SYSTEM, METHOD AND MAIN CONTROL SYSTEM FOR HANDLING MALFUNCTIONING VEHICLES IN AN AUTOMATED STORAGE AND RETRIEVAL SYSTEM COMPRISING A RAIL SYSTEM

An automated storage and retrieval system includes a rail system with perpendicular tracks in X and Y direction. The storage and retrieval system includes a plurality of remotely operated container handling vehicles configured to move laterally on the rail system; and a main control system using a first communication system for communicating with the plurality of remotely operated container handling vehicles. The main control system monitors and controls the movement of the plurality of container handling vehicles via the first communication system. At least one service vehicle is movable on the rail system. The at least one service vehicle is configured to bring a malfunctioning remotely operated container handling vehicle to a service area outside of the rail system where the remotely operated container handling vehicles operate. The system further includes a secondary control system using a second communication system. The second communication system is independent of the main communication system. The secondary control system is communicating with the at least one service vehicle on the rail system such as to monitor and control the movement of the at least one service vehicle.

TECHNICAL FIELD

The present invention relates to a method for handling malfunctioning vehicles on a rail system constituting part of a storage and retrieval system configured to store a plurality of stacks of storage containers, a storage and retrieval system and a control system carrying out the method, and a main control system for an automated storage and retrieval system.

BACKGROUND AND PRIOR ART

FIG.1Adiscloses a typical prior art automated storage and retrieval system1with a framework structure100.

The framework structure100comprises a plurality of upright members102and optionally a plurality of horizontal members103supporting the upright members102. The members102,103may typically be made of metal, e.g. extruded aluminum profiles.

The framework structure100defines a storage grid104comprising storage columns105arranged in rows, in which storage columns105storage containers106(also known as bins) are stacked one on top of another to form stacks107.

Each storage container106may typically hold a plurality of product items (not shown), and the product items within a storage container106may be identical or may be of different product types depending on the application.

The storage grid104guards against horizontal movement of the storage containers106in the stacks107, and guides vertical movement of the storage containers106, but does normally not otherwise support the storage containers106when stacked.

The automated storage and retrieval system1comprises a rail system108arranged in a grid pattern across the top of the storage104, on which rail system108a plurality of container handling vehicles250(as exemplified inFIG.1C) are operated to raise storage containers106from, and lower storage containers106into, the storage columns105, and also to transport the storage containers106above the storage columns105. The horizontal extent of one of the grid cells122constituting the grid pattern is inFIG.1Amarked by thick lines.

The rail system108comprises a first set of parallel rails110arranged to guide movement of the container handling vehicles250in a first direction X across the top of the frame structure100, and a second set of parallel rails111arranged perpendicular to the first set of rails110to guide movement of the container handling vehicles250in a second direction Y which is perpendicular to the first direction X. In this way, the rail system108defines grid columns above which the container handling vehicles250can move laterally above the storage columns105, i.e. in a plane which is parallel to the horizontal X-Y plane.

The rail system108may be a single rail system or a double rail system as is shown inFIG.1B. The latter rail configuration allows a container handling vehicle250having a footprint generally corresponding to the lateral area defined by a grid cell122to travel along a row of grid columns even if another container handling vehicle250is positioned above a grid cell neighboring that row. Both the single and double rail system, or a combination comprising a single and double rail arrangement in a single rail system108, forms a grid pattern in the horizontal plane P comprising a plurality of rectangular and uniform grid locations or grid cells122, where each grid cell122comprises a grid opening115being delimited by a pair of neighboring rails110a,110bof the first set of rails110and a pair of neighboring rails111a,111bof the second set of rails111.

Consequently, rails110aand110bform pairs of rails defining parallel rows of grid cells running in the X direction, and rails111aand111bform pairs of rails defining parallel rows of grid cells running in the Y direction.

As shown inFIG.1B, each grid cell122(indicated by a dashed box) has a width Wcwhich is typically within the interval of 30 to 150 cm, and a length Lcwhich is typically within the interval of 50 to 200 cm. Each grid opening115has a width Woand a length Lowhich is typically 2 to 10 cm less than the width Wcand the length Lcof the grid cell122.

FIG.1Cdiscloses a prior art container handling vehicle250operating the system1disclosed inFIG.1A. Each prior art container handling vehicle250comprises a vehicle body252and a wheel arrangement251of eight wheels, where a first set of four wheels enable the lateral movement of the container handling vehicles250in the X direction and a second set of the remaining four wheels enable the lateral movement in the Y direction. One or both sets of wheels in the wheel arrangement251can be lifted and lowered, so that the first set of wheels and/or the second set of wheels can be engaged with the respective set of rails110,111at any one time.

Each prior art container handling vehicle250also comprises a lifting device (not shown) for vertical transportation of storage containers106, e.g. raising a storage container106from, and lowering a storage container106into, a storage column105. The lifting device may comprise one or more gripping/engaging devices which are adapted to engage a storage container106, and which gripping/engaging devices can be lowered from the vehicle250so that the position of the gripping/engaging devices with respect to the vehicle can be adjusted in a third direction Z which is orthogonal the first direction X and the second direction Y.

Conventionally, and also for the purpose of this application, Z=1 identifies the uppermost layer of the grid104, i.e. the layer immediately below the rail system108, Z=2 the second layer below the rail system108, Z=3 the third layer etc. In the exemplary prior art grid104disclosed inFIG.1A, Z=8 identifies the lowermost, bottom layer of the grid104. Consequently, as an example, and using the Cartesian coordinate system X, Y, Z indicated inFIG.1A, the storage container identified as106′ inFIG.1Acan be said to occupy grid location or cell X=10, Y=2, Z=3. The container handling vehicles250can be said to travel in layer Z=0 and each grid column can be identified by its X and Y coordinates.

Each container handling vehicle250comprises a storage compartment or space (not shown) for receiving and stowing a storage container106when transporting the storage container106across the rail system108. The storage space may comprise a cavity arranged centrally within the vehicle body252, e.g. as is described in WO2014/090684A1, the contents of which are incorporated herein by reference.

The container handling vehicles250may have a footprint, i.e. an extent in the X and Y directions, which is generally equal to the lateral extent of a grid cell122, i.e. the extent of a grid cell122in the X and Y directions, e.g. as is described in WO2015/193278A1, the contents of which are incorporated herein by reference. The term “lateral” used herein may mean “horizontal”.

Alternatively, the container handling vehicles may have a footprint which is larger than the lateral extent of (lateral area defined by) a grid column105, e.g. as is disclosed in WO2014/090684A1.

