WO2023041743A1

WO2023041743A1 - An energy storage system for a load handling device

Info

Publication number: WO2023041743A1
Application number: PCT/EP2022/075847
Authority: WO
Inventors: Måns Fredrik Jonathan NILSSON; Nashim Imam
Original assignee: Ocado Innovation Limited
Priority date: 2021-09-16
Filing date: 2022-09-16
Publication date: 2023-03-23

Abstract

A load handling device (31) for an automated storage and retrieval system, comprising: a wheel assembly (34) for moving the load handling device (31); a container-receiving space (49) for receiving a storage container (9); container-lifting means (39) configured to lift a storage container (9) from a stack (11) into the container-receiving space (49); a driving mechanism (38) for driving the wheel assembly (34) and/or the container-lifting means (39); a plurality of compartments (50), each of the plurality of compartments (50) comprising an externally accessible aperture (132) being configured to receive an exchangeable rechargeable power source (52), each of the one or more compartments (50) comprising a charge receiving element (158) configured to electrically couple to the exchangeable rechargeable power source (52) when received within the compartment (50); characterised in that a subgroup of the plurality of compartments (50) comprising one or more compartments (50) are each occupied by an exchangeable rechargeable power source (52) so as to provide sufficient power to operate the driving mechanism (38) of the load handling device (31).

Description

AN ENERGY STORAGE SYSTEM FOR A LOAD HANDLING DEVICE

The invention relates to an energy storage system for a load handling device, more specifically to an energy storage system comprising a plurality of exchangeable rechargeable power sources.

BACKGROUND

The claimed invention is intended to provide improvements relating to energy storage systems for load handling devices operating in automated storage and retrieval systems.

Load handling devices are typically powered by rechargeable power sources. The rechargeable power sources, once depleted, need to be recharged in order to permit the load handling device to continue operating. Charging can take a significant amount of time, and reduce the useful operational time of the load handling devices.

When the rechargeable power source is a battery, the relatively long charging time of the battery can be as long as a couple of hours, which represents a significant downtime during which a load handling device remains inactive or inoperative. Where a number of load handling devices are operative in automated storage and retrieval system to fulfil customer orders within a given time slot, having one or more load handling devices remain idle for a significant amount of time has a detrimental impact on the ability of a fulfilment centre or distribution warehouse to fulfil orders in a timely manner. This is particularly the case where the load handling device contributes to a logistical system that provides home delivery of goods to a customer’s premises upon receipt of an order of goods. Here, delivery information containing delivery addresses is used by online retailers such as Amazon and UK’s Ocado to deliver goods to the customer’s delivery address. To mitigate such a problem, online retailers such as UK’s Ocado provide a buffer of load handling devices operative on the grid framework to cater for load handling devices that remain idle for charging. In an extreme case, time slots for the delivery of orders are extended to cater for this downtime.

Typically, load handling devices powered by lithium-ion batteries require a charge of 15 minutes for every 4 hours of discharge. An alternative to charging the rechargeable power source at a charge station is for the rechargeable power source to be exchangeable, so that a depleted rechargeable power source in a load handling device can be exchanged for a fully charged rechargeable power source. Exchanging the rechargeable power source is much faster than charging a rechargeable power source when the rechargeable power source is inside the load handling device, and therefore negates the disadvantages of slow battery charging, reduces downtime, and contributes to the efficient fulfilment of customer orders.

Typically, a load handling device with a depleted rechargeable power source travels to an exchange station, where the depleted rechargeable power source is removed. The load handling device must then travel to a second exchange station in order to be fitted with a fully charged rechargeable power source.

However, when the rechargeable power source is removed from a load handling device, the load handling device temporarily loses its power supply. This poses two problems: power is needed to enable the load handling device to travel to another exchange station in order to receive a new rechargeable power source, and losing power means that the load handling device loses communication with the control system.

To solve these issues, the load handling device can be supplied with an auxiliary power source, both to enable the load handling device to travel to another exchange station and to maintain connection to control system.

In some examples, the rechargeable power source may be removed and a new one fitted at the same exchange station. While this is more efficient than requiring the load handling device to visit two different exchange stations, the exchange still requires several operations (removing the depleted rechargeable power source from the load handling device, moving the depleted rechargeable power source out of the way, installing a new rechargeable power source). An auxiliary power source is still required to keep the load handling device supplied with power during the exchange operation.

WO201 8210923 (AutoStore) discloses a load handling device with a protruding section that protrudes into a neighbouring grid space, where the protruding section comprises a replaceable battery and battery compartment. In one embodiment, the load handling device interfaces with a first charging station to remove a depleted battery and moves under an auxiliary power source to a second charging station to collect a charged battery.

W02019206440A1 (AutoStore) discloses a load handling device with a first section configured to accommodate a storage container, located side-by-side with a second section comprising at least a first battery. The at least first battery can be fixed or exchangeable. A second battery may be arranged in the second section above or below the first battery.

W02019206440A1 (AutoStore) also discloses a capacitor power supply as an auxiliary power source for backup or to power the load handling device when moving between exchange stations during battery exchange operations.

