AGV robot stacking system and method for butt joint of milk filling line and storage line

Abstract

The invention discloses an AGV robot stacking system and method for butt joint of a milk filling line and a storage line. The AGV robot stacking system comprises a guide rail type AGV, a dragging platform, a flexible lateral constraint execution module, a vehicle condition monitoring module, a visual monitoring module and a processing module. According to the invention, the air bag type side embracing module is arranged, and the processing module converts the inclination state data obtained by visual monitoring into a static pressure compensation component, converts the operation state data obtained by vehicle condition monitoring into a dynamic pressure correction component, and then performs real-time superposition to generate a target pressure value; interlayer micro-slip accumulation and inclination angle increase of high-gravity-center cup / bowl dairy product stacks in the transportation process are directly restrained, and then the anti-overturning margin and the butt joint carrying reliability are further improved on the premise that efficiency and safety are guaranteed; catastrophic stack transfer accidents caused by uncontrollable factors such as upstream wrapping film breakage or serious partition plate deformation are effectively prevented, and operation safety of an unmanned workshop is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of AGV (Automated Guided Vehicle) technology, and in particular to an AGV robot palletizing system and method for docking milk filling lines and storage lines. Background Technology

[0002] Milk bottling lines produce cup-packaged milk and bowl-packaged dairy products, typically characterized by high cycle time and continuous output. Individual cup / bowl containers are trapezoidal, wider at the top and narrower at the bottom. When stacked, these containers form a non-perpendicular, stepped stack, resulting in poor center of gravity control and lateral stability. Current technologies use flat plastic or corrugated cardboard partitions or stretch film to constrain the stacked cup or bowl-packaged dairy products, thus forming a stack.

[0003] To achieve automated connection between filling and warehousing lines, the industry commonly uses automated conveyor lines, lifting and transfer mechanisms, and AGV / AMR handling equipment. Finished product cartons are transferred from the filling end to the buffer area, storage entrance, or automated storage and retrieval system (AS / RS) conveyor line for automated warehousing or palletizing. However, cup or bowl-packaged dairy products, when stacked, have a large upper proportion and a high center of gravity, resulting in low overturning margin and extreme sensitivity to lateral disturbances, rapid acceleration / deceleration, and turning inertia. Furthermore, the route connecting the milk filling and warehousing lines may contain ground cracks or uneven surfaces, leading to a superposition of vibrations and inertial disturbances, further amplifying the low overturning margin caused by the high center of gravity of cup or bowl-packaged dairy product stacks during transportation.

[0004] Therefore, it is necessary to design an AGV robot palletizing system and method for docking milk filling lines and storage lines to solve the problem of stacks of cup or bowl-packaged dairy products tipping over due to ground cracks or uneven ground. Summary of the Invention

[0005] This invention overcomes the shortcomings of the prior art and provides an AGV robot palletizing system and method for docking milk filling lines and storage lines.

[0006] To achieve the above objectives, the technical solution adopted by this invention is: an AGV robot palletizing system for docking milk filling lines and storage lines, comprising:

[0007] The guide rail type AGV trolley runs along a physical track fixedly installed on the ground. The bottom of the guide rail type AGV trolley is provided with a set of guide wheels that match the inner contour of the physical track.

[0008] The towing platform is installed at the bottom of the guide rail AGV trolley and is connected to the servo motor drive through a vertically arranged ball screw pair to realize lifting and lowering movement along the Z-axis.

[0009] The flexible lateral restraint execution module is located around the towing platform and includes two sets of symmetrically arranged airbag-type side restraint modules. Each set of airbag-type side restraint modules includes a flexible bladder and a pressure regulating valve.

[0010] A vehicle condition monitoring module, integrated into the internal controller of the guide rail AGV, is used to collect the operating status data of the AGV; and

[0011] The processing module is connected to both the vehicle condition monitoring module and the airbag-type side restraint module. It is used to process the operating status data, calculate the corresponding target pressure value, and send control commands to the airbag-type side restraint module to adjust the magnitude of the flexible restraint force in real time.

[0012] In a preferred embodiment of the present invention, the vehicle condition monitoring module includes at least one of an inertial measurement unit and a drive encoder, and is used to output the AGV vehicle's running status data, which includes at least: longitudinal acceleration of the vehicle body, lateral acceleration of the vehicle body, angular velocity of the vehicle body about the vertical axis, and vehicle speed.

[0013] The operating status data is sent to the processing module according to the sampling period;

[0014] The processing module determines the target airbag pressure or target pressure change rate of the airbag-type side-hug module based on the velocity, acceleration, and / or angular velocity data.

[0015] In a preferred embodiment of the present invention, the guide rail AGV is further provided with a visual monitoring module, including an industrial camera and / or a depth camera, and is installed on the towing platform for collecting the posture information of the entire stack of goods and outputting tilt state data; wherein, the tilt state data includes at least the tilt angle and tilt direction of the entire stack of goods relative to the vertical direction.

[0016] In a preferred embodiment of the present invention, the processing module is used to convert the cargo tilt state data output by the visual monitoring module into a static pressure compensation component, and to convert the motion state data output by the vehicle condition monitoring module into a dynamic pressure correction component.

[0017] The target pressure value is generated by using the static pressure compensation component as the reference pressure component, and the dynamic pressure correction component is superimposed in real time during the operation of the guide rail AGV to update the target pressure value; and an upper pressure limit and a lower pressure limit are set for the target pressure value.