In the X and Y directions, neighboring grid cells are arranged in contact with each other such that there is no space there-between.

In a storage grid104, a majority of the grid columns are storage columns105, i.e. grid columns105where storage containers106are stored in stacks107. However, a grid104normally has at least one grid column which is used not for storing storage containers106, but which comprises a location where the container handling vehicles250can drop off and/or pick up storage containers106so that they can be transported to a second location (not shown) where the storage containers106can be accessed from outside of the grid104or transferred out of or into the grid104. Within the art, such a location is normally referred to as a “port” and the grid column in which the port is located may be referred to as a “delivery column”119,120. The drop-off and pick-up ports of the container handling vehicles are referred to as the “upper ports of a delivery column”119,120. While the opposite end of the delivery column is referred to as the “lower ports of a delivery column”.

The storage grid104inFIG.1Acomprises two delivery columns119and120. The first delivery column119may for example comprise a dedicated drop-off port where the container handling vehicles250can drop off storage containers106to be transported through the delivery column119and further to an access or a transfer station, and the second delivery column120may comprise a dedicated pick-up port where the container handling vehicles250can pick up storage containers106that have been transported through the delivery column120from an access or a transfer station. Each of the ports of the first and second delivery column may comprise a port suitable for both pick up and drop of storage containers.

The second location may typically be a picking or a stocking station where product items are removed from or positioned into the storage containers106. In a picking or a stocking station, the storage containers106are normally never removed from the automated storage and retrieval system1but are returned into the storage grid104once accessed. For transfer of storage containers out or into the storage grid104, there are also lower ports provided in a delivery column, such lower ports are e.g. for transferring storage containers106to another storage facility (e.g. to another storage grid), directly to a transport vehicle (e.g. a train or a lorry), or to a production facility.

A conveyor system may also be arranged to transfer storage containers between different storage grids, e.g. as is described in WO2014/075937A1, the contents of which are incorporated herein by reference.

When a storage container106stored in the storage grid104disclosed inFIG.1Ais to be accessed, one of the container handling vehicles250is instructed to retrieve the target storage container106from its position in the grid104and transport it to or through the transfer column119. This operation involves moving the container handling vehicle250to a grid location above the storage column105in which the target storage container106is positioned, retrieving the storage container106from the storage column105using the container handling vehicle's lifting device (not shown), and transporting the storage container106to the transfer column119. If the target storage container106is located deep within a stack107, i.e. with one or a plurality of other storage containers positioned above the target storage container106, the operation also involves temporarily moving the above-positioned storage containers prior to lifting the target storage container106from the storage column105. This step, which is sometimes referred to as “digging” within the art, may be performed with the same container handling vehicle250that is subsequently used for transporting the target storage container106to the transfer column, or with one or a plurality of other cooperating container handling vehicles250. Alternatively, or in addition, the automated storage and retrieval system1may have container handling vehicles specifically dedicated to the task of temporarily removing storage containers106from a storage column105. Once the target storage container106has been removed from the storage column105, the temporarily removed storage containers can be repositioned into the original storage column105. However, the removed storage containers may alternatively be relocated to other storage columns105.

When a storage container106is to be stored in the grid104, one of the container handling vehicles250is instructed to pick up the storage container106from the transfer column120and to transport it to a grid location above the storage column105where it is to be stored. After any storage containers positioned at or above the target position within the storage column stack107have been removed, the container handling vehicle250positions the storage container106at the desired position. The removed storage containers may then be lowered back into the storage column105or relocated to other storage columns105.

For monitoring and controlling the automated storage and retrieval system1so that a desired storage container106can be delivered to the desired location at the desired time without the container handling vehicles250colliding with each other, the automated storage and retrieval system1comprises a control system109, which typically is computerized and comprises a database for monitoring and controlling e.g. the location of the respective storage containers106within the storage grid104, the content of each storage container106and the movement of the container handling vehicles250.

A problem associated with known automated storage and retrieval systems1is that it is challenging for personnel to access the rail system108for carrying out inspection, or to carry out maintenance of or to remove malfunctioning container handling vehicles250.

Another important problem with maintenance or removal of malfunctioning vehicles250is that a complete shutdown of the system1is needed for the personnel to access with low or zero risk of injury. In particular for large systems1, for example systems1with in excess of 500 vehicles in operation simultaneously, a complete shutdown is highly undesired due to significant cost for the operator.

Prior art includes WO2015/140216 A1 disclosing a service robot which operates under the same control system as the container robots. WO2015/140216A1 discloses a service vehicle for cleaning the grid and for inspection of the grid. The service vehicle is arranged with a releasable latching mechanism for docking with a malfunctioning container handling vehicle. In addition, the publication suggests that the service vehicle may be arranged with a seat for carrying a user to inspect and carry out maintenance. This personnel carrying version of the service vehicle may be manually operated by the user, or alternatively remotely controlled by the control system.

For these operations to happen safely it is necessary to stop all container handling vehicles on the grid before the user is allowed access. The higher the number of robotic load handlers in use and the larger the grid, the higher the likelihood of faults occurring and an increased consequence of each fault, due to the number of units which have to be stopped.

It is an objective of the invention to provide a malfunctioning container handling vehicle without shutting down the system.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention.

It is described an automated storage and retrieval system comprising a rail system with perpendicular tracks in X and Y direction, wherein the storage and retrieval system comprises:a plurality of remotely operated container handling vehicles configured to move laterally on the rail system; anda main control system using a first communication system for communicating with the plurality of remotely operated container handling vehicles; wherein the main control system monitors and controls the movement of the plurality of container handling vehicles via the first communication system;at least one service vehicle movable on the rail system, wherein the at least one service vehicle is configured to bring a malfunctioning remotely operated container handling vehicle to a service area outside of the rail system where the remotely operated container handling vehicles operate;
wherein the system further comprises:a second control system using a second communication system, wherein the second communication system is independent of the main communication system, and wherein the secondary control system is communicating with the at least one service vehicle on the rail system such as to monitor and control the movement of the at least one service vehicle.

The main control system may thus monitor and control the movement of the plurality of container handling vehicles via the first communication system.

The second control system may thus monitor and control the movement of the at least one service vehicle via the second communication system.

The term independent, i.e. that the second communication system is independent of the first communication system, shall be understood as the two communication systems which cannot interfere with one another. However, the main control system and secondary control system may operate under a same master controller.

Both the first communication system and the second communication system preferably operate using wireless communication.