The use of an auxiliary power source, though solving the problem of how to maintain power to the load handling device and how to provide sufficient power to move the load handling device to a second station where a new power source can be supplied, has the disadvantage that the auxiliary power source is an additional component with concomitant costs and maintenance requirements. The requirement for the load handling device to travel to a second station means that an additional move is needed, which further reduces the time for which the load handling device is not fulfilling customer orders, as well as requiring additional power. Also the control system is more complex, with the need for an algorithm to determine the location of a suitable station at which the load handling device can be fitted with a replacement power source.

A load handling device is therefore needed that fulfils the following requirements: a) the load handling device must be supplied with power at all times; b) the process of exchanging a rechargeable power source must be quick and easy; c) the process of exchanging a rechargeable power source must be able to be completed in one visit to one exchange station.

This application claims priority from GB application number GB2113269.1 filed on 16 September 2021 and GB application number GB2201019.3 filed on 26 January 2022. SUMMARY

The invention is a load handling device for an automated storage and retrieval system, comprising: a wheel assembly for moving the load handling device; a container-receiving space for receiving a storage container; a lifting device configured to lift a storage container from a stack into the container-receiving space; a driving mechanism for driving the wheel assembly and/or the lifting device; a plurality of compartments, each of the plurality of compartments comprising an externally accessible aperture being configured to receive an exchangeable rechargeable power source, each of the plurality of compartments 50 comprising a charge receiving element 158 configured to electrically couple to the exchangeable rechargeable power source 52 when received within the compartment 50; characterised in that a subgroup of the plurality of compartments comprising one or more compartments are each occupied by an exchangeable rechargeable power source so as to provide sufficient power to operate the driving mechanism of the load handling device.

One advantage of a plurality of compartments occupied by exchangeable rechargeable power sources is flexibility; at an exchange station the load handling device can exchange one exchangeable rechargeable power source or several, depending on requirements. Power supply to the load handling device can be maintained: if the load handling device has multiple exchangeable rechargeable power sources installed, when an exchangeable rechargeable power source is removed at the exchange station there will still be at least one other exchangeable rechargeable power source providing power to the load handling device during the exchange operation. Even if the load handling device has only one exchangeable rechargeable power source installed, another exchangeable rechargeable power source can be installed in a different compartment before the first exchangeable rechargeable power source is removed, thus maintaining the power supply. In its broadest sense, having a plurality of compartments allows at least one exchangeable rechargeable power source to be simply inserted into at least one vacant compartment of the plurality of compartments to operate the driving mechanism of the load handling device. This can be achieved through a single operation as opposed to multiple operations to remove a depleted rechargeable power source to create a vacant compartment prior to inserting a charged rechargeable power source as found in prior art systems.

Another advantage is that, if the load handling device has multiple exchangeable rechargeable power sources installed, failure of one exchangeable rechargeable power source will not mean that the load handling device is rendered inactive because the other exchangeable rechargeable power sources can provide power to enable the load handling device to travel to an exchange station or maintenance area.

Batteries which are largely based on lithium-ion, nickel-cadmium, nickel-metal hydride, or lithium-ion polymer battery technologies rely on a chemical reaction to store electrical energy. For the purpose of the present invention, the term battery is construed to mean a battery pack consisting of one or more electrochemical cells with external connectors, i.e. positive and negative terminals. An optional external connector may be present on the battery for sending signals regarding the status of the battery. The individual electrochemical cells making up the battery can be connected in series and/or parallel. The effectiveness of these batteries diminishes after repeated charging due to the breakdown of the lithium ion cells, and therefore the ability of the battery to store charge for a prolonged period of time diminishes over time. Exchangeable rechargeable power sources have the advantage that removing the power source is a normal part of the operation of the load handling device rather than a separate maintenance operation, so when an aged battery is to be retired from use it can simply be withdrawn from circulation when removed from the load handling device at an exchange station, without the requirement for an additional maintenance operation.

The plurality of compartments may comprise a first subgroup and a second subgroup of compartments, and the first or second subgroup is vacant when the other of the first or second subgroups is the subgroup of compartments occupied by exchangeable rechargeable power sources. A subgroup of the compartments being vacant has the advantage that the load handling device will always have sufficient space to accept an exchangeable rechargeable power source. When an exchangeable rechargeable power source is to be removed from the load handling device, for example for charging, a vacant compartment enables another exchangeable rechargeable power source to be installed first, so the load handling device never suffers from a drop in available power.

The plurality of compartments may comprise a first subgroup and a second subgroup of compartments, wherein the first or second subgroup, when occupied by exchangeable rechargeable power sources, is configured to provide sufficient power to operate the driving mechanism of the load handling device, and wherein the first and second subgroups share at least one compartment. For example, a load handling device may be provided with three compartments and require two exchangeable rechargeable power sources to operate the driving mechanism. A subgroup of any two of the three compartments, when occupied by exchangeable rechargeable power sources, will be sufficient to operate the driving mechanism. Because there are three compartments, two subgroups of two compartments must necessarily have a compartment in common.