[0018] In a preferred embodiment of the present invention, the processing module is used to generate a left target pressure value and a right target pressure value for two sets of symmetrically arranged airbag side-holding modules, and determine a differential compensation amount according to the tilt direction and / or the lateral acceleration, so that the left target pressure value and the right target pressure value are respectively increased or decreased by the differential compensation amount based on the target pressure value, so as to form a differential flexible constraint force to counteract the tilt trend.

[0019] In a preferred embodiment of the present invention, each group of airbag-type side-hug modules further includes a pressure sensor for detecting the actual airbag pressure and feeding it back to the processing module;

[0020] The processing module controls the pressure regulating valve to inflate or deflate the airbag based on the pressure deviation between the target pressure value and the actual airbag pressure, and sets an upper limit for the pressure change rate of the target pressure value so that the airbag pressure is adjusted to change continuously.

[0021] An AGV robot palletizing method for connecting milk filling lines and storage lines, using the aforementioned AGV robot palletizing system for connecting milk filling lines and storage lines, includes the following steps:

[0022] Step S1: In the static stage before the start of the guide rail AGV, the posture information of the entire stack of goods is collected by the vision monitoring module. The processing module calculates the initial tilt angle and tilt direction based on the posture information and converts them into static pressure compensation components, which serve as the reference pressure value of the airbag side-holding module.

[0023] Step S2: The vehicle condition monitoring module collects real-time operating status data and sends it to the processing module. The processing module calculates the dynamic pressure correction component based on acceleration and speed changes.

[0024] Step S3: The processing module performs real-time superposition calculation on the static pressure compensation component and the dynamic pressure correction component to generate a target pressure value, and sends a control command to the pressure regulating valve of the airbag side clamping module to make the airbag pressure track the target pressure value, thereby achieving flexible constraint on the entire stack of goods.

[0025] In a preferred embodiment of the present invention, in step S1, the static pressure compensation component acts differentially on two sets of symmetrically arranged airbag side-hugging modules, so that the airbags closer to the tilt direction establish a higher reference pressure, and the airbags away from the tilt direction establish a relatively lower reference pressure.

[0026] The processing module performs differential correction on the two airbags based on the lateral acceleration and / or angular velocity directions in the operating status data to form a differential flexible constraint force that counteracts the tilting trend.

[0027] In a preferred embodiment of the present invention, in step S3, the processing module sets a lower pressure limit and an upper pressure limit for the target pressure value, and sets an upper limit for the pressure change rate, so that the target pressure value changes continuously under the conditions of amplitude and speed limit; wherein, the static pressure compensation component is updated according to the visual update cycle, and the dynamic pressure correction component is updated according to the vehicle condition update cycle.

[0028] In a preferred embodiment of the present invention, a safety policy is triggered when an anomaly criterion is met. The anomaly criterion includes at least: the tilt angle exceeds a tilt threshold, the actual airbag pressure cannot track the target pressure value within a preset time, or the operating status data exceeds a safety threshold.

[0029] The safety strategy includes at least: switching the target pressure value to the reinforcement pressure and / or controlling the airbag side-hugging module to depressurize to a safe pressure, and controlling the guide rail AGV to enter a speed-limited operation or stop operation state.

[0030] This invention addresses the shortcomings of the prior art and has the following beneficial effects:

[0031] (1) This invention provides an AGV robot palletizing system for docking milk filling lines and storage lines. By setting up an airbag-type side-hugging module, and having the processing module convert the tilt state data obtained by visual monitoring into a static pressure compensation component and the running state data obtained by vehicle condition monitoring into a dynamic pressure correction component, the target pressure value is generated in real time by superimposing the data. This directly suppresses the accumulation of interlayer micro-slippage and the increase of tilt angle of high-center-of-gravity cup / bowl-shaped dairy product stacks during transportation. This further improves the anti-overturning margin and docking and handling reliability while ensuring efficiency and safety. It effectively prevents catastrophic stacking accidents caused by uncontrollable factors such as upstream wrapping film breakage or severe deformation of partitions, and ensures the safe operation of unmanned workshops.

[0032] (2) The present invention generates target pressure values ​​on the left and right sides by setting two sets of symmetrical airbag side-hugging modules respectively, and determines the differential compensation amount according to the tilt direction and / or lateral acceleration direction to achieve reverse adjustment of pressure on both sides, thereby dynamically distributing pressure according to the disturbance direction, directly improving the anti-overturning moment and anti-side slip capability under turning and eccentric loading conditions.

[0033] (3) By setting up a visual monitoring module, the present invention can acquire and output tilt state data of tilt angle and tilt direction of the whole stack of goods in real time, so that the processing module can identify the initial tilt and center of gravity offset of the stack before the AGV starts, and convert the tilt state data into static pressure compensation component, and establish a benchmark flexible lateral constraint force that matches the tilt trend in advance, so as to complete the pre-tightening and straightening and risk suppression before the tilt trend develops into interlayer slippage or overturning, thereby improving the posture stability and anti-overturning reliability of the whole stack of cup / bowl dairy products during transportation and docking.

