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

The framework structure <NUM> comprises several upright members <NUM> and several horizontal members <NUM> which are supported by the upright members <NUM>. The members <NUM>, <NUM> may typically be made of metal, e.g. extruded aluminium profiles.

The framework structure <NUM> defines a storage grid <NUM> comprising storage columns <NUM> arranged in rows, in which storage columns <NUM> storage containers <NUM>, also known as bins, are stacked one on top of another to form stacks <NUM>. The storage grid <NUM> guards against horizontal movement of the stacks <NUM> of storage containers <NUM>, and guides vertical movement of the containers <NUM>, but does normally not otherwise support the storage containers <NUM> when stacked.

The automated storage and retrieval system <NUM> comprises a rail system <NUM> arranged in a grid pattern across the top of the storage <NUM>, on which rail system <NUM> a plurality of container handling vehicles <NUM>, <NUM> are operated to raise storage containers <NUM> from, and lower storage containers <NUM> into, the storage columns <NUM>, and to transport the storage containers <NUM> above the storage columns <NUM>. The rail system <NUM> comprises a first set of parallel rails <NUM> arranged to guide movement of the container handling vehicles <NUM>, <NUM> in a first direction X across the top of the frame structure <NUM>, and a second set of parallel rails <NUM> arranged perpendicular to the first set of rails <NUM> to guide movement of the container handling vehicles <NUM>, <NUM> in a second direction Y which is perpendicular to the first direction X. In this way, the rail system <NUM> defines grid columns <NUM> above which the container handling vehicles <NUM>, <NUM> can move laterally above the storage columns <NUM>, i.e. in a plane which is parallel to the horizontal X-Y plane.

Each prior art container handling vehicle <NUM>, <NUM> comprises a vehicle body 201a, 301a, and first and second sets of wheels 201b, 301b, 201c, 301c which enable the lateral movement of the container handling vehicles <NUM>, <NUM> in the X direction and in the Y direction, respectively. The first set of wheels 201b, 301b is arranged to engage with two adjacent rails of the first set <NUM> of rails, and the second set of wheels 201c, 301c is arranged to engage with two adjacent rails of the second set <NUM> of rails. Each set of 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 (not shown) 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.

Each prior art container handling vehicle <NUM>, <NUM> comprises a storage compartment or space for receiving and stowing a storage container <NUM> when transporting the storage container <NUM> across the rail system <NUM>.

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 grid column <NUM>, i.e. the extent of a grid column <NUM> in the X and Y directions, e.g. as is described in <CIT>] The term 'lateral' used herein may mean 'horizontal'.

Alternatively, the central cavity container handling vehicles <NUM> may have a footprint which is larger than the lateral area defined by a grid column <NUM>, e.g. as is disclosed in <CIT>.

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

In a storage grid <NUM>, most of the grid columns <NUM> are storage columns <NUM>, i.e. grid columns <NUM> where storage containers <NUM> are stored in stacks <NUM>. However, a grid <NUM> normally has at least one grid column <NUM> which is used not for storing storage containers <NUM>, but which comprises a location where the container handling vehicles <NUM>, <NUM> can drop off and/or pick up storage containers <NUM> so that they can be transported to an access station (not shown) where the storage containers <NUM> can be accessed from outside of the grid <NUM> or transferred out of or into the grid <NUM>. Within the art, such a location is normally referred to as a 'port' and the grid column <NUM> in which the port is located may be referred to as a 'port column' <NUM>, <NUM>. For example, the storage containers <NUM> may be placed in a random or dedicated grid column <NUM> within the storage grid <NUM>, then picked up by any container handling vehicle and transported to a port <NUM>, <NUM> for further transportation to an access station.

When a storage container <NUM> stored in the grid <NUM> disclosed in <FIG> is to be accessed, one of the container handling vehicles <NUM>, <NUM> is instructed to retrieve the target storage container <NUM> from its position in the grid <NUM> and transport it to the drop-off port <NUM>. This operation involves moving the container handling vehicle <NUM>, <NUM> to a grid location above the storage column <NUM> in which the target storage container <NUM> is positioned, retrieving the storage container <NUM> from the storage column <NUM> using the container handling vehicle's <NUM>, <NUM> lifting devices (not shown), and transporting the storage container <NUM> to the drop-off port <NUM>. If the target storage container <NUM> is located deep within a stack <NUM>, i.e. with one or a plurality of other storage containers <NUM> positioned above the target storage container <NUM>, the operation also involves temporarily moving the above-positioned storage containers <NUM> prior to lifting the target storage container <NUM> from the storage column <NUM>. 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 <NUM> to the drop-off port <NUM>, or with one or a plurality of other cooperating container handling vehicles. Alternatively, or in addition, the automated storage and retrieval system <NUM> may have container handling vehicles specifically dedicated to the task of temporarily removing storage containers <NUM> from a storage column <NUM>. Once the target storage container <NUM> has been removed from the storage column <NUM>, the temporarily removed storage containers <NUM> can be repositioned into the original storage column <NUM>. However, the removed storage containers <NUM> may alternatively be relocated to other storage columns.

