Mobile picking robot and method of changing a mobile picking robot end effector

Abstract

This invention discloses a mobile picking robot and a method for replacing the end effector of the mobile picking robot, relating to the field of intelligent warehousing and logistics automation technology. The mobile picking robot includes: a mobile chassis for autonomous movement within a warehouse; a lifting module mounted on the mobile chassis; a robotic arm mounted on the movable end of the lifting module; a quick-change master tray fixedly connected to the end of the robotic arm; at least two tool holders fixedly mounted on the mobile chassis or a frame above the mobile chassis, each tool holder storing at least one end effector with a quick-change tool tray, and different tool holders storing end effectors of different types or specifications; and a controller communicatively connected to the mobile chassis, lifting module, robotic arm, and quick-change master tray. This implementation can reduce unnecessary round trips, improve overall picking efficiency, and significantly reduce the time overhead associated with each end effector replacement.

Description

Technical Field

[0001] This invention relates to the field of intelligent warehousing and logistics automation technology, and in particular to a mobile picking robot and a method for replacing the end effector of the mobile picking robot. Background Technology

[0002] With the rapid development of e-commerce, retail, and third-party logistics industries, the variety of stock keeping units (SKUs) in warehouses has increased dramatically, and their shapes, sizes, and materials have also shown significant differences. To complete diverse picking tasks, mobile picking robots typically need to be equipped with different types of end effectors, such as vacuum suction cup end effectors for regular objects like cardboard boxes, gripper-type end effectors for bagged or small boxed objects, and flexible grippers for soft packaging or irregularly shaped items.

[0003] In existing technologies, mobile picking robots mainly employ the following solutions when handling multi-SKU orders: Firstly, to simplify the system structure, some robots are only equipped with one type of end effector. However, this approach cannot be compatible with multiple types of SKUs, resulting in a severely limited picking range.

[0004] Secondly, multiple different types of tool heads are fixedly installed at the end of the robotic arm, allowing the use of different tools by switching the arm's posture. This approach makes the robotic arm structure more complex and increases its weight, affecting the robot's mobility and operational safety, especially posing a risk of interference in narrow shelving aisles.

[0005] Thirdly, a more common approach is to set up one or more fixed tool-changing stations in the warehouse. When a robot needs to change its end effector, it must interrupt the current picking operation, travel to the fixed station to complete the disassembly and replacement, and then return to the shelf to continue the operation. The drawbacks of this approach are twofold: firstly, the frequent back-and-forth movement of the robot between the shelf and the fixed station generates a significant amount of non-productive travel distance; secondly, for orders containing multiple SKUs, the accumulated time cost of multiple changes is substantial, severely restricting overall picking efficiency. Furthermore, the location of the fixed station limits the flexibility of warehouse layout.

[0006] In summary, how to enable mobile picking robots to automatically and quickly change to the appropriate end effector based on the type of SKU to be picked without returning to a fixed location, so as to efficiently complete picking tasks in multi-SKU scenarios, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0007] In view of this, embodiments of the present invention provide a mobile picking robot and a method for replacing the end effector of the mobile picking robot, which can replace the end effector at any suitable position in the robot picking path, reduce unnecessary round trips, and improve overall picking efficiency; it significantly reduces the time cost of replacing the end effector once, and is more efficient than the solution that requires returning to a fixed point for replacement.

[0008] To achieve the above objectives, according to one aspect of the present invention, a mobile picking robot is provided, comprising: Mobile chassis for autonomous movement within warehouses; The lifting module is installed on the mobile chassis; A robotic arm is mounted on the movable end of the lifting module; The quick-change master plate is fixedly connected to the end of the robotic arm; At least two tool holders are fixedly mounted on the mobile chassis or on a frame above the mobile chassis. Each tool holder is used to store at least one end effector with a quick-change tool tray, and different tool holders are used to store end effectors of different types or specifications. The controller is communicatively connected to the mobile chassis, the lifting module, the robotic arm, and the quick-change master panel.

