Patent Publication Number: US-2021179351-A1

Title: Support vehicle for performing support operations in an automated storage and retrieval system

Description:
FIELD OF THE INVENTION 
     The present invention relates to a support vehicle for performing support operations in an automated storage and retrieval system. The present invention also relates to an automated storage and retrieval system in which such a support vehicle can be used. 
     BACKGROUND OF THE INVENTION 
       FIG. 1  discloses a typical prior art automated storage and retrieval system  1  with a framework structure  100  and  FIGS. 2 and 3  discloses two different prior art container handling vehicles  201 , 301  suitable for operating on such a system  1 . 
     The framework structure  100  comprises a number of upright members  102  and a number of horizontal members  103  which are supported by the upright members  102 . The members  102 ,  103  may typically be made of metal, e.g. extruded aluminum profiles. 
     The framework structure  100  defines a storage grid  104  comprising storage columns  105  arranged in rows, in which storage columns  105  storage containers  106 , also known as bins, stacked one on top of another to form stacks  107 . Each storage container  106  may typically hold a plurality of product items (not shown), and the product items within a storage container  106  may be identical, or may be of different product types depending on the application. The storage grid  104  guards against horizontal movement of the containers in the stacks  107  of storage containers  106 , and guides vertical movement of the containers  106 , but does normally not otherwise support the storage containers  106  when stacked. 
     The automated storage and retrieval system  1  comprises a rail system  108  arranged in a grid pattern across the top of the storage columns  105 , on which rail system  108  a plurality of container handling vehicles  201 , 301  are operated to raise storage containers  106  from and lower storage containers  106  into the storage columns  105 , and also to transport the storage containers  106  above the storage columns  105 . The rail system  108  comprises a first set of parallel rails  110  arranged to guide movement of the container handling vehicles  201 , 301  in a first direction X across the top of the frame structure  100 , and a second set of parallel rails  111  arranged perpendicular to the first set of rails  110  to guide movement of the container handling vehicles  201 , 301  in a second direction Y which is perpendicular to the first direction X. In this way, the rail system  108  defines grid columns  112  above which the container handling vehicles  201 , 301  can move laterally above the storage columns  105 , i.e. in a plane which is parallel to the horizontal X-Y plane. 
     Each prior art container handling vehicle  201 , 301  comprises a vehicle body  201   a , 301   a , and first and second sets of wheels  201   b , 301   b , 201   c , 301   c  which enable the lateral movement of the container handling vehicles  201 , 301  in the X direction and in the Y direction, respectively. In  FIGS. 2 and 3  two wheels in each set are fully visible. The first set of wheels  201   b , 301   b  is arranged to engage with two adjacent rails of the first set  110  of rails, and the second set of wheels  201   c , 301   c  is arranged to engage with two adjacent rails of the second set  111  of rails. Each set of wheels  201   b , 301   b    201   c , 301   c  can be lifted and lowered, so that the first set of wheels  201   b , 301   b  and/or the second set of wheels  201   c , 301   c  can be engaged with the respective set of rails  110 ,  111  at any one time. 
     Each prior art container handling vehicle  201 , 301  also comprises a lifting device (not shown) for vertical transportation of storage containers  106 , e.g. raising a storage container  106  from, and lowering a storage container  106  into, a storage column  105 . 
     The lifting device comprises one or more gripping/engaging devices (not shown) which are adapted to engage a storage container  106 , and which gripping/engaging devices can be lowered from the vehicle  201 , 301  so that the position of the gripping/engaging devices with respect to the vehicle  201 , 301  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 grid  104 , i.e. the layer immediately below the rail system  108 , Z=2 the second layer below the rail system  108 , Z=3 the third layer etc. In the prior art grid disclosed in  FIG. 1 , Z=8 identifies the lowermost, bottom layer of the grid  104 . Consequently, as an example, and using the Cartesian coordinate system X, Y, Z indicated in  FIG. 1 , the storage container identified as  106 ′ in  FIG. 1  can be said to occupy grid location or cell X=10, Y=2, Z=3, with origo of the coordinate system defined as the upper corner to the right in  FIG. 1  (i.e. where the axis X, Y and Z are drawn). The container handling vehicles  201 , 301  can be said to travel in layer Z=0 and each grid column  112  can be identified by its X and Y coordinates. 
     Each prior art container handling vehicle  201 , 301  comprises a storage compartment or space for receiving and stowing a storage container  106  when transporting the storage container  106  across the top of the grid  104 . The storage space may comprise a cavity arranged centrally within the vehicle body  201   a  as shown in  FIG. 2  and as described in e.g. WO2015/193278A1, the contents of which are incorporated herein by reference. 
       FIG. 3  shows an alternative configuration of a container handling vehicles  301  with a cantilever construction. Such a vehicle is described in detail in e.g. NO317366, the contents of which are also incorporated herein by reference. 
     The central cavity container handling vehicles  201  shown in  FIG. 2  may have a footprint which covers an area with dimensions in the X and Y directions, which is generally equal to the lateral area of a grid column  112 , i.e. the extent of a grid column  112  in 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 central cavity container handling vehicles  101  may have a footprint which is larger than the lateral area defined by a grid column  112 , e.g. as is disclosed in WO2014/090684A1. 