The load handling device may further comprise a control system configured to selectively switch electrical coupling to the driving mechanism between the first subgroup and the second subgroup.

The control system may be further configured to selectively activate or deactivate the electrical coupling of one or more of the plurality of compartments to the driving mechanism.

An electrical coupling is provided from each of the plurality of compartments to the driving mechanism. A switch may be provided within each compartment, and when the switch for a given compartment is in the “on” position or state, an exchangeable rechargeable power source occupying the compartment is electrically coupled to the driving mechanism and can provide power to the driving mechanism. When the switch for a given compartment is in the “off” position or state, an exchangeable rechargeable power source occupying the compartment is not electrically coupled to the driving mechanism of the load handling device. The switch can comprise any suitable mechanism known in the art, for example, mechanical or electronic switches.

One or more of the plurality of compartments may comprise a securing mechanism configured to releasably secure an exchangeable rechargeable power source within the compartment. The control system mechanism may be configured to operate the securing mechanism.

The securing mechanism may provide the electrical coupling between the exchangeable rechargeable power source within the compartment and the driving mechanism. This has the advantage of a simpler construction with fewer parts: instead of two separate systems for securing and for electrically coupling the exchangeable rechargeable power source, one system can perform both functions.

The plurality of compartments may comprise at least four compartments, the first subgroup of the plurality of compartments comprising at least two compartments, and the second subgroup of the plurality of compartments comprising the other of the least four compartments. In the example where there are four compartments, during operation two of the four compartments will be occupied by exchangeable rechargeable power sources and two of the compartments will be vacant. An advantage of having two exchangeable rechargeable power sources powering the driving mechanism of the load handling device at any one time is that if one of the two exchangeable rechargeable power sources fails or becomes depleted, the other exchangeable rechargeable power source is still able to provide power to the load handling device. The present invention is not limited to four compartments and can be any number of compartments such that occupation of a subgroup of the compartments by one or more rechargeable power sources is sufficient to power the load handling device. For the purpose of the present invention, powering the load handling device is construed to mean providing sufficient power to operate the drive mechanism for moving the load handling device on the tracks and/or operating the lifting mechanism for retrieving and lowering a storage container in and out of the grid framework structure.

All of the plurality of compartments may be occupied by exchangeable rechargeable power sources. This may be useful in some circumstances where higher power is required for a shorter period of time, for example if the load handling device is required to handle a particularly heavy load, or to travel at high speeds. The control system may be configured to selectively activate or deactivate the electrical coupling of one or more of the plurality of compartments to the driving mechanism. In another aspect, the invention provides an automated storage and retrieval system, comprising: one or more load handling devices; a track system comprising a first set of tracks extending in a first direction and a second set of tracks extending in a second direction, the second direction being substantially perpendicular to the first direction; a grid framework structure comprising the track system, a plurality of upright columns supporting the track system, and a plurality of stacks of storage containers arranged in storage columns located below the track system; and one or more exchange stations for exchanging the exchangeable rechargeable power sources of the one or more load handling devices.

In another aspect, the invention provides a method for providing power to the load handling device, comprising the following steps: detecting the presence of exchangeable rechargeable power sources in the plurality of compartments; determining which of the plurality of compartments are occupied by exchangeable rechargeable power sources; accepting power from rechargeable power sources in the occupied compartments.

The presence of exchangeable rechargeable power sources may be determined by any suitable detecting means, for example sensors, to determine whether a given compartment is occupied. One or more sensors may be located in each of the plurality compartments.

The invention provides a method for providing power for a load handling device to operate the driving mechanism of the load handling device comprising a plurality of compartments, each of the plurality of compartments being configured to receive an exchangeable rechargeable power source, a subgroup of the plurality of compartments being occupied by one or more exchangeable rechargeable power sources such that one or more of the plurality of compartments are vacant, the method comprising the following steps: inserting one or more exchangeable rechargeable power sources into one or more of the vacant compartments; engaging a securing mechanism for the one or more exchangeable rechargeable power sources; electrically coupling the one or more exchangeable rechargeable power sources to the driving mechanism.

The method further comprises the steps of: disengaging a securing mechanism for one or more exchangeable rechargeable power sources from one or more compartments of the subgroup of compartments; electrically decoupling the one or more exchangeable rechargeable power sources in the one or more compartments of the subgroup of compartments from the driving mechanism; removing the one or more exchangeable rechargeable power sources from the one or more compartments of the subgroup of compartments.

In its broadest sense, the method comprises the step of simply inserting an exchangeable rechargeable power source into the load handling device so as to provide sufficient power to operate the drive mechanism for moving the load handling device on the grid framework structure. Here, a subgroup of the plurality of compartments is already occupied by one or more exchangeable rechargeable power sources such that one or more of the plurality of compartments are vacant. One or more of the vacant compartments can simply be occupied by one or more fully charged exchangeable rechargeable power source when the exchangeable rechargeable power sources occupying the subgroup of compartments become depleted.

