GridBot

Abstract

An AGV (50) configured for grid navigation and a corresponding transport method are disclosed. The AGV comprises: a plurality of AGVs (10) formed by at least first and second groups of AGVs (10); a travel surface (25) within which the AGVs (10) move along a grid structure (24), wherein the AGVs (10) of the first group (54-1) may only be moved along a first base vector (V1) and wherein the AGVs (10) of the second group (54-2) may only be moved along the second base vector (V2) spanning the travel surface (25); and a controller (18; 52) configured to plan a route (28) along the grid (24) between a predetermined starting point (30) and a predetermined destination point (32), so that selected ones of the AGVs (10) transport a transport item (28) from the starting point (30) to the destination point (32) by transferring it between the selected AGVs (10).

Description

[0001] The present disclosure relates to a driverless transport system configured to perform grid navigation, particularly in an intralogistics system, such as a storage and / or order-picking system. Furthermore, the present disclosure relates to a method for transporting a transport item in such a system.

[0002] Automated guided vehicle systems (AGVs), consisting of automated guided vehicles (AGVs), automated guided vehicles (AGVs), or autonomous mobile robots (AMRs), are increasingly important components of modern intralogistics and production processes. These systems offer various technological advantages and contribute to increased efficiency. These systems represent a significant advance in the automation of material flow.

[0003] An AGV is an automated vehicle that transports goods, such as materials, products, warehouse goods (including load carriers), or other loads, within a production facility, (picking) warehouse, or other operational site without human intervention. These vehicles are typically equipped with various technologies such as sensors, navigation systems, and sometimes artificial intelligence to ensure safe and efficient movement through their environment. AGVs are a core component of modern automated intralogistics systems designed to increase efficiency and reduce human workload.

[0004] AGVs can be configured for a wide range of tasks, from simple material transport to more complex tasks such as workpiece handling or palletizing. Solutions are already available that are specifically tailored to the needs of modern order picking and offer the flexibility to change routes quickly and easily. Modern AGVs utilize advanced technologies such as real-time tracking, navigation technologies, and energy efficiency technologies for this purpose. Implementing AGVs also involves careful route planning.

[0005] Furthermore, there is a tendency for AGVs to transfer the goods they are transporting, particularly on their top surfaces, to another entity, such as another vehicle or a transfer station, using inertia. This is referred to as an inertia-based transfer of the goods. The inertia-based transfer of goods is described as an example in document DE 10 2021 118 923 A1.

[0006] Document EP 3 180 275 B1 describes a fleet of vehicles navigated by a master controller. The master controller is referred to as the "fleet manager" in this document, and transport order processing is communicated from a (separate) material flow computer (MFC) to the fleet manager. A map of a driving level is also stored in the vehicles. EP 3 180 275 B1 also describes a conventional configuration process, the communication between the vehicles and the fleet manager, and the data exchanged.

[0007] According to its title, the document DE 10 2014 111 394 A1 concerns a storage and picking system and method for the optimized storage and retrieval of articles.

[0008] According to its title, document EP 4 254 123 A2 relates to a method and a system for autonomously controlling movements of container handling vehicles in an automated storage and retrieval system.

[0009] According to its title, document US 2023 / 0 365 335 A1 concerns an automated storage and retrieval system with multi-directional vehicles.

[0010] According to its title, document DE 10 2021 200 339 A1 relates to a sorting system and a method for controlling a sorting system.

[0011] It is an object of the present disclosure to provide an AGV and a method for transporting goods that result in increased throughput (number of transports per unit of time). In particular, the planning and execution of a corresponding transport order should be less complex. Congestion and collisions should be avoided as much as possible.

[0012] This object is achieved by a driverless transport system (FTS) that is configured to carry out grid navigation and that has: a plurality of driverless transport vehicles (FTFs) that are configured for grid navigation, wherein the plurality of FTFs is formed at least by first and second groups of FTFs; a driving surface within which the FTFs move, preferably exclusively, along a, in particular two-dimensional, grid structure that has, preferably regularly arranged, grid points and that is spanned by first and second basis vectors, wherein the FTFs of the first group may only be moved along the first basis vector and wherein the FTFs of the second group may only be moved along the second basis vector; and a controller that is configured to plan or determine a, in particular connected, route along the grid between a predetermined starting point and a predetermined destination point.to generate a route so that selected AGVs transport a cargo item from the starting point to the destination point by transferring it between the selected AGVs. The route corresponds in particular to a transport order that comprises a plurality of AGV-specific travel orders. Each of the AGV-specific travel orders identifies a specific AGV; furthermore, one or more routes assigned to the specific AGV, as well as (optionally) transfer times, transfer speed profiles, stop points, grid intersection points, and the like, can be included in the respective AGV-specific travel order.

[0013] Planning the possible routes of the AGVs is extremely complex in conventional systems because the corresponding transport or travel task is usually only ever carried out by a single AGV, which must move to its destination without collisions, and in particular as quickly as possible and via the shortest route. The corresponding planning requires considering many AGVs simultaneously. By reducing the number of possible directions of travel (for example, forward and backward) and to a corresponding speed vector, the planning can be simplified. However, the route can be determined variably by combining a large number of possible routes accordingly, resulting in several possible solution routes from which to choose. Each of the routes is linked to a different AGV, thus reducing the collision problem in particular.

[0014] The number of possible routes with an identical total length, especially with the same number of handovers along the way, is severely limited. Therefore, an optimization calculation can be performed much faster and requires fewer resources.