[0034] (4) By setting up a vehicle condition monitoring module, the present invention collects and outputs the running status data of vehicle speed, acceleration and angular velocity in real time and converts them into static pressure correction components. This enables the processing module to sense the inertial disturbance and vibration impact intensity of the AGV road condition in a timely manner and continuously adjust the pressure of the airbag side clamping module. It can quickly increase the lateral restraint force at the moment the disturbance occurs and release the excess clamping stress in time when the disturbance weakens. This effectively offsets the destructive effect of dynamic inertial force and centrifugal force on the high center of gravity stack and makes up for the inadequacy of static reference pressure in dealing with violent motion conditions, thereby suppressing the accumulation of interlayer slippage and dynamic instability. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the guide rail type AGV trolley structure of a preferred embodiment of the present invention;

[0037] Figure 2 This is a flowchart of a preferred embodiment of the present invention for an AGV robot palletizing method for docking a milk filling line and a storage line;

[0038] In the diagram: 1. Guide rail AGV trolley; 2. Towing platform; 3. Airbag side-clamping module; 4. Vehicle condition monitoring module. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein. Therefore, the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0041] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0042] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.

[0043] Example 1:

[0044] In dairy factories, AGVs connect milk filling lines and storage lines. However, in real factory environments, ground cracks, seams, local settlement, or slight slope changes are often unavoidable. When AGVs transport stacks of goods, ground cracks or uneven ground can cause vibrations and inertial disturbances to overlap, leading to the stacks of goods tipping over. This is especially true for cup or bowl milk, which has a trapezoidal structure with a larger top and smaller bottom, resulting in a stepped side, a high center of gravity, and low anti-tipping margin.

[0045] Existing technologies typically control the movement speed of AGVs through control algorithms, allowing the AGVs to adjust their speed in real time according to different road conditions during transportation. This reduces the AGVs' handling speed and consequently lowers their transportation and handling rate.

[0046] In this embodiment, the AGV robot palletizing system for docking the milk filling line and the storage line includes at least a rail-guided AGV trolley 1 and a towing platform 2. The rail-guided AGV trolley 1 runs along a physical track fixed to the ground, and the bottom of the trolley is provided with a set of guide wheels that match the inner contour of the physical track, so that the trolley can be guided within the side wall or groove contour of the track.

[0047] The physical track can be in the form of steel rails, aluminum profile rails or trough rails, etc. It is laid in a fixed manner along the path from the end of the milk filling line to the warehouse entrance, and is connected to the ground foundation by means of expansion bolts, chemical anchors or embedded parts.

[0048] Expansion joint matching sections and transition splicing sections can be set along the track to maintain continuous contour constraints when the temperature changes or the ground undergoes slight deformation.

[0049] The guide wheel assembly preferably adopts a combination structure of at least one set of lateral guide wheels and at least one set of load-bearing wheels: the lateral guide wheels roll in contact with the inner contour of the track to suppress lateral clearance and limit the lateral attitude of the trolley; the load-bearing wheels are used to bear the load of the car body and cargo and roll along the track direction, thereby achieving the kinematic constraints of the guide rail with free longitudinal movement and restricted lateral and yaw movement in the structure.

[0050] The towing platform 2 is installed at the bottom of the guide rail AGV trolley 1 and is connected to the servo motor drive through a vertically arranged ball screw pair to realize lifting and lowering movement along the Z-axis.

[0051] In this embodiment, the Z-axis lifting of the towing platform 2 is used to connect to the shelves or transfer mechanism on one side of the milk filling line and the shelves or conveyor interface on the other side of the storage line. Its function is to ensure smooth load transfer when the entire stack of goods is moved from the filling line side to the platform or from the platform to the storage line side by moving the entire stack of goods up and down.

[0052] In the operation of this embodiment, after receiving the handling task at the standby position on the side of the filling line, the guide rail AGV 1 travels along the physical track to the docking point at the end of the filling line.

[0053] Since the track path is fixed, the AGV does not need to rely on ground QR codes, laser SLAM or visual positioning to repeatedly correct its lateral position when approaching the point. Its lateral position and yaw angle are naturally determined by the track contour constraint, thereby reducing the accumulation of lateral disturbances caused by the correction action to the stack.

[0054] Driven by a servo, the towing platform 2 descends along the Z-axis to the docking height with the transfer mechanism on the filling line side. The robotic arm or transfer mechanism on the filling line side pushes or transfers the entire stack of goods to the bearing surface of the towing platform 2. After the towing platform 2 rises to the transportation height, the AGV travels along the track to the docking point on the storage line side, and delivers the entire stack of goods to the storage line shelf or conveyor interface by descending the platform at the docking point, completing one docking and handling cycle.

[0055] This embodiment isolates random disturbances caused by uneven ground at the track base layer using guide rails, and switches the AGV's motion reference from ground contact constraint to track contour constraint. Therefore, in cases where there are cracks, seams, or local unevenness on the ground, the instantaneous lateral sway caused by tires driving over cracks, which is then rigidly transmitted to the high center of gravity of the cargo stack, is significantly reduced. At the same time, the guide rail constraint makes it easier for the AGV to achieve high speed and high repeatability, reducing the cycle time drop caused by ground factors from the source.

[0056] Considering the special fragility of cup / bowl stacks, this embodiment adds a flexible lateral clamping mechanism, such as an inflatable airbag, to the guide rail AGV to provide gentle support and vibration reduction for the stack during handling.