The one or more exchangeable rechargeable power sources occupying the subgroup of the plurality of compartments may be depleted, and the one or more exchangeable rechargeable power sources inserted into the vacant compartments may be fully charged so as to provide power to operate the driving mechanism of the load handling device. The advantage of electrically coupling a fully charged exchangeable rechargeable power source before electrically decoupling a depleted exchangeable rechargeable power source is that the power supply to the load handling device is maintained.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in detail with reference to examples, in which:

Figure 1 schematically illustrates a grid framework structure and containers;

Figure 2 schematically illustrates track on top of the grid framework structure illustrated in Figure 1 ;

Figure 3 schematically illustrates load handling devices on top of the grid framework structure illustrated in Figure 1 ;

Figure 4 schematically illustrates a single load handling device with container-lifting means in a lowered configuration;

Figure 5 schematically illustrates cutaway views of a single load handling device with container-lifting means in a raised and a lowered configuration;

Figure 6a schematically illustrates a load handling device with two compartments;

Figure 6b schematically illustrates a load handling device with two compartments, highlighting the first and second subgroups;

Figure 7a schematically illustrates a load handling device with three compartments;

Figure 7b schematically illustrates a load handling device with three compartments, highlighting the first and second subgroups;

Figure 8a schematically illustrates a load handling device with four compartments;

Figure 8b schematically illustrates a load handling device with four compartments, highlighting the first and second subgroups;

Figure 9 (a and b) schematically illustrates a circuit for electrically coupling the compartments in a load handling device to the driving mechanism.

Figure 10 (a and b) schematically illustrates a circuit for electrically coupling the compartments in a load handling device to the driving mechanism.

Figure 11 (a and b) schematically illustrates a circuit for electrically coupling the compartments in a load handling device to the driving mechanism.

Figure 12 schematically illustrates air flow around a load handling device. Figure 13a is a schematic perspective view of a load handling device with an external side wall removed, showing an exchangeable rechargeable power source in a compartment.

Figure 13b is a schematic cross-sectional side view of the load handling device of Figure 13a.

Figure 14a is a schematic perspective view of another load handling device with an external side wall removed, showing an exchangeable rechargeable power source in a compartment.

Figure 14b is a schematic cross-sectional side view of the load handling device of Figure 14a.

Figure 15 is a schematic perspective view of an exchangeable rechargeable power source and a compartment on top of a load handling device.

DETAILED DESCRIPTION

The following embodiments represent the applicant’s preferred examples of how to implement the invention, but they are not necessarily the only examples of how that could be achieved.

Storage and retrieval systems

Figure 1 illustrates a grid framework structure 1 comprising upright members 3 and horizontal members 5, 7 which are supported by the upright members 3. The horizontal members 5 extend parallel to one another and the illustrated x-axis. The horizontal members 7 extend parallel to one another and the illustrated y-axis, and transversely to the horizontal members 5. The upright members 3 extend parallel to one another and the illustrated z-axis, and transversely to the horizontal members 5, 7. The horizontal members 5, 7 form a grid pattern defining a plurality of grid cells. In the illustrated example, storage containers 9 are arranged in stacks 11 beneath the grid cells defined by the grid pattern, one stack 11 of storage containers 9 per grid cell.

Figure 2 shows a large-scale plan view of a section of track structure 13 forming part of the grid framework structure 1 illustrated in Figure 1 and located on top of the horizontal members 5, 7 of the grid framework structure 1 illustrated in Figure 1. The track structure 13 may be provided by the horizontal members 5, 7 themselves (e.g. formed in or on the surfaces of the horizontal members 5, 7) or by one or more additional components mounted on top of the horizontal members 5, 7. The illustrated track structure 13 comprises x-direction tracks 17 and y-direction tracks 19, i.e. a first set of tracks 17 which extend in the x-direction and a second set of tracks 19 which extend in the y-direction, transverse to the tracks 17 in the first set of tracks 17. The tracks 17, 19 define apertures 15 at the centres of the grid cells. The apertures 15 are sized to allow storage containers 9 located beneath the grid cells to be lifted and lowered through the apertures 15. The x-direction tracks 17 are provided in pairs separated by channels 21 , and the y-direction tracks 19 are provided in pairs separated by channels 23. Other arrangements of track structure may also be possible.

Figure 3 shows a plurality of load handling devices 31 moving on top of the grid framework structure 1 illustrated in Figure 1 . The load handling devices 31 , which may also be referred to as robots 31 or bots 31 , are provided with sets of wheels to engage with corresponding x- or y-direction tracks 17, 19 to enable the load handling devices 31 to travel across the track structure 13 and reach specific grid cells. The illustrated pairs of tracks 17, 19 separated by channels 21 , 23 allow load handling devices 31 to occupy (or pass one another on) neighbouring grid cells without colliding with one another.

As illustrated in detail in Figure 4, a load handling device 31 comprises a body 33 in or on which are mounted one or more components which enable the load handling device 31 to perform its intended functions. The body 33 may be an external casing which encloses the internal components of the load handling device 31 , or a frame structure upon which components are mounted. These functions may include moving across the grid framework structure 1 on the track structure 13 and raising or lowering containers 9 (e.g. from or to stacks 11 ) so that the load handling device 31 can retrieve or deposit containers 9 in specific locations defined by the grid pattern.

