Method, system and computer program product for controlling movement of a plurality of container handling vehicles

Abstract

The present invention relates to a system and method for controlling the movement of a plurality of container transport vehicles on a track system arranged at least partially across the top of a frame structure of an automated storage and retrieval system, the plurality of container transport vehicles being operable on the track system to transport storage containers, wherein a control system in communication with a local controller in each container transport vehicle performs the following steps: - instructing a first container transport vehicle to move in a first direction toward a grid cell designated as a first target location on the track system; and - instructing a second container transport vehicle to move in the first direction toward the first target location such that the second container transport vehicle physically contacts the first container transport vehicle, and the second container transport vehicle applies a thrust to the first container transport vehicle after contacting the first container transport vehicle to maintain physical contact.

Description

Technical Field

[0001] The present invention relates to an automated storage and retrieval system for storing and retrieving storage containers transported by container transport vehicles, and more particularly to a method, system and computer program for controlling the movement of a plurality of physically connected container transport vehicles. Background Technology

[0002] Figure 1 discloses a typical prior art automated storage and retrieval system 1 with a frame structure 100, and Figures 2 and 3 disclose two different prior art container handling vehicles 201 and 301 suitable for operation on such system 1.

[0003] The frame structure 100 includes upright members 102, horizontal members 103, and storage volumes comprising storage rows 105 arranged between the upright members 102 and the horizontal members 103. In these storage rows 105, storage containers 106 (also referred to as boxes) are stacked one on top of another to form a stack 107. Members 102 and 103 can typically be made of metal, such as extruded aluminum profiles.

[0004] The frame structure 100 of the automated storage and retrieval system 1 includes a track system 108 arranged across the top of the frame structure 100. Multiple container handling vehicles 201, 301 operate on the track system 108 to raise and lower storage containers 106 from and into storage columns 105, and also to transport storage containers 106 above the storage columns 105. The track system 108 includes: a first set of parallel tracks 110 arranged to guide the container handling vehicles 201, 301 to move across the top of the frame structure 100 in a first direction X; and a second set of parallel tracks 111 arranged perpendicular to the first set of tracks 110 to guide the container handling vehicles 201, 301 to move in a second direction Y perpendicular to the first direction X. Containers 106 stored in the columns 105 are accessed by the container handling vehicles through access openings 112 in the track system 108. The container handling vehicles 201, 301 can move laterally above the storage columns 105, i.e., in a plane parallel to the horizontal XY plane.

[0005] The upright members 102 of the frame structure 100 can be used to guide the storage containers during the process of raising and lowering the containers into the column 105. The stack 107 of the containers 106 is typically self-supporting.

[0006] Each prior art container handling vehicle 201, 301 includes a body 201a, 301a, and a first set of wheels and a second set of wheels 201b, 301b, 201c, 301c, which enable the container handling vehicle 201, 301 to move laterally in the X and Y directions, respectively. In Figures 2 and 3, two wheels in each set are fully visible. The first set of wheels 201b, 301b are arranged to engage with two adjacent tracks of a first set of tracks 110, and the second set of wheels 201c, 301c are arranged to engage with two adjacent tracks of a second set of tracks 111. At least one set of wheels 201b, 301b, 201c, 301c can be raised and lowered, such that the first set of wheels 201b, 301b and / or the second set of wheels 201c, 301c can engage with the corresponding set of tracks 110, 111 at any given time.

[0007] Each prior art container handling vehicle 201, 301 also includes a lifting device (not shown) for vertically transporting the storage container 106, such as raising the storage container 106 from and lowering it into the storage row 105. The lifting device includes one or more clamping / engaging devices adapted to engage the storage container 106, and these clamping / engaging devices are lowerable from the vehicle 201, 301 such that their position relative to the vehicle 201, 301 is adjustable in a third direction Z orthogonal to the first direction X and the second direction Y. A portion of the clamping device of the container handling vehicle 301 is indicated by reference numeral 304 in FIG. 3. The clamping device of the container handling device 201 is located within the vehicle body 201a in FIG. 2.

[0008] Typically, and for the purposes of this application, Z=1 represents the uppermost layer of the storage container, i.e., the layer directly below the track system 108; Z=2 represents the second layer below the track system 108; Z=3 represents the third layer, and so on. In the exemplary prior art disclosed in FIG1, Z=8 represents the lowest layer of the storage container. Similarly, X=1…n and Y=…n represent the position of each storage column 105 in the horizontal plane. Thus, as an example, and using the Cartesian coordinate system X, Y, Z indicated in FIG1, the storage container identified as 106' in FIG1 can be said to occupy storage position X=10, Y=2, Z=3. The container transport vehicles 201, 301 can be said to travel in layer Z=0, and each storage column 105 can be identified by its X and Y coordinates.