     The rail system  108  may be a single rail system, as is shown in  FIG. 4 . Alternatively, the rail system  108  may be a double rail system, as is shown in  FIG. 5 , thus allowing a container handling vehicle  201 , 301  having a footprint generally corresponding to the lateral area defined by a grid column  112  to travel along a row of grid columns even if another container handling vehicle  101  is positioned above a grid column neighboring that row. Both the single and double rail system forms a grid pattern in the horizontal plane P comprising a plurality of rectangular and uniform grid locations or grid cells  122 , where each grid cell  122  comprises a grid opening  115  being delimited by a pair of tracks  110   a , 110   b  of the first tracks  110  and a pair of tracks  111   a , 111   b  of the second set of tracks  111 . In  FIG. 5  the grid cell  122  is indicated by a dashed box. 
     Each grid cell  122  has a width which is typically within the interval of 30 to 150 cm, and a length which is typically within the interval of 50 to 200 cm. Each grid opening  115  has a width and a length which is typically 2 to 10 cm less than the width and the length of the grid cell  122 . 
     In a storage grid  104 , a majority of the grid columns  112  are storage columns  105 , i.e. grid columns  105  where storage containers  106  are stored in stacks  107 . However, a grid  104  normally has at least one grid column  112  which is used not for storing storage containers  106 , but which comprises a location where the container handling vehicles  201 , 301  can drop off and/or pick up storage containers  106  so that they can be transported to an access station (not shown) where the storage containers  106  can be accessed from outside of the grid  104  or transferred out of or into the grid  104 . Within the art, such a location is normally referred to as a ‘port’ and the grid column  112  in which the port is located may be referred to as a ‘port column’  119 , 120 . 
     The grid  104  in  FIG. 1  comprises two port columns  119  and  120 . The first port column  119  may for example be a dedicated drop-off port column where the container handling vehicles  201 , 301  can drop off storage containers  106  to be transported to an access or a transfer station, and the second port column  120  may be a dedicated pick-up port column where the container handling vehicles  201 , 301  can pick up storage containers  106  that have been transported to the grid  104  from an access or a transfer station. 
     The access station may typically be a picking or a stocking station where product items are removed from or positioned into the storage containers  106 . In a picking or a stocking station, the storage containers  106  are normally never removed from the automated storage and retrieval system  1 , but are returned into the grid  104  once accessed. A port can also be used for transferring storage containers out of or into the grid  104 , e.g. for transferring storage containers  106  to another storage facility (e.g. to another grid or to another automated storage and retrieval system), to a transport vehicle (e.g. a train or a lorry), or to a production facility. 
     A conveyor system comprising conveyors is normally employed to transport the storage containers between the ports  119 , 120  and the access station. 
     If the ports  119 , 120  and the access station are located at different levels, the conveyor system may comprise a lift device with a vertical component for transporting the storage containers  106  vertically between the port  119 , 120  and the access station. 
     The conveyor system may be arranged to transfer storage containers  106  between different grids, e.g. as is described in WO2014/075937A1, the contents of which are incorporated herein by reference. 
     When a storage container  106  stored in the grid  104  disclosed in  FIG. 1  is to be accessed, one of the container handling vehicles  201 , 301  is instructed to retrieve the target storage container  106  from its position in the grid  104  and transport it to the drop-off port  119 . This operation involves moving the container handling vehicle  201 , 301  to a grid location above the storage column  105  in which the target storage container  106  is positioned, retrieving the storage container  106  from the storage column  105  using the container handling vehicle&#39;s  201 , 301  lifting device (not shown), and transporting the storage container  106  to the drop-off port  119 . If the target storage container  106  is located deep within a stack  107 , i.e. with one or a plurality of other storage containers  106  positioned above the target storage container  106 , the operation also involves temporarily moving the above-positioned storage containers prior to lifting the target storage container  106  from the storage column  105 . This step, which is sometimes referred to as “digging” within the art, may be performed with the same container handling vehicle that is subsequently used for transporting the target storage container to the drop-off port  119 , or with one or a plurality of other cooperating container handling vehicles. Alternatively, or in addition, the automated storage and retrieval system  1  may have container handling vehicles specifically dedicated to the task of temporarily removing storage containers from a storage column  105 . Once the target storage container  106  has been removed from the storage column  105 , the temporarily removed storage containers can be repositioned into the original storage column  105 . However, the removed storage containers may alternatively be relocated to other storage columns. 
     When a storage container  106  is to be stored in the grid  104 , one of the container handling vehicles  201 , 301  is instructed to pick up the storage container  106  from the pick-up port  120  and transport it to a grid location above the storage column  105  where it is to be stored. After any storage containers positioned at or above the target position within the storage column stack  107  have been removed, the container handling vehicle  201 , 301  positions the storage container  106  at the desired position. The removed storage containers may then be lowered back into the storage column  105 , or relocated to other storage columns. 
     For monitoring and controlling the automated storage and retrieval system  1 , e.g. monitoring and controlling the location of respective storage containers  106  within the grid  104 , the content of each storage container  106 ; and the movement of the container handling vehicles  201 , 301  so that a desired storage container  106  can be delivered to the desired location at the desired time without the container handling vehicles  201 , 301  colliding with each other, the automated storage and retrieval system  1  comprises a control system which typically is computerized and which typically comprises a database for keeping track of the storage containers  106 . 
     WO2016/120075A1, the contents of which are incorporated herein by reference, shows an example of an automated storage and retrieval system using vehicles with a central cavity. The disclosed container handling vehicles are dimensioned so that they have a footprint, i.e. a contact area against the track system, which has a horizontal area that is equal to the horizontal area of a grid cell. Within the art, such a container handling vehicle, i.e. a container handling vehicle having a footprint with a horizontal area corresponding to the horizontal area of a single grid cell, is sometimes referred to as a “single cell” container handling vehicle. Another single cell container handling vehicle is disclosed in WO2015/193278A1, the contents of which are incorporated herein by reference. 