The load handling device 31 comprises a wheel assembly 34. The embodiment of the load handling device 31 illustrated in Figure 4 comprises first and second sets of wheels 35, 37 which are mounted on the body 33 of the load handling device 31 and enable the load handling device 31 to move in the x- and y-directions along the tracks 17 and 19, respectively. In particular, two wheels 35 are provided on the shorter side of the load handling device 31 visible in Figure 4, and a further two wheels 35 are provided on the opposite shorter side of the load handling device 31 (side and further two wheels 35 not visible in Figure 4). The wheels 35 engage with tracks 17 and are rotatably mounted on the body 33 of the load handling device 31 to allow the load handling device 31 to move along the tracks 17. Analogously, two wheels 37 are provided on the longer side of the bot 31 visible in Figure 4, and a further two wheels 37 are provided on the opposite longer side of the load handling device 31 (side and further two wheels 37 not visible in Figure 4). The wheels 37 engage with tracks 19 and are rotatably mounted on the body 33 of the load handling device 31 to allow the load handling device 31 to move along the tracks 19.

The wheel assembly 34 of the load handing device 31 may be driven by a driving mechanism 38. The driving mechanism 38 may comprise one or more motors.

The load handling device 31 also comprises container-lifting means 39 configured to raise and lower storage containers 9. The illustrated container-lifting means 39 comprises four tapes or reels 41 which are connected at their lower ends to a container-engaging assembly 43. The container-engaging assembly 43 comprises engaging means (which may, for example, be provided at the corners of the assembly 43, in the vicinity of the tapes 41 ) configured to engage with features of the storage containers 9. For instance, the storage containers 9 may be provided with one or more apertures in their upper sides with which the engaging means can engage. Alternatively or additionally, the engaging means may be configured to hook under the rims or lips of the storage containers 9, and/or to clamp or grasp the storage containers 9. The tapes 41 may be wound up or down to raise or lower the containerengaging assembly, as required. The container-lifting means 39 may be driven by a driving mechanism 38. The winding up or down of the tapes 41 of the container-lifting means 39 may be effected or controlled by the driving mechanism 38, which may comprise one or more motors or other means. The same driving mechanism 38 can be used to drive both the wheel assembly 34 and the container-lifting means 39, or separate driving mechanisms may be used.

As can be seen in Figure 5, the body 33 of the illustrated load handling device 31 has an upper portion 45 and a lower portion 47. The upper portion 45 is configured to house one or more operation components (not shown). The lower portion 47 is arranged beneath the upper portion 45. The lower portion 47 comprises a containerreceiving space 49 or cavity for accommodating at least part of a storage container 9 that has been raised by the container-lifting means 39. The container-receiving space 49 is sized such that enough of a storage container 9 can fit inside the cavity to enable the load handling device 31 to move across the track structure 13 on top of grid framework structure 1 without the underside of the storage container 9 catching on the track structure 13 or another part of the grid framework structure 1. When the load handling device 31 has reached its intended destination, the container-lifting means 39 controls the tapes 41 to lower the container-engaging assembly 43 and the corresponding storage container 9 out of the container-receiving space 49 in the lower portion 47 and into the intended position. The intended position may be a stack 11 of storage containers 9 or an egress point of the grid framework structure 1 (or an ingress point of the grid framework structure 1 if the load handling device 31 has moved to collect a container 9 for grid framework in the grid framework structure 1 ). Although in the illustrated example the upper and lower portions 45, 47 are separated by a physical divider, in other embodiments, the upper and lower portions 45, 47 may not be physically divided by a specific component or part of the body 33 of the load handling device 31 .

In some embodiments, the container-receiving space 49 of the load handling device 31 may not be within the body 33 of the bot 31 . For example, in some embodiments, the container-receiving space 49 may be adjacent to the body 33 of the load handling device 31 , e.g. in a cantilever arrangement with the weight of the body 33 of the load handling device 31 counterbalancing the weight of the container to be lifted. In such embodiments, a frame or arms of the container-lifting means 39 may protrude horizontally from the body 33 of the load handling device 31 , and the tapes/reels 41 may be arranged at respective locations on the protruding frame/arms and configured to be raised and lowered from those locations to raise and lower a container into the container-receiving space 49 adjacent to the body 33. The height at which the frame/arms is/are mounted on and protrude(s) from the body 33 of the load handling device 31 may be chosen to provide a desired effect. For example, it may be preferable for the frame/arms to protrude at a high level on the body 33 of the load handling device 31 to allow a larger container (or a plurality of containers) to be raised into the container-receiving space beneath the frame/arms. Alternatively, the frame/arms may be arranged to protrude lower down the body 33 (but still high enough to accommodate at least one container between the frame/arms and the track structure 13) to keep the centre of mass of the load handling device 31 lower when the load handling device 31 is loaded with a container.