[0057] Example 2:

[0058] During the high-speed movement of the guide rail AGV trolley 1, although the stack is clamped by inflatable airbags, the inertia of the stack can cause dynamic disturbances to the entire stack of goods when passing through sections such as turns and downhill. For the entire stack of cups / bowls, the dynamic disturbances are not only manifested as overall shaking, but more importantly, they may cause the accumulation of micro-slippage between layers: a sudden deceleration causes the upper layer to have a very small displacement relative to the lower layer, and the next sudden acceleration reverses the direction of displacement. If there is a lack of damping energy absorption and lateral restraint, the micro-slippage will gradually amplify in multiple cycles, eventually manifesting as the appearance of the stack tilting, an increased center of gravity shift, or even overturning due to rigid collision at the moment of docking.

[0059] Existing technologies generally require deceleration to avoid excessive speed, which could cause dynamic disturbances in the stack. However, if safety is compromised by reducing speed, the efficiency advantage of the guide rail AGV cannot be fully utilized. This embodiment aims to upgrade stabilization from static fixed restraint to flexible constraint that is dynamically adjustable according to vehicle conditions. Specifically, an airbag-type side-holding module 3 and a vehicle condition monitoring module 4 are set around the towing platform 2. During short-term windows of increased vehicle disturbance, the airbag pressure is increased to increase lateral friction and damping energy absorption. When vehicle disturbance is small, the airbag pressure is reduced to avoid excessive pressure on the packaging, thereby achieving the maximum dynamic stabilization benefit with minimal long-term side effects.

[0060] Therefore, based on the guide rail AGV trolley 1 and towing platform 2 in Embodiment 1, this embodiment further includes a flexible lateral constraint execution module, a vehicle condition monitoring module 4, and a processing module.

[0061] The flexible lateral restraint execution module is set around the towing platform 2, including two sets of symmetrically arranged airbag-type side-holding modules 3. Each set of airbag-type side-holding modules 3 includes a flexible bladder and a pressure regulating valve. The flexible bladder forms a flexible contact with the side of the entire stack of goods. It is not for rigid clamping, but for providing adjustable damping and adjustable lateral restraint. It can absorb some energy and suppress interlayer slippage when the vehicle dynamic disturbance is input.

[0062] The vehicle condition monitoring module 4 is integrated into the internal controller of the guide rail AGV trolley 1 and is used to collect the operating status data of the AGV trolley. The processing module is connected to the vehicle condition monitoring module 4 and the airbag side clamping module 3 respectively. It is used to process the operating status data and calculate the target pressure value, and then send control commands to the pressure regulating valve to adjust the airbag pressure in real time.

[0063] The vehicle condition monitoring module 4 may include at least one of an inertial measurement unit (IMU), a drive encoder, or a wheel speed encoder, for outputting operating status data including at least the vehicle body longitudinal acceleration, vehicle body lateral acceleration, vehicle body angular velocity about the vertical axis, and vehicle speed, and sending them to the processing module according to the sampling period.

[0064] The processing module does not need to identify the location of ground cracks or the angle of slope, because the guide rail structure has removed ground uncertainty from the main control object; the processing module makes dynamic stabilization decisions based on the intensity of the inertial disturbance that the vehicle is applying to the stack at this moment.

[0065] During the static preparation phase, before the guide rail AGV trolley 1 loads a stack of goods and is ready to start, the processing module sets a baseline pressure based on process constraints such as the type of goods, the height of the stack, and the amount of lateral compression that the packaging can withstand.

[0066] The baseline pressure is not necessarily better the higher it is, mainly because excessive continuous pressure may cause deformation or local indentation of the cup / bowl packaging, or even cause pressure concentration and induce new slippage risks when the partition is slightly uneven. Therefore, the baseline pressure is preferably set to a pressure level that just forms a flexible fit and provides basic damping, so that the airbag provides only gentle lateral restraint when there is no significant vehicle disturbance, leaving a margin for pressurization during dynamic phases.

[0067] During the dynamic operation phase, the processing module maps the speed, acceleration, and angular velocity output by the vehicle condition monitoring module 4 into dynamic pressure correction components. Since the intensity of the vehicle's disturbance to the stack is related to inertia, and inertia is directly related to the acceleration amplitude; during turning or docking attitude adjustments, angular velocity and velocity together determine the lateral inertial tendency. Therefore, it can be generated using one of the following methods: .in , where are non-negative weighting coefficients, representing the contributions of longitudinal start-stop inertia, lateral disturbance, and yaw rotation to the stability requirement, respectively. Indicates the longitudinal acceleration of the vehicle body. Indicates the lateral acceleration of the body. This represents the angular velocity of the vehicle body about its vertical axis. This represents the vehicle speed at time t.

[0068] When the AGV moves straight at a constant speed and the disturbance is small, the longitudinal acceleration, lateral acceleration and angular velocity of the vehicle body about the vertical axis are all small, the dynamic pressure correction component approaches 0, and the airbag remains gentle.

[0069] When the AGV starts or stops at high speed or enters a curved section, the relevant terms increase, and the airbag pressure increases accordingly to increase lateral friction and damping energy absorption, thereby suppressing the cumulative amplification of interlayer micro-slippage.

[0070] Based on dynamic pressure correction components The target pressure can be generated by the following formula: ,in Indicates the reference pressure. Indicates the lower limit of pressure. Indicates the upper limit of pressure. This means that the values ​​of the dynamic pressure correction component and the reference pressure are limited to between the upper and lower pressure limits.

[0071] To avoid abrupt changes in lateral force on the stack caused by pressure step jumps, the processing module limits the rate of pressure change, ensuring that pressure adjustment is continuous. .in, This indicates the upper limit of the rate of change of pressure.