In an aspect, the main control system may be configured to perform, by wireless data communication, at least the following steps:

A. determining an anomaly in an operational condition of a vehicle on the rail system,
B. registering the vehicle with the anomalous operational condition as a malfunctioning vehicle,
C. registering a position of the malfunctioning vehicle relative to the supporting rail system.

A malfunctioning vehicle may be a vehicle which is partly malfunctioning or a vehicle which is not functioning at all. A vehicle not functioning at all may e.g. have completely stopped and/or communication with the first communication system may have been interrupted for some reason.

The main control system is further configured to perform:

D. setting up a two-dimensional exclusion zone extending from the malfunctioning vehicle to a position of the service vehicle.

The exclusion zone may be set up along the shortest route to the malfunction vehicle. Alternatively, the exclusion zone may not be the shortest route but selected based on other parameters. For example, the exclusion zone may be along a perimeter of the rail system, e.g., to maintain an as large as possible and an as effective as possible working area for the vehicles to operate in. In other words, the exclusion zone might take up more overall area of the working area but that might still result in more efficient operation.

The main control system may further be configured to perform:

E. updating a movement pattern of the plurality of remotely operated vehicles by instructing any remotely operated vehicles positioned within the two-dimensional exclusion zone to move outside of the two-dimensional exclusion zone and avoiding entry of any of the remaining remotely operated vehicles into the two-dimensional exclusion zone.

Therefore, the remotely operated vehicles that are currently in the exclusion zone when the main control system updates the movement pattern and sets up an exclusion zone, are routed to a position outside the exclusion zone. Such re-routing of the remotely operated vehicles ensure that remotely operated vehicles do not represent obstacles to the service vehicle. It also allows these remotely operated vehicles to perform container handling operations whilst the exclusion zone is in effect. In other words, any remotely operated vehicle currently in grid cells that are to form part of an exclusion zone are re-rerouted to grid cells outside of the planned exclusion zone. Therefore, the remotely operated vehicles will need to be identified and moved out of the way before the occupied cells forms part of a planned exclusion zone.

When the main control system has performed the above steps, the secondary control system may be configured to perform, by wireless data communication, at least the following step:

F. operating the at least one service vehicle to move from an initial position to a position next to the malfunctioning vehicle along the exclusion zone.

The first communication system and the second communication system may be the same communication system or different communication systems. Such communication system may include WiFi, light (e.g. Lifi) etc.

The first communication system and the second communication system may operate with different frequencies.

The first communication system and the second communication system may have different coding and de-coding processes.

For example, the first communication system is wireless fidelity (WiFi) and the second communication system is light fidelity (LiFi).

The second communication system maybe automatically or manually operated. In the event of manual operation, an operator may remotely control the service vehicle along the exclusion zone using a remote control or similar.

The service vehicle may comprise wheels which are guided for movement along the rails in X and Y directions.

The service vehicle may comprise caterpillar tracks for movement over a top surface of the rail system independent of the X and Y directions of the rail system.

An initial position of the service vehicle may be in a service area outside of the rail system where the remotely operated vehicles operate.

If the service vehicle comprises wheels, the service area preferably comprises rails connected to the rail system.

In one embodiment, the rail system is at a top level of a storage grid.

In one embodiment, the rail system is a delivery rail system.

It is further described a method for handling malfunctioning vehicles on a rail system wherein the storage and retrieval system comprises:a plurality of remotely operated container handling vehicles configured to move laterally on the rail system; anda main control system using a first communication system for communicating with the plurality of vehicles wirelessly, wherein the main control system monitors and controls the movement of the plurality of container handling vehicles via the first communication system;at least one service vehicle positioned at an initial position, wherein the service vehicle is movable on the rail system, and wherein the at least one service vehicle is configured to bring a malfunctioning remotely operated container handling vehicle to a service area outside of the rail system where the remotely operated container handling vehicles operate;a secondary control system, using a second communication system which is independent of the main control system for communicating with the at least one service vehicle on the rail system wirelessly, and wherein the secondary control system monitors and controls the movement of the at least one service vehicle; the main control system performs at least the following steps:
A. determining an anomaly in an operational condition of a vehicle on the rail system,
B. registering the vehicle with the anomalous operational condition as a malfunctioning vehicle,
C. registering a position of the malfunctioning vehicle relative to the supporting rail system.

The method may further comprise utilizing the main control system to perform:

D. setting up a two-dimensional exclusion zone extending from the malfunctioning vehicle to the position of the service vehicle.

The method may further comprise utilizing the main control system to perform:

E. updating movement pattern of the plurality of remotely operated vehicles outside the two-dimensional exclusion zone such that entrance into the two-dimensional exclusion zone is avoided.

The method may further comprise, when the main control system has performed the above steps, the secondary control system performs by wireless data communication at least the following step:

F. operating the at least one service vehicle to move from its initial position to the position where the malfunctioning vehicle is halted along the exclusion zone.

It is further described a main control system for an automated storage and retrieval system, the automated storage and retrieval system comprising:a rail system with horizontal tracks extending in perpendicular X and Y directions;a plurality of remotely operated container handling vehicles configured to operate on the rail system;a service vehicle; anda secondary control system for the service vehicle wherein the secondary control system is communicating with the at least one service vehicle on the rail system such as to monitor and control the movement of the at least one service vehicle, and wherein the at least one service vehicle is configured to bring a malfunctioning remotely operated container handling vehicle to a service area outside of the rail system where the remotely operated container handling vehicles operate, wherein the main control system is configured to route the plurality of remotely operated vehicles across a working zone of the rail system, the main control system further being configured to detect if a remotely operated vehicle is malfunctioning, and if it is, the main control system may be configured to:reconfigure the working zone to divide off an exclusion zone, the exclusion zone defining an area of the rail system containing the malfunctioning remotely operated vehicle and providing a path for the service vehicle to reach the malfunctioning remotely operated vehicle;reroute other remotely operated vehicles operating in the exclusion zone and in the reconfigured working zone so that they avoid the area of the rail system defined by the exclusion zone; andhand over control of the area of the rail system in the exclusion zone to the secondary control system.

In one aspect, the automated storage and retrieval system described above comprises the main control system described in the latter.

The main control system may be configured, once the service vehicle has moved out of the exclusion zone of the rail system, to:take back control of the area of the rail system within the exclusion zone from the secondary control system;reconfigure the working zone to include the area of the rail system that was previously in the exclusion zone; andreroute remotely operated vehicles to take account of the increased working zone with the area of the rail system previously in the exclusion zone included as part of the working zone.