To enable the load handling device 31 to move on the different wheels 35, 37 in the first and second directions, the load handling device 31 includes a wheel-positioning mechanism for selectively engaging either the first set of wheels 35 with the first set of tracks 17 or the second set of wheels 37 with the second set of tracks 19. The wheelpositioning mechanism is configured to raise and lower the first set of wheels 35 and/or the second set of wheels 37 relative to the body 33, thereby enabling the load-handling device 31 to selectively move in either the first direction or the second direction across the tracks 17, 19 of the grid framework structure 1 .

The wheel-positioning mechanism may include one or more linear actuators, rotary components or other means for raising and lowering at least one set of wheels 35, 37 relative to the body 33 of the load handling device 31 to bring the at least one set of wheels 35, 37 out of and into contact with the tracks 17, 19. In some examples, only one set of wheels is configured to be raised and lowered, and the act of lowering the one set of wheels may effectively lift the other set of wheels clear of the corresponding tracks while the act of raising the one set of wheels may effectively lower the other set of wheels into contact with the corresponding tracks. In other examples, both sets of wheels may be raised and lowered, advantageously meaning that the body 33 of the load handling device 31 stays substantially at the same height and therefore the weight of the body 33 and the components mounted thereon does not need to be lifted and lowered by the wheel-positioning mechanism.

Compartments for exchangeable rechargeable power sources

Figure 6a schematically illustrates a load handling device 31. In the embodiment illustrated, the wheel assembly 34 comprises two sets of wheels 35, 37. The containerreceiving space 49 for receiving a storage container 9 is located in the lower portion 47 of the body 33 of load handling device. Two compartments 50 are located in the upper portion 45 of the body 33 of the load handling device. Each of the two compartments 50 is configured to receive an exchangeable rechargeable power source 52. The two compartments 50 comprise a first compartment 50a and a second compartment 50b. In the embodiment illustrated in Figure 6a, the first compartment 50a is occupied by an exchangeable rechargeable power source 52, and the second compartment 50b is vacant. The exchangeable rechargeable power source 52 in the first compartment 50a is configured to provide sufficient power to operate the driving mechanism 38 for driving the wheel assembly 34 and/or the driving mechanism 38 for operating the container lifting means 39 of the load handling device 31 .

Although the compartments 50 in Figure 6a are illustrated as being located in the upper portion 45 of the load handling device, the compartments 50 may be located at any position within or on or attached to the load handling device 31 .

In the example shown in Figure 6a, the plurality of compartments 50 for receiving exchangeable rechargeable power sources 52 comprises two compartments, and the subset of compartments that are occupied by exchangeable rechargeable power sources 52 comprises one compartment, leaving one compartment which is vacant. However, in other examples the load handling device 31 may be provided with any number of compartments 50 for receiving exchangeable rechargeable power sources 52, and the subset of compartments that are occupied by exchangeable rechargeable power sources 52 may comprise more than one compartment 50.

For example, Figure 7a illustrates a load handling device where the plurality of compartments 50 comprises three compartments 50a, 50b, 50c, and the subset of compartments that are occupied by exchangeable rechargeable power sources 52 comprises two compartments 50. The first and third compartments 50a and 50c are occupied by exchangeable rechargeable power sources 52, and the second compartment 50b is vacant. In this example, two exchangeable rechargeable power sources 52 provide sufficient power to operate the driving mechanism 38 for driving the wheel assembly 34 and/or the driving mechanism 38 for operating the container lifting means 39 of the load handling device 31 .

Another example is illustrated in Figure 8a, illustrating a load handling device where the plurality of compartments 50 comprises four compartments 50a, 50b, 50c, 50d, and the subset of compartments that are occupied by exchangeable rechargeable power sources 52 comprises two compartments 50. The second and third compartments 50b and 50c are occupied by exchangeable rechargeable power sources 52b and 52c, and the first and fourth compartments 50a and 50d are vacant. In this example, two exchangeable rechargeable power sources 52 provide sufficient power to operate the driving mechanism 38 for driving the wheel assembly 34 and/or the driving mechanism 38 for operating the container lifting means 39 of the load handling device 31 .

When selecting which of several compartments 50 to select, either vacant compartments in which to install an exchangeable rechargeable power source 52, or occupied compartments 50 from which to remove an exchangeable rechargeable power source 52, consideration may be paid to the centre of mass of the loading handling device. For example, in the load handling device illustrated in Figure 8a with four compartments 50 arranged side-by-side, it may be preferable for either the outer two compartments 50a and 50d or the inner two compartments 50b and 50c to be occupied by exchangeable rechargeable power sources 52, in order to keep the combined centre of mass of the two exchangeable rechargeable power sources 52 central in the body 33 of the load handling device 31. If either the two leftmost compartments 50a and 50b, or the two rightmost compartments 50c and 50d, were occupied by exchangeable rechargeable power sources 52, the weight of the exchangeable rechargeable power sources 52 would mean that the combined centre of mass of the two exchangeable rechargeable power sources 52 was not central, which may negatively affect the balance of the load handling device.