     The single cell design disclosed in e.g. WO2016/120075A1 and WO2015/193278A1 reduces the space required for the container handling vehicles to travel on the track system, thus allowing more vehicles to operate on the track system without interfering with each other. Further, the stability of the vehicle operation is increased compared to a cantilever vehicle as disclosed in e.g. NO317366. 
     WO 2015140216A1 discloses a robotic service device which are used for several such supporting operations. The robotic service device comprises cleaning equipment (brushes, vacuum cleaner) for cleaning the rail system  108  of the grid. The robotic service device further comprises a connection interface for connection to container handling vehicles in order to rescue them, i.e. to push or pull them to a desired location. It is also shown that a relatively large robotic service device may have a member which can be positioned above the container handling vehicle. Then, a winch may be connected to the top of the container handling vehicle and the container handling vehicle can be elevated up from the rails. Another embodiment shows two robotic service devices with a winch provided on a cross beam connected between the two service devices. Here, the container handling vehicle is lifted up towards the beam by means of the winch. The robotic service device can also be connected to a special-purpose person transporter for moving a person to a desired location above the grid  104   d  for maintenance, service, repair etc. 
     One object of the invention is to provide a flexible support vehicle for such storage systems, i.e. the object is that the same support vehicle should be used for several types of support operations. One example of such a support operation is to move a further vehicle, such as a container handling vehicle, to a predefined location, typically a service area, where the further vehicle can be repaired, maintained or transported further away from the grid. Another example of such a support operation is to clean the grid. Another example of such a support operation is to move a person, equipment (for example tools, spare parts etc.) or other objects from a first location to a second location. 
     Another object of the invention is that the support vehicle should support several types of container handling vehicles. 
     Another object of the invention is that the costs (material handling cost, labor cost) should be low. To achieve this, it is an object that as many parts as possible should be in common with parts of a container handling vehicle. In this way, much of the same production line may be used when manufacturing the support vehicle as when producing the container handling vehicle. In this way, spare parts can be used both for the support vehicle and the container handling vehicle. 
     Another object is to provide the support vehicle with a small footprint on the grid, it should be equal to, or not much larger than the container handling vehicles. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a support vehicle for performing support operations in an automated storage and retrieval system, where the support vehicle comprises:
         a vehicle body;   a drive system comprising wheels provided in a lower part of the vehicle body, the drive system being configured to drive the support vehicle along a track system of the automated storage and retrieval system;   a connection system provided on a first side of the support vehicle;       

     characterized in that
         the connection system comprises a connector member protruding through a aperture of the vehicle body;   the connection system comprises an actuator for moving the connector member in the aperture in relation to the vehicle body.       

     The connector member may have a circular, a triangular, a rectangular or polygonal cross section, or any other shape. The connector member may be provided from the inside of the vehicle body through the aperture and to the outside of the vehicle body. Preferably, the connector member is a connector pin. 
     In one aspect, the connection system is connectable to and disconnectable from a connection interface. 
     In one aspect, the connection interface comprises a keyhole, where the connector member is connectable to and disconnectable from the keyhole. The keyhole may have the shape of door-type of keyhole turned upside-down, i.e. with the larger part of the opening provided lower than the smaller part of the opening. 
     The term “keyhole” is here defined as any type of opening into which the connector member can be inserted into and retrieved from. Preferably, the term “keyhole” is an opening into which the connector member can be inserted into, locked to, unlocked from, and then retrieved from. Preferably, these operations are performed by moving the connector member in relation to the connection interface. 
     The keyhole may be an opening provided in a structure. This structure may be an additional unit connectable to and disconnectable from the support vehicle. The structure may also be a container handling vehicle. Preferably, the structure is a plate-shaped structure such as the wall or body of the additional unit or container handling vehicle. The keyhole is typically provided in an vertical part of the structure. The opening can be circular, semi-circular, keyhole-shaped, triangular, rectangular, polygonal etc. Preferably, the keyhole and the connector member is adapted to each other, in order to ensure that they can be connected to and connected from each other. 
     The support vehicle and the additional unit with its connection interface can be defined as a support system. Alternatively, the additional unit with its connection interface may be defined to be a part of the support vehicle itself, i.e. the support vehicle comprises the connection interface and the support vehicle comprises the additional unit with its connection interface. 
     In one aspect, the aperture is an elongated aperture referred to as a slot. The aperture may here be elongated in a vertical direction or in an inclining direction in the plane of the vertical outside wall or body of the additional unit or container handling vehicle. Alternatively, the aperture can be elongated in a horizontal direction. 
     The aperture can be elongated and the actuator can be a linear actuator for moving the connector member linearly in the elongated aperture. Alternatively, the aperture is an opening for the connector member, and the actuator is a pivoting actuator for pivoting the connector member in relation to the aperture. 
     In one aspect, the connector member is a first connector member and where the connection system further comprises a second connector member, where the first connector member is provided through the first aperture and where the further or second connector member is provided through the second aperture. The two apertures, and hence the two members, are spaced apart from each other. 
     In one aspect, the connector members are connected to each other via a rigid cross member provided on the inside of the vehicle body. 
     In this way, the two connector members can be moved in parallel to each other. This is a preferred solution when the apertures are vertical or substantially vertical. The actuator can be connected to the rigid cross member. Hence, one actuator can be used to move both connector members. Alternatively, there can be several actuators connected to the cross member or directly to each connector member. However, when the aperture is horizontal, then the two connector members can be configured to move towards each other or away from each other. Such a solution may require one actuator for each connector member. The actuator is preferably fixed to the inside of the vehicle body. 