In the drawings, the same reference numerals have been used to indicate like parts, elements or features unless otherwise explicitly stated or implicitly understood from the context.

DETAILED DESCRIPTION OF THE INVENTION

In the following, embodiments of the invention will be discussed in more detail with reference to the appended drawings. It should be understood, however, that the drawings are not intended to limit the invention to the subject-matter depicted in the drawings.

With reference toFIG.1the automated storage and retrieval system1comprises a framework structure100which includes a storage grid104of in total 1144 grid cells, where the width and length of the grid104corresponds to the width and length of 143 grid columns. The top layer of the framework structure100is a rail system108onto which a plurality of container handling vehicles250are operated.

The framework structure100may be constructed in accordance with the prior art framework structure100described above, i.e. a plurality of upright members102and a plurality of horizontal members103which are supported by the upright members102.

The rail system108includes parallel rails110,111along the X direction and the Y direction, respectively, arranged across the top of storage columns105. The horizontal area of a grid cell122delimiting the opening into the storage column105may be defined by the distance between adjacent rails110and111, respectively.

InFIG.1, a single grid cell122is marked on the rail system108by thick lines inFIG.1Aand shown in a top view inFIG.1B.

The rail system108allows the container handling vehicles250to move horizontally between different grid locations, where each grid location is associated with a grid cell122.

InFIG.1Athe storage grid104is shown with a height of eight cells. It is understood, however, that the storage grid104can in principle be of any size. In particular, It is understood that storage grid104can be considerably wider and/or longer than disclosed inFIG.1. For example, the grid104may have a horizontal extension of more than 700×700 grid cells122. Also, the grid104can be considerably deeper than disclosed inFIGS.1and2. For example, the storage grid104may have a depth corresponding to a stable107of ten storage containers106or more.

All container handling vehicles250may be controlled by a main control system with a first communication system as indicated with reference numeral109′.

The container handling vehicles250may be of any type known in the art, e.g. any one of the automated container handling vehicles disclosed in WO2014/090684 A1, in NO317366 or in WO2015/193278A1.

FIG.2shows a top view of an automated storage and retrieval system1. The system1comprises three framework structures100a-c, each having a storage grid104with stacks107of storage containers106, a rail system108a-carranged on top of the storage grid104and a service area160a-c. The framework structures100a-care separated by two vehicle blocking barriers125, e.g., walls, arranged between the rail systems108a-c. Each of the barriers125includes one or more passages130a,bin which container handling vehicles250may drive through during normal operation.

InFIG.2a particular situation is depicted where a container handling vehicle240has been labeled malfunctional and brought to a halt at a location on the mid rail system108b.

The service areas160a-cmay be adjacent to a mezzanine outside the boundary of the rail systems108, for supporting the service vehicle20while it is inactive.

InFIG.2, a service area160a-cand a service vehicle20is depicted for each of the rail systems108a-c. However, other configurations may be envisaged such as an arrangement of only one mid service area160b, allowing entrance of a service vehicle20into the mid rail system108b. In case a malfunctioning vehicle240is brought to a halt in the left rail system108aor the right rail system108c, the service vehicle20may, with such a configuration, travel through the respective passage130a,band into the affected rail system108a,c.

A different automated storage and retrieval system1is shown in part inFIG.3A. The upright members102constitute part of a framework structure100onto which a transport rail system108with a plurality of container handling vehicles250are operating.

Below this transport rail system108, near the floor level, another framework structure300is shown which partly extends below some of the storage columns105of the framework structure100. As for the other framework structure100, a plurality of vehicles330,340,350may operate on a rail system308comprising a first set of parallel rails310directed in a first direction X and a second set of parallel rails311directed in a second direction Y perpendicular to the first direction X, thereby forming a grid pattern in the horizontal plane PLcomprising a plurality of rectangular and uniform grid locations or grid cells322. Each grid cell of this lower rail system308comprises a grid opening315being delimited by a pair of neighboring rails310a,310bof the first set of rails310and a pair of neighboring rails311a,311bof the second set of rails311.

The part of the lower rail system308that extends below the storage columns105are aligned such that its grid cells322are in the horizontal plane PLcoincident with the grid cells122of the upper rail system108in the horizontal plane P.

Hence, with this particular alignment of the two rail systems108,308, a storage container106being lowered down into a storage column105by a container handling vehicle250can be received by a delivery vehicle350configured to run on the rail system308and to receive storage containers106down from the storage column105. In other words, the delivery vehicle350is configured to receive storage containers106from above, preferably directly from the container handling vehicle250.

FIG.3Bshows an example of such a vehicle350comprising a wheel assembly351similar to the wheel assembly251described for the prior art container handling vehicle250and a storage container support352for receiving and supporting a storage container106delivered by an above container handling vehicle250.

After having received a storage container106, the delivery vehicle350may drive to an access station adjacent to the rail system308(not shown) for delivery of the storage container106for further handling and shipping.

Hereinafter, the upper and lower rail systems108,308are called the transport rail system108and the delivery rail system308. Likewise, the vehicle shown inFIG.3Bis called a container delivery vehicle350.

FIG.4shows a flow chart400of operation when an anomaly is registered in an operational condition of a vehicle. The flow chart includes the following steps:401: Registering an anomaly in an operational condition of a vehicle.402: Labelling the vehicle as a malfunctioning vehicle240,340.403: Requesting the malfunctioning vehicle240,340to stop or remain still.404: Registering the stop position XS,YSof the malfunctioning vehicle240,340.405: Setting up an exclusion zone225,325on the rail system108,308using the main control system109′ from the stop position of the malfunctioning vehicle240,340and to the position of a service vehicle20.406: Are there operative vehicles within the shutdown zone225,325? If “YES” in step406, a step of:407: Rerouting all of the operating vehicles250,350out of the shutdown zone225,325. If “NO” in step406, a step of:408: Routing a service vehicle20using a secondary control system109″ from an initial position along the exclusion zone225,325for handling of the malfunctioning vehicle240,340.409: Bringing the malfunctioning vehicle240,340using the service vehicle20to a service area160.410: Utilizing the main control system109′ to re-open the exclusion zone225allowing the operative vehicles250to enter the exclusion zone225.

FIGS.5A-5Fshow an example of operational sequence when it is registered that a vehicle is malfunctioning, i.e. an anomaly in the operational condition of a vehicle, and how an exclusion zone on a rail system may be set up, and further the relationship between a first communication system operating the vehicles and a second communication system operating the service vehicle in order for the service vehicle to move from a service area along the exclusion zone to pick up and transport the malfunction vehicle back to the service area.