[0015] Since the (sub)routes that make up the overall route are preferably linear, with the vehicles being guided mechanically, for example, by rails, the vehicle's path can be anticipated by a person in the immediate vicinity of the vehicle. Collisions can be avoided. Safety requirements can be reduced. People can safely remain in an area where - and while - the vehicles are being operated automatically.

[0016] The crossing or transfer points of the vehicles can also be viewed as sub-destinations, which are reserved or allocated by a route but can be released immediately after a successful passage. This keeps the route binary and highly transparent. Allocation in a driverless transport system refers to a process of allocating and managing transport tasks and resources within the system. This can include decisions about how and when vehicles are deployed to transport goods within a warehouse, a production facility, or another operational area. The allocation process considers various factors such as vehicle availability, the urgency of the transport tasks (prioritization), the most efficient routes, and the minimization of waiting times or empty runs.

[0017] In the overall network, which is superimposed on the transport area, multiple routes can be clearly demarcated from one another and operated by different vehicle groups that do not need to take each other into account. Real-time monitoring, for example, is no longer necessary.

[0018] Reducing the length of the (partial) routes that make up the overall route can also simplify planning. It's easier to coordinate many short routes than a few long ones.

[0019] The use of AGVs eliminates the need for permanently installed conveyors, which also results in a high degree of planning freedom.

[0020] This concept can be used in high-density storage systems as well as in sorting systems (e.g., in a FastBot system). The application possibilities are virtually unlimited, as most systems suffer from performance-reducing traffic problems, especially when large numbers of vehicles are moved simultaneously within a (spatially confined) area.

[0021] Preferably, the starting point and the destination point can only be connected to one another via a combination of the first and second basis vectors, and in particular each correspond to one of the grid points.

[0022] The combination of the base vectors makes it clear that the goods cannot simply be transported along a straight line, but must travel around corners to get from the starting point to the destination. Otherwise, implementing the planned transport route with a single AGV would probably be more sensible.

[0023] The starting point and the destination point each correspond to a different grid point. The routes start and end at the grid points, which in turn simplifies route planning. At the beginning and end, no sections need to be considered that cannot be covered by one of the AGVs. In particular, the grid division, i.e., the relative distances between directly adjacent grid points, can be finely selected to allow for access to every point in space. In this case, every point in space is a possible starting point or destination point.

[0024] Preferably, the route is planned by the controller in such a way that the transported goods are transferred between the selected AGVs of the first and second groups, wherein the selected AGVs meet, in particular synchronized in time, at selected grid points encompassed by the route.

[0025] The planning also takes time into account. The AGVs don't have to wait for each other to hand over or transfer the goods. The travel time from the starting point to the destination is shortened, resulting in higher throughput (for the entire system).

[0026] By having the AGVs meet at the grid points, planning and, in particular, synchronization of the handover process is simplified, since the positions of the grid points or crossing points of the AGVs are known in advance and cannot be varied.

[0027] Preferably, the handover is inertia-based and the controller is further configured to schedule the inertia-based handover.

[0028] If the transfer is inertia-based, active drives are no longer required. AGVs require fewer components and less energy.

[0029] Preferably, each of the AGVs has a load handling device, LAM, with an actively driven conveyor, wherein the transfer of the transported goods is carried out in a particularly actively driven manner.

[0030] An actively driven conveyor simplifies planning compared to inertia-based transfer because corresponding speed adjustments to induce inertial forces are not required. Active transfer is more process-safe and reliable.

[0031] Preferably, the grid structure is formed by columns and rows of paths between, in particular directly adjacent, grid points, wherein the FTFs of the first group are assigned to the rows and the FTFs of the second group are assigned to the columns.

[0032] The groups are therefore clearly assigned different directions of movement. Vehicles in the same group cannot collide with each other, especially if each row and column is occupied by only one of the vehicles.

[0033] This preferably means that each of the rows and each of the columns is provided with a single one of the FTFs.

[0034] Preferably, the travel surface is formed from two movement planes, wherein one of the movement planes is spanned by the first and second base vectors and the other movement plane is spanned by a third base vector and one of the two other base vectors; wherein the plurality of AGVs comprises a third group of AGVs, wherein the AGVs of the third group may only be moved along the third base vector; and wherein the base vectors are preferably oriented perpendicular to one another.

[0035] Because the vehicles can be deployed on two planes of movement, any point in space can be reached, particularly via the vertical direction. In other words, this concept can be implemented not only in a two-dimensional plane, but also in three-dimensional space. One of the groups is active on both planes to transfer the transported goods between the different planes of movement.

[0036] The object is further achieved by a method for transporting a cargo item on a route in an AGV that is configured to carry out grid navigation and that has a plurality of AGVs and a driving surface, wherein the plurality of AGVs is formed by at least first and second groups of AGVs, wherein each of the AGVs is configured for grid navigation and is movable within and along a grid structure corresponding to grid navigation, which defines the driving surface and has the grid points, wherein the driving surface is spanned by first and second basis vectors; wherein the method comprises the steps of: determining the route along the grid between a predetermined starting point and a predetermined destination point; and selecting AGVs (from the first and second groups) such that the selected ones of the AGVs transport a cargo item from the starting point to the destination point by transferring it between the selected AGVs;wherein the AGVs of the first group may only be moved along the first basis vector and wherein the AGVs of the second group may only be moved along the second basis vector.;

[0037] The process can achieve the same advantages as the system.

[0038] Preferably, the method further comprises: transporting the transport goods along the route, wherein the transport goods are transferred at corresponding grid points between the selected AGVs.