     In one aspect, the connector member comprises a head provided in the end of the member being distal from the vehicle body. 
     In one aspect, the head is provided for contact with a rear side of the connection interface. 
     In one aspect, the head is protruding from the member in a direction perpendicular to a longitudinal axis of the connector member. 
     The head may be provided as an enlarged section of the connector member itself, i.e. for example like a commonly known threaded bolt or screw with a bolt or screw head. Alternatively, the head may be formed by providing a notch in the connector member itself, thereby separating the connector member into two separate sections, a distal section forming the head and a proximal section. 
     The head is configured to be inserted into the keyhole of the connection interface and is configured to be provided in contact with the rear side of the connection interface. This is referred to as a connected or locked state, in which the support vehicle may move the connection interface forward, rearward and sideways. It should be noted that the embodiment of the connection system having a connector member without a head will be able to move the connection interface forward (by pushing) and sideways (by dragging the connection interface along the support vehicle). However, rearward movement will be difficult, as the connector member will be pulled out of the keyhole of the connection interface. 
     In one aspect, the connection system comprises a first contact body connected to the connector member or to the vehicle body at a horizontal distance from the head, where a surface of the first contact body is provided for contact with a front surface of the connection interface. 
     In one aspect, the connection system comprises a second contact body provided at a vertical distance from the first contact body, where a surface of the second contact body is provided for contact with the front surface of the connection interface. 
     The first and second contact bodies may allow the connection interface to be provided substantially in parallel with the vehicle body. Preferably, both the front surface of the vehicle body into which the apertures are provided, and the connection interface, are oriented vertically. 
     Preferably, the connection system provides a rigid connection between the support vehicle and the connection interface. Hence, when the connection system is connected the connection interface, relative movement between the support vehicle and the connection interface is prevented by the engagement between the connector member and keyhole, and also by the engagement between the contact surfaces of the contact bodies and the front surface of the connection interface. 
     In one aspect, the support vehicle comprises an additional support unit, where the connection interface is fixed to the additional support unit. 
     In one aspect, the additional support unit comprises a further connection system for connection to a container handling vehicle, where the further connection system comprises:
         a wheel actuator for connection to a mechanical interface of the container handling vehicle for adjusting wheel elevation of the container handling vehicle;   a push body for contact with the container handling vehicle when pushed by the support vehicle.       

     In one aspect, the further connection system of the additional supporting unit comprises a pull body for contact with the container handling vehicle when pulled by the support vehicle. 
     The present invention also relates to an automated storage and retrieval system comprising:
         a track system comprising a first set of parallel tracks arranged in a horizontal plane and extending in a first direction and a second set of parallel tracks arranged in the horizontal plane and extending in a second direction which is orthogonal to the first direction, which first and second sets of tracks form a grid pattern in the horizontal plane comprising a plurality of adjacent grid cells, each comprising a grid opening defined by a pair of neighboring tracks of the first set of tracks and a pair of neighboring tracks of the second set of tracks;   a plurality of stacks of storage containers arranged in storage columns located beneath the track system, wherein each storage column is located vertically below a grid opening;   a container handling vehicle for lifting storage containers stacked in the stacks; characterized in that the system comprises a support vehicle and at least one additional support unit for performing support operations in an automated storage and retrieval system, where the support vehicle comprises a connection system connectable to and disconnectable from a connection interface of the additional support unit.       

     The additional support units are special-purpose support units for performing specific support operations. 
     The present invention also relates to an automated storage and retrieval system, where the support vehicle is a support vehicle as defined above. 
     The present invention also relates to an automated storage and retrieval system, where the additional support unit is one of the following:
         an intermediate supporting unit for connecting the support vehicle to a container handling vehicle, where the support vehicle is configured to pull, push or drag the container handling vehicle along the track system to a service area of the system;   a person transporting unit for transporting a person along the track system from the service area to a desired location in the system;   a equipment transporting unit for transporting equipment along the track system from the service area to a desired location in the system;   a cleaning unit for cleaning the track system; or   a counterweight unit for balancing the support vehicle.       