[0009] The storage volume of the frame structure 100 is typically referred to as grid 104, and the possible storage locations within this grid are referred to as storage cells. Each storage column can be identified by its position in the X and Y directions, while each storage cell can be identified by its container number in the X, Y, and Z directions.

[0010] Each prior art container handling vehicle 201, 301 includes a storage compartment or space for receiving and loading the storage container 106 when transporting it across the track system 108. The storage space may include a cavity centrally located within the vehicle body 201a, as shown in FIG2, and as described, for example, in WO2015 / 193278A1.

[0011] Figure 3 shows an alternative configuration of the container handling vehicle 301 with a cantilever structure. Such a vehicle is described in detail, for example, NO317366.

[0012] Figure 4 illustrates another type of container handling vehicle, which is in the form of a container transport vehicle 401. This container transport vehicle includes a container carrier arranged above the vehicle body 401a to receive storage containers 106. The container transport vehicle 401 includes a drive unit 401b in a first direction X and a drive unit 401c in a second direction Y, similar to the drive units of the other container handling vehicles 201, 301 described above.

[0013] The central cavity container transport vehicle 201 shown in Figure 2 may have an occupying space covering a certain area in the X and Y directions, the size of which is typically equal to the lateral extent of the storage column 105, for example, as described in WO2015 / 193278A1. The term “lateral” as used herein may mean “horizontal”.

[0014] Alternatively, the central cavity container transport vehicle 101 may have an occupation space greater than the lateral area defined by the storage column 105, for example, as disclosed in WO2014 / 090684A1.

[0015] The track system 108 typically includes a track with grooves in which the vehicle's wheels travel. Alternatively, the track may include upwardly projecting elements, where the vehicle's wheels include flanges to prevent derailment. These grooves and upwardly projecting elements are collectively referred to as guide rails. Each track may include one guide rail, or each track may include two parallel guide rails.

[0016] WO2018 / 146304 illustrates a typical construction of a track system 108, which includes tracks and parallel guide rails in the X and Y directions.

[0017] In frame structure 100, most columns 105 are storage columns 105, i.e., columns 105 where storage containers 106 are stored in stacks 107. However, some columns 105 may serve other purposes. In Figure 1, columns 119 and 120 are dedicated columns for unloading and / or picking up storage containers 106 using container handling vehicles 201, 301, so that they can be transported to an access station (not shown) where the storage containers 106 can be accessed from outside frame structure 100, or transferred out of or into frame structure 100. In the art, such a location is commonly referred to as a “port,” and the columns where the ports are located may be referred to as “port columns” 119, 120. Transport to the access station can be in any direction, i.e., horizontal, inclined, and / or vertical. For example, storage container 106 can be placed in a random or dedicated column 105 within the frame structure 100, and then picked up by any container handling vehicle and transported to port columns 119, 120 for further transport to the retrieval station. It should be noted that the term "inclined" means the transport of storage container 106 having a general transport direction between horizontal and vertical.

[0018] In Figure 1, the first port column 119 may be a dedicated unloading port column, where container handling vehicles 201 and 301 can unload the storage container 106 to be transported to the storage station or transfer station, and the second port column 120 may be a dedicated pickup port column, where container handling vehicles 201 and 301 can pick up the storage container 106 that has been transported from the storage station or transfer station.

[0019] The storage and retrieval station can typically be a pick-up station or a storage station, where product items are removed from or located within storage container 106. At the pick-up station or storage station, storage container 106 is not typically removed from the automated storage and retrieval system 1, but is instead returned to the frame structure 100 once retrieved. The port can also be used to transfer storage containers to another storage facility (e.g., to another frame structure or to another automated storage and retrieval system), to a transport vehicle (e.g., a train or truck), or to a production facility.

[0020] Storage containers are typically transported between port columns 119, 120 and the access station using a transmitter system that includes a transmitter.

[0021] If port columns 119, 120 and access stations are located at different heights, the conveyor system may include a lifting device with vertical components for vertically transporting storage container 106 between port columns 119, 120 and access stations.

[0022] The transport system can be arranged to transfer storage container 106 between different frame structures, for example, as described in WO2014 / 075937A1.

