Patent Description:
<FIG> discloses a typical prior art automated storage and retrieval system <NUM> with a framework structure <NUM> and <FIG> and <FIG> discloses two different prior art container handling vehicles <NUM>,<NUM> suitable for operating on such a system <NUM>.

In <FIG> and <FIG> two wheels in each set are fully visible. At least one of set wheels 201b,301b,201c,301c can be lifted and lowered, so that the first set of wheels 201b,301b and/or the second set of wheels 201c,301c can be engaged with the respective set of rails <NUM>, <NUM> at any one time.

Each prior art container handling vehicle <NUM>,<NUM> also comprises a lifting device (not shown) for vertical transportation of storage containers <NUM>, e.g. raising a storage container <NUM> from, and lowering a storage container <NUM> into, a storage column <NUM>. The lifting device comprises one or more gripping / engaging devices which are adapted to engage a storage container <NUM>, and which gripping / engaging devices can be lowered from the vehicle <NUM>,<NUM> so that the position of the gripping / engaging devices with respect to the vehicle <NUM>,<NUM> can be adjusted in a third direction Z which is orthogonal the first direction X and the second direction Y. Parts of the gripping device of the container handling vehicle <NUM> is shown in in <FIG> and is indicated with reference number <NUM>. The gripping device of the container handling device <NUM> is located within the vehicle body 301a in <FIG>.

The storage volume of the framework structure <NUM> has often been referred to as a grid <NUM>, where the possible storage positions within this grid is referred to as a storage cell. Each storage column may be identified by a position in an X- and Y-direction, while each storage cell may be identified by a container number in the X-, Y and Z-direction.

The central cavity container handling vehicles <NUM> shown in <FIG> may have a footprint that covers an area with dimensions in the X and Y directions which is generally equal to the lateral extent of a storage column <NUM>, e.g. as is described in <CIT>. The term 'lateral' used herein may mean 'horizontal'.

The rail system <NUM> typically comprises rails with grooves into which the wheels of the vehicles are inserted.

The access station may typically be a picking or a stocking station where product items are removed from or positioned into the storage containers <NUM>. In a picking or a stocking station, the storage containers <NUM> are normally not removed from the automated storage and retrieval system <NUM>, but are returned into the framework structure <NUM> again once accessed. A port can also be used for transferring storage containers to another storage facility (e.g. to another framework structure or to another automated storage and retrieval system), to a transport vehicle (e.g. a train or a lorry), or to a production facility.

When a storage container <NUM> is to be stored in one of the columns <NUM>, one of the container handling vehicles <NUM>,<NUM> is instructed to pick up the storage container <NUM> from the pick-up port column <NUM> and transport it to a location above the storage column <NUM> where it is to be stored. After any storage containers positioned at or above the target position within the storage column stack <NUM> have been removed, the container handling vehicle <NUM>,<NUM> positions the storage container <NUM> at the desired position. The removed storage containers may then be lowered back into the storage column <NUM>, or relocated to other storage columns.

From prior art <CIT> it is known a robotic service device for use on a robotic picking system grid. The robotic service device is capable of driving to any location on the grid in order to perform maintenance operations or cleaning. Additionally, the service device may be used to rescue robotic load handling devices operational in the picking system. The robotic service device may comprise a releasable docking mechanism to enable it to dock and latch on to malfunctioning load handling devices. The service device may also be provided with cleaning means and camera means to enable the condition of the grid and other robotic devices to be monitored.

It may be a problem with the prior art robotic service vehicles that the required lifting capacity of the single robotic service vehicle lifting a malfunctioning vehicle off the rail system is too high such that the robotic service vehicle is either not able to lift the malfunctioning vehicle and/or, if the robotic service vehicle is able to lift the malfunctioning vehicle off the rail system, it is unstable during transport requiring large counterweight(s) and or slow transportation speed/acceleration.