InFIG.5Athe main control system109′ registers that the container handling vehicle240(denoted X) in cell M12is malfunctioning.

InFIG.5Bthe container handling vehicle250in cell T8has moved to cell R8under instructions from the main control system109′, as indicated by the back end point and front end point of arrow A1. In addition, the container handling vehicle250in cell Q14has moved to cell Q13under instructions from the main control system109′, as indicated by the back end point and front end point of arrow A2.

InFIG.5C, an exclusion zone225(indicated by dashed area) has been created by the main control system109′ from the service area160to the malfunctioning container handling vehicle (X,240). The disclosed exclusion zone225has two cells width and extends all the way through the S and T rows, further to M14and M15and to M12and N12creating a continuous path for the service vehicle20.

The exclusion zone225has been created at the boundary of the rail system108in order to minimize the impact on the remaining container handling vehicles250operating on the rail system108. However, it will be understood that the exclusion zone225can be created anywhere on the rail system108, whatever is most expedient in the specific situation and preferably along a path which minimizes the interruption of the other container handling jobs.

InFIG.5Da service vehicle20has left its initial position in the service area160under control of the secondary control system109″ and occupies cells S5-S6-T5-T6, as indicated by arrow A3.

InFIG.5Ethe service vehicle20has moved to the position of the malfunctioning container handling vehicle X,240(next to cell M12) as indicated by arrow A4, and under control of the second communication system109″.

InFIG.5Fthe service vehicle20has brought the malfunctioning container handling vehicle240,X to the service area160along the exclusion zone225under control of the secondary control system109″, as indicated by arrow A5.

Once the malfunctioning container handling vehicle240,X is within the service area160, the main control system109′ may be used to re-classify the exclusion zone225allowing the operative vehicles250to enter the previously existed exclusion zone225.

It shall be noted that in the example ofFIGS.5A-5Fit is shown a container handling vehicle250operating on an upper rail system108, i.e. the transport rail system108, however the operation will be identical for a delivery vehicle330,340,350operating on a lower rail system308, i.e. a delivery rail system308(as illustrated inFIGS.3A and3B).

FIGS.6A and6Bare perspective views of ride-on service vehicles suitable for operating on a rail system of an automated storage and retrieval system, whereFIG.6Ashows a service vehicle having two set of wheels configured to follow the rails in X and Y directions andFIG.6Bshows a service vehicle having caterpillar tracks configured to drive on top of the rail system. Another service vehicle20suitable for the operations described above is shown inFIG.7A,FIG.7BandFIG.7C.

InFIG.6Athe service vehicle20comprises a lifting mechanism. In both examples ofFIGS.6A and6Bthe service vehicles20comprises a seat25for the operator and a support base22for support of malfunctioning vehicles240,340and driving means23to enable movement of the service vehicle20. The service vehicle20could of course comprise other configurations and the present invention is not limited to these two examples.

InFIG.6Athe driving means23comprises two set of four wheels, where at least one of the sets may be raised and lowered. Hence, the driving means are similar to the driving means of the above described container handling vehicles250and container delivery vehicles350. The wheels follow the rails110,310,111,311of the transport and/or delivery rail system(s)108,308.

InFIG.6Bthe driving means23of the service vehicle20comprises caterpillar tracks configured to drive on top of the rails110,310,111,311, thereby allowing movement in any direction in the horizontal planes P,PLof either the transport rail system108or the delivery rail system308.

FIGS.7-9show a service vehicle20, in which all operations of the vehicle20are performed fully remotely, that is, without any need for a human operator to directly interact with a control system onboard the vehicle20during the service procedure.

The service vehicle20ofFIGS.7-9comprises two caterpillar tracks/rollers6,7coupled to two opposite vertical sides of a vehicle body3. At least one of the two other vertical sides of the vertical body3is configured to receive at least one malfunctioning vehicle240,340to be serviced.

FIGS.7-9shows a particular configuration where the service vehicle20comprises two guiding pins35attached to each of the opposite vertical sides of the vehicle body3onto which the caterpillar tracks6,7are connected. The ends of each guiding pins35nearest the container handling vehicle receiving side of the vehicle body3displays a tapered end allowing the malfunctioning vehicle240,340to be guided correctly into the vehicle body3. A remotely operated registration unit9in form of a forward camera9aand a rearward camera9bis mounted on the top horizontal side of the vehicle body3.

The transfer device8comprises a lifting mechanism8cwhich includes one or more vertical linear actuators8f. Each of the actuators8fhas one end connected to a pivot support8hthat pivotally couples to the vehicle body3with a rotational axis parallel to the underlying rail system108and the other end to a lifting claw8d. The lifting claws8dmay be displaceable in a horizontal direction relative to the vehicle body3by use of horizontal linear actuators8i, i.e. with a horizontal non-zero component.

The service vehicle20is remotely operated by a remote control system via one or more onboard transmitters36. Alternatively, or in addition, similar transmitters36may be arranged on the vehicle body3, within the registration unit9, on one or both of the rollers6,7, etc.

As for the above disclosed embodiments the caterpillar tracks/rollers6,7have a length L extending across a plurality of grid cells122, preferably four or more.

The opening of the vertical containing handling vehicle receiving side of the vehicle body3, including any guiding pins35, has a minimum width G being equal to, or larger than, the overall width of the malfunctioning vehicle(s)240,340to be serviced.