[0072] In this embodiment, each airbag-type side-hug module 3 can be equipped with a pressure sensor to detect the actual airbag pressure and feed it back to the processing module; the processing module controls the pressure regulating valve to inflate or deflate according to the deviation between the target pressure and the actual airbag pressure, so that the actual pressure tracks the target pressure, while being constrained by the upper limit of the pressure change rate to achieve smooth adjustment.

[0073] Since this embodiment mainly addresses the risk of inertia during high-speed start-stop, the two airbags can achieve overall enveloping damping by using the same target pressure in most cases. When it is necessary to further counteract the lateral inertial direction, a slight differential can be made based on the lateral acceleration of the vehicle body without introducing additional visual information. For example, when the lateral acceleration is pointing to the left, the left side is slightly pressurized and the right side is slightly depressurized. However, the differential amplitude is preferably smaller than the differential amplitude based on visual tilt in embodiment 3, so as to avoid excessive differential adjustment leading to reverse compression when there is a lack of tilt direction confirmation.

[0074] This embodiment does not rely on a general speed reduction strategy for safety. Instead, without sacrificing the high-speed advantage of the rail-guided AGV, it achieves dynamic stabilization through vehicle condition monitoring and dynamic airbag pressurization: the stronger the vehicle disturbance, the more pressurized the airbag; after the disturbance disappears, the pressure drops, thereby avoiding the risk of packaging damage or fatigue caused by long-term high pressure.

[0075] More importantly, since the guide rail structure has significantly reduced ground uncertainty, the control object in this embodiment is simplified to a closed-loop relationship of vehicle condition disturbance - airbag pressure - stabilization effect. Unlike traditional ground-type AGVs, it does not need to incorporate cracks, slopes, joint positions, etc. into complex road condition adaptive control, thus simplifying the control strategy at the system level.

[0076] Example 3:

[0077] Currently, cup / bowl-packaged products are perfectly stacked, with absolutely flat partitions and constant and full coverage stretch film tension, thus maintaining good integrity during transportation. However, in reality, a slightly bent partition or a slight tilt when the palletizing robot places the partition may lead to uneven pressure distribution and create a slippage hazard. Film breakage, unstable tension, fluctuations in the quality of the film itself, or insufficient coverage in some areas may also cause insufficient binding force in some areas, making the stack appear stable on the surface but with instability trigger points inside.

[0078] At this point, although the guide rail AGV provides an extremely stable operating benchmark, its high speed, high acceleration and high rigidity create a new contradiction with the low tolerance, shock resistance and defects of the fragile stack: the inertial force of high-speed start and stop and the rigid collision of precise docking cause the goods to suddenly become unstable during transportation or docking.

[0079] like Figure 1 As shown, based on this, this embodiment introduces a visual monitoring module on the basis of vehicle condition monitoring and airbag stabilization. The module obtains the tilt state data of the entire stack of goods through vision, including the tilt angle and tilt direction. The processing module converts the tilt state into a static pressure compensation component and first performs a tilt-based directional correction on the airbag pressure.

[0080] Subsequently, during the operation of the guide rail AGV, the vehicle condition is converted into a dynamic pressure correction component, and the airbag pressure is dynamically corrected a second time based on the vehicle condition. This achieves a collaborative control logic of first correcting the bias and then suppressing dynamic disturbances, which not only eliminates the initial tilt and hidden dangers caused by the bending of the partition or the problem of the wrapping film, but also copes with the tilt caused by the bending of the partition or the problem of the wrapping film induced by the transient inertial impact of high-speed operation.

[0081] This embodiment adds a visual monitoring module to embodiment 2. The visual monitoring module may include an industrial camera and / or a depth camera, which is installed at a suitable position above or to the side of the towing platform or towing platform 2, so that its field of view covers the key contour features of the entire stack of goods, such as the bottom edge line of the stack, the side step line, the outer contour of the wrapping film, etc., and is used to collect the posture information of the entire stack of goods and output tilt state data.

[0082] Key contour features include the bottom edge line of the stack, the side stepped lines, and the outer contour of the wrapping film.

[0083] The tilt status data includes at least the tilt angle of the entire stack of goods relative to the vertical direction and the tilt direction information. The tilt direction can be represented by left / right or a direction symbol relative to the vehicle coordinate system.

[0084] The processing module is connected to the visual monitoring module, the vehicle condition monitoring module 4 and the airbag side-hug module 3 respectively. It is used to fuse the tilt state data and the operating state data and generate the target pressure value. At the same time, it sets the upper limit and lower limit of pressure and the upper limit of pressure change rate to ensure that the airbag pressure adjustment is continuous and controllable.

[0085] In the static phase before the start of the guide rail AGV trolley 1, the vision monitoring module first collects the posture of the loaded stack of goods, and the processing module calculates the initial tilt angle and tilt direction based on the posture information.

[0086] By identifying the tilt and establishing a pressure bias to counteract the tilting trend, the stack is brought back to a safer neutral state before startup, or at least the initial conditions for the tilt to continue developing are reduced. To this end, the processing module converts the tilt angle into a static pressure compensation component. For example, the following linear mapping can be used: .in, This is a non-negative coefficient, reflecting the calibration relationship of how much pressure compensation is required per unit tilt angle. This represents the tilt angle of the entire stack of goods at time t.