[0023] When access is required for a storage container 106 stored in one of the columns 105 shown in Figure 1, one of the container handling vehicles 201, 301 is instructed to remove the target storage container 106 from its position and transport it to the unloading port column 119. This operation includes moving the container handling vehicles 201, 301 to a position above the storage column 105 where the target storage container 106 is located, removing the storage container 106 from the storage column 105 using the lifting device (not shown) of the container handling vehicles 201, 301, and transporting the storage container 106 to the unloading port column 119. If the target storage container 106 is located deep within the stack 107, i.e., one or more other storage containers 106 are located above the target storage container 106, the operation also includes temporarily moving the storage container located above before lifting the target storage container 106 from the storage column 105. This step, sometimes referred to in the art as “digging,” can be performed using the same container handling vehicle subsequently used to transport the target storage container to unloading port column 119, or using one or more other cooperating container handling vehicles. Alternatively or additionally, the automated storage and retrieval system 1 may have container handling vehicles specifically designed for the task of temporarily removing storage containers from storage column 105. Once the target storage container 106 has been removed from storage column 105, the temporarily removed storage container can be repositioned back into the original storage column 105. However, the removed storage container can alternatively be repositioned to another storage column.

[0024] When storage container 106 is to be stored in a column 105, one of the container handling vehicles 201, 301 is instructed to pick up storage container 106 from pick-up port column 120 and transport the storage container to a position above the storage column 105 to which it is to be stored. After any storage container located at or above the target position within the storage column stack 107 has been removed, the container handling vehicle 201, 301 positions storage container 106 in the desired position. The removed storage container can then be lowered back into storage column 105 or repositioned to another storage column.

[0025] In order to monitor and control the automated storage and retrieval system 1, such as monitoring and controlling the position of the respective storage containers 106 within the frame structure 100, the contents of each storage container 106, and the movement of the container transport vehicles 201, 301, so that the desired storage container 106 can be delivered to the desired location at the desired time without the container transport vehicles 201, 301 colliding with each other, the automated storage and retrieval system 1 includes a control system 121, which is typically computerized and typically includes a database for tracking the storage containers 106.

[0026] WO2019 / 086237 describes a storage system comprising multiple vehicles for transporting storage containers. The multiple vehicles include a plurality of trolleys connected to each other, as well as a first drive vehicle and a second drive vehicle.

[0027] CN211033920 describes a material storage system that includes a push-pull assembly for driving a dump truck to move along a circulating conveyor line.

[0028] US2018162639 describes a storage system including a turning device adapted to turn a container from a moving device to a storage location and from a storage location to a moving device.

[0029] WO2017 / 121512 describes a storage system in which container transport vehicles are equipped with sensors that detect the position of the vehicles and proximity sensors that detect the positions of nearby vehicles, and transmit this information to a control system. The control system communicates with multiple container transport vehicles and commands them to form a “queue,” that is, multiple container transport vehicles arranged substantially in series and configured to move in series with each other. The assembly of this queue is accomplished by means of sensors in the container transport vehicles, by the control system’s knowledge of the relative positions of the container transport vehicles, or a combination of both. However, the position of a container transport vehicle on the track system is not definitively known until it has passed a track intersection, after which the position can be transmitted to the control system that processes this information. This results in delays due to commands being forwarded through and processed by the control system, and leads to insufficient positioning information for effective queue driving of the container transport vehicles. Various methods for mitigating this problem are described, such as adding proximity sensors or physical connections, such as latches, magnetic connections, etc., to each container transport vehicle.

[0030] This delay is particularly problematic around ports and similar locations where container handling vehicles tend to queue. This is illustrated with reference to Figures 5a through 5d. Both the first container handling vehicle 501 and the second container handling vehicle 502 have the same grid cells as their final destination location TP1. The grid cells will typically be ports, where the container handling vehicles perform actions such as lifting and lowering storage containers.

[0031] Figure 5a illustrates the first step, in which the first container transport vehicle 501 is instructed to move to the final target location TP1, and the second container transport vehicle 501 is instructed to move to a location (grid cell) next to the final target location TP1.

[0032] Figure 5b illustrates the next step, where the first container transport vehicle 501 has completed its action at the final target location TP1 and begins to move out of TP1. The second container transport vehicle 502 does not move.

[0033] Figure 5c illustrates the next step, where the first container transport vehicle 501 is outside TP1, meaning the first container transport vehicle 501 has passed the guide rail intersection on the track system 108. After the first container transport vehicle 501 has completely left TP1, it sends a confirmation message that it has moved out of TP1 to the control system. The second container transport vehicle 502 does not move.

[0034] Figure 5d shows the next step, in which the second container transport vehicle 502 has been instructed to move to the final target location TP1.

[0035] This invention relates to a solution for queue driving of container handling vehicles to save time around ports, thereby avoiding the need to wait for confirmation messages and movement instructions.

[0036] Therefore, the present invention solves the problem by mechanically queuing the container transport vehicles 501 and 502. The container transport vehicles 501 and 502 travel one after another without being held together by anything in fact. The container transport vehicles are kept in sequence by making the last container transport vehicle travel slightly faster than the preceding container transport vehicle, and by making the preceding container transport vehicle brake slightly more than the last container transport vehicle.