    
    
     
       DETAILED DESCRIPTION 
       Embodiments of the invention will now be described by way of example only and with reference to the enclosed drawings, where: 
         FIG. 1  is a perspective view of a grid of a prior art automated storage and retrieval system; 
         FIG. 2  is a perspective view of a prior art container handling vehicle having a centrally arranged cavity for containing storage containers therein; 
         FIG. 3  is a perspective view of a prior art container handling vehicle having a cantilever for containing storage containers underneath; 
         FIG. 4  is a top view of a prior art single rail grid; 
         FIG. 5  is a top view of a prior art double rail grid; 
         FIG. 6  illustrates a perspective view from below of an exemplary support vehicle; 
         FIG. 7  illustrates a perspective side view of the support vehicle in  FIG. 6 ; 
         FIG. 8  illustrates another perspective view from below of the support vehicle shown in  FIG. 6 ; 
         FIG. 9  illustrates the inside of the support vehicle of  FIG. 6  with the actuators in the lower position; 
         FIG. 10  illustrates the inside of the support vehicle of  FIG. 6  with the actuators on one side in the upper position; 
         FIG. 11  illustrates a perspective view of an exemplary support vehicle using an adaptor to connect to a first type of container handling vehicle; 
         FIG. 12  illustrates a perspective view of the connection interface of the first type of container handling vehicle before being connected to the adapter; 
         FIG. 13  illustrates the support vehicle and adapter of  FIG. 12  being connected to the container handling vehicle; 
         FIG. 14  illustrates a perspective view of an exemplary support vehicle connected to a person transporter unit; 
         FIG. 15  illustrates a perspective view of an exemplary support vehicle connected to tool transporter unit; 
         FIG. 16  illustrates a perspective view of an exemplary support vehicle connected to cleaning unit; 
         FIG. 17 a    illustrates a perspective side view of an exemplary support vehicle connected to a weight unit and adjacent to a second type of container handling vehicle; 
         FIG. 17 b    illustrates another perspective view of the support vehicle of  FIG. 17 a    and the second type of container handling vehicle; 
         FIG. 17 c    illustrates the support vehicle of  FIG. 17 a    being connected to both the weight unit and the second type of container handling vehicle; 
         FIG. 17 d    illustrates how that the support vehicle of  FIG. 17 a    is able to lift the second type of container handling vehicle up from the rails; 
         FIG. 18  illustrates a simplified grid from above, where a service area is indicated in one corner of the grid; 
         FIG. 19 a    illustrates a cross sectional view of an exemplary connection system; 
         FIG. 19 b    illustrates a front view of the connection interface of  FIG. 19   a;    
         FIG. 19 c    illustrates a cross sectional view along line A-A in  FIG. 19   b;    
         FIG. 19 d    illustrates a cross sectional view of some parts of the connection system being in contact with the connection interface; 
         FIG. 20 a - d    illustrate alternative embodiments of the connection system; 
     
    
    
     Initially, it should be mentioned that prior art features of an automated storage and retrieval system  1  are described in the introduction above, including references to documents which are incorporated herein by reference. 
     It is now referred to  FIG. 6-13 . Here, it is shown a support vehicle  20  for performing support operations in the automated storage and retrieval system  1 . 
     The support vehicle  20  comprises a vehicle body  21  with a central cavity  25  ( FIG. 6 ). A drive system  40  is provided in the lower part of the support vehicle  20 . The drive system  40  is configured to drive the support vehicle  20  along the track system  108  of the automated storage and retrieval system  1 . The drive system  40  comprises a motor, typically an electric motor, and a power source, typically a rechargeable battery. The drive system  40  further comprises a first set of wheels  42  and a second set of wheels  44 , where the support vehicle  20  is moving in a first direction (for example X-direction) when the first set of wheels  42  are in contact with the track system  108  and where the support vehicle  20  is moving in a second direction (for example the Y-direction) when the second set of wheels  44  are in contact with the track system  108 . The drive system  40  also comprises an actuator for bringing the desired set of wheels in contact with the track system. The drive system  40  further comprises a control system for controlling the movement of the support vehicle  20  within the system  1 . It should be noted that the drive system  40  of the support vehicle  20  is considered to be known for a person skilled in the art. 
     The support vehicle  20  further comprises a connection system  30  provided on a first side  21 A of the vehicle body  21 . The connection system  30  is connectable to and disconnectable from a connection interface CI, for example a connection interface CI of an additional support unit. The connection system  30  will be described further in detail below. 
     First, it should be noted that the embodiment of the support vehicle  20  shown in the drawings comprises one connection system  30  provided on a first side  21 A of the vehicle body  21  and an additional connection system  30  provided on a second side  21 B, opposite of the first side  21 A. It should be noted that for many of the applications described herein, one such connection system  30  is sufficient. It should however also be noted that it is possible to provide the support vehicle  20  with a corresponding connection system  30  on a third side and/or fourth side. 
     Now, the connection system  30  will be described in detail with reference to  FIG. 9, 10  and  FIGS. 19 a   - 19   d.    
     In  FIG. 19 a   , it is shown that the exemplary connection system  30  comprises a connector member or pin  31  protruding through an aperture or slot  22  of the vehicle body  21 . In the present embodiment, the connector pin  31  has two sections, a first section having a head or pin head  31   a  and a second elongated section or shank  31   b  defined with a longitudinal axis X 31 . The shank  31   b  is cylindrical in the present embodiment. 
     In the present embodiment, the slot  22  is a vertical slot  22 , in which the connector pin  21  can be moved vertically by means of an actuator  34 . The actuator  34  is an electric linear actuator  34 . 
     On the outside of the vehicle body  21 , a first contact body  32  is provided. The first contact body  32  can be connected to the connector pin  31  or to the vehicle body  21  at a horizontal distance from the pin head  31   a . In the present embodiment, the first contact body  32  is connected to and around the connector pin  31 . 
     In addition to the first contact body  32 , the connection system  30  comprises a second contact body  33  provided at a vertical distance from the first contact body  32 . 
     A rigid member  36  is provided on the inside of the vehicle body  21 . The rigid member  36  is used to connect the actuator  34  to the connector pin  31  and also to the first contact body  32 . Moreover, the second contact body  33  is connected to the rigid member  36  by means of a connector  38 . Hence, when the actuator  34  is moving vertically, also the rigid member  36 , the connector pin  31  and the first and second contact bodies  32 ,  33  are moving vertically. 
     In  FIG. 19 a   , the connection system  30  is in its lower or unlocked position. 
     It is now referred to  FIGS. 19 b  and 19 c   , 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 head  31   a  can be easily inserted and a narrower slot KHb above the circular opening KHa into which the shank  31   b  can be moved, but from which the pin head  31   a  cannot easily be retrieved. Hence, when the connection system  30  is in the lower or unlocked position (and the connection interface CI is stationary), the connector pin  31  may be moved into and out from the keyhole KH. 