The procedure for picking up a malfunctioning vehicle240,340by the service vehicle20may proceed in the following way:(FIG.8A) The service vehicle20approaches, along an exclusion zone, a position adjacent to the one or more malfunctioning vehicles240,340to be transported using signal communication between the main control system109′ and the one or more of the onboard transmitters/receivers. If needed, the orientation of the service vehicle20is changed so that the vehicle receiving opening of the service vehicle20is facing towards the malfunctioning vehicle(s)240,340.(FIGS.8Band C) The service vehicle20is remotely guided so that the malfunctioning vehicle(s)240,340enters through the receiving opening of the vehicle body3, between the two caterpillar tracks/rollers6so that the transfer device8is in an interacting position, i.e. with the plurality of lifting claws8darranged on two opposite vertical sides of the or each malfunctioning vehicle240,340. Alternatively, the service vehicle20may be kept still, and the malfunctioning vehicle(s)240,340may be remotely guided into the vehicle receiving opening. The correct horizontal position of the malfunctioning vehicle240,340inside the vehicle body3can be further controlled by a stopper37arranged on the vertical side opposite of the receiving opening. Such a stopper37will also contribute to increase the structural stability of the malfunctioning vehicle240,340within the vehicle body3. In the example shown inFIGS.7-9this stopper is illustrated as a horizontal extending bar arranged to abut the malfunctioning vehicle240,340when the latter is fully inside the vehicle body3of the service vehicle20.(FIG.9A) When the transfer device8is in the interacting position relative to the malfunctioning vehicle(s)240,240, the lifting claws8dare displaced horizontally using the horizontal linear actuators8iuntil the lifting claws8dmake physical contact with the malfunctioning vehicle(s)240,340.(FIG.9B) The vertical linear actuator(s)8fis/are remotely operated, causing the vehicle body3to be lifted from the rail system108due to the pivoting movement of the pivot support(s)8h. As a result of the established physical contact between the lifting claws8dand the malfunctioning vehicle(s)240,340, the latter is lifted from the rail system108, thereby setting the service vehicle20in a transport position.The service vehicle20is moved to its predetermined position on the rail system108, or out of the rail system108, with the one or more malfunctioning vehicles240,340.

In all embodiments, the rollers6,7comprise endless tracks (i.e. looped chains)6ddriven by toothed belt wheels6a,6barranged within the chains6d. However, it may be envisaged configuration where one or more of the toothed wheels6a,6bare arranged outside the looped chain6d. Instead of toothed wheels6,7, the rollers6,7may comprise alternative drive mechanism such as wheels having other types of means for meshing or coupling to their respective chains6d. Further, the rollers6,7may be composed of components other than endless belts, for example a set of wheels wide enough to cover at least one grid cell122.

All the embodiments of the service vehicle20inFIGS.7-9may be easily configured to be maneuvered on the rail system without the need for an onboard operator50, for example by operations performed entirely by a remotely located human operator50or by a fully or partly automated control system or a combination thereof.

Embodiments may also be envisaged where the full operation of the service vehicle20is partly due to the operation of an onboard operator and partly due to a remotely located human operator or alternatively a combination between the operation of an onboard operator and a fully or partly automated control system.

It is now referred toFIGS.10-14. Here, it is shown a service vehicle20for performing support operations in the automated storage and retrieval system1.

The service vehicle20comprises a vehicle body3with a central cavity25(FIG.10). A drive system40is provided in the lower part of the service vehicle20. The drive system40is configured to drive the service vehicle20along the track system108of the automated storage and retrieval system1. The drive system40comprises a motor, typically an electric motor, and a power source, typically a rechargeable battery. The drive system40further comprises a first set of wheels42and a second set of wheels44, where the service vehicle20is moving in a first direction (for example X-direction) when the first set of wheels42are in contact with the track system108,308and where the service vehicle20is moving in a second direction (for example the Y-direction) when the second set of wheels44are in contact with the track system108. The drive system40also comprises an actuator for bringing the desired set of wheels in contact with the track system. The drive system40further comprises a control system for controlling the movement of the service vehicle20within the system1. It should be noted that the drive system40of the service vehicle20is considered to be known for a person skilled in the art.

The service vehicle20further comprises a connection system30provided on a first side3A of the vehicle body3. The connection system30is connectable to, and disconnectable from, a connection interface CI, for example a connection interface CI of an additional support unit (seeFIG.15). The connection system30will be described in further in detail below.

First, it should be noted that the embodiment of the service vehicle20shown in the drawings comprises one connection system30provided on a first side3A of the vehicle body3and an additional connection system30provided on a second side3B, opposite of the first side3A (seFIG.13). For many of the applications described herein, one such connection system30may be sufficient. It is also possible to provide the service vehicle20with a corresponding connection system30on a third side and/or fourth side.

Now, the connection system30will be described in detail with reference toFIG.13,14andFIGS.19A-19D.

InFIG.19A, it is shown that the exemplary connection system30comprises a connector member or pin31protruding through an aperture or slot24of the vehicle body3. In the present embodiment, the connector pin31has two sections, a first section having a head or pin head31aand a second elongated section or shank31bdefined with a longitudinal axis X31. The shank31bis cylindrical in the present embodiment.

In the present embodiment, the slot24is a vertical slot24, in which the connector pin31can be moved vertically by means of an actuator34. The actuator34is an electric linear actuator34.

On the outside of the vehicle body3, a first contact body32is provided. The first contact body32can be connected to the connector pin31or to the vehicle body3at a horizontal distance from the pin head31a. In the present embodiment, the first contact body32is connected to and around the connector pin31.

In addition to the first contact body32, the connection system30comprises a second contact body33provided at a vertical distance from the first contact body32.

A rigid member38is provided on the inside of the vehicle body21. The rigid member38is used to connect the actuator34to the connector pin31and also to the first contact body32. Moreover, the second contact body33is connected to the rigid member38by means of a connector39. Hence, when the actuator34is moving vertically, also the rigid member38, the connector pin31and the first and second contact bodies32,33are moving vertically.

InFIG.19A, the connection system30is in its lower or unlocked position.

It is now referred toFIGS.19B and19C, in which the connection interface CI is shown to comprise a plate-shaped connection structure CS with a keyhole KH. In the present embodiment, the keyhole KH comprises a circular opening Kha into which the pin head31acan be easily inserted and a narrower slot KHb above the circular opening Kha into which the shank31bcan be moved, but from which the pin head31acannot easily be retrieved. Hence, when the connection system30is in the lower or unlocked position (and the connection interface CI is stationary), the connector pin31may be moved into and out from the keyhole KH.

It is now referred toFIG.19D. Here it is shown that the connector pin31has been moved into the keyhole KH and then moved upwardly by means of the actuator34. This position is referred to as an upper or locked position. In this locked position, if the service vehicle is moved to the left inFIG.19D, the connection structure CS will be pulled together with the service vehicle20as the pin head31is engaged with the rear side RS of the connection structure CS. By moving the connector pin downwardly to the unlocked position by means of the actuator, the connection system30will be free to move out of engagement with the connection interface CI.

It should be noted that inFIG.19D, contact surfaces32a,33aof the first and second contact bodies32,33are in contact with a front side FS of the connection structure CS. Hence, the first and second contact bodies32,33provide that the connection interface CI is oriented as desired with respect to the vehicle body3. Preferably, the connection interface CI is oriented parallel with the side3A of the vehicle body3. Preferably, both the first side3A of the vehicle body21and the connection interface CI are oriented vertically as shown inFIGS.19A-D.