[0009] Optionally, the controller is configured to: when it is necessary to replace the first end effector currently installed on the quick-change master disk with a second end effector stored on the target tool holder, control the robotic arm to move the quick-change master disk to the tool holder storing the first end effector, control the quick-change master disk to unlock to remove the first end effector; then control the robotic arm to move the quick-change master disk to the target tool holder storing the second end effector, control the quick-change master disk to dock and lock with the quick-change tool disk of the second end effector.

[0010] Optionally, the controller is further configured to control the robotic arm to perform the unloading action and / or docking and locking action of the end effector during the movement of the mobile chassis or when the mobile chassis is paused.

[0011] Optionally, the tool holder includes a tool positioning seat, the structure of which matches the shape of the stored end effector, for stably supporting and holding the end effector during the movement of the mobile chassis.

[0012] Optionally, the quick-change master disc and the quick-change tool disc are provided with a cooperating mechanical locking structure, an electrical signal interface and an air circuit interface.

[0013] Optionally, the quick-change tool disk is equipped with an encoding chip or RFID tag, and the quick-change main disk is equipped with a reading module for reading the encoding chip or RFID tag. The controller identifies the type of the currently connected end effector based on the reading result of the reading module.

[0014] Optionally, it also includes an auxiliary vision sensor, disposed near the tool holder or on the robotic arm, for assisting in the alignment of the quick-change master disc and the quick-change tool disc.

[0015] Optionally, the tool holders are of two or three types, used to store vacuum suction cup type end effectors, gripper type end effectors and flexible gripper type end effectors, respectively.

[0016] Optionally, the tool holder is arranged along the lifting column, the edge of the chassis, or the periphery of the material box of the mobile chassis, and when the end effector is stored on the tool holder, the end effector does not exceed the horizontal projection outline of the mobile chassis.

[0017] According to another aspect of the present invention, a method for replacing the end effector of a mobile picking robot is provided, comprising: Receive picking tasks, wherein the picking tasks include the storage location address and item type of one or more items to be picked; Based on the preset mapping relationship between item type and end effector type, determine the type of end effector required for picking each item to be picked, and plan the picking path and the replacement position of the end effector in combination with the storage location address of each item to be picked. Before picking the first item to be picked, if the current quick-change master panel does not have an end effector installed, the control robot arm picks up and installs the target end effector from the tool tray containing the end effector type required for the first item to be picked. During the process of traveling along the picking path and picking multiple items to be picked in sequence, in response to reaching the replacement position of the end effector, if the type of end effector installed on the current quick-change master plate is inconsistent with the type of end effector required for the next item to be picked, the robotic arm is controlled to send the current end effector back to the corresponding tool tray and the quick-change master plate is controlled to unlock and separate. Then, the robotic arm is controlled to move to the tool tray where the target end effector is located, and the quick-change master plate is controlled to dock and lock with the quick-change tool tray of the target end effector to install the target end effector.

[0018] Optionally, the replacement location of the end effector is a point on the path along which the mobile chassis travels from one shelf storage location to the next.

[0019] Optionally, the replacement operation of the end effector is performed while the mobile chassis is in motion.

[0020] Optionally, the picking path and the replacement location of the end effector are planned in combination with the storage location address of each item to be picked, including: planning the picking path in combination with the storage location address of each item to be picked, and aggregating consecutive items to be picked that require the same type of end effector into a picking group to determine the replacement location of the end effector.

[0021] One embodiment of the above invention has the following advantages or beneficial effects: By setting a tool holder on the mobile chassis and configuring a quick-change master tray and a quick-change tool tray at the end of the robotic arm, the replacement location of the end effector is no longer limited to a fixed workstation. Replacement can be achieved at any suitable location in the robot's picking path, reducing unnecessary back-and-forth trips and improving overall picking efficiency. Using a mechanical quick-change structure and standardized electrical or pneumatic interfaces, the unloading and attaching actions can be completed within seconds and can be superimposed on the robot's movement time, significantly reducing the time overhead of a single end effector replacement. This is more efficient than solutions that require returning to a fixed location for replacement. Furthermore, the quick-change master tray provides a universal interface that can connect to various types of quick-change tool trays and end effectors, exhibiting high compatibility with end effectors of different shapes, weights, and functions, facilitating future expansion with new gripping tools. During the mobile picking robot's movement and picking process, the appropriate end effector is automatically selected and quickly replaced according to the type of item to be picked; it supports picking multiple items in a single task, completing multiple end effector switches without interrupting the picking process or returning to a fixed replacement point, thereby significantly improving picking efficiency. Meanwhile, the mobile picking robot is compact, safe, and reliable, making it suitable for operation in narrow spaces such as shelf aisles.