     It is now referred to  FIG. 19 d   . Here it is shown that the connector pin  31  has been moved into the keyhole KH and then moved upwardly by means of the actuator  34 . This position is referred to as an upper or locked position. In this locked position, if the support vehicle is moved to the left in  FIG. 19 d   , the connection structure CS will be pulled together with the support vehicle  20  as the pin head  31  is 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 system  30  will be free to move out of engagement with the connection interface CI. 
     It should be noted that in  FIG. 19 d   , contact surfaces  32   a ,  33   a  of the first and second contact bodies  32 ,  33  are in contact with a front side FS of the connection structure 
     CS. Hence, the first and second contact bodies  32 ,  33  provide that the connection interface CI is oriented as desired with respect to the vehicle body  21 . Preferably, the connection interface CI is oriented parallel with the side  21 A of the vehicle body  21 . Preferably, both the first side  21 A of the vehicle body  21  and the connection interface CI are oriented vertically as shown in  FIG. 19 a   - d.    
     In  FIG. 19 d    it is also shown that the longitudinal distance Lcs between the contact surface  32   a  of the contact body  32  and the pin head  31   a  is equal to or a little longer than the thickness Tcs of the connection structure CS. 
     It is now referred to  FIGS. 9 and 10 . Here it is shown that the connection system  30  comprises two connector pins  31  on the first side  21   a  of the vehicle body  21 . The two connector pins  31  are provided in two slots  22  in the vehicle body  21 , where the two slots  22  are spaced apart from each other. 
     The further connection system  30  on the second side  21   b  of the vehicle body  21  also comprises two such connector pins  31  provided in two spaced apart slots  22 . 
     The rigid member  36  described above with reference to  FIG. 19 a    is here used as a rigid cross member  36  which is connecting the connector pins  31  to each other. In this way, the two connector pins  31  are moved vertically in parallel. It should be noted that two actuators  34  are connected between the inside of the vehicle body  21  and each cross member  36 . 
     The support vehicle  20  is based on the type of prior art container handling vehicle  201  shown in  FIG. 2 , i.e. a container handling vehicle  201  with a cavity arranged centrally within the vehicle body  201   a . In  FIG. 17 a   , another example of such a container handling vehicle  201  is shown. In  FIG. 17 , the appearance of the support vehicle  20  is even more similar to the appearance of the container handling vehicle  201 . 
     Only minor modifications are needed to manufacture a support vehicle  20  from such a container handling vehicle  201 . One modification is that slots must be provided in the vehicle body  21  and that the different parts of the connection system  30  must be mounted to the vehicle. Preferably, the container lifting device of the prior art container handling vehicle  201  is removed to save costs and also to provide sufficient space for the actuators  34 . In some applications, it may be required to modify the drive system, as the support vehicle  20  may be designed to handle a larger total weight than a typical container handling vehicle. Hence, a more powerful motor of the drive system  40  may 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 actuators  34 . 
     The automated storage and retrieval system  1  may comprise one or more support vehicles  20  and at least one additional support unit. The additional supporting unit comprises a connection interface CI to which the support vehicle  20  can connect to and disconnect from. Together, the support vehicle  20  and the additional supporting units form a support system for an automated storage and retrieval system  1 . 
     In general, the connection system  30  may be configured to be connected to the connection interface CI of the additional support unit by the following operation:
         moving the connector pin  31  to a first (here: lower) position aligned with the keyhole KH of the connection interface CI of the unit;   moving the connector pin  31  horizontally into the keyhole KH by moving the support vehicle  20  along the track system towards the unit;   moving the connector pin  31  to a second (here: upper) position different from the first position.       

     In this second position, movement of the support vehicle  20  away from the unit will cause the unit to be pulled by the support vehicle. Movement of the support vehicle  20  towards the unit will cause the unit to be pushed by the support vehicle. In the two directions mentioned here, the support vehicle  20  and the unit will move along tracks  110  of  FIG. 11 . 
     Movement of the support vehicle in a direction perpendicular to the push/pull direction will cause the unit to be dragged or pushed in parallel with the support vehicle  20 . This last movement will, as described in the introduction above, require that the correct set of wheels become in contact with tracks  111 , or tracks parallel with tracks  111 , in  FIG. 11 . 
     In general, the connection system  30  is configured to be connected from the connection interface CI by the following operation:
         lowering the connector pin  31  to its first (here: lower) position again;   moving the connector pin  31  horizontally out of the keyhole KH by moving the support vehicle  20  along the rails track system  108  away from the unit.       

     It is now referred to  FIG. 18 . Here the storage grid  104  is seen from above, with storage columns  105  and a service area SA adjacent to the storage columns  105 . The service area SA is an area where service, maintenance and repair operations are performed on the vehicles in the system  1 . The track system  108  is at least partially continues into the service area SA. Hence, vehicles can be driven into the storage grid from the service area and out from the storage grid and into the service area. 
     Examples of different support units will be described through the following examples: 
     Example 1 
     It is here referred to  FIGS. 11, 12 and 13 . Here, the support vehicle  20  is connected to an intermediate supporting unit  60 . The purpose of the intermediate supporting unit  60  is to transport a failed container handling vehicle  301  which is stuck in position P 1  in  FIG. 18  and 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 vehicle  301 , it must be moved to the service area. 
     As shown in  FIG. 11 , the intermediate supporting unit  60  comprises a connection interface CI fixed to a rigid framework formed by elongated bar elements  62  protruding away from the connection interface CI and cross bar elements  61  interconnecting the bar elements  62 . In addition, the framework of the unit  60  comprises downwardly protruding supporting elements  64 . 