InFIG.19Dit is also shown that the longitudinal distance Lcs between the contact surface32aof the contact body32and the pin head31ais equal to or a little longer than the thickness Tcs of the connection structure CS.

It is now referred toFIGS.13and14. Here it is shown that the connection system30comprises two connector pins31on the first side3aof the vehicle body3. The two connector pins31are provided in two slots24in the vehicle body3, where the two slots24are spaced apart from each other.

The further connection system30on the second side3bof the vehicle body21also comprises two such connector pins31provided in two spaced apart slots24.

The rigid member38described above with reference toFIGS.12-14is here used as a rigid cross member38which is connecting the connector pins31to each other. In this way, the two connector pins31are moved vertically in parallel. It should be noted that two actuators34are connected between the inside of the vehicle body3and each cross member38.

The service vehicle20is based on the type of prior art container handling vehicle250shown inFIG.1C, i.e. a container handling vehicle250with a cavity arranged centrally within the vehicle body252. InFIG.14, another example of such a container handling vehicle250is shown.

Only minor modifications are needed to manufacture a service vehicle20from such a container handling vehicle250. One modification is that slots must be provided in the vehicle body3and that the different parts of the connection system30must be mounted to the vehicle. Preferably, the container lifting device of the prior art container handling vehicle250is removed to save costs and also to provide sufficient space for the actuators34. In some applications, it may be required to modify the drive system, as the service vehicle20may be designed to handle a larger total weight than a typical container handling vehicle. Hence, a more powerful motor of the drive system40may be needed, possibly also more robust bearings for the wheels may be used etc. All in all, the number of modifications are still relatively low. In addition, relatively small modifications in the control system are needed, for controlling the actuators34.

The automated storage and retrieval system1may comprise one or more service vehicles20and at least one additional support unit. The additional supporting unit comprises a connection interface CI to which the service vehicle20can connect to and disconnect from. Together, the service vehicle20and the additional supporting units form a support system for an automated storage and retrieval system1.

In general, the connection system30may be configured to be connected to the connection interface CI of the additional support unit by the following operation:moving the connector pin31to a first (here: lower) position aligned with the keyhole KH of the connection interface CI of the unit;moving the connector pin31horizontally into the keyhole KH by moving the service vehicle20along the track system towards the unit;moving the connector pin31to a second (here: upper) position different from the first position.

In this second position, movement of the service vehicle20away from the unit will cause the unit to be pulled by the service vehicle. Movement of the service vehicle20towards the unit will cause the unit to be pushed by the service vehicle. In the two directions mentioned here, the service vehicle20and the unit will move along tracks110ofFIG.15.

Movement of the service vehicle in a direction perpendicular to the push/pull direction will cause the unit to be dragged or pushed in parallel with the service vehicle20. This last movement will, as described in the introduction above, require that the correct set of wheels become in contact with tracks111, or tracks parallel with tracks111, inFIG.15.

In general, the connection system30is configured to be connected from the connection interface CI by the following operation:lowering the connector pin31to its first (here: lower) position again;moving the connector pin31horizontally out of the keyhole KH by moving the service vehicle20along the rails track system108away from the unit.

Examples of different support units will be described through the following examples:

It is here referred toFIGS.15,16and17. Here, the service vehicle20is connected to an intermediate supporting unit60. The purpose of the intermediate supporting unit60is to transport a failed container handling vehicle240which is stuck in a position on the rail system108and is not itself capable to move to the service area due to a failure, such as an empty battery, an electrical or mechanical failure etc. To fix the vehicle240, it must be moved to the service area.

As shown inFIG.15, the intermediate supporting unit60comprises a connection interface CI fixed to a rigid framework formed by elongated bar elements62protruding away from the connection interface CI and cross bar elements61interconnecting the bar elements62. In addition, the framework of the unit60comprises downwardly protruding supporting elements64.

The connector pins31of the connection system30of the service vehicle20are connected to the connection interface CI and the connector pins31are in their upper and locked position. It can also be seen inFIG.15that the unit60is lifted by the service vehicle20, i.e. the unit60is not in contact with the track system108.

The distance between the respective downwardly protruding supporting elements64are adapted to the track system108. Hence, by lowering the connector pins31of the service vehicle20, the downwardly protruding supporting elements64will come into contact with the track system108and the service vehicle20can disconnect from the unit60. The service vehicle20can re-connect to the unit60by moving towards the unit60with its connector pins31in their lower position and then elevate the connector pins31when they have been inserted into the keyhole of the connection interface again.

InFIG.15, it is shown that the additional support unit60comprises a further connection system70for connection to a container handling vehicle240,250. The connection system70comprises a wheel actuator72and a push body74,75for contact with the container handling vehicle240,250when it is pushed by the service vehicle20. In addition, the further connection system70comprises a pull body76for contact with the container handling vehicle240,250when pulled by the service vehicle20. The pull body76may be hook or other type of connection interface for connection to an interface of the container handling vehicle240,250.

It should be noted that the connection system30of the service vehicle20in this example may have a third position. In the first position, as described above, the connection system30has lowered the unit and the unit is in contact with the track system108. Here, the service vehicle may move the connector pin31into or out from the keyhole KH of the connection interface CI. In the second position, the connection system30has lifted the unit and the unit is no longer in contact with the track system108. However, the pull body76is not sufficiently elevated to be moved over the vehicle240,250. Hence, to engage the additional connection system70with the vehicle240,250, the connector pins31and hence the unit60is elevated to a third position above the second position. Now, the pull body76of the unit can be moved over the vehicle240,250and then the connection system30can be lowered to the second position again. Now, the pull body76is engaged with the vehicle240,250. To disconnect from the vehicle240,250, the unit60is elevated from the third position and moved away from the vehicle240,250, as the pull body76is not engaged with the vehicle240,250in the third position.

The wheel actuator72is connected to a mechanical interface72aof the container handling vehicle240,250for adjusting wheel elevation of the container handling vehicle240,250, i.e. to mechanically control if the wheels should be in contact with tracks110or tracks111of the track system. The wheel actuator72is driven by an electric motor controlled by the control system of the service vehicle20or by a control system of the entire system1.

It should be noted that the length of the elongated bar elements62is adapted to the length between the rails111. Hence, when moving along tracks111, four tracks11are in contact with the wheels of the service vehicle20and the wheels of the vehicle301, while when moving along tracks110, the same two tracks are used both by the service vehicle20and the vehicle240,250.

It should be noted that in this example, no modification of the vehicle340,350is needed.