[0022] The further effects of the aforementioned unconventional alternative methods will be explained below in conjunction with specific implementation methods. Attached Figure Description

[0023] The accompanying drawings are provided to better understand the invention and are not intended to unduly limit the scope of the invention. Wherein: Figure 1 This is a schematic diagram of a mobile picking robot performing a picking operation according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the mobile picking robot according to an embodiment of the present invention; Figure 3 This is a schematic diagram illustrating the connection relationship between the robotic arm and the quick-change master plate and quick-change tool plate according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the specific structure of a tool holder according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the specific structure of a tool holder according to another embodiment of the present invention; Figure 6 This is a schematic diagram of the main steps of a method for replacing the end effector of a mobile picking robot according to an embodiment of the present invention.

[0024] The attached figures are labeled as follows: 1-Mobile chassis; 2-Lifting module; 3-Robotic arm; 4-Quick-change main plate; 5-Tool holder; 6-Quick-change tool plate; 7-End effector; 8-Tool positioning seat. Detailed Implementation

[0025] The following description, in conjunction with the accompanying drawings, illustrates exemplary embodiments of the present invention, including various details to aid understanding. These details should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0026] The purpose of this invention is to provide a mobile picking robot and a method for replacing the end effector of the mobile picking robot, to solve the problems of existing end effectors having a single type, difficulty in compatibility with multiple items, and the need to return to a fixed workstation for replacement, resulting in long round trip distances and low efficiency. The invention achieves the following objectives: during the movement and picking process of the mobile picking robot, it automatically selects and quickly replaces the appropriate end effector according to the type of item to be picked; it supports picking multiple items in a single task, completing multiple end effector switches without interrupting the picking process or returning to a fixed replacement point, thereby significantly improving picking efficiency. Furthermore, this mobile picking robot has a compact structure, is safe and reliable, and is suitable for operation in narrow spaces such as aisle shelves.

[0027] Figure 1 This is a schematic diagram illustrating a scenario where a mobile picking robot performs a picking operation according to an embodiment of the present invention. Figure 1 As shown, in an embodiment of the present invention, the shelf contains multiple storage boxes, which may hold square items, round items, or other irregularly shaped items, etc. The mobile picking robot of this embodiment allows for the replacement of the end effector during picking operations, facilitating the picking of items of various shapes.

[0028] Figure 2 This is a schematic diagram of the structure of a mobile picking robot according to an embodiment of the present invention. Figure 2 As shown, the mobile picking robot of this invention mainly includes: a mobile chassis 1, a lifting module 2, a robotic arm 3, a quick-change main tray 4, at least two tool holders 5, and a controller.

[0029] The mobile chassis 1 is used for autonomous movement within the warehouse. For example, it is a commonly used autonomous mobile robot, which may have several parts such as drive wheels, driven wheels, sensors, and control systems, which will not be described in detail here.

[0030] Lifting module 2 is mounted on mobile chassis 1. Lifting module 2 is a vertical linear mechanism mounted on mobile chassis 1, providing the height adjustment capability of the robotic arm 3, enabling the robotic arm 3 to cover storage boxes of different shelf heights.

[0031] The robotic arm 3 is installed at the movable end of the lifting module 2 and can have multiple rotational degrees of freedom.

[0032] The quick-change master plate 4 is fixedly connected to the end of the robotic arm 3. As a universal interface, the quick-change master plate 4 can quickly connect or disconnect with different types of end effectors 7 through mechanical quick-change mechanisms and electrical / pneumatic interfaces, realizing the rapid replacement of end effectors.