[0037] This solution can also be used for longer queues, in which case the third container transport vehicle moves faster than the second container transport vehicle, the fourth container transport vehicle moves faster than the third container transport vehicle, and so on. Summary of the Invention

[0038] The invention is set forth and characterized in the independent claims, while the dependent claims describe other features of the invention.

[0039] In one aspect, the invention relates to a method for controlling the movement of a plurality of container transport vehicles on a track system arranged at least partially across the top of a frame structure of an automated storage and retrieval system, the plurality of container transport vehicles being operable on the track system to transport storage containers, wherein the following steps are performed by a control system in communication with a local controller in each container transport vehicle.

[0040] Instruct the first container transport vehicle to move in a first direction toward a grid cell designated as a first target location on the track system, and

[0041] The second container transport vehicle is instructed to move toward the first target location in a first direction, such that the second container transport vehicle physically contacts the first container transport vehicle, and after contacting the first container transport vehicle, the second container transport vehicle applies a thrust to the first container transport vehicle to maintain physical contact.

[0042] The advantage of this invention is that it allows multiple container handling vehicles to mechanically queue, saving time around the port and thus avoiding the need to wait for confirmation messages and instructions to move.

[0043] The target position can be any position on the track system. It can be the final position on the track system, such as a port position, or it can be any intermediate position along the way to the final position. For example, a vehicle can be instructed step-by-step to move to a first position on the track system, where it waits for another vehicle to pass, and then receives instructions to move to a second position.

[0044] Instructing the application of thrust may include instructing the second container handling vehicle to apply a non-thrust force exceeding the amount required for the movement of the second container handling vehicle. The non-thrust force may exceed 2-25%, preferably 2-10%, or most preferably 3-8%.

[0045] Thrust and non-thrust can be determined by measuring the power usage of the second container handling vehicle.

[0046] Instructing the application of thrust may include instructing the second container vehicle to move according to a motion vector exceeding that of the first container handling vehicle in the first direction. The corresponding motion vector of the first container handling vehicle in the first direction may exceed this vector by 2-25%, preferably 2-10%, or most preferably 3-8%.

[0047] In one embodiment, the method may further include stopping the application of thrust to the first container transport vehicle after determining that the first container transport vehicle has not moved within a predetermined time interval. Determining that the first container transport vehicle has not moved within the predetermined time interval may include using a second container transport vehicle to determine that the second container transport vehicle has not moved within the predetermined time interval.

[0048] In one embodiment, the method may further include initiating an emergency stop of the second container transport vehicle after determining that the deceleration is higher than a predetermined threshold using the second container transport vehicle.

[0049] In one embodiment, the method may further include increasing the thrust on the first container transport vehicle when it is determined that the first container transport vehicle is moving using the second container transport vehicle.

[0050] In a second aspect, the invention also relates to an automated storage and retrieval system, comprising: a plurality of container transport vehicles on a track system arranged at least partially across the top of a frame structure of the automated storage and retrieval system, the plurality of container transport vehicles being operable on the track system to transport storage containers; and a control system adapted to communicate with a local controller in each of the transport vehicles, the control system also being adapted to perform the following steps:

[0051] Instruct the first container transport vehicle to move in a first direction toward a grid cell designated as a first target location on the track system;

[0052] The second container transport vehicle is instructed to move toward the first target location in a first direction, such that the second container transport vehicle physically contacts the first container transport vehicle, and after contacting the first container transport vehicle, the second container transport vehicle applies a thrust to the first container transport vehicle to maintain physical contact.

[0053] Instructing the application of thrust may include instructing the second container handling vehicle to apply a non-thrust force exceeding the default movement required for the second container handling vehicle. The non-thrust force may exceed 2-25%, preferably 2-10%, or most preferably 3-8%.

[0054] Thrust and non-thrust can be determined by measuring the power usage of the second container handling vehicle.

[0055] Instructing the application of thrust may include instructing the second container vehicle to move according to a motion vector exceeding that of the first container handling vehicle in the first direction. The corresponding motion vector of the first container handling vehicle in the first direction may exceed this vector by 2-25%, preferably 2-10%, or most preferably 3-8%.

[0056] The second container handling vehicle may be adapted to stop applying thrust to the first container handling vehicle after determining that the first container handling vehicle has not moved within a predetermined time interval.

[0057] The second container handling vehicle can be adapted to determine that the first container handling vehicle did not move within the predetermined time interval by determining that the second container handling vehicle did not move within the predetermined time interval.