[0087] The processing module generates differential reference pressure on the left and right sides based on the reference pressure, increasing pressure on the tilting side and decreasing pressure on the diverging side, thereby creating a differential flexible constraint force to counteract the tilting trend. The left and right references in the static phase can be expressed in the following form: .

[0088] in, Indicates the target pressure of the left airbag. Indicates the target pressure of the right airbag. Indicates the direction of tilt; when tilting to the left... When tilted to the right

[0089] This means that when the stack tilts to the left, the pressure of the left airbag increases, allowing the flexible airbag to provide stronger surface contact support, friction, and damping energy absorption on the tilted side, thus inhibiting the tilt from continuing to the left. The pressure on the right side decreases accordingly, avoiding the overall rigidity caused by high pressure on both sides, thereby reducing the risk of secondary slippage caused by rigid top pressure. This static differential offset is the first correction, which is aimed at the initial tilt and uneven pressure distribution caused by the bending of the partition or the problem of the wrapping film.

[0090] After the guide rail AGV enters the dynamic operation phase, the vehicle condition monitoring module 4 outputs the vehicle's longitudinal acceleration, lateral acceleration, angular velocity around the vertical axis, and speed according to the sampling period. The processing module converts these into dynamic pressure correction components. This is to address transient inertial shocks caused by high-speed start-stop, curved sections, and attitude adjustments before docking. The dynamic correction component can follow the form of Example 2: .

[0091] The dynamic correction component works by superimposing air pressure on both sides while maintaining the static differential bias, thereby synchronously increasing the damping capacity of both airbags within a short window of increased disturbance, thus absorbing energy and suppressing the accumulation of interlayer micro-slippage. This is the first part of the second correction, which targets the intensity of vehicle dynamic disturbance.

[0092] Furthermore, to enable the system to continuously counteract the tilting trend during dynamic operation rather than only before startup, this embodiment allows the processing module to generate differential compensation based on the tilt direction and / or lateral acceleration direction. This allows the left and right pressures to further create a dynamic differential on top of the superimposed air pressure, thereby achieving dynamic righting. The differential compensation amount can be affected by both the tilt direction and the lateral inertial direction simultaneously, for example, by adopting one of the following forms: .

[0093] in, and The first term indicates a non-negative coefficient. The first term reflects the greater the tilt, the greater the need for differential correction, while the second term reflects the stronger the lateral inertia, the greater the need for damping on the opposite side of the inertial direction. Indicates the direction of lateral acceleration, when When pointing to the left ,when When pointing to the right The symbols mentioned above are only used to express the differential direction. Based on this, the pressure on the left and right targets can be written as:

[0094]

[0095] .

[0096] Similarly, an upper limit for the rate of pressure change is set to ensure continuous pressure adjustment and avoid vibration caused by frequent differential movements or sudden changes in force caused by pressure steps. Thus, this embodiment provides a low-frequency reference offset for the stack's own state through visual monitoring and high-frequency dynamic correction for vehicle disturbances through vehicle condition monitoring. In the processing module, static pressure compensation components and dynamic pressure correction components are synergistically superimposed, and differential compensation is introduced when necessary to counteract tilting trends, thereby significantly improving stability without sacrificing high-speed docking efficiency.

[0097] In this embodiment, each airbag-type side-hugging module 3 is equipped with a pressure sensor to detect the actual airbag pressure and feed it back to the processing module. The processing module controls the pressure regulating valve to inflate or deflate based on the deviation between the target pressure and the actual pressure, so that the airbag pressure tracks the target pressure value. At the same time, it sets an upper limit and a lower limit for the target pressure to avoid overpressure damage to the packaging or underpressure leading to insufficient restraint, and smooths the pressure adjustment by setting an upper limit for the pressure change rate.

[0098] To prevent milk leakage caused by the entire stack tipping over, the processing module can also be set with anomaly criteria and safety strategies: when the tilt angle detected by vision exceeds the tilt threshold, or the tilt angle shows a monotonically increasing trend within several consecutive control cycles, or the actual airbag pressure cannot track the target pressure within a preset time, the processing module triggers a protection mode, such as switching the target pressure to the reinforcement pressure and simultaneously controlling the guide rail AGV trolley 1 to enter a speed-limited operation or stop operation state, so as to block the unstable chain before the risk gets out of control and prevent leakage and contamination of the track.

[0099] This invention eliminates the main sources of uncertainty at the structural level by using a guide rail AGV, so that the AGV motion control strategy no longer needs to make complex real-time decisions around the ground, thus enabling high-speed movement. At the same time, it resolves the contradiction between high-speed, high-rigidity handling and fragile stack defects. In this embodiment, the tilt state is obtained visually and static straightening is performed first, followed by dynamic correction of the vehicle condition. This changes the stabilization strategy from passive deceleration to active flexible constraint, reducing the probability of instability triggered by upstream defects while maintaining a high cycle time.

[0100] In other words, this embodiment transforms the system from complex motion control to adapt to uncertain ground conditions to simplified motion control and stable closed-loop absorption of uncertain stack states. The guide rail structure and airbag-stabilized closed-loop simplify the AGV trolley control strategy, and can maintain stable operation, especially in high-speed docking scenarios.