[0033] At least two tool holders 5 are fixedly mounted on the mobile chassis 1 or on a frame above the mobile chassis 1. Each tool holder 5 is used to store at least one end effector 7 with a quick-change tool tray 6, and different tool holders 5 are used to store end effectors 7 of different types or specifications. The quick-change tool tray 6 is connected to different types of end effectors 7 and can be mechanically locked and connected to the quick-change main tray 4 via electrical signals and pneumatic circuits.

[0034] The controller is communicatively connected to the mobile chassis 1, lifting module 2, robotic arm 3, and quick-change main tray 4. Specifically, the robot's controller is electrically connected to the drive mechanisms of the robotic arm 3, lifting module 2, quick-change main tray 4, and mobile chassis 1. It can communicate bidirectionally with the warehouse management system, receive picking tasks and type information of items to be picked (e.g., SKUs to be picked), and transmit the execution status back. Based on the mapping table between SKU type and end effector type, the controller automatically selects the appropriate end effector 7 and plans the picking path and the timing of the quick change action of the end effector 7.

[0035] According to an embodiment of the present invention, the controller can be configured to: when it is necessary to replace the first end effector 7 currently installed on the quick-change master tray 4 with the second end effector 7 stored on the target tool tray 5, control the robotic arm 3 to move the quick-change master tray 4 to the tool tray 5 where the first end effector 7 is stored, and control the quick-change master tray 4 to unlock to remove the first end effector 7; subsequently, control the robotic arm 3 to move the quick-change master tray 4 to the target tool tray 5 where the second end effector 7 is stored, and control the quick-change master tray 4 to dock and lock with the quick-change tool tray 6 of the second end effector 7. Based on the type information of the SKU to be picked issued by the warehouse management system, the robot controller automatically decides and controls the robotic arm 3 to complete the detachment and attachment of the end effector 7 at the tool tray 5 position during travel or midway through the picking path, realizing "moving and changing tools simultaneously".

[0036] According to one embodiment of the present invention, the controller may also be configured to control the robotic arm 3 to perform the unloading action and / or docking and locking action of the end effector 7 during the movement of the mobile chassis 1 or when the mobile chassis 1 is paused.

[0037] According to one embodiment of the present invention, the tool holder 5 includes a tool positioning seat 8. The structure of the tool positioning seat 8 matches the shape of the stored end effector 7, and is used to stably support and hold the end effector 7 during the movement of the mobile chassis 1. The tool holder 5 is fixed to the mobile chassis 1 or its upper column, and may be an aluminum profile frame structure. Each tool holder 5 is provided with at least one tool positioning seat 8 for suspending or inserting a certain type of end effector 7. The structural shape of the tool positioning seat 8 matches the shape of the end effector 7, which can stably support the end effector 7 during robot movement and prevent shaking or falling off. Figure 2 Two vertical profile supports can be set on one side of the mobile chassis 1 as tool holders 5, which can respectively hang the "suction cup end effector" and the "gripper end effector". When the robot is moving, the end effector 7 is located within the outline of the mobile chassis 1 to avoid interference with the outside world.

[0038] Figure 4 This is a schematic diagram of the specific structure of a tool holder according to an embodiment of the present invention. Figure 4 As shown, the tool holder 5 can be fixed to the mobile chassis 1 via a fixed frame, and has a tool positioning seat 8 on it. An end effector 7 (suction cup end effector) with a quick-change tool tray 6 is suspended or inserted into the tool positioning seat 8, and the structural shape of the tool positioning seat 8 can match the shape of the end effector 7 to stably support it. The tool positioning seat 8 can be connected to the quick-change tool tray 6 via electromagnetic adsorption to facilitate the replacement of the end effector 7.

[0039] Figure 5This is a schematic diagram of the specific structure of a tool holder according to another embodiment of the present invention. Figure 5 As shown, an end effector 7 (gripper end effector) with a quick-change tool disc 6 is suspended or inserted on the tool positioning seat 8, and the structural shape of the tool positioning seat 8 can match the shape of the end effector 7 to stably support the end effector 7.

[0040] According to one embodiment of the present invention, a mechanical locking structure, an electrical signal interface, and an air circuit interface are provided between the quick-change main plate 4 and the quick-change tool plate 6. The mechanical locking structure includes, for example, a jaw and conical positioning structure, a ball-locking pin mechanism, etc.