When a storage container <NUM> is to be stored in the grid <NUM>, one of the container handling vehicles <NUM>, <NUM> is instructed to pick up the storage container <NUM> from the pick-up port <NUM> and transport it to a grid location above the storage column <NUM> where it is to be stored. After any storage containers <NUM> 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 <NUM> may then be lowered back into the storage column <NUM> or relocated to other storage columns.

<FIG> describes a wheel base of a delivery vehicle. The delivery vehicles comprise a base with the same setup of wheels as on the container handling vehicles. The wheel base unit features a wheel arrangement having a first set of wheels for movement in a first direction upon a rail grid (i.e. any of the top rail grid and the transfer rail grid) and a second set of wheels 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. To change the direction in which the wheel base unit may travel upon the rail grid, one of the sets of wheels is connected to a wheel displacement assembly. The wheel displacement assembly is able to lift and lower the connected set of wheels relative to the other set of wheels such that only the set of wheels travelling in a desired direction is in contact with the rail grid. The wheel displacement assembly is driven by an electric motor. Further, two electric motors, powered by a rechargeable battery, are connected to the set of wheels to move the wheel base unit in the desired direction. The horizontal periphery of the wheel base unit is dimensioned to fit within the horizontal area defined by a grid cell of the rail grid such that two-wheel base units may pass each other on any adjacent grid cells of the rail grid. In other words, the wheel base unit 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>.

<CIT> which the EPO identified in the examination procedure as the 'closest prior art', describes, in accordance with its abstract, a support vehicle for performing support operations in an automated storage and retrieval system. It comprises a vehicle body. It comprises a drive system comprising wheels provided in a lower part of the vehicle body, where the drive system being configured to drive the support vehicle along a track system of the automated storage and retrieval system. It comprises a connection system provided on a first side of the support vehicle. 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 present invention also relates to an automated storage and retrieval system.

<CIT> describes, in accordance with its abstract, a human transport device and associated system to transport a user within an active workspace. The human transport device may include a platform to support a user, an enclosure coupled to the platform to surround the user, a drive subsystem to power the human transport device, and a control unit to control the movement of the human transport device in coordination with active mobile drive units moving within the workspace. A system implementing one or more human transport devices may include a management module to direct the movement of the one or more human transport devices and designate one or more areas within the workspace as protected areas. Unauthorized objects may be prohibited from entering the protected areas while the human transport device may be allowed within the protected areas.

A problem with present day solutions of automated storage and retrieval systems is if one of the container handling vehicles breaks down on the grid there is a problem with retrieving it. One used solution is a chair with wheels that an operator sits on and manoeuvres by hand out to the container handling vehicle that has broken down. Using this solution, the operator must transport the container handling vehicle that has broken down back to the service area using man power.

According to the present invention a service vehicle is provided. The service vehicle provides a platform for servicing a container handling vehicle, while on a grid-based rail system of a three-dimensional storage grid of an automated storage system for storing storage containers, wherein the service vehicle comprises two or more wheel modules, each module having a first set of wheels configured to move the vehicle along a first lateral direction (X) of the grid-based rail system and a second set of wheels configured to move the vehicle along a second lateral direction (Y) of the grid-based rail system, the second direction (Y) being perpendicular to the first direction (X), wherein a platform is mounted on the two or more wheel modules and said platform comprises an enclosure that has at least one opening that can be closed by a barrier, and the platform has a set of tracks matching the width of the tracks on the grid.

Further the platform of the service vehicle is supported on at least two wheel modules. The wheel modules may be configured to work together as one master wheel module and one or more slave wheel modules.

The service vehicle may have a platform configured such that a container handling vehicle may be lifted onto the platform by hand, by an operator on the service vehicle. The service vehicle may have a bay that can hold a container handling vehicle while the service vehicle is on the grid. Further the platform of the service vehicle may be sized to accommodate at least one operator using a set of controls, wherein an operator on the service vehicle can control the movement of the service vehicle using the set of controls. Alternatively, or in in addition, the service vehicle may be controlled by a central control center.