It is now referred toFIGS.18A-D. The additional support unit is here a counterweight unit60dfor balancing the service vehicle20. The unit60dhas a connection interface CI (not shown) which inFIGS.18A and18Bis connected to the connection system30provided on the second side3B of the vehicle body3. The counterweight unit60dis lifted by the service vehicle20.

The purpose of the counterweight unit60dis to enable the service vehicle20to lift and transport a failed container handling vehicle240,250of the type shown inFIGS.18A and18B. The container handling vehicle240,250is similar to prior art vehicles, with one modification: The container handling vehicle240,250comprises a connection interface CI. In this example, the connection interface CI is provided as two openings in the vehicle body252, one opening for each of the connector pins31of the connection system30on the second side3B of the vehicle body3of the service vehicle20.

InFIG.18C, it is shown that the connector pins31of the connection system30moved into the openings of the connection interface CI of the vehicle240,250.

InFIG.18D, it is shown that the connection system30is in the second (or third) position, lifting the vehicle240,250up from the grid. Due to the counterweight unit60d, the service vehicle20will not tilt when lifting the vehicle240,250.

Alternative Embodiments

In the above embodiments, the connector pin31including the pin head31awas rotationally symmetrical around its longitudinal axis.

It is now referred toFIG.20A-D, where some examples of alternative embodiments are shown.

InFIG.20A, the connector pin31is not rotationally symmetrical, as only the upper part of the pin head31ais protruding upwardly in a direction perpendicular to the longitudinal axis X31. Here, the keyhole KH of the connection interface is oval-shaped.

InFIG.20B, the pin head31ais a rectangle protruding up from the connector pin31. Here, the keyhole KH of the connection interface is circular.

InFIG.20C, the pin head31acorresponds to the one shown inFIG.20B. However, here the distal end of the head is rounded, to ease insertion into the keyhole KH. Here, the keyhole KH of the connection interface is semicircular.

InFIG.20D, the pin head31ais formed by providing a notch in the connector pin31itself, thereby separating the connector pin31into two separate sections, a distal section forming the pin head31aand a proximal section31b. Here, the keyhole KH of the connection interface is rectangular.

It should be noted that all of the above connector pins31may be used in combination with all of the above keyholes KH. It should be noted that the present invention is not limited to the specific examples described and shown in the drawings, many other alternatives are considered to be within the scope of the invention as defined by the claims.

It should also be noted that the operation of the actuator34may be dependent on, or independent of, the operation of the drive system40. In one embodiment, the vertical distance between the slot24and the track system will be the same when the service vehicle is moving along tracks110and when the service vehicle is moving along tracks110. In such a case, the operation of the actuator34can be independent from the drive system40. However, in case the vertical distance between the slot24and the track system is different when the service vehicle is moving along tracks110and when the service vehicle is moving along tracks111(due to different elevation of the vehicle body3and the different sets of wheels), then the actuator may be operated to change the height of the connector pins based on the travel direction.

In the preceding description, various aspects of the method and its related system according to the invention have been described with reference to the illustrative embodiment. For purposes of explanation, specific numbers, systems and configurations were set forth in order to provide a thorough understanding of the system and its workings. However, this description is not intended to be construed in a limiting sense. Various modifications and variations of the illustrative embodiment, as well as other embodiments of the method and the system, which are apparent to persons skilled in the art to which the disclosed subject matter pertains, are deemed to lie within the scope of the present invention.

1Automated storage and retrieval system3Service vehicle body3AFirst side of service vehicle body3BSecond side of service vehicle body6First propulsion means/propulsion mechanism/rolling means/roller/caterpillar track6aFirst toothed belt wheel for each endless belt 6, 76bSecond toothed belt wheel for each endless belt 6, 76dEndless tracks/Looped chain/endless belt7Second propulsion means/propulsion mechanism/rolling means/roller/caterpillar track8Transfer device8cTransfer motor/lifting mechanism8dAttachment device/lifting hook/lifting claw8fVertical linear actuator8hPivot support for vertical linear actuator8iHorizontal linear actuator9Registration unit/image capturing unit9aForward camera9bRearward camera20Service vehicle22A support base for malfunctioning vehicle23Driving means service vehicle24Aperture/slot25Central cavity30Connection system31Connector member/connector pin31aFirst section/pin headX31Longitudinal axis31bSecond elongated section or shank32First contact body33Second contact body34Actuator35Guiding pin36Transmitter37Stopper38Rigid member39connector40Drive system service vehicle/motor/power source42First set of wheels service vehicle44Second set of wheels service vehicle60Intermediate support unit/additional support unit60dCounterweight unit61Elongated bar element62Cross bar element64supporting elements70connection system of additional support unit72Wheel actuator72aMechanical interface74, 75Push body76Pull body108Rail system108aFirst transport rail system108bSecond transport rail system108cThird transport rail system109′Main Control system/first communication system109″Secondary control system/second communication system110First set of parallel rails in first direction (X)111Second set of parallel rails in second direction (Y)115Grid opening in transport rail system119Delivery column/transfer column120Delivery column/transfer column122Grid cell of transport rail system125Vehicle blocking barrier130aFirst vehicle passage between transport rail systems130bSecond vehicle passage between transport rail systems160Service area to transport rail system for service vehicle160aFirst service area160bSecond service area160cThird service area225Exclusion zone on transport rail system230Parked container handling vehicle230′Boundary defining, parked vehicle230″Non-boundary defining, parked vehicle240Malfunctioning container handling vehicle250Operative container handling vehicle251Wheel assembly for container handling vehicle252Vehicle body for container handling vehicle300Delivery framework structure308Delivery rail system310First set of parallel rails in first direction (X) on delivery railsystem311Second set of parallel rails in second direction (Y) on deliveryrail system315Grid opening in delivery rail system322Grid cell of delivery rail system330Parked container delivery vehicle330′Boundary defining, parked vehicle330″Non-boundary defining, parked vehicle340Malfunctioning container delivery vehicle350Operative container delivery vehicle351Wheel assembly for container delivery vehicle352Storage container supportXFirst directionYSecond directionZThird directionPHorizontal plane of rail systemA1, A2Arrow indicating movement of container handling vehicleA3, A4Arrow indicating movement of service vehicleA5Arrow indicating movement of service vehicle withmalfunctioning container handling vehicleCIConnection interfaceCSConnection structureGMinimum widthKHKeyholeKhaCircular openingKHbslotRSRear sideFSFront sideLcsLongitudinal distanceTcsThickness connection structure