[0041] Figure 3 This is a schematic diagram illustrating the connection relationship between the robotic arm 3 and the quick-change master plate and quick-change tool plate according to an embodiment of the present invention. The robotic arm 3 can be mounted on the slider or rotating base of the lifting module 2 and has multiple rotational degrees of freedom. A quick-change master plate 4 is provided at the end of the robotic arm 3, and the quick-change master plate 4 is fixedly connected to the flange of the robotic arm 3. The front end of the quick-change master plate 4 is provided with a mechanical locking structure (such as a claw and conical positioning structure, ball lock pin mechanism, etc.) that cooperates with the quick-change tool plate 6, as well as an air circuit interface and an electrical signal interface. The quick-change master plate 4 is internally configured with a drive actuator (such as an electromagnetic lock, cylinder, spring locking structure, etc.) for controlling the locking / releasing with the quick-change tool plate 6.

[0042] Each end effector 7 (e.g., vacuum suction cup tool, two-finger gripper, flexible gripper, etc.) is connected to the quick-change master plate 4 via a quick-change tool tray 6. The rear end of the quick-change tool tray 6 has a locking flange or plug-in structure that mates with the quick-change master plate 4, and is equipped with corresponding electrical interfaces and pneumatic passages for plug-and-play functionality. The front end of the quick-change tool tray 6 is connected to the specific end effector 7 via a mechanical connection, ensuring that the installation and removal of each end effector 7 does not affect the structure of the quick-change master plate 4.

[0043] According to one embodiment of the present invention, the quick-change tool tray 6 is equipped with an coded chip or an RFID (Radio Frequency Identification) tag, and the quick-change main tray 4 is equipped with a reading module for reading the coded chip or RFID tag. The controller identifies the type of the currently connected end effector based on the reading result of the reading module. After the quick-change main tray 4 reads the coded chip or RFID tag, it can identify the type of the currently connected end effector, causing the controller to automatically load the corresponding torque, speed, safety, and other parameters. When an unlocking failure or identification abnormality is detected, high-speed movement of the robotic arm 3 is prohibited to prevent the end effector 7 from falling off.

[0044] According to one embodiment of the present invention, the mobile picking robot may further include an auxiliary vision sensor, disposed near the tool carrier 5 or on the robotic arm 3, for assisting in the alignment of the quick-change master tray 4 and the quick-change tool tray 6. Placing a small camera or sensor near the tool carrier 5 can assist the robotic arm 3 in accurately aligning the quick-change tool tray 6, improving docking reliability. Furthermore, the quick-change master tray 4 and the quick-change tool tray 6 may also employ a mechanically guided conical or inclined structure, allowing for successful insertion even with a certain degree of positional error.

[0045] According to one embodiment of the present invention, the number of tool holders 5 is two or three, respectively used to store vacuum suction cup type end effectors, gripper type end effectors, and flexible gripper type end effectors. In specific implementation, the number of tool holders 5 can be determined according to the number of end effectors 7 that need to be stored.

[0046] According to one embodiment of the present invention, the tool holder 5 is arranged along the lifting column, the edge of the chassis 1, or the periphery of the material box, and when the end effector 7 is stored on the tool holder 5, the end effector 7 does not exceed the horizontal projection outline of the mobile chassis 1. Additionally, the tool holder 5 can also be arranged in the form of a ring-shaped tool magazine to accommodate different robot structures.

[0047] Figure 6 This is a schematic diagram illustrating the main steps of a method for replacing the end effector of a mobile picking robot according to an embodiment of the present invention. Figure 6 As shown, the method for replacing the end effector of the mobile picking robot in this embodiment of the invention mainly includes the following steps S601 to S604.

[0048] Step S601: Receive picking task. The picking task includes the storage location address and item type of one or more items to be picked.

[0049] After receiving order information, the warehouse management system breaks down the order into one or more picking tasks. Each task includes multiple SKUs to be picked, their quantities, storage locations, and SKU type information (such as "boxed", "bagged", "soft-packed", "irregularly shaped items", etc.). The warehouse management system then dispatches the picking tasks to a mobile picking robot.