[0039] Preferably, the starting point and the destination point can only be used with each other via a combination of the basis vectors, and in particular they correspond to one of the grid points.

[0040] Preferably, the grid structure is formed by columns and rows of paths between adjacent grid points, wherein the FTFs of the first group are assigned to the rows and the FTFs of the second group are assigned to the columns, wherein in particular each of the rows and each of the columns is provided with a single one of the FTFs.

[0041] Preferably, the travel surface is formed from two movement planes, wherein one of the movement planes is spanned by the first and second base vectors and the other movement plane is spanned by a third base vector and one of the other base vectors; wherein the plurality of AGVs comprises a third group of AGVs, wherein the AGVs of the third group may only be moved along the third base vector; and wherein the base vectors are preferably oriented perpendicular to one another.

[0042] Preferably, the route is determined by the controller in such a way that the transported goods are transferred between the selected AGVs of the groups, wherein the selected AGVs meet, in particular synchronized in time, at selected grid points included in the route.

[0043] It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified but also in other combinations or on their own, without departing from the scope of the present concept.

[0044] Examples of the concept are shown in the drawings and explained in more detail in the following description. They show: Fig. 1 a block diagram of an automated guided vehicle; Fig. 2 an illustration of a grid navigation; Fig. 3 a schematic representation of a two-dimensional driving surface in which a possible route between a possible starting point and a possible destination point is drawn; Fig. 4 different vehicle types for use in a driverless transport system, especially in different directions of movement; Fig. 5 an extended driving surface so that AGVs can be used in two movement planes to reach any point in space; Fig. 6 is a flowchart of a method for generating or planning a route; and Fig. 7 a block diagram of a driverless transport system.

[0045] This concept is particularly used in intralogistics. The term "intralogistics" refers to the organization, control, implementation, and optimization of all internal material flow and storage processes. This discipline encompasses the management of goods movements within a company, including warehousing, transportation, and distribution. Intralogistics plays a crucial role in the efficiency and productivity of production and warehouse operations by integrating modern technologies and systems such as automated conveyor systems, robots, warehouse management software, and advanced information technologies. The main objectives of intralogistics include optimizing goods flows within a company to shorten delivery times, reduce costs, improve space utilization, and / or increase productivity.By using intralogistics systems, the company can not only make its internal processes more efficient, but also create a basis for seamless integration with global supply chains.

[0046] The term "material flow" refers to the movement of goods (e.g., raw materials, components, intermediate products, and finished products, as well as warehouse and transport goods) within, through, or from a production and / or warehouse area. It encompasses all processes related to the physical movement of goods, including transportation, storage, picking, and delivery.

[0047] Material flow is a core component of both intralogistics and logistics in general. It aims to optimize efficiency in the production and distribution of goods and to make them available at the right time and place. Effective material flow management minimizes downtime, reduces inventory levels, and accelerates the entire supply chain. Optimizations in material flow can be achieved through automation, improved facility layouts, and the use of advanced planning and control systems.

[0048] Therefore, AGVs 10 are used here, which are moved and navigated along a (virtual or real) grid structure 24, which is also referred to as grid navigation and enables a high degree of flexibility in dynamic environments.

[0049] Fig. 1 shows a block diagram of an AGV 10. The AGV 10 may have several components that enable it to operate autonomously in an environment, such as a driving surface 25 (cf. Fig. 2) to navigate and perform (transport) tasks. The components may include: a drive system 12; a power supply 14; a navigation system 16; a control and communication unit 18; a load handling device (LAM) 20, such as; and / or a safety system 22.

[0050] The drive system 12 may include one or more motors and associated control technology that provide mobility to the AGV 10. Mobility can be achieved through various types of drives, such as wheels or tracks. The power supply 14 is often provided by batteries or fuel cells to power the drive and other functions of the AGV 10. The navigation system 16 may include sensors such as LIDAR, cameras, or ultrasonic sensors, as well as GPS. The control and communication unit 18 may include one or more computers or processors that receive and interpret data from the sensors, control the vehicle's movements, and communicate with other systems or a central controller (AGV fleet manager, warehouse management computer, material flow computer, etc.).This unit 18 is the "brain" of the AGV 10 and can also include corresponding (data) interfaces for sending and receiving corresponding data. The LAM 20 can be a platform sitting on top of a chassis, as described, for example, in DE 10 2019 122 052 B4, to which reference is made here with regard to the platform and chassis, as well as their structure and functionality. The safety system 22 can include emergency stop switches, bumpers, safety light barriers, and / or other devices that ensure that the AGV 10 can operate safely near people and other objects.

[0051] The AGVs 10 of the present concept are capable of various navigation methods to find their way around their environment and reach their destinations. The choice of navigation method often depends on the specific application and environmental conditions. Some of the most common navigation methods for the AGVs 10 are listed below: i.) Inductive navigation, where the AGVs 10 follow a wire embedded in the ground that generates an electromagnetic field and are equipped with sensors that detect this field and follow the path of the wire; ii.) Optical navigation, where markers or tapes attached to the ground are used, which are optically detected by the AGVs 10, and where the vehicles use cameras or other optical sensors to detect these markers and follow a predetermined route; iii.) Laser navigation, where the AGVs 10 use laser distance meters (e.g., LIDAR) to determine their position relative to fixed reference points (e.g.,shelves, walls, workstations, etc.) in their surroundings, which can be done, for example, by scanning reflectors or other prominent features in the environment; iv.) SLAM (Simultaneous Localization and Mapping), which enables the AGVs 10 to map their surroundings and simultaneously determine their position within this map, and where SLAM uses a combination of sensors and complex algorithms to create a dynamic map of the environment and navigate the vehicle accordingly; v.) and / or GPS navigation.