The required lifting capacity may be even higher if the malfunction vehicle carries a heavy storage container. This may incur an even larger problem. It is an objective of the invention to solve the challenges of retrieving vehicles from a rail system.

The invention provides for the possibility of rescuing container handling vehicles while the automated storage and retrieval system is in operation, i.e. while the remaining container handling vehicles are in operation on the rail system. The invention eliminates the need for a manned service vehicle improving HSE for the system. However, in the event of a major collision where vehicles are off track, it may be required that an operator enters the rail system.

It is described a rescue system for retrieving a malfunctioning vehicle from a rail system of an automated storage and retrieval system, the rail system comprising a plurality of rails with tracks extending in an X-direction and a plurality of rails with tracks extending in a Y-direction perpendicular to the X-direction, a plurality of remotely operated vehicles configured to move in the X and Y-directions on the tracks of the rail system,.

The lifting device may comprise a vertical plate with a lip extending therefrom. Alternatively, other types of lifting devices may be used as long as they provide the required function of a horizontal part engageable with a malfunctioning vehicle such that the malfunctioning vehicle can be lifted off the rail system by vertical movement of the horizontal part relative the rail system. The lifting device may further comprise any necessary components required to lift and lower the lifting device relative the rail system, such as motor, any necessary guide or actuator for guiding the lifting device substantially vertical, connection to a power source for driving the motor etc. The motor, and possibly also the power source, may be designed with less lifting capacity than the prior art service vehicles which utilizes only one motor to lift a container handling vehicle off the grid.

The container handling vehicle can be in the form of prior art container handling vehicles as the ones exemplified in <FIG> configured for receiving storage containers from below, or in the form of a container delivery vehicle configured for receiving storage containers from above.

It is further described a rescue system for retrieving a malfunctioning vehicle from a rail system of an automated storage and retrieval system, the rail system comprising a plurality of rails with tracks extending in an X-direction and a plurality of rails with tracks extending in a Y-direction perpendicular to the X-direction, the rails defining a plurality of grid cells, wherein a plurality of remotely operated vehicles are configured to move in the X and Y-directions on the tracks of the rail system,.

The vehicle rescue modules may comprise a lifting plate with a lip extending at a height above an upper surface of the wheel base unit. The height may be within <NUM> or it may be less or it may be more.

The plurality of remotely operated vehicles may comprise wheel base units providing mobile platforms, each corresponding in area to a single grid cell of the rail system, for storage container lifting modules mounted thereon.

A grid cell may be defined as the area, including the track width, delimited by a pair of tracks in X and Y direction around an access opening of the rail system.

The first and second rescue vehicles may comprise communication means for synchronous operation. This may further increase the chances of a successful lifting operation by preventing jamming which may occur during un-even lifting.

The communication means may enable communication between the first and second rescue vehicles. Such communication may be internal or direct communication between the rescue vehicles. The means of internal or direct communication can be IR, wireless (WiFi), light (LiFi), Bluetooth, NFC or similar.

The system may further comprise a control system, and the control system may comprise cooperative communication means configured to communicate with the communication means of the first and second rescue vehicles to operate synchronously.

The first or second rescue vehicle may be a master rescue vehicle and the other of said first or second rescue vehicle may be a slave rescue vehicle which is at least partly operated by instructions from the master rescue vehicle. The master/slave operation may be limited to the lifting operation, while normal operation of the rescue vehicle(s) in terms of horizontal movement on the rail system may be under control of the control system operating the container handling vehicles. When entering the rail system, the rescue vehicles may be added to the control system operating the remotely operated vehicles such that they are operated as a standard container handling vehicle reducing the probability of collision with the container handling vehicles. Once two rescue vehicles have lifted a malfunctioning container handling vehicle, the control system know how many cell spaces the two rescue vehicles and the malfunctioning container handling vehicle requires, and will take this into consideration when determining what path to use for transporting the malfunctioning vehicle to e.g. a service area.

The rail system may be at a top level of a storage and retrieval system.