[0050] Step S602: Based on the preset mapping relationship between item type and end effector type, determine the type of end effector required for picking each item to be picked, and plan the picking path and the replacement position of the end effector 7 in combination with the storage location address of each item to be picked. After receiving the picking task, the controller of the mobile picking robot determines the type of end effector corresponding to each SKU to be picked based on the pre-established mapping relationship between SKU type and end effector type. For example, the end effector type corresponding to boxed items is a vacuum suction cup; the end effector type corresponding to bagged food and small boxed items is a gripper; the end effector type corresponding to flexible items is a flexible gripper, etc.

[0051] The mobile picking robot's controller generates a picking path that comprehensively considers travel distance, tool change (i.e., changing the end effector 7), and tool change location based on the storage location of all SKUs to be picked and their corresponding end effector types. Unlike the traditional "return to a fixed point for tool change", this invention utilizes a tool carrier 5 mounted on the mobile chassis 1, allowing the end effector 7 to be changed at any time during the robot's picking task.

[0052] According to one embodiment of the present invention, the end effector 7 is replaced at a point on the path of the mobile chassis 1 traveling from one shelf location to the next. Specifically, the controller preferably schedules the end effector replacement action at the following stages: while the mobile chassis 1 is traveling from one shelf location to the next; or just after the robot has completed all picking operations for a certain type of SKU and is about to begin picking the next type of SKU. In this way, the time for replacing the end effector 7 can overlap with the travel time, reducing additional downtime.

[0053] According to one embodiment of the present invention, planning the picking path and the replacement location of the end effector 7 by combining the storage location address of each item to be picked can specifically include: planning the picking path by combining the storage location address of each item to be picked, and aggregating consecutive items to be picked that require the same type of end effector 7 into a picking group to determine the replacement location of the end effector 7. When multiple consecutive SKUs require the same type of end effector 7, these multiple consecutive SKUs are aggregating into a picking group, eliminating the need to repeatedly replace the end effector 7, thereby reducing the number of times the end effector 7 is replaced and reducing picking operation time.

[0054] Step S603: Before picking the first item to be picked, if the current quick-change master tray 4 is not equipped with an end effector 7, the control robot arm 3 picks up and installs the target end effector 7 from the tool tray 5 which is the type of end effector 7 required to store the first item to be picked.

[0055] In the specific implementation process, before picking the first SKU, the controller selects the required end effector 7 based on the type of the first SKU. If no end effector 7 is installed on the quick-change master tray 4 at this time, the robotic arm 3 first moves to the corresponding tool holder 5 and picks up the required end effector 7 from the tool holder 5. If an end effector 7 that does not match the type of the first SKU is already installed on the quick-change master tray 4, the unloading action is performed first, and then the target end effector 7 is installed. Here, the implementation process of performing the unloading action first and then installing the target end effector 7 is detailed in the end effector 7 replacement process described in step S604.

[0056] Step S604: During the process of traveling along the picking path and picking multiple items to be picked in sequence, in response to reaching the replacement position of the end effector 7, if the type of end effector installed on the current quick-change master plate 4 is inconsistent with the type of end effector required for the next item to be picked, the robotic arm 3 is controlled to send the current end effector 7 back to the corresponding tool tray 5 and the quick-change master plate 4 is controlled to unlock and separate. Then, the robotic arm 3 is controlled to move to the tool tray 5 where the target end effector 7 is located, and the quick-change master plate 4 is controlled to dock and lock with the quick-change tool tray 6 of the target end effector 7 to install the target end effector 7.

[0057] When replacing the end effector 7, the current end effector 7 must first be removed before the target end effector 7 can be attached.

[0058] Specifically, when the current end effector 7 is removed, the robotic arm 3 drives the quick-change master disk 4 to move to the corresponding empty position in the tool holder 5 and inserts the current end effector 7 into the support seat of the empty position; the quick-change master disk 4 is controlled to perform an unlocking action (e.g., drive the locking pin to retract and release the chuck), releasing the locking connection with the quick-change tool disk 6; the robotic arm 3 slowly retracts, separating the quick-change master disk 4 from the end effector 7, and the end effector 7 is supported by the tool holder 5 to maintain its original position.