[0101] In summary, given the stable baseline and high efficiency provided by the guide rail AGV, the tilt angle and tilt direction of the pallet are explicitly introduced into the closed loop through the visual monitoring module. First, a static pressure compensation component is generated to directionally correct the airbag pressure to eliminate or suppress the tilting trend caused by initial defects. Then, a dynamic pressure correction component is generated based on the vehicle condition and differential compensation is superimposed when necessary. This makes the airbag stability capability enhanced in real time with high-speed start-stop, turning and docking disturbances, thereby reducing the systemic risks of tilt accumulation, overturning and leakage contamination of the track. At the same time, it eliminates the need for complex real-time adaptation to ground cracks, slopes, etc.

[0102] like Figure 2 As shown, an AGV robot palletizing method for connecting milk filling lines and storage lines, using an AGV robot palletizing system for connecting milk filling lines and storage lines, includes the following steps:

[0103] Step S1: In the static stage before the start of the guide rail AGV trolley 1, the posture information of the whole stack of goods is collected by the vision monitoring module. The processing module calculates the initial tilt angle and tilt direction based on the posture information and converts them into static pressure compensation components, which serve as the reference pressure value of the airbag side gripping module 3.

[0104] Step S2: The vehicle condition monitoring module 4 collects real-time operating status data and sends it to the processing module. The processing module calculates the dynamic pressure correction component based on acceleration and speed changes.

[0105] Step S3: The processing module performs real-time superposition and calculation of the static pressure compensation component and the dynamic pressure correction component to generate a target pressure value, and sends a control command to the pressure regulating valve of the airbag side clamping module 3 so that the airbag pressure tracks the target pressure value, thereby achieving flexible constraint on the entire stack of goods.

[0106] In a preferred embodiment of the present invention, in step S1, the static pressure compensation component acts differentially on two sets of symmetrically arranged airbag side-hugging modules 3, so that the airbags on the side closer to the tilt direction establish a higher reference pressure, and the airbags on the side away from the tilt direction establish a relatively lower reference pressure.

[0107] The processing module performs differential correction on the two airbags based on the lateral acceleration and / or angular velocity directions in the operating status data to form a differential flexible constraint force to counteract the tilting trend.

[0108] In a preferred embodiment of the present invention, in step S3, the processing module sets a lower pressure limit and an upper pressure limit for the target pressure value, and sets an upper limit for the pressure change rate, so that the target pressure value changes continuously under the conditions of amplitude and speed limit; wherein, the static pressure compensation component is updated according to the visual update cycle, and the dynamic pressure correction component is updated according to the vehicle condition update cycle.

[0109] In a preferred embodiment of the present invention, a safety policy is triggered when an anomaly criterion is met. The anomaly criterion includes at least: the tilt angle exceeds the tilt threshold, the actual airbag pressure cannot track the target pressure value within a preset time, or the operating status data exceeds the safety threshold.

[0110] The safety strategy includes at least: switching the target pressure value to the reinforcement pressure and / or controlling the airbag-type side-hugging module 3 to release pressure to a safe pressure, and controlling the guide rail AGV trolley 1 to enter a speed-limited operation or stop operation state.

[0111] When this invention is used, the guide rail type AGV trolley 1 runs back and forth between the milk filling line and the storage line along the pre-laid physical guide rail. Since the lateral position and yaw attitude of the AGV trolley are constrained by the guide rail profile, its operation process no longer directly depends on the flatness of the ground. The influence of ground cracks, joints and local slope changes on the trolley attitude is effectively isolated.

[0112] After the AGV trolley loads a stack of cup- or bowl-packaged dairy products and starts operating, the vehicle condition monitoring module 4 collects real-time operating status data of the trolley, including information such as speed, acceleration, and angular velocity. The processing module determines the intensity of inertial disturbance corresponding to the current operating stage based on the operating status data, and accordingly corrects the airbag pressure of the airbag-type side-holding module 3 set around the towing platform 2. This ensures that during stages with large inertial disturbances, such as when the trolley starts, stops, accelerates, decelerates, or turns, the airbag pressure is increased accordingly to enhance the flexible lateral restraint and damping energy absorption capacity of the stack of goods. When the operating status is stable, the airbag pressure is reduced to the reference pressure level, thereby avoiding long-term high pressure causing compression damage to the packaging structure.

[0113] Before or during the operation of the trolley, the visual monitoring module collects the posture of the entire stack of goods and generates tilt state data. The processing module determines the tilt direction and degree of the entire stack of goods based on the tilt state data. First, it performs differential correction on the target pressure of the airbags on the left and right sides based on the tilt state data, so that the airbag on the tilt side forms a higher reference constraint pressure to offset the initial tilting risk caused by upstream process defects such as partition bending, stacking offset, or uneven wrapping film binding. On this basis, the processing module combines the operating status data output by the vehicle condition monitoring module 4 to dynamically correct the airbag pressure, so that the airbag pressure simultaneously reflects the posture state of the goods themselves and the inertial disturbance generated by the vehicle operation. Thus, under the conditions of high speed and high acceleration of the guide rail operation, it can continuously suppress the tilting trend of the entire stack of goods.