The rail system may be a delivery rail system.

The rescue vehicles may comprise two set of wheels for movement in the X and Y directions along the rail system.

The lifting device may comprise an actuator configured to raise and lower the malfunctioning vehicle relative the rail system.

The lifting device may be configured to only move up and down in the Z-direction (i.e. be raised and lowered). This may be achieved using a lifting device in the form of a linear actuator or similar.

However, alternatively, the lifting device may be configured to, in addition to be moved up and down in the Z-direction, also be configured for lateral movement in the X-direction and/or the Y-direction. The latter being advantageous in operations where a larger contact area between the lifting device and the malfunctioning container handling vehicle is required.

At least one of the first and/or second rescue vehicles may comprise at least one rotary drive to winch up a lifting frame and or a track shift motor of the malfunctioning container handling vehicle. This render possible manual/mechanical oversteering of any stuck lifting device or gripper and or set of wheels of the container handling vehicle.

If a container handling vehicle malfunctions with the lifting device/grippers in a lower position, the rescue vehicle may comprise rotary drive for connection to the malfunction vehicle and raise the lifting device/grippers before the malfunctioning vehicle is transported off the rail system.

The rotary drive may be a pipe motor which is used to override the lifting frame/grippers motor and/or track shift motor. One or more cameras arranged on the same or another rescue vehicle may be arranged to monitor the process and provide useful information in terms of aligning the rotary drive relative the complementary socket on the malfunctioning vehicle. In one aspect, the camera may be, or form part of, the communication means between the first and second rescue vehicles.

The at least one rotary drive may be pivotable, and an axis of the rotary drive may be configured to be pivoted between a stowed vertical position during movement of the first or second rescue vehicle on the rail system, and may further be configured to be pivoted to a deployed horizontal position for winching up the lifting frame and or the track shift motor of a malfunctioning container handling vehicle.

In particular, the rotary drive may be pivoted between its stowed position to the deployed horizontal position as the rescue vehicle is moved towards the malfunctioning vehicle so that the drive shaft can protrude to engage the socket in the malfunctioning vehicle as it approaches.

The rotary drive for the lifting frame may be arranged in an upper part of the rescue vehicle and, when the rotary drive is in the deployed horizontal position, the rotary drive can be supported by an actuator.

Alternatively, the rotary drive can be connected to a linear actuator for movement between the stowed position and the deployed position. When in the stowed position, the perimeter of the rotary drive may be arranged within a horizontal perimeter of the wheel base unit, and when in the deployed position, at least a portion of the rotary drive may extend beyond the perimeter of the wheel base unit. In other words, when in the stowed position, the rescue vehicle may have a footprint equal to or less than a grid cell of the rail system and in the deployed position, the rotary drive may extend into a neighboring grid cell upon actuation of the linear actuator. This provides for the possibility that the service vehicle does not occupy more than one cell when moving on the rail system.

It is further described a rescue vehicle for retrieving a malfunctioning vehicle from a rail system of an automated storage and retrieval system, the rail system comprising a plurality of rails with tracks extending in an X-direction and a plurality of rails with tracks extending in a Y-direction perpendicular to the X-direction, a plurality of remotely operated vehicles configured to move in the X and Y-directions on the tracks of the rail system, wherein the rescue vehicle comprises a wheel base unit configured to run on tracks of the rail system, the wheel base unit providing a mobile platform corresponding in area to a single grid cell for a vehicle rescue module mounted thereon, the vehicle rescue module being orientated in a first direction of the rail system; wherein the vehicle rescue module comprises a lip on at least one of the sides of the module arranged at a level above the level of the wheel base unit, and wherein the lip extends into a neighboring cell when the rescue vehicle is positioned in centre of a grid cell.

The rescue vehicle may further comprise a rotary drive to winch up a lifting frame and or a track shift motor of a malfunctioning container handling vehicle. It is further described an automated storage and retrieval system, comprising:.