[0059] When attaching the target end effector 7, the robotic arm 3 moves to the tool tray 5 containing the end effector 7, based on its type. Guided by visual recognition or a preset path, the quick-change master plate 4 aligns with the quick-change tool tray 6 on the target end effector 7 and advances along its axis until the mechanical interfaces are fully engaged. Then, the quick-change master plate 4 performs a locking action (locking pin extension, jaw closure, etc.) to complete mechanical locking and electrical / pneumatic connection. The controller performs a simple handshake check, such as reading the unique ID of the end effector 7 or detecting signal continuity. After confirming successful connection of the replaced end effector 7, it is reinstated for the picking task.

[0060] According to one embodiment of the present invention, the replacement operation of the end effector 7 is performed while the mobile chassis 1 is in a moving state. The replacement operation of the end effector 7 refers to first removing the current end effector 7 and then attaching the target end effector 7. The entire process of removing and attaching the end effector 7 can be performed while the mobile chassis 1 is moving slowly, or it can be performed when the robot makes a brief stop, without requiring a special return to a fixed replacement station.

[0061] According to one embodiment of the present invention, during the entire order picking process, as the robot sequentially moves to different storage locations to pick different types of SKUs, the controller monitors in real time the current end effector type and the end effector type required for the next SKU to be picked. When the two do not match, a "tool carrier 5 node" is inserted into the path of the robot to the next storage location, guiding the robotic arm 3 to perform the aforementioned end effector 7 replacement operation at that node. After the replacement is completed, the robot continues to the target storage location along the original path and uses the new end effector 7 to perform the picking operation. When multiple consecutive SKUs to be picked require the use of the same type of end effector 7, there is no need to repeatedly change the end effector 7, thereby reducing the number of tool changes.

[0062] By employing the aforementioned end effector replacement strategy, this invention achieves dynamic automatic tool changing during mobile picking, combined with the order SKU sequence, significantly reducing non-operation time.

[0063] According to the technical solution of this invention, by setting a tool carrier on a mobile chassis and configuring a quick-change master tray and a quick-change tool tray at the end of the robotic arm, the replacement location of the end effector is no longer limited to a fixed workstation. Replacement can be achieved at any suitable location along the robot's picking path, reducing unnecessary back-and-forth trips and improving overall picking efficiency. Employing a mechanical quick-change structure and standardized electrical or pneumatic interfaces, the unloading and attaching actions can be completed within seconds and can be superimposed on the robot's movement time, significantly reducing the time overhead of a single end effector replacement. This is more efficient than solutions that require returning to a fixed location for replacement. Furthermore, the quick-change master tray provides a universal interface, allowing connection to various types of quick-change tool trays and end effectors, exhibiting high compatibility with end effectors of different shapes, weights, and functions, facilitating future expansion with new gripping tools. During the mobile picking robot's movement and picking process, the robot automatically selects and quickly replaces the appropriate end effector based on the type of item to be picked. It supports picking multiple items in a single task, completing multiple end effector switches without interrupting the picking process or returning to a fixed replacement point, thereby significantly improving picking efficiency. Meanwhile, the mobile picking robot is compact, safe, and reliable, making it suitable for operation in narrow spaces such as shelf aisles.

[0064] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can occur depending on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A mobile picking robot, characterized in that, include: Mobile chassis (1) for autonomous movement within a warehouse; The lifting module (2) is installed on the mobile chassis (1); A robotic arm (3) is installed at the movable end of the lifting module (2); The quick-change master plate (4) is fixedly connected to the end of the robotic arm (3); At least two tool holders (5) are fixedly mounted on the mobile chassis (1) or on the frame above the mobile chassis (1). Each tool holder (5) is used to store at least one end effector (7) with a quick-change tool tray (6), and different tool holders (5) are used to store end effectors (7) of different types or specifications. The controller is communicatively connected to the mobile chassis (1), the lifting module (2), the robotic arm (3), and the quick-change master plate (4).

