kinetic model, and to dynamically adjust the printing strategy based on this remaining printable time. The printing strategy includes any one of the following: adjusting the printing speed, planning the transition area between new and old materials, or sending a warning signal to the teach pendant.

7. A lightweight printing construction method for prefabricated component mortar placement, employing the printing robot as described in any one of claims 1 to 6, characterized in that, Includes the following steps: Site positioning: Control the mobile chassis to move to the construction area, and use the positioning device to establish the current construction coordinate system and determine the printing origin; Material preparation: Prepare the slurry using a slurry mixer and then convey the slurry to the printing extrusion unit; Printing initialization: Control the robotic arm to move the printing extrusion unit to the printing origin; Automatic printing: The printing extrusion unit is controlled to start extruding the slurry, and the robotic arm is controlled to move along a preset printing path to deposit the slurry onto the construction substrate. Interruption and Resumption: If an interruption occurs during printing, the interruption status information is recorded; When printing resumes, based on the interruption status information, the printing robot is controlled to continue completing the remaining printing path from the starting point.

8. The lightweight printing construction method for prefabricated component grouting according to claim 7, characterized in that, Establishing the current construction coordinate system using the positioning device includes the following steps: At least two non-collinear reference marks are projected onto the construction base surface by the positioning device. The image acquisition unit obtains the image position of the reference marks, and the absolute or relative coordinates of the construction coordinate system and the printing origin are determined by the electronic control system.

9. The lightweight printing construction method for prefabricated component grouting according to claim 7, characterized in that, The method for determining the starting point of the continued construction includes the following steps: If the interruption duration is less than the first threshold, then the start point of the reconstruction is the spatial location of the recorded interruption point; If the interruption duration reaches or exceeds the first threshold, the start point for resuming printing is the position at which the interruption point is traced back a preset distance along the printed path, so that when printing resumes, the newly printed slurry and the already deposited slurry partially overlap to enhance the joint strength.

10. The lightweight printing construction method for prefabricated component grouting according to claim 7, characterized in that, The preset print path is obtained through one of the following methods: Generated from building information model data after slicing; This is generated by teaching the robotic arm online using the teach pendant.

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