It is further described a method of retrieving a malfunctioning container handling vehicle from a rail system with perpendicular tracks in X and Y direction and wherein a plurality of remotely operated vehicles are arranged on the rail system, and wherein each of the vehicles comprises a vehicle body and side portions, and wherein at least two opposite side portions on each vehicle comprises a recess, wherein the method comprises:.

The malfunctioning container handling vehicle may comprise a lifting device for lifting and lowering storage containers from below, or the malfunctioning container handling vehicle may be a delivery vehicle configured to receive storage containers from above.

The method may further comprise, prior to the step of engaging the lifting devices on opposite sides of the malfunctioning vehicle, a step of operating a rotary drive to winch up a lifting frame and or a track shift motor of a malfunctioning container handling vehicle.

It is further described a rescue system for retrieving a malfunctioning vehicle from a rail system with perpendicular tracks in X and Y direction and wherein a plurality of remotely operated vehicles are configured to move laterally on the rail system, wherein the rescue system comprises:.

In all of the disclosed examples, utilizing two rescue vehicles operating in common will require smaller lifting motors than when lifting a container handling vehicle using only one rescue vehicle where one single motor needs to be capable of lifting off the malfunctioning vehicle off the rail system. Furthermore, the solution provides for more stable transport of malfunctioning vehicle when compared to when using a single rescue vehicle, because the solution gives an advantageous center of gravity.

Another advantage of the solution is a larger flexibility in accessing areas on the rail system compared to when using smaller rescue vehicles.

In order for the lifting device to support malfunctioning container handling vehicles without moving the lifting device horizontally relative the rescue vehicle during lifting operations, a part of the lifting device such as a lip or similar, extends into a neighboring cell when the rescue vehicle is positioned in center of a cell. In order for the rescue vehicles to pass by container handling vehicles in neighboring cells, thereby occupying as little space on the rail system as possible, the container handling vehicles preferably have recesses on two or all sides where a neighboring rescue vehicle can pass, while delivery vehicles and so-called single cell robots may have recesses on all sides. The recesses may extend along the whole length of each side of the container handling vehicles. In addition, the recess may have a sufficient extension in the Z direction to take into account different height of the container handling vehicle dependent on which of the set of wheels that are in contact with the rail system.

These can be run on a separate control system, but it would have been simplest and run on the same system as the rest of the vehicles.

It is important to note that the (single-cell) drones can be lifted from both the short side (Y) and the long side (X).

In order to be able to engage with the malfunctioning container handling vehicle, the container handling vehicles may have at least one recess which is complementary shaped relative the lifting plate of the rescue vehicle to be lifted. However, as an alternative, the container handling vehicle may be lifted off the rail system by being sandwiched between two rescue vehicles from opposite sides and then lifted off the rail system, or by using magnets or similar. For example, the rescue vehicles may be fitted with a vertically moveable surface, e.g., a conveyor device or similar - the two rescue vehicles could then push together to hold the malfunctioning vehicle sandwiched between them.

The recess may be at the interface where a carrier module for a container support on a delivery vehicle or a container lifting module is mounted on to a wheel base unit.

Identical rescue vehicles may be used regardless of operating on a top level of a storage and retrieval system or on a delivery rail system, or on a single/single, single/double or double/double track. This provides for large flexibility as the rescue vehicle is the same either in retrieving container handling vehicles with lifting device/grippers or delivery vehicles. For example, using identical rescue vehicles, with opposite orientation, such as one lifting device east-facing and one lifting device west-facing, will provide for the possibility of retrieving both north-facing and south-facing malfunctioning vehicles.

The rescue vehicle may further be provided with visual inspection means such as to perform visual inspection on the rail system or control or check vehicles that have problems on the rail system. The visual inspection means may comprise one or more cameras.

A different automated storage and retrieval system <NUM> is shown in part in <FIG>. The upright members <NUM> constitute part of a framework structure <NUM> onto which a transport rail system <NUM> with a plurality of container handling vehicles <NUM>,<NUM> are operating.