2. The mobile picking robot according to claim 1, characterized in that, The controller is configured to: When it is necessary to replace the first end effector (7) currently installed on the quick-change master disk (4) with the second end effector (7) stored on the target tool holder (5), control the robotic arm (3) to move the quick-change master disk (4) to the tool holder (5) where the first end effector (7) is stored, and control the quick-change master disk (4) to unlock to remove the first end effector (7). Then, the robotic arm (3) is controlled to move the quick-change master disk (4) to the target tool holder (5) where the second end effector (7) is stored, and the quick-change master disk (4) is controlled to dock and lock with the quick-change tool disk (6) of the second end effector (7).

3. The mobile picking robot according to claim 2, characterized in that, The controller is also configured to: During the movement of the mobile chassis (1) or when the mobile chassis (1) is paused, the robotic arm (3) is controlled to perform the unloading action and / or docking and locking action of the end effector (7).

4. The mobile picking robot according to claim 1, characterized in that, The tool holder (5) includes a tool positioning seat (8), the structure of which matches the shape of the end effector (7) stored thereon, and is used to stably support and hold the end effector (7) during the movement of the mobile chassis (1).

5. The mobile picking robot according to claim 1, characterized in that, The quick-change master plate (4) and the quick-change tool plate (6) are provided with a mechanical locking structure, an electrical signal interface and an air circuit interface that cooperate with each other.

6. The mobile picking robot according to claim 5, characterized in that, The quick-change tool disk (6) is equipped with an encoding chip or RFID tag, and the quick-change main disk (4) is equipped with a reading module for reading the encoding chip or RFID tag. The controller identifies the type of the currently connected end effector based on the reading result of the reading module.

7. The mobile picking robot according to claim 1, characterized in that, It also includes an auxiliary vision sensor, which is located near the tool holder (5) or on the robotic arm (3) to assist in the alignment of the quick-change master plate (4) and the quick-change tool plate (6).

8. The mobile picking robot according to claim 1, characterized in that, The tool holders (5) are in the form of two or three, which are used to store vacuum suction cup end effectors (7), gripper end effectors (7) and flexible gripper end effectors (7), respectively.

9. The mobile picking robot according to claim 1, characterized in that, The tool holder (5) is arranged along the lifting column, the edge of the chassis or the periphery of the material box of the mobile chassis (1), and when the end effector (7) is stored on the tool holder (5), the end effector (7) does not exceed the horizontal projection outline of the mobile chassis (1).

10. A method for replacing the end effector of a mobile picking robot based on any one of claims 1 to 9, characterized in that, include: Receive picking tasks, wherein the picking tasks include the storage location address and item type of one or more items to be picked; Based on the preset mapping relationship between item type and end effector type, determine the type of end effector required for picking each item to be picked, and plan the picking path and the replacement position of the end effector (7) in combination with the storage location address of each item to be picked; Before picking the first item to be picked, if the current quick-change master tray (4) is not equipped with an end effector (7), the control robot arm (3) picks up and installs the target end effector (7) from the tool tray (5) of the end effector (7) of the type of end effector required to store the first item to be picked. During the process of traveling along the picking path and picking multiple items to be picked in sequence, in response to the arrival at the replacement position of the end effector (7), if the type of end effector installed on the current quick-change master plate (4) is inconsistent with the type of end effector required for the next item to be picked, the control robot arm (3) sends the current end effector (7) back to the corresponding tool holder (5) and controls the quick-change master plate (4) to unlock and separate. Then, the control robot arm (3) moves to the tool holder (5) where the target end effector (7) is located, controls the quick-change master plate (4) to dock with the quick-change tool plate (6) of the target end effector (7) and lock it to install the target end effector (7).

11. The replacement method according to claim 10, characterized in that, The replacement position of the end effector (7) is a point on the path of the mobile chassis (1) traveling from one shelf storage location to the next shelf storage location.

12. The replacement method according to claim 10, characterized in that, The replacement operation of the end effector (7) is performed while the mobile chassis (1) is in a driving state.

13. The replacement method according to claim 10, characterized in that, The picking path and the replacement location of the end effector (7) are planned based on the storage location address of each item to be picked, including: The picking path is planned by combining the storage location address of each item to be picked, and consecutive items to be picked that require the same type of end effector (7) are grouped into a picking group to determine the replacement location of the end effector (7).

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