[0058] In one embodiment, the system can also be adapted to initiate an emergency stop of the second container transport vehicle after determining that the deceleration is higher than a predetermined threshold using the second container transport vehicle.

[0059] The second container handling vehicle may be adapted to increase the thrust on the first container handling vehicle when it is determined that the first container handling vehicle is moving.

[0060] The contact area between the first container handling vehicle and the second container handling vehicle can be provided with a low-friction protective surface.

[0061] In a third aspect, the present invention also relates to a computer program product for the aforementioned control system, wherein the computer program product includes instructions that, when executed on the control system, perform the aforementioned method. Attached Figure Description

[0062] The following figures are provided to aid in understanding the present invention. The figures illustrate embodiments of the invention, which will now be described by way of example only, wherein:

[0063] Figure 1 is a perspective view of the framework structure of an existing automated storage and retrieval system.

[0064] Figure 2 is a perspective view of a prior art container handling vehicle having a centrally located cavity for carrying storage containers therein.

[0065] Figure 3 is a perspective view of a prior art container handling vehicle having a cantilever for supporting storage containers underneath.

[0066] Figure 4 is a perspective view of a prior art container handling vehicle having a cantilever for supporting storage containers underneath.

[0067] Figures 5a to 5d are schematic diagrams of the prior art.

[0068] Figures 6a to 6d This is a schematic diagram of a method according to an embodiment of the present invention.

[0069] Figures 7a to 7c This is a perspective view of a system according to an embodiment of the present invention.

[0070] Figures 8a to 8c This is a perspective view of a system according to an embodiment of the present invention. Detailed Implementation

[0071] In the following, embodiments of the invention will be discussed in more detail with reference to the accompanying drawings. However, it should be understood that the drawings are not intended to limit the invention to the subject matter depicted therein.

[0072] The frame structure 100 of the automatic storage and retrieval system 1 is constructed according to the prior art frame structure 100 described above in conjunction with Figures 1 to 3, namely, a plurality of upright members 102 and a plurality of horizontal members 103 supported by the upright members 102, and the frame structure 100 further includes a first upper track system 108 in the X and Y directions.

[0073] The frame structure 100 also includes storage compartments arranged in the form of storage columns 105 between the members 102 and 103, wherein storage containers 106 can be stacked in the storage columns 105 in the form of stacks 107.

[0074] The frame structure 100 can be of any size. In particular, it should be understood that the frame structure can be much wider and / or much longer and / or much deeper than disclosed in Figure 1. For example, the frame structure 100 can have a horizontal range of more than 700 × 700 columns and a storage depth of more than 12 containers.

[0075] This invention relates to a system and method that allows multiple container handling vehicles to form a "queue," i.e., multiple container handling vehicles are arranged in series or in a queue and configured to move in series with each other. This saves time around the port, thereby avoiding the need to wait for confirmation messages and instructions to move. Compared to the prior art methods described with reference to Figures 5a to 5d, the method of the present invention saves approximately 1.5 seconds per operation. Due to the sufficient capacity of the container handling vehicles, the method of the present invention saves 450 seconds per hour for a port rated to receive 300 storage containers per hour, which provides a 12.5% ​​increase in efficiency.

[0076] Now refer to Figures 6a to 6d , Figures 7a to 7c and Figures 8a to 8c An embodiment of the automatic storage and retrieval system according to the present invention will be discussed in more detail.

[0077] Figures 6a to 6d The diagram schematically illustrates a situation where both the first container transport vehicle 501 and the second container transport vehicle 502 use the grid cell TP1 as their designated first target location.

[0078] exist Figure 6a In the middle, the first container handling vehicle 501 is instructed to move toward TP1 in the first direction.

[0079] Then Figure 6b In the process, the second container transport vehicle 502 is instructed to move toward TP1 in a first direction to make physical contact with the first container transport vehicle 501. After contact, the second container transport vehicle 502 applies a thrust to the first container transport vehicle 501, that is, pushes the first container transport vehicle 501 to maintain physical contact.

[0080] exist Figure 6c In the process, when the first container transport vehicle 501 finishes in TP1, it begins to move out of TP1, and the second container transport vehicle 502 follows by applying a thrust to contact the first container transport vehicle 501.

[0081] exist Figure 6dWhen the first container handling vehicle 501 is outside TP1, the second container handling vehicle 502 is ready in TP1. The second container handling vehicle 502 moves the first container handling vehicle 501 without having to wait for any confirmation message and / or instructions to move.

[0082] Figure 7a A second container transport vehicle 502 is shown moving in a first direction toward a first target location TP1. TP1 in this example is the location of the first container transport vehicle 501. TP1 is also a storage column 105 from which both the first container transport vehicle 501 and the second container transport vehicle 502 have been instructed to remove storage containers (e.g., as part of an excavation process). TP1 could also be a port location.