Below this transport rail system <NUM>, near the floor level, another framework structure <NUM> is shown which partly extends below some of the storage columns <NUM> of the framework structure <NUM>. As for the other framework structure <NUM>, a plurality of vehicles <NUM> may operate on a rail system <NUM> comprising a first set of parallel rails <NUM> directed in a first direction X and a second set of parallel rails <NUM> directed in a second direction Y perpendicular to the first direction X, thereby forming a grid pattern in the horizontal plane PL comprising a plurality of rectangular and uniform grid locations or grid cells <NUM>. Each grid cell of this lower rail system <NUM> comprises a grid opening <NUM> being delimited by a pair of neighboring rails 310a,310b of the first set of rails <NUM> and a pair of neighboring rails 311a,311b of the second set of rails <NUM>.

The part of the lower rail system <NUM> that extends below the storage columns <NUM> are aligned such that its grid cells <NUM> are in the horizontal plane PL coincident with the grid cells <NUM> of the upper rail system <NUM> in the horizontal plane P.

Hence, with this particular alignment of the two rail systems <NUM>,<NUM>, a storage container <NUM> being lowered down into a storage column <NUM> by a container handling vehicle <NUM> can be received by a delivery vehicle <NUM> configured to run on the rail system <NUM> and to receive storage containers <NUM> down from the storage column <NUM>. In other words, the delivery vehicle <NUM> is configured to receive storage containers <NUM> from above, preferably directly from the container handling vehicle <NUM>,<NUM>.

<FIG> shows an example of such a delivery vehicle <NUM> comprising a wheel assembly <NUM> similar to the wheel assembly <NUM> described for the prior art container handling vehicle <NUM> and a storage container support <NUM> for receiving and supporting a storage container <NUM> delivered by an above container handling vehicle <NUM>,<NUM>.

After having received a storage container <NUM>, the delivery vehicle <NUM> may drive to an access station adjacent to the rail system <NUM> (not shown) for delivery of the storage container <NUM> for further handling and shipping.

<FIG> are perspective views of a rescue vehicle <NUM> seen from different sides. The rescue vehicle <NUM> comprises a wheel base <NUM> and a rescue module <NUM> mounted thereon. The lifting device <NUM> is disclosed with a vertical plate <NUM> with a lip <NUM> extending therefrom. In the disclosed example, the lifting device <NUM> is on a short side of the rescue vehicle <NUM> and the lip <NUM> extends along the whole side and further around a corner of the rescue vehicle <NUM> and at least partly along an adjacent long side. The part of the lip <NUM> on the long side of the rescue vehicle may extend shorter and or along the whole length of long side. In one example, there may be a continuous lip <NUM> around the whole rescue vehicle <NUM>, i.e. there may be a lip <NUM> on all sides of the rescue vehicle <NUM>.

The rescue vehicle <NUM> is disclosed with visual inspection means <NUM> such as to perform visual inspection on the rail system <NUM>,<NUM> or control or check vehicles that have problems on the rail system <NUM>, <NUM>, and or to monitor or assist in rescuing operations. The visual inspection means <NUM> may comprise one or more cameras.

The rescue vehicle is disclosed with two pivotable actuators <NUM>',<NUM>" for moving two rotary drives <NUM>',<NUM>", respectively. The rotary drive denoted <NUM>' is for manipulating the track shift motor of a malfunctioning container handling vehicle, whereas the rotary drive denoted <NUM>" is for manipulating a lifting frame/gripper motor of a malfunctioning container handling vehicle to rotate the lifting frame motor and any carried storage container <NUM> up and above the top of the rail system <NUM>,<NUM> such that the malfunctioning vehicle can be transported across the rail system <NUM>,<NUM>. In all <FIG>, the rotary drives <NUM>',<NUM>" are in the stowed vertical position. Furthermore, as disclosed in all <FIG>, the footprint of the rescue vehicle <NUM> is equal to or less than a grid of the underlying rail system <NUM>,<NUM>.