     The connector pins  31  of the connection system  30  of the support vehicle  20  are connected to the connection interface CI and the connector pins  31  are in their upper and locked position. It can also be seen in  FIG. 11  that the unit  60  is lifted by the support vehicle  20 , i.e. the unit  60  is not in contact with the track system  108 . 
     The distance between the respective downwardly protruding supporting elements  64  are adapted to the track system  108 . Hence, by lowering the connector pins  31  of the support vehicle  20 , the downwardly protruding supporting elements  64  will come into contact with the track system  108  and the support vehicle  20  can disconnect from the unit  60 . The support vehicle  20  can re-connect to the unit  60  by moving towards the unit  60  with its connector pins  31  in their lower position and then elevate the connector pins  31  when they have been inserted into the keyhole of the connection interface again. 
     In  FIG. 11 , it is shown that the additional support unit  60  comprises a further connection system  70  for connection to a container handling vehicle  301 . The connection system  70  comprises a wheel actuator  72  and a push body  74 ,  75  for contact with the container handling vehicle  301  when it is pushed by the support vehicle  20 . In addition, the further connection system  70  comprises a pull body  76  for contact with the container handling vehicle  301  when pulled by the support vehicle  20 . The pull body  76  may be hook or other type of connection interface for connection to an interface of the container handling vehicle  301 . 
     It should be noted that the connection system  30  of the support vehicle  20  in this example may have a third position. In the first position, as described above, the connection system  30  has lowered the unit and the unit is in contact with the track system  108 . Here, the support vehicle may move the connector pin  31  into or out from the keyhole KH of the connection interface CI. In the second position, the connection system  30  has lifted the unit and the unit is no longer in contact with the track system  108 . However, the pull body  76  is not sufficiently elevated to be moved over the vehicle  301 . Hence, to engage the additional connection system  70  with the vehicle  301 , the connector pins  31  and hence the unit  60  is elevated to a third position above the second position. Now, the pull body  76  of the unit can be moved over the vehicle  301  and then the connection system  30  can be lowered to the second position again. Now, the pull body  76  is engaged with the vehicle  301 . 
     To disconnect from the vehicle  301 , the unit  60  is elevated from the third position and moved away from the vehicle  301 , as the pull body  76  is not engaged with the vehicle  301  in the third position. 
     The wheel actuator  72  is connected to a mechanical interface  72   a  of the container handling vehicle  301  for adjusting wheel elevation of the container handling vehicle  301 , i.e. to mechanically control if the wheels should be in contact with tracks  110  or tracks  111  of the track system. The wheel actuator  72  is driven by an electric motor controlled by the control system of the support vehicle  20  or by a control system of the entire system  1 . 
     It should be noted that the length of the elongated bar elements  62  is adapted to the length between the rails  111 . Hence, when moving along tracks  111 , four tracks  11  are in contact with the wheels of the support vehicle  20  and the wheels of the vehicle  301 , while when moving along tracks  110 , the same two tracks are used both by the support vehicle  20  and the vehicle  301 . 
     It should be noted that in this example, no modification of the vehicle  301  is needed. 
     Example 2 
     It is now referred to  FIG. 14 . The additional support unit is here a person transporting unit  60   a  for transporting a person P along the track system  108 , for example between the service area SA and the position P 1  in  FIG. 18 . Also the person transporting unit  60   a  has a drive system with two set of wheels for moving both along tracks  110  and along tracks  111 . The drive system of the unit  60   a  is here controlled by means of communication signals from the control system of the support vehicle  20  or the system  1 . Alternatively, the drive system of the unit and the support vehicle  20  is controlled by means of a user interface of the unit  60   a  itself. 
     In addition, the unit  60   a  has a connection interface CI (not shown in  FIG. 14 ) which are connected to the connection system  30  of the support vehicle  20 . It should be noted that the support vehicle  20  is not intended to lift the unit  60   a  up from the track system  108 , the purpose of the connection system  30  is only to connect to (for pulling, pushing and dragging the unit  60   a ) and to disconnect from the unit  60   a.    
     Example 3 
     It is now referred to  FIG. 15 . The additional support unit is here an equipment transporting unit  60   b  for transporting equipment along the track system  108  for example between the service area SA and the position P 1  in  FIG. 18 . Also the unit  60   b  has a connection interface CI (not shown). 
     The unit  60   b  has no wheels, and the support vehicle  20  is therefore lifting the unit  60   b.    
     Example 4 
     It is now referred to  FIG. 16 . The additional support unit is here a cleaning unit  60   c  for cleaning the track system  108 . Also the unit  60   c  has a connection interface CI (not shown). 
     The cleaning unit  60   c  comprises rotating brushes  81  for brushing the track system  108  when moved by the support vehicle  20  along tracks  110  and tracks  111 . In addition, the cleaning unit  60   c  comprises a vacuum cleaner  82  with a suction nozzle  83  located close to the brushes  81 . 
     The unit  60   c  has no wheels, and the support vehicle  20  is therefore lifting the unit  60   c.    
     Example 5 
     It is now referred to  FIG. 17 a - d   . The additional support unit is here a counterweight unit  60   d  for balancing the support vehicle  20 . The unit  60   d  has a connection interface CI (not shown) which in  FIGS. 17 a  and 17 b    is connected to the connection system  30  provided on the second side  21 B of the vehicle body  21 . The counterweight unit  60   d  is lifted by the support vehicle  20 . 