[0083] Figure 7b The diagram shows a second container transport vehicle 502 physically contacting a first container transport vehicle 501. After contacting the first container transport vehicle 501, the second container transport vehicle 502 applies a thrust, i.e., pushes against the first container transport vehicle 501. The second container transport vehicle 502 may continue to apply the thrust indefinitely, but if the first container transport vehicle 501 does not move within a timeout period, the thrust will cease to prevent burnout / damage to the electronics.

[0084] Figure 7c The diagram illustrates a second container transport vehicle 502 moving alongside the first container transport vehicle 501 as the first container transport vehicle begins to move away from TP1. The second container transport vehicle 502 can be configured to determine that the first container transport vehicle 501 is moving. Upon determining that the first container transport vehicle 501 is moving, the second container transport vehicle 502 can increase the thrust on the first container transport vehicle 501. The second container transport vehicle 502 can also apply a smaller thrust when stationary and waiting for the first container transport vehicle 501 to move. When determining that the first container transport vehicle 501 is moving, the second container transport vehicle 502 can use a larger force to follow the first container transport vehicle 501 to maintain contact and avoid collisions. Applying a smaller force while waiting avoids burning out electronics and / or wearing out mechanical parts. Whether the first container transport vehicle 501 is moving can be determined based on changes in the power consumption of the second container transport vehicle 502. Alternatively, the second container transport vehicle 502 may be provided with a pressure sensor in the contact area between the first container transport vehicle 501 and the second container transport vehicle 502, the pressure sensor measuring the applied force and / or the change in the applied force.

[0085] In one embodiment, the second container handling vehicle 502 is instructed to apply a thrust exceeding the non-thrust force required for its movement. The non-thrust force may be the inertia that must be overcome before the second container handling vehicle 502 begins to move along the track system from rest, or the force required to keep the second container handling vehicle 502 moving along the track system. The non-thrust force may be provided by the total weight of the second container handling device 502 and / or other drive configurations of the second container handling device 502.

[0086] When thrust is defined as a force exceeding non-thrust, the second container transport vehicle 502 can dynamically adjust the thrust based on feedback, keeping the amount of thrust within a tight range that only lightly pushes the first container transport device 501, and adjusting the output of the second container transport vehicle as the first container transport device moves to remain within this range. The second container transport vehicle 502 can determine thrust and non-thrust by measuring its power consumption. Power consumption can provide feedback to dynamically adjust the amount of thrust.

[0087] Non-thrust can be exceeded by 2-25%, 2-10%, or 3-8% to provide the necessary thrust.

[0088] In another embodiment, the thrust is defined by instructing the second container transport vehicle 502 to move according to the motion vector in the direction of the first container transport vehicle 501. The motion vector of the second container transport vehicle 502 exceeds the corresponding motion vector of the first container transport vehicle 501.

[0089] The acceleration of the second container handling vehicle 502 is greater than the acceleration of the first container handling vehicle 501.

[0090] The speed of the second container transport vehicle 502 is greater than the speed of the first container transport vehicle 501.

[0091] The deceleration of the second container transport vehicle 502 is less than the deceleration of the first container transport vehicle 501.

[0092] The motion vector of the first container handling vehicle 501 in the first direction can be greater than 2-25%, 2-10%, or 3-8% to provide the necessary thrust.

[0093] The first container transport vehicle 501 and the second container transport vehicle 502 are configured to allow more unintended behavior when driven in a queue than when driven alone, before reporting an error to the control system. Furthermore, if the first container transport vehicle 501 malfunctions, the second container transport vehicle 502 should be instructed by the control system to initiate an emergency stop. Errors in the communication system, delays in the control system, collisions on the track system, etc., may prevent the control system from instructing the container transport vehicle 502 to stop. Therefore, the second container transport vehicle 502 can be adapted to initiate an emergency stop after determining a deceleration exceeding a predetermined threshold using the second container transport vehicle 502. This determination can be based on the measurement of thrust using power usage, external sensors, or other force-measuring devices.

[0094] Figures 7a to 7c Container transport vehicles 501 and 502, which are cantilevered 301 and move in the X direction, and cavity-type 201 and move in the X or Y direction, are shown. To prevent damage to the container transport vehicles 501 and 502, for example, due to metal debris that terminates in the tracks or electronic components, the contact surface 700 is provided with a low-friction protective surface, such as a sliding surface.

[0095] Figures 8a to 8c The diagram illustrates the identical motion of two cantilevered container handling vehicles 501 and 502 moving in the Y direction. They are otherwise similar. Figures 7a to 7c sequence.