<FIG> show an example of a rescue vehicle <NUM> comprising a wheel base unit <NUM> and a vehicle rescue module <NUM> mounted thereon. Instead of the pivotable actuator of the rescue vehicle <NUM> in <FIG>, the rescue vehicle <NUM> comprises a linear actuator <NUM> for moving the rotary drive <NUM>'". The linear actuator <NUM> is arranged for moving the rotary drive <NUM>‴ between the stowed position (<FIG>) and the deployed position (<FIG>). As shown in <FIG>, when in the stowed position, the perimeter of the rotary drive <NUM>‴ is arranged within a horizontal perimeter of the wheel base unit <NUM> of the rescue vehicle <NUM>, and when in the deployed position, at least a portion of the rotary drive <NUM>‴ may extend beyond the perimeter of the wheel base unit <NUM>. The other components of the rescue vehicle <NUM> may be similar to the ones described in relation to <FIG>.

<FIG> show step-by-step two rescue vehicles of <FIG> when they are rescuing a container handling vehicle <NUM> with a cantilever construction (i.e. a prior art container handling vehicle <NUM> as shown in <FIG>). In <FIG>, the container handling vehicle <NUM> has malfunctioned with the lifting frame carrying a storage container <NUM> in an upper position (i.e. a lowermost part of the storage container <NUM> is above the underlying rail system <NUM>,<NUM> such that the container handling vehicle can be transported on the rail system <NUM>, <NUM>). The first rescue vehicle <NUM> comprises a lifting device <NUM> and is facing for engagement in a first direction, whereas the second rescue vehicle <NUM> comprises a lifting device on an opposite side of the vehicle relative the first rescue vehicle <NUM>, the lifting device <NUM> facing for engagement in a second direction opposite to the first direction. In <FIG> both of the rescue vehicles <NUM> are positioned in a distance away from the malfunctioning container handling vehicle <NUM>.

In <FIG>, one of the rescue vehicles <NUM> has positioned itself in a neighboring cell to the malfunctioning container handling vehicle <NUM>, on one of the opposite sides of the container handling vehicle <NUM> which comprise a recess <NUM> for engagement with the lifting device <NUM> of the rescue vehicle <NUM>. In the disclosed example, the lifting device <NUM> comprises a vertical plate <NUM> with a lip <NUM> for engagement with the recess <NUM>.

In <FIG>, the second rescue vehicle <NUM> has positioned itself on the opposite side of the malfunctioning container handling vehicle <NUM> and the lip <NUM> of the lifting device <NUM> has engaged with the recess <NUM>. As is further seen in <FIG>, the first and second rescue vehicles <NUM> have lifted the malfunctioning container handling vehicle <NUM> off the rail system <NUM>,<NUM> by operating the lifting devices <NUM> simultaneously (i.e. in tandem). The malfunctioning container handling vehicle <NUM> may be transported off the rail system <NUM>,<NUM> to a dedicated area, such that a service area or similar. <FIG> is an opposite view of <FIG>.

<FIG> show step-by-step two rescue vehicles of <FIG> when they are rescuing a malfunctioning container handling vehicle in the form of a delivery vehicle <NUM> (see e.g. <FIG>). Similar rescue vehicles <NUM> as the ones disclosed in <FIG> are used when rescuing the delivery vehicle <NUM>. The delivery vehicle <NUM> comprises a recess <NUM> around the whole circumference of the delivery vehicle <NUM> for engagement with the lifting device <NUM> of the rescue vehicle <NUM>. The recess <NUM> may be arranged between a wheel base unit <NUM> of the delivery vehicle <NUM> and a container supporting unit <NUM> of the delivery vehicle <NUM>.