The compartments 50 are externally accessible and therefore the exchangeable rechargeable power sources 52 can be conveniently and efficiently exchanged. In cases where the body 33 of the load handling device 31 is an external casing, exchange can take place without having to open the external casing. This also allows the exchangeable rechargeable power sources 52 to be exchanged while the load handling device 31 remains on the track structure 13.

The compartments 50 may be externally accessible from the top or the side of the load handling device 31. The compartments 50 comprise an aperture and the compartments 50 may be configured to removably receive an exchangeable rechargeable power source 52 via the aperture.

In cases where the body 33 of the load handling device 31 is an external casing, the aperture may be defined by the external casing of the load handling device 31 . The aperture may be defined in an external top face or side face of the body 33 of the load handling device 31 . In cases where the body 33 of the load handling device 31 is a framework structure, the aperture may be defined by the framework structure.

The compartments 50 may comprise side walls that define the aperture.

The aperture may be at least partially defined by one or more locating surfaces that taper downwards towards the compartment 50. In this way, the exchangeable rechargeable power source 52 does not need to be precisely aligned with the compartment 50 when the exchangeable rechargeable power source 52 is being inserted into the compartment 50. Alternatively or in addition, the distal end of the exchangeable rechargeable power source 52 may comprise one or more tapered locating surfaces.

The compartment 50 may be located fully within the body 33 of the load handling device 31 such that the exchangeable rechargeable power source 52 is fully located within the body 33 of the load handling device 31 when received in the compartment 50. Alternatively, the compartment 50 may only be partially located within the body 33 of the load handling device 31 such that a portion of the exchangeable rechargeable power source 52 protrudes out of the body 33 when received in the compartment 50. This may aid removal of the exchangeable rechargeable power source 52 from the compartment 50 due to a greater exposed surface area, and may free up space within the body 33 of the load handling device 31 for other components. The compartment 50 may alternatively be located on rather than within the body 33 of the load handling device 31 , i.e. the compartment 50 may be located external to the body 33 of the load handling device 31. For example, the compartment 50 may be located on top of the external body 33.

The compartment 50 may be at least partially defined by an end wall and/or one or more side walls. The compartment 50 may fully or partially physically enclose the exchangeable rechargeable power source 52 from the sides and the distal end. A side wall of the compartment 50 may comprise a groove shaped and configured to receive a corresponding tongue (protrusion) on a side wall of the exchangeable rechargeable power source 52 such that the exchangeable rechargeable power source 52 is constrained to move in a direction parallel to the side wall. With this arrangement, the compartment 50 can restrain movement of the exchangeable rechargeable power source 52 without requiring the perimeter of the exchangeable rechargeable power source 52 to be fully surrounded by side walls.

The plurality of compartments 50 may be all of the same design, or of different designs and/or positions on the load handling device 31 .

Physical design of the compartment

Figures 13a and 13b illustrate a load handling device 31 with an exchangeable rechargeable power source 52. For ease of illustration, only one exchangeable rechargeable power source 52 and one compartment 50 is illustrated. Figure 13a is a perspective view of the load handling device 31 with an exterior side wall removed so that the interior of the load handling device 31 is visible. Figure 13b is a partial cross- sectional side view of the load handling device 31 .

The exchangeable rechargeable power source 52 provides power to one or more electrical components of the load handling device 31 , such as the lifting mechanism and/or the driving assembly. The exchangeable rechargeable power source 52 may be a battery or any other type of suitable power source for delivering electric power, such as a supercapacitor. The exchangeable rechargeable power source 52 comprises an outer casing 204. The outer casing 204 is depicted as having a cuboidal shape but may have other shapes, such as a cylindrical shape. To facilitate handling of the exchangeable rechargeable power source 52 by a human hand or robotic end effector, the outer casing 204 may comprise one or more gripping features 206, e.g. protrusions and/or recesses.

The load handling device 31 further comprises an externally accessible power source compartment 50, i.e. the compartment 50 can be accessed from outside the body 33 of the load handling device 31 . The compartment 50 is configured to removably receive the exchangeable rechargeable power source 52 in a vertical direction. Although illustrated as vertical in this particular example, in other examples the compartment 50 may be configured to receive the exchangeable rechargeable power source 52 in a horizontal direction, or in any other direction. In this illustrated example, the compartment 50 is fully located within the upper portion 45 of the body 33 of the load handling device 31 such that the exchangeable rechargeable power source 52 is fully received within the body 33 of the load handling device 31 . In this illustrated example, the compartment 50 is defined by side walls 154 and a bottom wall 152 configured to separate the exchangeable rechargeable power source 52 from other components inside the upper portion 45 of the load handling device 31 . However, the compartment 50 may be only partially defined by side walls and/or a bottom wall, or the compartment 50 may simply be a reserved space in which the exchangeable rechargeable power source 52 can reside. The bottom of the compartment 50 may also be defined by a wall physically dividing the upper portion 45 and the lower portion 47 of the load handling device 31 and one or more sides of the compartment 50 may be defined by an external casing 130 of the load handling device 31 .

The plurality of compartments in the load handling device may be of the same design, or of different designs.