[0052] As in Fig. 2, in general, in grid navigation used in the present concept, a virtual map or grid structure (hereinafter also referred to as "grid") 24 is overlaid over a driving surface 25 (e.g., an open space in a warehouse), wherein each point 26 in the grid 24 can serve as a potential waypoint 27 for the vehicle 10 (not shown). The waypoint 27 can be a starting point 30, a destination point 32, and / or an intersection or transfer point. The AGVs 10 navigate along and through this grid 24 using algorithms that determine a preferably shortest or most efficient overall path or route 28 to a destination point 32, in particular based on real-time data about the environment and possible obstacles. Advantages of grid navigation are flexibility, scalability, and collision avoidance.Since no physical guidelines such as wires or tapes are required, the route 28 can be easily modified and adapted to new layouts of the driving area 25 or tasks. The driving area 25 can be easily expanded by incorporating additional areas into the existing grid 24 without extensive physical changes being required. Modern algorithms enable the AGVs 10 to dynamically adjust their paths 28, for example, to avoid collisions with other AGVs 10 or obstacles. The technology behind grid navigation typically includes advanced sensors and software that continuously collect and process data about the environment. Data collection may include LIDAR, cameras, or other forms of sensing that work together to ensure accurate position and motion detection.

[0053] To avoid collisions between the AGVs 10 during grid navigation, several strategies and technologies are conventionally used. These measures are designed to ensure safe, efficient, and collision-free movement of the AGVs 10 within the grid 24. These strategies and technologies can include: a) collision avoidance algorithms; b) real-time communication and coordination; c) sensors for obstacle detection; d) zone management for traffic control; and / or e) prioritization rules. Collision avoidance algorithms are sophisticated collision avoidance algorithms that dynamically plan and control the movements of the AGVs 10. These algorithms can, for example, use a Dijkstra algorithm or other route finding methods to calculate safe paths 28 through the grid 24 that avoid collisions.Furthermore, the AGVs 10 can be equipped with communication systems configured to share their positions and planned routes 26 in real time with other AGVs 10 and / or a central controller (AGV fleet manager). Through this networking, the AGVs 10 can adapt their routes 28 to the movements of other AGVs 10. In more complex systems, the movement of the AGVs 10 can also be controlled by zone management, in which certain areas of the grid 24 are temporarily blocked and / or reserved for other AGVs 10 to avoid congestion or collisions. This type of traffic control can be managed by the central control software (AGV fleet manager). Prioritization rules are also often defined to determine which of the AGVs 10 has priority if, for example, two or more AGVs 10 meet in the grid 24.Such rules may be based on various factors, such as the urgency of a task, the length of the traveled or remaining distance, or specific traffic rules within the driving area 25. By combining these techniques, the AGVs 10 can navigate efficiently and safely within the grid 24, optimizing the material flow.

[0054] Fig. Figure 2 schematically illustrates grid navigation. This illustration shows, by way of example, a regular grid 24 in which each grid point 26 represents a possible starting point 30, a possible destination point 32 and / or a possible intersection point where a transported goods transfer can take place within a travel area 25. The solid line shows one of many possible routes 28 of an AGV 10 (not shown) through the grid 24. The left point 26-1 in Fig. 2 marks the starting point 30 and the right point 26-2 the destination point 32. Route 28 of the Fig. 2 is composed of ten paths 34. The paths 34 connect directly adjacent grid points 26. In the Fig. 2 shows exemplary horizontal, vertical, and diagonal paths 34. However, it is also possible to consider only horizontal and vertical paths 34, as will be done below.

[0055] The lattice structure 24 of the Fig. 2 is spanned, for example, by two basis vectors V1 and V2, which are preferably oriented perpendicular to each other. The basis vectors V1 and V2 shown here represent mathematical unit vectors that span the driving surface 25. The basis vectors V1 and V2 are in Fig. 2 are the same length, but could also be different lengths. The basis vector V1 extends in the example of Fig. 2 parallel to the (longitudinal) direction Z of a (not shown) storage and order picking system, while the base vector V2 extends parallel to the (transverse) direction X. The vectors V1 and V2 are preferably of equal length. It goes without saying that the driving surface 25 could also be spanned by more than two base vectors Vi. It is also possible that individual ones of the (actually present) grid points 27 are omitted, e.g. because there is an obstacle at a corresponding location in reality or because a prohibited zone (e.g. a work area for people) is defined there, into which the vehicles are not allowed to enter, e.g. for safety reasons. "Directly" adjacent grid points 27 can therefore also be separated from each other by a length that is a multiple of one of the base vectors.

[0056] Furthermore, it is also understood that the grid points 26 of the grid 24 do not necessarily have to be intersection points. The grid points 26 can also form the respective end of a "dead end", as described below in Fig. 3 for the start and destination points 30 and 32. However, the start and destination points 30 and 32 can also be intersection points of the grid 24.