[0096] In one embodiment, the queue of container transport vehicles may include more than two container transport vehicles 501, 502. In this case, a third container transport vehicle applies greater thrust than the second container transport vehicle 502, a fourth container transport vehicle applies greater thrust than the third container transport vehicle, and so on for each container transport vehicle further back in the queue.

[0097] Multiple container handling vehicles can also queue up to travel the initial distance, then split into several smaller queues. Container handling vehicles ahead of the separated vehicles can continue at their current speed, while those behind will have to slow down. After the separation, the smaller queues will be reconfigured and continue as described above.

[0098] In the foregoing description, various aspects of the container handling vehicle and automated storage and retrieval system according to the present invention have been described with reference to illustrative embodiments. Specific figures, systems, and configurations have been set forth for purposes of explanation in order to provide a full understanding of the system and its operation. However, this specification is not intended to be interpreted in a limiting sense. Various modifications and variations of the illustrative embodiments, as well as other embodiments of the system, that will be apparent to those skilled in the art to which the disclosed subject matter pertains, are considered to fall within the scope of these claims.

[0099] List of reference numerals in the attached figures

[0100] Prior art (Figures 1 to 4):

[0101] 1. Existing automated storage and retrieval systems

[0102] 100 frame structure

[0103] 102. Upright members of the frame structure

[0104] Horizontal members of the 103 frame structure

[0105] 104 storage grid

[0106] 105 storage columns

[0107] 106 storage containers

[0108] Specific location of 106' storage container

[0109] 107 stacks

[0110] 108 orbital system

[0111] 110 Parallel track in the first direction (X)

[0112] 110a First orbit in the first direction (X)

[0113] 110b Second orbit in the first direction (X)

[0114] 111 Parallel track in the second direction (Y)

[0115] 111a First track in the second direction (Y)

[0116] 111b Second orbit in the second direction (Y)

[0117] 112 Access Opening

[0118] 119 First Port Column

[0119] 120 Second Port Column

[0120] 121 Control System

[0121] 201 Prior art storage container vehicles

[0122] 201a storage container vehicle 201 body

[0123] 201b Drive unit / wheel arrangement, first direction (X)

[0124] 201c drive unit / wheel arrangement, second direction (Y)

[0125] 301 Prior art cantilevered storage container vehicles

[0126] 301a storage container vehicle body 301

[0127] 301b Drive device in the first direction (X)

[0128] 301c Drive device in the second direction (Y)

[0129] 304 clamping device

[0130] 401 Prior art storage container vehicle 401a Storage container vehicle 401 body 401b Drive unit / wheel arrangement, first direction (X) 401c Drive unit / wheel arrangement, second direction (Y) X first direction

[0131] Y second direction

[0132] Z Third-party direction

[0133] Figures 5 to 8:

[0134] TP1 target location

[0135] 501 First Container Handling Vehicle

[0136] 502 Second Container Handling Vehicle

[0137] 504 storage grid 700 sliding surface

Claims

1. A method for controlling the movement of a plurality of container handling vehicles (201, 301, 401) on a track system (108), said track system being arranged to at least partially span the top of a frame structure (100) of an automated storage and retrieval system (1), said plurality of container handling vehicles (201, 301, 401) being operable on said track system (108) to handle storage containers (106), wherein, The control system (121) performs the following steps by communicating with the local controller in each container handling vehicle (201, 301, 401): Instruct the first container transport vehicle (501) to move in a first direction toward the grid cell designated as the first target position (TP1) on the track system (108); The second container transport vehicle (502) is instructed to move toward the first target location (TP1) in the first direction, such that the second container transport vehicle (502) physically contacts the first container transport vehicle (501), and the second container transport vehicle (502) applies a thrust to the first container transport vehicle (501) after contacting the first container transport vehicle to maintain physical contact.

2. The method according to claim 1, wherein, Instructing to apply thrust includes instructing the second container handling vehicle to apply a non-thrust force exceeding the force required for the second container handling vehicle to move.

3. The method according to claim 2, wherein, The non-thrust is exceeded by 2-25%.

4. The method according to claim 2 or 3, wherein, The thrust and the non-thrust are determined by measuring the power usage of the second container transport vehicle.

5. The method according to any one of claims 1 to 3, wherein, Instructing the application of thrust includes instructing the second container handling vehicle to move according to a motion vector exceeding the corresponding motion vector of the first container handling vehicle in the first direction.

6. The method according to claim 5, wherein, The corresponding motion vector of the first container transport vehicle in the first direction is exceeded by 2-25%.