Referring to <FIG>, one of the rescue vehicles <NUM> has positioned itself in a neighboring cell to the malfunctioning container handling vehicle <NUM>, on one of the opposite sides of the malfunctioning delivery vehicle <NUM>. The other rescue vehicle <NUM> is arranged in a distance from the malfunctioning delivery vehicle <NUM>. Referring to <FIG>, the other of the rescue vehicles <NUM> has positioned itself on an opposite side of the malfunctioning delivery vehicle <NUM>. <FIG> is an opposite view of <FIG>.

Referring to <FIG>, the first and second rescue vehicles <NUM> have lifted the malfunctioning delivery vehicle off the rail system <NUM>,<NUM> by operating the lifting devices <NUM> simultaneously (i.e. in tandem). The malfunctioning delivery vehicle <NUM> may be transported off the rail system <NUM>,<NUM> to a dedicated area, such that a service area or similar. <FIG> is a perspective side view of <FIG>.

An exemplary combined wheel base unit for the rescue vehicles <NUM> and the delivery vehicles <NUM> is shown in <FIG>. The wheel base unit <NUM> features a wheel arrangement 32a,32b having a first set of wheels 32a for movement in a first direction upon a rail system (i.e. any of the top rail system <NUM> and the delivery rail system <NUM>) and a second set of wheels 32b for movement in a second direction perpendicular to the first direction. Each set of wheels comprises two pairs of wheels arranged on opposite sides of the wheel base unit <NUM>. To change the direction in which the wheel base unit may travel upon the rail system, one of the sets of wheels 32b is connected to a wheel displacement assembly <NUM>. The wheel displacement assembly is able to lift and lower the connected set of wheels 32b relative to the other set of wheels 32a such that only the set of wheels travelling in a desired direction is in contact with the rail system. The wheel displacement assembly <NUM> is driven by an electric motor <NUM>. Further, two electric motors <NUM>,<NUM>', powered by a rechargeable battery <NUM>, are connected to the set of wheels 32a,32b to move the wheel base unit in the desired direction.

Further referring to <FIG>, the horizontal periphery of the wheel base unit <NUM> is dimensioned to fit within the horizontal area defined by a grid cell, such that two wheel base units may pass each other on any adjacent grid cells of the rail system <NUM>, <NUM>. In other words, the wheel base unit <NUM> may have a footprint, i.e. an extent in the X and Y directions, which is generally equal to the horizontal area of a grid cell, i.e. the extent of a grid cell in the X and Y directions, e.g. as is described in <CIT>.

The wheel base unit <NUM> has a top panel/flange <NUM> (i.e. an upper surface) configured as a connecting interface for connection to a connecting interface of a selected vehicle rescue module <NUM> or container supporting unit <NUM>. The top panel <NUM> have a centre opening <NUM> and features multiple through-holes <NUM> (i.e. connecting elements) suitable for a bolt <NUM> connection via corresponding through-holes <NUM>' in the connecting interface of a vehicle rescue module <NUM> or container supporting unit <NUM>. In other embodiments, the connecting elements of the top panel <NUM> may for instance be threaded pins for interaction with the through-holes <NUM>' of the connecting interface of the vehicle rescue module <NUM> or container supporting unit <NUM>, or vice versa. The presence of a centre opening <NUM> is advantageous as it provides access to internal components of the wheel base unit, such as the rechargeable battery <NUM> and an electronic control system <NUM>. The access allows the rechargeable battery <NUM> and the electronic control system <NUM> to be easily connected to a rescue module connected to the wheel base unit <NUM>, thus the vehicle rescue module <NUM> nor container supporting unit <NUM> is not required to have its own dedicated power source and/or control system.