[0057] Fig. Figure 3 illustrates another (two-dimensional) driving surface 25, which is defined by a (two-dimensional) grid structure 24. The (regular) grid structure 24 is also formed by grid points 26. The grid structure 24 of the Fig. 3 essentially corresponds to the lattice structure 24 of the Fig. 2. The 34 routes that are in the Fig. 3 are vertically oriented (longitudinal direction X) and connected to each other, define columns 36 of the grid 24, represented by dashed lines. The paths 34, which are in the Fig. 3 horizontally oriented (transverse direction Z) and connected to each other, define rows 38 of the grid 24, shown by solid lines. Five columns 36-1 to 36-5 and five rows 38-1 to 38-5 are exemplary in Fig. 3. It is understood that generally at least one column 36 and several rows 38 or alternatively several columns 26 and at least one row 38 are provided. Furthermore, five starting points 30-1 to 30-5 and five destination points 32-1 to 32-5 are shown as examples, which do not have to be intersection points and can, for example, be located at the end of a dead end. Points 30 and 32 can also be in the middle of the driving surface 25 of the Fig. 3 or on the left and right side edges. It is understood that the grid 24 of the Fig. 3 could have more or fewer columns 36 and more or fewer rows 38.

[0058] The grid 24 of the Fig. 3 is preferably characterized in that an AGV 10 is provided for each of the columns 36 and for each of the rows 38. In other words, this means that an AGV 10 is provided in each of the columns 36 and in each of the rows 38. It is understood that more than one AGV 10 can be provided per column 36 and per row 38. However, it is assumed that the AGVs 10 can only move along the direction assigned to them (X or Z). In other words, this means that the AGVs 10 preferably only move or are allowed to move in the X direction or in the Z direction, so that in this case the AGVs 10 should only travel straight ahead (back and forth) but should not turn. Fig. 3, the AGVs 10-1 to 10-5 therefore only move horizontally or transversely in the direction Z along the rows 38 assigned to them, whereas the AGVs 10-6 to 10-10 only move vertically or longitudinally in the direction X along the columns 36 assigned to them.

[0059] Furthermore, the Fig. 3 an exemplary route 28 is illustrated by a dotted line extending from the starting point 30-2 to the destination point 32-4. The route 28 of the Fig. 3 is such that the vehicles 10-7, 10-2, 10-8, 10-4, and 10-9 are used for its implementation, particularly in the order indicated. The vehicle 10-7 picks up a transport item 40 (not shown) from the starting point 30-2 and then transfers the transport item 40 to the vehicle 10-2, as shown in Fig. 3, where the vehicles 10-7 and 10-2 are positioned directly opposite each other. The movements of the vehicles 10-7 and 10-2 are coordinated (synchronized) such that the vehicles 10-7 and 10-2 meet at a predetermined location (intersection point) at a predetermined time with predetermined speeds. In the example of Fig. 3, vehicle 10-2 is already waiting at the corresponding grid point for vehicle 10-7, which in turn approaches vehicle 10-2 with a predetermined movement sequence and comes to a stop there. Vehicle 10-2 thus transfers the transported item 40 to vehicle 10-8, which then transfers the transported item 40 to vehicle 10-4, which then finally transfers the transported item 40 to vehicle 10-9, which in turn delivers the transported item 40 to the destination point 32-4.

[0060] In the Fig. 3, it has been tacitly assumed that the vehicles 10 can move bidirectionally, i.e., forward and backward. However, it is also possible for the vehicles 10 to move in only one direction. The columns 26 and the rows 38 could be implemented as self-contained loops along which the vehicles 10 circulate endlessly. In general, each - or several - of the paths 34 could be implemented as a respective loop.

[0061] The transfer can be active or passive. In the case of an active transfer, the LAMs 20 of the cooperating vehicles 10 are equipped with drives to actively move the transported goods 40 during the transfer. The LAM 20 can be implemented, for example, by a roller conveyor or belt conveyor, on the top of which the transported goods are placed and can preferably be moved linearly. Alternatively, a so-called matrix conveyor can be used, which can move the transported goods placed on it in different directions - and thus deliver them. Such a matrix conveyor is described, for example, in the document DE 10 2010 015 584 A1. In the case of a passive transfer, it is not mandatory for the LAMs 20 of the cooperating vehicles 10 to be (each) equipped with a (separate) drive to move the transported goods 40 during the transfer. In this case, the LAM 20 can simply be a platform on which the transported goods are placed.A surface of the platform may have a suitable coefficient of friction to support inertial-based handover.

[0062] The following describes a passive, inertia-based transfer of a transport item 40 from a first AGV 10 to a second AGV 10. In this example, the inertia-based transfer refers to a method in which the physical inertia of the transport item 40 is used to transfer it from the first AGV 10 to the LAM 20 of the second AGV 10 or to another area (e.g., to a stationary transfer station), in particular without using mechanical aids such as conveyor belts or robot arms.

[0063] The transfer could, for example, look like this: The first AGV 10 accelerates or decelerates so that the transport item 40 located thereon is brought into a specific position on the LAM 20 by the inertial force caused by the speed adjustment. The transport platform of the LAM 20 can, for example, be provided at least partially in its circumferential direction with a fence-like holder that protrudes vertically from the transport platform in order to be able to hold the transport item 40 on the platform during a journey of the AGV 10 or to release it, as described, for example, in the document DE 10 2019 122 052 B4. The AGV 10 can be configured to be stopped abruptly at a specific (grid) point, whereby the transport item 40 continues to move in the original direction of movement due to its inertia and is thus transported to another platform or into another area, i.e. using gravity and / or movement.

[0064] Upon reaching its destination, i.e., the transfer location, the first AGV 10 could be braked so gently that the transported goods 28, due to inertia, slide or slide from the platform of the LAM 20 of the first AGV 10 onto the platform of the LAM 20 of the second AGV 10 or slide or slide onto the platform of a receiving station (not shown). This method minimizes mechanical wear because the first and second AGVs 10 and 10 do not mechanically collide with each other, and it makes the transfer process more efficient and faster.