7. The method according to any one of claims 1 to 3, wherein, The method further includes stopping the application of the thrust to the first container transport vehicle after determining that the first container transport vehicle has not moved within a predetermined time interval.

8. The method according to claim 7, wherein, Determining that the first container transport vehicle did not move during the predetermined time interval includes determining that the second container transport vehicle did not move during the predetermined time interval using the second container transport vehicle.

9. The method according to any one of claims 1 to 3, wherein, The method further includes initiating an emergency stop of the second container transport vehicle after determining that the deceleration is higher than a predetermined threshold using the second container transport vehicle.

10. The method according to any one of claims 1 to 3, wherein, The method further includes increasing the thrust on the first container transport vehicle when it is determined using the second container transport vehicle that the first container transport vehicle is moving.

11. The method according to claim 3, wherein, The non-thrust is exceeded by 2-10%.

12. The method according to claim 11, wherein, The non-thrust is exceeded by 3-8%.

13. The method according to claim 6, wherein, The corresponding motion vector of the first container transport vehicle in the first direction is exceeded by 2-10%.

14. The method according to claim 13, wherein, The corresponding motion vector of the first container transport vehicle in the first direction is exceeded by 3-8%.

15. An automatic storage and retrieval system (1), comprising: A plurality of container handling vehicles (201, 301, 401) on a track system (108) arranged at least partially across the top of the frame structure (100) of the automated storage and retrieval system (1), the plurality of container handling vehicles (201, 301, 401) being operable on the track system (108) to handle storage containers (106); and a control system (121) adapted to communicate with a local controller in each container handling vehicle (201, 301, 401), the control system (121) being further adapted to perform the following steps: Instruct the first container transport vehicle (501) to move in a first direction toward the grid cell designated as the first target position (TP1) on the track system (108); The second container transport vehicle (502) is instructed to move toward the first target location (TP1) in the first direction, such that the second container transport vehicle physically contacts the first container transport vehicle, and the second container transport vehicle applies a thrust on the first container transport vehicle after contacting the first container transport vehicle to maintain physical contact.

16. The automatic storage and retrieval system according to claim 15, wherein, Instructing to apply thrust includes instructing the second container handling vehicle to apply a non-thrust force exceeding the default movement required for the second container handling vehicle.

17. The automatic storage and retrieval system according to claim 16, wherein, The non-thrust is exceeded by 2-25%.

18. The automatic storage and retrieval system according to claim 16 or 17, wherein, The thrust and the non-thrust are determined by measuring the power usage of the second container transport vehicle.

19. The automatic storage and retrieval system according to any one of claims 15 to 17, wherein, Instructing the application of thrust includes instructing the second container handling vehicle to move according to a motion vector exceeding the corresponding motion vector of the first container handling vehicle in the first direction.

20. The automatic storage and retrieval system according to claim 19, wherein, The corresponding motion vector of the first container transport vehicle in the first direction is exceeded by 2-25%.

21. The automatic storage and retrieval system according to any one of claims 15 to 17, wherein, The second container transport vehicle is adapted to stop applying the thrust to the first container transport vehicle after determining that the first container transport vehicle has not moved within a predetermined time interval.

22. The automatic storage and retrieval system according to claim 21, wherein, The second container transport vehicle is adapted to determine that the first container transport vehicle did not move during the predetermined time interval by determining that the second container transport vehicle did not move during the predetermined time interval.

23. The automatic storage and retrieval system according to any one of claims 15 to 17, wherein, The automatic storage and retrieval system is also adapted to initiate an emergency stop of the second container transport vehicle after determining that the deceleration is higher than a predetermined threshold using the second container transport vehicle.

24. The automatic storage and retrieval system according to any one of claims 15 to 17, wherein, The second container transport vehicle is adapted to increase the thrust on the first container transport vehicle when it is determined that the first container transport vehicle is moving.

25. The automatic storage and retrieval system according to any one of claims 15 to 17, wherein, The contact area between the first container handling vehicle and the second container handling vehicle is provided with a low-friction protective surface.

26. The automatic storage and retrieval system according to claim 17, wherein, The non-thrust is exceeded by 2-10%.

27. The automatic storage and retrieval system according to claim 26, wherein, The non-thrust is exceeded by 3-8%.

28. The automatic storage and retrieval system according to claim 20, wherein, The corresponding motion vector of the first container transport vehicle in the first direction is exceeded by 2-10%.

29. The automatic storage and retrieval system according to claim 28, wherein, The corresponding motion vector of the first container transport vehicle in the first direction is exceeded by 3-8%.

30. A computer program product for a control system (121) in an automatic storage and retrieval system, wherein, The computer program product includes instructions that, when executed on the control system, perform the method according to any one of claims 1 to 14.

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