[0114] Based on the preferred embodiments of the present invention described above, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. An AGV robot palletizing system for docking milk filling lines and storage lines, characterized in that, include: The guide rail type AGV trolley runs along a physical track fixedly installed on the ground. The bottom of the guide rail type AGV trolley is provided with a set of guide wheels that match the inner contour of the physical track. The towing platform is installed at the bottom of the guide rail AGV trolley and is connected to the servo motor drive through a vertically arranged ball screw pair to realize lifting and lowering movement along the Z-axis. The flexible lateral restraint execution module is located around the towing platform and includes two sets of symmetrically arranged airbag-type side restraint modules. Each set of airbag-type side restraint modules includes a flexible bladder and a pressure regulating valve. A vehicle condition monitoring module, integrated into the internal controller of the guide rail AGV, is used to collect the operating status data of the AGV; and The processing module is connected to both the vehicle condition monitoring module and the airbag-type side restraint module. It is used to process the operating status data, calculate the corresponding target pressure value, and send control commands to the airbag-type side restraint module to adjust the magnitude of the flexible restraint force in real time.

2. The AGV robot palletizing system for docking milk filling lines and storage lines according to claim 1, characterized in that: The vehicle condition monitoring module includes at least one of an inertial measurement unit and a drive encoder, and is used to output the AGV's operating status data, including at least: longitudinal acceleration of the vehicle body, lateral acceleration of the vehicle body, angular velocity of the vehicle body about the vertical axis, and vehicle speed. The operating status data is sent to the processing module according to the sampling period; The processing module determines the target airbag pressure or target pressure change rate of the airbag-type side-hug module based on the velocity, acceleration, and / or angular velocity data.

3. The AGV robot palletizing system for docking milk filling lines and storage lines according to claim 1, characterized in that: The guide rail AGV is also equipped with a vision monitoring module, including an industrial camera and / or a depth camera, which is installed on the towing platform to collect the posture information of the entire stack of goods and output tilt state data; wherein, the tilt state data includes at least the tilt angle and tilt direction of the entire stack of goods relative to the vertical direction.

4. The AGV robot palletizing system for docking milk filling lines and storage lines according to claim 3, characterized in that: The processing module is used to convert the cargo tilt state data output by the visual monitoring module into a static pressure compensation component, and the motion state data output by the vehicle condition monitoring module into a dynamic pressure correction component. The target pressure value is generated by using the static pressure compensation component as the reference pressure component, and the dynamic pressure correction component is superimposed in real time during the operation of the guide rail AGV to update the target pressure value; and an upper pressure limit and a lower pressure limit are set for the target pressure value.

5. The AGV robot palletizing system for docking milk filling lines and storage lines according to claim 1, characterized in that: The processing module is used to generate target pressure values ​​for the left and right sides of the two symmetrically arranged airbag side-holding modules, and to determine the differential compensation amount, so that the target pressure values ​​for the left and right sides are increased or decreased by the differential compensation amount based on the target pressure values.

6. The AGV robot palletizing system for docking milk filling lines and storage lines according to claim 1, characterized in that: Each airbag-type side-hug module also includes a pressure sensor for detecting the actual airbag pressure and feeding it back to the processing module; The processing module controls the pressure regulating valve to inflate or deflate the airbag based on the pressure deviation between the target pressure value and the actual airbag pressure, and sets an upper limit for the pressure change rate of the target pressure value so that the airbag pressure is adjusted to change continuously.

7. An AGV robot palletizing method for docking milk filling lines and storage lines, based on the AGV robot palletizing system for docking milk filling lines and storage lines as described in any one of claims 1-6, characterized in that, Includes the following steps: Step S1: In the static stage before the start of the guide rail AGV, the posture information of the entire stack of goods is collected by the vision monitoring module. The processing module calculates the initial tilt angle and tilt direction based on the posture information and converts them into static pressure compensation components, which serve as the reference pressure value of the airbag side-holding module. Step S2: The vehicle condition monitoring module collects real-time operating status data and sends it to the processing module. The processing module calculates the dynamic pressure correction component based on acceleration and speed changes. Step S3: The processing module performs real-time superposition calculation on the static pressure compensation component and the dynamic pressure correction component to generate a target pressure value, and sends a control command to the pressure regulating valve of the airbag side clamping module to make the airbag pressure track the target pressure value, thereby achieving flexible constraint on the entire stack of goods.

8. The AGV robot palletizing method for docking milk filling lines and storage lines according to claim 7, characterized in that: In step S1, the static pressure compensation component acts differentially on two sets of symmetrically arranged airbag side-hug modules, so that the airbags on the side closer to the tilt direction establish a higher reference pressure, and the airbags on the side away from the tilt direction establish a relatively lower reference pressure. The processing module performs differential correction on the two airbags based on the lateral acceleration and / or angular velocity directions in the operating status data to form a differential flexible constraint force that counteracts the tilting trend.

9. The AGV robot palletizing method for docking milk filling lines and storage lines according to claim 7, characterized in that: In step S3, the processing module sets a lower pressure limit and an upper pressure limit for the target pressure value, and sets an upper limit for the pressure change rate, so that the target pressure value changes continuously under the conditions of amplitude and speed limit; wherein, the static pressure compensation component is updated according to the visual update cycle, and the dynamic pressure correction component is updated according to the vehicle condition update cycle.

10. The AGV robot palletizing method for docking milk filling lines and storage lines according to claim 7, characterized in that: When an anomaly criteria are met, a safety policy is triggered. The anomaly criteria include at least: the tilt angle exceeds the tilt threshold, the actual airbag pressure cannot track the target pressure value within a preset time, or the operating status data exceeds the safety threshold. The safety strategy includes at least: switching the target pressure value to the reinforcement pressure and / or controlling the airbag side-hugging module to depressurize to a safe pressure, and controlling the guide rail AGV to enter a speed-limited operation or stop operation state.

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