[0065] The way in which the transfer takes place depends on the type of vehicle chosen. Fig. 4 shows several different vehicle types for the FTF 10 as examples. Fig. 4A shows an AGV type 10A, in which the AGV 10 (here in the longitudinal direction X) is moved in a forced manner, whereby the forced guidance can be virtual (for example optical or inductive) or mechanical (for example by means of rails, which are not shown). Fig. 4B shows an AGV type 10B, in which the AGV 10 (here in the transverse direction Z) is mechanically guided by means of a rail. Fig. 4C shows an AGV type 10C, in which the AGV 10 is designed like a portal in order to drive over the AGV type 10A during an exchange of a transport item, for example, so that the transport item 40 can be lifted or lowered. Fig. 4D shows an AGV type 10D with a cantilever arm that projects laterally over the corresponding vehicle in order to exchange the transported goods 40 vertically in the height direction Y. The Fig. 4B to 4D have in common that the exchange of the transported goods 40 is carried out using the AGV type 10A, whose vehicle preferably enters the vehicles of types 10B to 10D (in the longitudinal direction X) after these vehicles have been appropriately positioned in advance. Fig. 4, the transported item 40 is illustrated as an example of a transport container. It is understood that the transported item 40 can generally also be implemented as packages, bags, or other similar load carriers (with or without cargo).

[0066] In particular, the AGV types 10C and 10D illustrate the possibility of using the concept presented here in the field of so-called "High-Density Storage" (HDS) systems, which are commercially available, for example, under the (registered) trademark "AutoSore"™. In this case, the vehicles can be positioned on top of the "roof" of a shelf-like container storage cube and moved to move containers stacked on top of each other (vertically and horizontally). On the roof of the corresponding cube, grid-like guide rails can be provided for the forced guidance of the vehicles, which in Fig. 4 but are not shown.

[0067] Fig. Figure 5 visualizes a combination of the previously described two-dimensional concept to also cover the third dimension (height direction Y) with regard to material flow. The travel surface 25 of the previously described concept extends exclusively in the XZ plane, which can be rotated 90° around the X-axis or Z-axis to subsequently lie in the XY plane or YZ plane, respectively. Fig. 5 illustrates, in addition to the previously described travel surface 25, which represents a horizontally oriented movement plane, an additional travel surface located in the XY plane and representing a vertically oriented movement plane for the vehicles. To implement the vehicle movements along the height direction Y, another AGV type 10E can be used, which, for example, is designed like a lifter, moves (exclusively) in the height direction Y, and is configured to exchange the transported goods 40 with the AGV 10, for example, according to type 10A, which in turn moves (exclusively) in the longitudinal direction X. In other words, this means that, in order to cover all three spatial directions X, Y, and Z with regard to a material flow, two two-dimensional systems can be merged with one another according to the present concept. The merged system is designed like a tensor and represents a three-dimensional arrangement or 3D matrix of grid points 26.The lift-type vehicles 10E define a third group 54 of AGVs 10, which may only be moved along a third base vector V3 oriented parallel to the vertical direction Y. The second and third base vectors V2 and V3 define the additional travel area corresponding to the XY plane. The base vectors are preferably oriented perpendicular to each other.

[0068] Fig. 6 illustrates a flow chart 100 for planning a route 28, in particular in the two-dimensional driving surface 25 in the XZ plane (cf. Fig. 3 and Fig. 5). When planning route 28, a travel order is generated, which can include several partial travel orders for implementation by a plurality of AGVs 10.

[0069] In a step S102, the route 28 is determined by a controller 52 of a driverless transport system (FTS) 50. The FTF 50 is simultaneously referred to the Fig. 7 will be explained later. The FTS 50 comprises a large number (fleet) of the FTF 10, as exemplified with reference to Fig. 1. The plurality is divided into at least a first group 54-1 and a second group 54-2.

[0070] Thereafter, in a step S104, suitable AGVs 10 are selected from the first and second groups 54-1 and 54-2 of AGVs 10 in order to transport a transport item 40 from its predetermined starting point 32 to its predetermined destination point 32 by transferring the transport item 40 between selected AGVs 10 (cf. Fig. 3). The AGVs 10 of the first group 54-1 may only move along a first base vector V1, whereas the AGVs 10 of the second group 54-2 may only move along a second base vector V2, which differs from the first base vector V1 and which, together with the first base vector V1, defines the (two-dimensional) driving surface 25, as already described above for the Fig. 2 and Fig. 3. The controller 52 thus selects one or more of the AGVs 10 from the first group 54-1, which move, for example, only in the transverse direction Z, and one or more AGVs 10 from the second group 54-2, which move only in the longitudinal direction X, such that the transported goods 40 reach their destination point 32 through a respective transfer between the selected AGVs 10.

[0071] Conventionally, a single conventional vehicle is selected, which is permitted to move in both directions X and Z to travel the entire route 28 (without transferring the transported goods 40). According to the present concept, the entire route 28 is divided into many sub-routes (routes 34) with corresponding partial travel orders, which together result in a contiguous transport route corresponding to the route 28. For dividing the route 28 into sub-routes, there are many different solutions that the controller 52 can weigh against each other, also taking into account (traffic) parameters, in order to achieve an optimal result in terms of throughput (transports / unit of time). These parameters can include: an AGV-specific utilization or availability; a traffic density; a priority of the transported goods 40; and / or the like.