The platform may be mounted to the upper surfaces of the wheel modules, for example, four wheel modules each positioned at a corner of the platform, and may comprise a bay for a container handling vehicle that is suspended between the wheel modules. The bay of the service vehicle may comprise part of the platform, for example, a part that is positioned, or can be positioned, lower than the remainder of the platform. The bay may be at a working level substantially corresponding to that of a base of the wheel modules. In this way a panel forming the bay may be positioned with a lower surface as close as possible to the upper surface of the rail system while still ensuring clearance and an upper surface which is only a few millimeters higher depending on the thickness of the panel. The bay may also be mounted to allow it to be lowered to rest on the rail system when it is position next to the container handling vehicle.

In other embodiments, the service vehicle may comprise a bay in the form of a recess provided in the platform that is sized to fit around the container handling vehicle. The recess may comprise a rectangular cut-out of a size corresponding to one or two grid cells.

The wheel modules of the service vehicle may be all of the same type. They may each have a perimeter which corresponds substantially to that of a grid cell of the underlying grid rail system. Each wheel module may comprise a rectangular body provided with eight wheels positioned in pairs on four sides of the body, all arranged within a perimeter of one grid cell. Wheels of one wheel module may be positioned so as to ride in a first track of a double track rail and pass, with a clearance, a wheel module in an adjacent grid cell that has wheels in a second track of the same double track rail. Each wheel module may be of a height which is only marginally taller than that of the wheels. For example, each wheel module may be of a height which is less than half that of the container handling vehicle it is intended to service.

The barrier may include an automated mechanism that prevents the barrier from being opened while the service vehicle is in motion.

The service vehicle may be provided with a communications device that can communicate with a communications device of a container handling vehicle and wherein the communications device of the container handling vehicle may be a wireless communications device. The service vehicle may have further a power connector configured to provide power to a container handling vehicle.

A further embodiment of the present invention may be configured in a system comprising a container handling vehicle and the service vehicle of any of the preceding statements, wherein the container handling vehicle may comprise a receiver and the service vehicle may comprise a transmitter. The container handling vehicle may be configured to receive remote control signals from the transmitter and to manoeuvre the container handling vehicle in response to those remote-control signals.

The service vehicle may be configured such that the platform that is mounted to the wheel modules can be turned <NUM>° in either direction around a vertical axis and relative to the wheel modules. A slewing bearing may be placed between the service platform and the wheel modules and used to allow the service platform to rotate freely in either direction relative to the wheel modules. An electric motor may control the rotation of the platform.

Further the service vehicle may comprise a section of the platform with a height adjuster to lower the section onto rails of the grid. The height adjuster may be either a rack and pinion system or a set of hydraulic lifters.

According to the present invention a method is provided, the method for servicing a container handling vehicle using a service vehicle in an automated storage system comprising a three-dimensional storage grid with a grid-based rail system for storing storage containers, wherein the service vehicle comprises two or more wheel modules, each module having a first set of wheels configured to move the vehicle along a first lateral direction (X) of the grid-rail system, and a second set of wheels configured to move the vehicle along a second lateral direction (Y) of the grid-based rail system, the second direction (Y) being perpendicular to the first direction (X), the service vehicle comprising a platform mounted on the two or more wheel modules, the platform comprising an enclosure that has at least one opening that can be closed by a barrier, and the platform has a set of tracks matching the width of the tracks on the grid, wherein said method comprises the steps of maneuvering the service vehicle along the grid to a location at which the opening of the enclosure is positioned next to the container handling vehicle, opening the barrier of the service vehicle, either manually lifting the container handling vehicle onto the platform or driving the container handling vehicle onto the platform of the service vehicle so that the container handling vehicle is received on the service vehicle and closing the barrier of the service vehicle.

The following drawings are appended to facilitate the understanding of the invention.

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

A typical prior art automated storage and retrieval system <NUM> with a framework structure <NUM> was described in the background section above.

The container handling vehicle rail system <NUM> allows the container handling vehicles <NUM> to move horizontally between different grid locations, where each grid location is associated with a grid cell <NUM>.

In <FIG>, the storage grid <NUM> is shown with a height of eight grid cells <NUM>. It is understood, however, that the storage grid <NUM> can in principle be of any size. The storage grid <NUM> can be considerably wider and/or longer than disclosed in <FIG>. For example, the grid <NUM> may have a horizontal extent of more than 700x700 storage columns <NUM>. Also, the grid <NUM> can be considerably deeper than disclosed in <FIG>. For example, the storage grid <NUM> may be more than twelve grid cells <NUM> deep, i.e. in the Z direction indicated in <FIG>.

<FIG> is a perspective view of a prior art container handling vehicle having a centrally arranged cavity for containing storage containers <NUM> therein.