     The purpose of the counterweight unit  60   d  is to enable the support vehicle  20  to lift and transport a failed container handling vehicle  201  of the type shown in  FIGS. 17 a  and 17 b   . The container handling vehicle  201  is similar to prior art vehicles, with one modification: The container handling vehicle  201  comprises a connection interface CI. In this example, the connection interface CI is provided as two openings in the vehicle body  221 , one opening for each of the connector pins  31  of the connection system  30  on the second side  21 B of the vehicle body  21  of the support vehicle  20 . 
     In  FIG. 17 c   , it is shown that the connector pins  31  of the connection system  30  moved into the openings of the connection interface CI of the vehicle  201 . 
     In  FIG. 17 d   , it is shown that the connection system  30  is in the second (or third) position, lifting the vehicle  201  up from the grid. Due to the counterweight unit  60   d , the support vehicle  20  will not tilt when lifting the vehicle  201 . 
     Alternative Embodiments 
     In the above embodiments, the connector pin  31  including the pin head  31   a  was rotationally symmetrical around its longitudinal axis. 
     It is now referred to  FIG. 20 a - d   , where some examples of alternative embodiments are shown. 
     In  FIG. 20 a   , the connector pin  31  is not rotationally symmetrical, as only the upper part of the pin head  31   a  is protruding upwardly in a direction perpendicular to the longitudinal axis X 31 . Here, the keyhole KH of the connection interface is oval-shaped. 
     In  FIG. 20 b   , the pin head  31   a  is a rectangle protruding up from the connector pin  31 . Here, the keyhole KH of the connection interface is circular. 
     In  FIG. 20 c   , the pin head  31   a  corresponds to the one shown in  FIG. 20 b   . 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. 
     In  FIG. 20 d   , the pin head  31   a  is formed by providing a notch in the connector pin  31  itself, thereby separating the connector pin  31  into two separate sections, a distal section forming the pin head  31   a  and a proximal section  31   b . Here, the keyhole KH of the connection interface is rectangular. 
     It should be noted that all of the above connector pins  31  may 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 actuator  34  may be dependent on, or independent of, the operation of the drive system  40 . In one embodiment, the vertical distance between the slot  22  and the track system will be the same when the support vehicle is moving along tracks  110  and when the support vehicle is moving along tracks  110 . In such a case, the operation of the actuator  34  can be independent from the drive system  40 . However, in case the vertical distance between the slot  22  and the track system is different when the support vehicle is moving along tracks  110  and when the support vehicle is moving along tracks  111  (due to different elevation of the vehicle body  21  and the different sets of wheels), then the actuator may be operated to change the height of the connector pins based on the travel direction. 
     REFERENCE NUMBERS USED DESCRIPTION 
     
         
         ( 1 ) retrieval system 
         ( 20 ) support vehicle 
         ( 21 ) vehicle body 
         ( 21 ) connector pin 
         ( 21 A) first side 
         ( 21 A) second side 
         ( 21 B) second side 
         ( 22 ) slot 
         ( 25 ) central cavity 
         ( 30 ) connection system 
         ( 31 ) connector pin 
         ( 31 ) pin head 
         ( 31   a ) distal section of connector pin, pin head 
         ( 31   b ) proximal section of connector pin, shank 
         ( 32 ) first contact body 
         ( 32   a ) contact surface 
         ( 33 ) second contact body 
         ( 33   a ) contact surface 
         ( 34 ) actuator 
         ( 36 ) rigid member 
         ( 40 ) drive system 
         ( 42 ) (first set of) wheels 
         ( 44 ) (second set of) wheels 
         ( 60   a ) person transporting unit 
         ( 60   b ) equipment transporting unit 
         ( 60   c ) cleaning unit 
         ( 60   d ) counterweight unit 
         ( 61 ) cross bar elements 
         ( 62 ) rigid framework formed by elongated bar elements 
         ( 64 ) downwardly protruding supporting elements 
         ( 70 ) further connection system 
         ( 70 ) connection system 
         ( 72 ) wheel actuator 
         ( 72   a ) mechanical interface 
         ( 74 ) push body 
         ( 75 ) push body 
         ( 76 ) pull body 
         ( 81 ) rotating brushes 
         ( 81 ) brushes 
         ( 82 ) vacuum cleaner 
         ( 83 ) suction nozzle 
         ( 100 ) framework structure 
         ( 101 ) central cavity container handling vehicles 
         ( 101 ) container handling vehicle 
         ( 102 ) upright members 
         ( 103 ) horizontal members 
         ( 104 ) storage grid 
         ( 105 ) storage column(s) 
         ( 106 ) storage container 
         ( 107 ) stacks 
         ( 108 ) track or rail system 
         ( 110 ) first set of parallel rails 
         ( 110   a ) tracks 
         ( 110   b ) tracks 
         ( 111 ) second set of parallel rails 
         ( 111   a ) tracks 
         ( 111   b ) tracks 
         ( 112 ) grid column 
         ( 115 ) grid opening 
         ( 119 ) first port column 
         ( 120 ) second port column 
         ( 122 ) grid cell 
         ( 201 ) container handling vehicles 
         ( 201   a ) vehicle body 
         ( 201   b ,  201   c ,) wheels 
         ( 301 ) container handling vehicle 
         ( 301   a ) vehicle body 
         ( 301   b ,  301   c ) wheels 
         (CI) connection interface 
         (CS) plate-shaped connection structure 
         (CS) connection structure 
         (KH) keyhole 
         (KH) above keyholes 
         (KHa) circular opening 
         (KHb) narrower slot 
         (RS) rear side 
         (FS) front side 
         (SA) service area 
         (P 1 ) position 
         (X 31 ) longitudinal axis