[0072] The points 32 (destination) and 30 (start) can optionally be specified to the controller 52 in one or more steps S106 or S108 by an external entity, such as a material flow computer (not shown), through a corresponding (data) transmission. The specified points 30 and 32 are characterized by the fact that they can only be connected to each other by a combination of the basis vectors V1 and V2. In other words, this means that the points 30 and 32 are not on a "straight line" (cf. row 34 or column 36 in Fig. 3) that could be traveled by a single AGV 10 (of the first group 54-1 or the second group 54-2) alone. In this sense, a change of direction must occur, which is only possible if the transport item 40 is transferred between the AGV 10 of the two groups 54-1 and 54-2, as described above. Route 28 represents a continuous, i.e., uninterrupted, connection between points 30 and 32.

[0073] Step S102 of determining route 28 and step S104 of selecting AGV 10 from the two groups 54-1 and 54-2 may coincide, i.e., be identical. By selecting AGV 10, route 28, of which initially only the starting and destination points 30 and 32 are known, is determined as a whole.

[0074] However, step S104 of selecting the AGVs 10 can not only determine which of the AGVs 10 are involved in completing the corresponding transport order. In step S104, times can also be specified at which the selected AGVs 10 (should) meet at the corresponding intersection points, i.e., grid points 26, for transferring the transported goods 40, which is particularly important in the case of an inertia-based transfer. Without an inertia-based transfer, however, it is also possible for one of the AGVs 10 to wait for the other of the AGVs 10, depending on which of the AGVs 10 that are to exchange the transported goods arrives at the selected intersection point first.

[0075] The controller 52 can have the functionality of a conventional control system (fleet manager). Control systems in conventional AGVs ensure that each vehicle is assigned a driving order centrally and automatically. A driving order is defined by at least one of the destination points 32 within the driving area 25, where the goods to be transported are to be delivered. A destination is usually assigned by a driving order processing system (disposition of driving orders), which is integrated into the control system or can be implemented independently. The driving order also includes an assigned starting point 30. A driving order can further include all intersection points essential for navigation, i.e. grid points 26, between the start and destination points 30 and 32, wherein a map of the driving area 25, i.e. the arrangement of the grid points 26 including their positions and distances, is stored in the control system and wherein the navigation orPathfinding is performed centrally by the control system. In this case, the control system determines (in advance and / or dynamically in real time) the path or route 28 through the driving surface 25, from the start to the destination. Navigation or pathfinding is performed centrally in this case.

[0076] Optionally, the map can (also) be stored in each of the AGVs 10. The entire travel order, which corresponds to route 28 from starting point 30 to destination 32, can in this case be composed of a corresponding number of AGV-specific travel sub-orders. Each AGV-specific travel order essentially includes at least the final destination 32. Furthermore, the AGV 10 can specify an intersection point (grid point 26) of route 28 that can be reached by the corresponding AGV 10. The AGV 10 can freely determine the intersection point and its movement up to this intersection point. The selection of the intersection point determines which AGV 10 of the other group must pick up and collect the associated transport item 40. The AGVs 10 communicate all relevant information with each other. In this case, the vehicles have their own corresponding "intelligence", i.e.Each of the vehicles is equipped with a corresponding data processing and communication device (microcontroller, computer, etc.), see . Fig. 1. In this case, navigation or pathfinding is carried out decentrally and, in particular, dynamically. The participating AGVs 10 coordinate with each other, for example, by the AGV 10 currently carrying the transported goods 40 transmitting the final destination 32 to all other, or at least to the locally neighboring, AGVs 10. These AGVs 10 can then decide for themselves whether they are free (i.e., unloaded) and whether their route brings the transported goods closer to their destination 32. Pathfinding is therefore carried out dynamically, i.e., in real time and randomly, whereby optimizations (e.g., shortest route, shortest transport time, etc.) can be taken into account.

[0077] Regardless of whether navigation is centralized or decentralized, each vehicle can be in almost continuous (data-related) contact with the control system and / or the other vehicles via a communication channel in order to at least exchange the destination and instructions for regulating the traffic between the vehicles (traffic regulation or control). For traffic regulation, the control system can prioritize specific driving orders that are assigned to specific vehicles. This means, for example, that a specific vehicle can always have right of way over all other vehicles. If the control system detects from the current (vehicle) data (position, order, speed, etc.) that a collision, jam, or traffic jam is imminent, the control system can regulate traffic, taking any prioritizations into account, in such a way that no collision, jam, or traffic jam occurs. For this purpose, the control system can, for example,B. communicate with all FTF 10s in the fleet via a (computer) network, e.g. WLAN.

[0078] The term "fleet" therefore generally refers to the multitude of AGVs 10. A single AGV 10 cannot form a fleet. The AGVs 10 are configured in advance for this purpose, i.e. each AGV 10 has an individual identifier. The master control system can then specifically address and track each AGV. Tracking affects both the driving order and the (current) position of the vehicle in the driving area 25. Traffic control can be implemented via the position reported back to the master control system by the respective AGV 10. If two of the AGVs 10 are on a collision course, for example, the master control system intervenes by decelerating or stopping one of the AGVs 10 in order to prevent the impending collision. This requires position transmission for the AGVs 10 in near real time. Conventional position determination can in turn be carried out (centrally) in the master control system and / or (decentrally) in the AGVs 10 themselves. List of reference symbols 10 Automated Guided Vehicles (AGVs) 12 Drive system of the AGV 14 Power supply of the AGV 16 FTF navigation system 18 Control and communication unit of the AGV 20 load handling equipment (LAM) from the AGV 22 AGV safety system 24 lattice structure 25 Driving surface 26 grid points 27 Waypoint 28 Route, path or navigation path 30 Starting point 32 Destination point 34 route 36 columns 38 row 40 transport goods 50 FTS 52 Control 54 groups of FTF 10-1 first AGV in a handover process 10-2 second AGV in a handover process