The central cavity container handling vehicles <NUM> 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 grid column <NUM>, i.e. the extent of a grid column <NUM> in the X and Y directions, e.g. as is described in <CIT>.

<FIG> is a perspective view of a prior art container handling vehicle having a cantilever for containing storage containers <NUM> underneath.

<FIG> describes a wheel module <NUM>. The wheel module <NUM> may be suitable for use as a base of a delivery vehicle, for delivering storage containers on a rail system of a storage grid.

The wheel module <NUM> may comprise the same setup of wheels as on the container handling vehicles. The wheel module <NUM> features a wheel arrangement having a first set of wheels <NUM> for movement in a first direction upon a rail grid (i.e. any of the top rail grid and the transfer rail grid) and a second set of wheels <NUM> 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 module <NUM>. To change the direction in which the wheel module <NUM> may travel upon the rail grid, one of the sets of wheels is connected to a wheel displacement assembly. The wheel displacement assembly is able to lift and lower the connected set of wheels relative to the other set of wheels such that only the set of wheels travelling in a desired direction is in contact with the rail grid. The wheel displacement assembly is driven by an electric motor.

In the embodiment, two electric motors, powered by a rechargeable battery, are connected to the set of wheels to move the wheel module <NUM> in the desired direction.

The horizontal periphery of the wheel module <NUM> may be dimensioned to fit within the horizontal area defined by a grid cell of the rail grid such that two wheel modules <NUM> may pass each other on any adjacent grid cell of the rail grid. In other words, the wheel module <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>.

Each wheel of a set of wheels may be arranged to run along a track of a double-track rail that extends along an edge of a grid cell. The second track of the rail may allow a vehicle to pass in a neighboring grid cell with a clearance between the two vehicles.

<FIG> is a perspective drawing of an exemplary service vehicle <NUM> on wheel modules <NUM> placed on a grid <NUM> with an operator <NUM> on board maneuvering the service vehicle <NUM> towards a container handling vehicle <NUM>, <NUM>. The service vehicle <NUM> comprises a platform <NUM> mounted on four wheel modules <NUM>. An enclosure <NUM> surrounds the platform <NUM>. This enclosure <NUM> comprises a framework of bars. Furthermore, the enclosure <NUM> is made of a transparent material like reinforced glass or plexiglass. The main purpose of the enclosure <NUM> is to protect the operator <NUM> on board the service platform <NUM>. The enclosure <NUM> has at least one opening that allows access to a container handling vehicle. This opening has a closable barrier <NUM>. The closable barrier <NUM> may comprise either one or more doors, e.g., either hinged doors or sliding doors. In yet another embodiment, the barrier <NUM> can be in the form of a drop door. This drop door can have rails or tracks on the inside matching the width and shape of the rails/tracks on the grid. These rails/tracks make it possible to roll the container handling vehicle onboard the service vehicle <NUM>. The barrier, e.g., in the form of a door has an automatic locking mechanism that ensures that the door cannot be opened while the service vehicle <NUM> is in motion. A typical scenario of events is that the service vehicle <NUM> is maneuvered towards the container handling vehicle in question. If the doors are ordinary hinged doors or sliding doors, the doors are opened when the service vehicle <NUM> is positioned next to the container handling vehicle and the container handling vehicle is lifted onto the service vehicle <NUM>. If the service vehicle <NUM> has a drop-down door, the door is dropped down onto the grid. The door is positioned such that the upper most edge of the door is next to the container handling vehicle when it is dropped down. The vehicle is then lifted onto the door and maneuvered, using hand power, on to the platform <NUM> of the service vehicle <NUM>. The service can be performed while the service platform <NUM> is on the grid and the container handling vehicle is placed back on the grid. Alternatively, the container handling vehicle can be transported back to a service station for further repair.

The service platform <NUM> can communicate either wirelessly with the container handling vehicle, or the operator <NUM> can connect the service vehicle <NUM> directly to the container handling vehicle if it is not possible to communicate wirelessly. The operator <NUM> on the service vehicle <NUM> can then remote control the container handling vehicle.

Although it is described here that the platform <NUM> is mounted on four wheel modules <NUM>, the number of modules can vary, there can be any number of modules from two and up. If two wheel modules are used the service platform and the wheel modules may take up <NUM> grid cells. If four wheel modules are used, the service platform and the wheel modules can take up anything from <NUM> grid cells and up and having either a square or rectangular size. Additional number of wheel modules can be used if a longer or wider service vehicle is used.