<FIG> show an example of the rescue vehicle <NUM> of <FIG> illustrating step by step the moving of the rotary drive <NUM>' from the stowed vertical to the deployed horizontal position using a pivotable actuator <NUM>' for manipulating the track shift motor of a container handling vehicle <NUM>. <FIG> are two different perspective views of a rescue vehicle <NUM> where the rotary drive <NUM>' for manipulating track shift has been pivoted to a deployed horizontal position using a pivotable actuator <NUM>'. In <FIG> the rotary drive <NUM>' is connected to the track shift of the malfunctioning container handling vehicle <NUM> and can manipulate the track shift motor. The other rotary drive <NUM>" for manipulating the lifting frame/gripper motor of a malfunctioning vehicle <NUM> is in the stowed vertical position in all <FIG>.

<FIG> show an example of the rescue vehicle <NUM> of <FIG> for manipulating a lifting frame motor of a container handling vehicle, where in <FIG> the rotary drive <NUM>" for manipulating the lifting frame motor is in a deployed horizontal position actuated by a pivotable actuator <NUM>" but not connected to a container handling vehicle <NUM>, whereas in <FIG> the rotary drive <NUM>" is connected to an interface for winching up the lifting frame motor of the container handling vehicle <NUM> such that the lifting frame (possibly carrying a storage container <NUM>) can be lifted up and above the rail system making it possible to transport the container handling vehicle <NUM>. When the rotary drive <NUM>" is in the stowed position, the rescue vehicle <NUM> has a footprint equal to or less than a grid cell of the rail system and in the deployed position, the rotary drive <NUM>" extend into a neighboring grid cell by being pivoted from the deployed vertical position to the deployed horizontal position. This provides for the possibility that the service vehicle <NUM> does not occupy more than one cell when moving on the rail system.

In the preceding description, various aspects of the delivery vehicle and the automated storage and retrieval 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 system, which are apparent to persons skilled in the art to which the disclosed subject matter pertains, and which fall within the scope of the appended claims, are deemed to lie within the scope of the present invention.

Claim 1:
A rescue system for retrieving a malfunctioning vehicle (<NUM>,<NUM>) from a rail system (<NUM>,<NUM>) of an automated storage and retrieval system (<NUM>), the rail system (<NUM>,<NUM>) comprising a plurality of rails with tracks extending in an X-direction and a plurality of rails with tracks extending in a Y-direction perpendicular to the X-direction, a plurality of remotely operated vehicles (<NUM>,<NUM>,<NUM>) configured to move in the X and Y-directions on the tracks of the rail system,
- a first rescue vehicle (<NUM>) configured to run on the tracks of the rail system (<NUM>,<NUM>), the first rescue vehicle (<NUM>) being provided with a lifting device (<NUM>) on one side of the vehicle (<NUM>), the lifting device (<NUM>) facing for engagement in a first X-direction, and a part of the lifting device (<NUM>) extending into a neighboring cell when the rescue vehicle (<NUM>,<NUM>) is positioned in center of a grid cell;
- a second rescue vehicle (<NUM>) configured to run on the tracks of the rail system (<NUM>,<NUM>), the second rescue vehicle (<NUM>) being provided with a lifting device (<NUM>,<NUM>) on an opposite side of the vehicle (<NUM>), the lifting device (<NUM>) facing for engagement in a second X-direction opposite to the first, and a part of the lifting device (<NUM>) extending into a neighboring cell when the rescue vehicle (<NUM>) is positioned in center of a grid cell;
- wherein the first and second rescue vehicles (<NUM>) are configured to work in tandem so that when one of the plurality of remotely operated vehicles (<NUM>,<NUM>,<NUM>,<NUM>) malfunctions, the first and second rescue vehicles (<NUM>) can position themselves on the rail system (<NUM>,<NUM>) on opposite sides of the malfunctioning vehicle (<NUM>,<NUM>) to engage their respective lifting devices (<NUM>) with the opposite sides of the malfunctioning vehicle (<NUM>,<NUM>) and operate their lifting devices (<NUM>) simultaneously so as to lift the malfunctioning vehicle (<NUM>,<NUM>) off the rail system (<NUM>,<NUM>) and transport the malfunctioning vehicle (<NUM>,<NUM>).