Claims

[1] Automated guided vehicle system (AGV) (50) which is designed to perform grid navigation and which comprises: a plurality of driverless transport vehicles, FTF, (10) configured for grid navigation, wherein the plurality of FTF (10) is formed by at least first and second groups of FTF (10); a travel surface (25) within which the AGVs (10) move along a grid structure (24) having grid points (26) and spanned by first and second basis vectors (V1, V2), and wherein the AGVs (10) of the first group (54-1) may only be moved along the first basis vector (V1) and wherein the AGVs (10) of the second group (54-2) may only be moved along the second basis vector (V2); and a controller (18; 52) which is configured to plan a route (28) along the grid (24) between a predetermined starting point (30) and a predetermined destination point (32), so that selected ones of the AGVs (10) transport a transport item (40) from the starting point (30) to the destination point (32) by transferring it between the selected AGVs (10). [2] FTS (50) according to claim 1, wherein the starting point (30) and the destination point (32) can only be connected to one another via a combination of the first and second basis vectors (V1, V2), and in particular each correspond to one of the grid points (24). [3] AGV (50) according to claim 1 or 2, wherein the route (28) is planned by the controller (18; 52) such that the transported goods (40) are transferred between the selected AGVs (10) of the first and second groups (54-1, 54-2), wherein the selected AGVs (10) meet at selected ones of the grid points (26) encompassed by the route (28). [4] AGV (50) according to one of claims 1 to 3, wherein the handover is inertia-based and the controller (18; 52) is further configured to schedule the inertia-based handover. [5] AGV (50) according to one of claims 1 to 4, wherein each of the AGVs (10) has a load-handling device, LAM, (20) with an actively driven conveyor, wherein the transfer of the transported goods (40) is carried out in particular in an actively driven manner. [6] AGVs (50) according to one of claims 1 to 5, wherein the grid structure (24) is formed by columns (36) and rows (38) of paths (34) between adjacent ones of the grid points (26), wherein the AGVs (10) of the first group (54-1) are assigned to the rows (38) and the AGVs (10) of the second group (54-2) are assigned to the columns (36). [7] AGV (50) according to claim 6, wherein each of the rows (38) and each of the columns (36) is provided with a single one of the AGVs (10). [8] FTS (50) according to one of claims 1 to 7, wherein: the driving surface (25) is formed from two planes of movement, one of the planes of movement being spanned by the first and second base vectors (V1, V2) and the other plane of movement being spanned by a third base vector (V3) and one of the first and second base vectors (V1, V2); the plurality of AGVs (10) comprises a third group (54-3) of AGVs (10), wherein the AGVs (10) of the third group (54-3) may only be moved along the third base vector (V3); and the basis vectors (V1, V2, V3) are preferably oriented perpendicular to each other. [9] Method (100) for transporting a transport item (40) on a route (28) in an AGV (50) which is configured to carry out grid navigation and which has a plurality of AGVs (10) and a driving surface (25), wherein the plurality of AGVs (10) is formed by at least first and second groups (54-1, 54-2) of AGVs (10), wherein each of the AGVs (10) is configured for grid navigation and is movable within and along a grid structure (24) corresponding to the grid navigation, which defines the driving surface (25) and has the grid points (26), wherein the driving surface (25) is spanned by first and second basis vectors (V1, V2); wherein the method comprises the steps: Determining (S102) the route (28) along the grid (24) between a predetermined starting point (32) and a predetermined destination point (30); and Selecting (S104) AGVs (10) from the first and second groups (54-1, 54-2) such that the selected AGVs (10) transport a transport item (40) from the starting point (32) to the destination point (20) by transferring it between the selected AGVs (10); wherein the FTF (10) of the first group (54-1) may only be moved along the first base vector (V1) and wherein the FTF (10) of the second group (54-2) may only be moved along the second base vector. [10] The method of claim 9, further comprising: Transporting the transport goods (40) along the route (28), wherein the transport goods (40) are transferred at corresponding grid points (26) between the selected AGVs (10). [11] Method according to claim 9 or 10, wherein the starting point (30) and the target point (32) can only be connected to one another via a combination of the first and second basis vectors (V1, V2), and in particular each correspond to one of the grid points (26). [12] Method according to one of claims 9 to 11, wherein the grid structure (24) is formed by columns (36) and rows (38) of paths (34) between adjacent ones of the grid points (26), wherein the FTFs (10) of the first group (54-1) are assigned to the rows (38) and the FTFs (10) of the second group (54-2) are assigned to the columns (36). [13] The method (100) of claim 12, wherein each of the rows (38) and each of the columns (36) is provided with a single one of the FTFs (10). [14] A method according to any one of claims 9 to 13, wherein: the driving surface (25) is formed from two planes of movement, one of the planes of movement being spanned by the first and second base vectors (V1, V2) and the other plane of movement being spanned by a third base vector (V3) and one of the first and second base vectors (V1, V2); the plurality of AGVs (10) comprises a third group (54-3) of AGVs (10), wherein the AGVs (10) of the third group (54-3) may only be moved along the third base vector (V3); and the basis vectors (V1, V2, V3) are preferably oriented perpendicular to each other. [15] Method according to one of claims 9 to 14, wherein the route (28) is determined by the controller (52) such that the transported goods (28) are transferred between the selected AGVs (10) of the groups (54-1, 54-2, 54-3), wherein the selected AGVs (10) meet at selected ones of the grid points (26) encompassed by the route (28).

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