<FIG> is a perspective view of the service vehicle <NUM> of <FIG> comprising a service platform <NUM> supported on wheel modules <NUM> with the barrier <NUM> open to gain access to the container handling vehicle. In this figure the service vehicle <NUM> has reached the container handling vehicle that has broken down. The operator <NUM> has opened the barrier <NUM> of the enclosure <NUM> to gain access to the container handling vehicle. The operator <NUM> can lift the container handling vehicle onboard the service platform <NUM> of the service vehicle <NUM>. The operator <NUM> can either fix the container handling vehicle on the grid or he/she can transport it back to a service station. There is a benefit for fixing the container handling vehicle on the grid. The benefit is that the container handling vehicle can start operating where it stopped after it has been fixed.

<FIG> is a perspective view of the service vehicle <NUM> of <FIG> comprising a service platform <NUM> on wheel modules <NUM> where the operator <NUM> of the platform <NUM> transfers the container handling robot onto the platform <NUM>. The operator <NUM> can either lift the container handling vehicle onto the platform <NUM> or the operator <NUM> can connect to the container handling vehicle either wired or wirelessly and remotely control the container handling vehicle onto the platform <NUM>.

<FIG> is a perspective view of the service vehicle <NUM> of <FIG> where the container handling vehicle is onboard the platform <NUM>. The platform <NUM> may be equipped with guiding tracks/rails <NUM> to ease the access of the container handling vehicle onto the platform <NUM>. After the first set of wheels of the container handling vehicle has been lifted onto the track/rails in the platform <NUM>, it can be pushed easily all the way in.

As it can be seen in this embodiment the service vehicle <NUM> comprises four wheel modules <NUM> for transporting the operator on the grid. To these wheel modules <NUM> there is mounted a platform <NUM>. The platform <NUM> has two zones where the operator(s) <NUM> are situated, suitable for two operators. Between the two zones where the operators <NUM> are seated there is a space or bay for the container handling vehicle. The space or bay for the container handling vehicle is positioned lower down than the rest of the platform <NUM>. This is in order to make it easier to get the container handling vehicle onto the platform <NUM>. In a preferred embodiment of the present invention the space or bay for the container handling vehicle can be lowered in order to accommodate the container handling vehicle. During travel and when the operator <NUM> is working on the container handling vehicle the space for accommodating the container handling vehicle can be lifted. This allows the operator <NUM> greater access to the container handling vehicle when it is being worked on. Also, lifting the space for the container handling vehicle during travel makes it easier to maneuver the service vehicle <NUM> without the risk of the bottom of the platform hitting the top of the grid. The lifting and lowering of the platform <NUM> can be done, for example, by a rack and pinion system, hydraulics or electrical actuators.

<FIG> is a perspective view of another embodiment of the service vehicle where the platform <NUM> is placed on wheel modules <NUM> and has a bay <NUM> in the form of a recess into which the container handling vehicle fits. The bay <NUM> of the service vehicle <NUM> is of such a size that the container handling vehicle fits into the bay <NUM> with the barrier closed. The benefit of using a bay <NUM> in the form of a recess is that there is no lifting and movement of the container handling vehicle before repairing it, and the container handling vehicle can continue its operation from the exact same place it stopped. Further the bay <NUM> in the form of a recess is beneficial since it allows the operator <NUM> to safely repair the container handling vehicle while the rest of the grid is still operating.

In this embodiment, the platform <NUM> can be turned <NUM>° in either direction around a vertical axis and relative to the wheel modules <NUM>. The platform <NUM> can be turned relative to the wheel modules <NUM> using a slewing bearing mounted between the wheel modules <NUM> and the platform <NUM>. The bearing can be turned by an electric motor. The electric motor turning the platform <NUM> relative to the wheel modules <NUM> can get its power from a set of rechargeable power sources mounted on the service vehicle <NUM>.

Claim 1:
A service vehicle (<NUM>) providing a platform (<NUM>) for servicing a container handling vehicle (<NUM>, <NUM>) while on a grid-based rail system of a three-dimensional storage grid (<NUM>) of an automated storage system (<NUM>) for storing storage containers (<NUM>), wherein the service vehicle (<NUM>) comprises two or more wheel modules, each module having a first set of wheels configured to move the vehicle along a first lateral direction (X) of the grid-based rail system and a second set of wheels configured to move the vehicle along a second lateral direction (Y) of the grid-based rail system, the second direction (Y) being perpendicular to the first direction (X), wherein a platform (<NUM>) is mounted on the two or more wheel modules, characterised in that said platform (<NUM>) comprises an enclosure (<NUM>) that has at least one opening that can be closed by a barrier (<NUM>), and the platform (<NUM>) has a set of tracks (<NUM>) matching the width of the tracks on the grid (<NUM>).