In the illustrated example, the body 33 of the load handling device comprises an external casing 130. In other examples, the body 33 may be a framework or skeleton structure. The illustrated example is an example only, and other designs of load handling device also fall within the scope of the invention. The compartment 50 is shown as being centred horizontally with respect to the load handling device 31 , which helps the load handling device 31 to maintain balance when moving with an exchangeable rechargeable power source 52 in the compartment 50, but the compartment 50 could also be located elsewhere, e.g. towards one horizontal side of the load handling device 31 , or with the aperture 132 on a side face of the load handling device rather than the top face as illustrated in this example.

The compartment 50 further comprises an aperture 132, which in this example is a top-facing opening 132 defined in a top surface 131 of the external casing 130 of the body 33 of the load handling device 31. The top-facing opening 132 is dimensioned such that the compartment 50 can receive the exchangeable rechargeable power source 52 in a vertical direction via the top-facing opening 132. The top-facing opening 132 optionally comprises one or more locating surfaces 134 tapering downwards towards the compartment 50 for guiding the exchangeable rechargeable power source 52 with the compartment 50. By providing the locating surfaces 134, the exchangeable rechargeable power source 52 does not need to be precisely aligned with the compartment 50 when the exchangeable rechargeable power source 52 is being inserted into the compartment 50. Alternatively or in addition, the bottom of the outer casing 204 may comprise one or more tapered surfaces for the same purpose.

Although in this specific example the aperture 132 is a top-facing opening 132 for receiving an exchangeable rechargeable power source 52 in a vertical direction, in other examples the aperture 132 may be a side-facing opening located on the side of the load handling device 31 for receiving an exchangeable rechargeable power source 52 in a horizontal direction. Any suitable location and orientation of the aperture 132 can be used. Different compartments 50 may have apertures with the same orientation, or apertures 132 with different orientations (for example, some apertures may be top-facing openings and some may be side-facing openings).

The exchangeable rechargeable power source 52 in the illustrated example is electrically coupled to the compartment 50 via one or more electrical connectors 210 on the outer casing 204 and one or more electrical connectors 158 in the compartment 50. The electrical connectors 158, 210 are configured to connect when the exchangeable rechargeable power source 52 is vertically received in the compartment 50 and disconnect when the exchangeable rechargeable power source 52 is vertically removed from the compartment 50. As shown in Figure 13b, the electrical connectors 210 of the exchangeable rechargeable power source 52 are located on a downward- facing surface of the bottom wall 208 of the outer casing 204 and the electrical connectors 158 of the compartment 50 are located on an upward-facing surface of the bottom wall 152 of the compartment 50. However, the electrical connectors 158, 210 could be located on any vertically opposed surfaces of the outer casing 204 and the compartment 50 respectively. When the exchangeable rechargeable power source 52 is vertically inserted into the compartment 50, the bottom wall 208 of the outer casing 204 moves towards the bottom wall 152 of the compartment 50 until the electrical connectors 158, 210 are connected.

In this example where the compartment 50 is configured to receive an exchangeable rechargeable power source in the vertical direction, the weight of the exchangeable rechargeable power source 52 helps the vertically-facing electrical connectors 158, 210 connect and remain connected. The electrical connectors may take any form of suitable electrical connector, such as male and female connectors (e.g. pins and corresponding sockets) or electrical contacts.

Alternatively, the electrical connectors 158, 210 may face in opposing horizontal directions. For example, the electrical contacts 158, 210 may be located on a side wall 154 of the compartment 50 and on a side wall 212 of the outer casing 204 and configured such that they couple when the exchangeable rechargeable power source 52 has been received in the compartment 50. For example, the electrical connectors 158 of the compartment 50 may be biased (e.g. spring-biased) towards the side wall 212 of the outer casing 204 and/or the electrical connectors of the exchangeable rechargeable power source 158, 210 may be biased towards the side wall 154 of the compartment 50.

The compartment 50 does not need to be fully contained within the external casing 130 of the load handling device 31. For example, as shown in Figures 14a and 14b, the compartment 50 is only partially located within the external casing 130 of the load handling device 31 such that the exchangeable rechargeable power source 52 protrudes out of the external casing 130 of the load handling device 31 when received in the compartment 50. This may aid in manual or automated removal of the exchangeable rechargeable power source 52 from the compartment 50 due to a greater exposed surface area, and free up room inside the load handling device 31 for other components. Figure 15 shows an alternative example in which the whole compartment 50 is external to the external casing 130 of the load handling device 31. In this example, the compartment 50 is located on the top surface 131 of the external casing 130 of the load handling device 31. The compartment 50 is partially defined by a side wall 154. The side wall 154 comprises a vertically extending groove 156 shaped and configured to vertically receive a corresponding tongue 214 (i.e. a protrusion) on the side wall 212 of the outer casing 204 such that the exchangeable rechargeable power source 52 is constrained from moving in the horizontal direction relative to the compartment 50. In the illustrated example, the tongue 214 and groove 156 have a T-shaped profile, though other profiles are possible to achieve the same effect. In this way, the compartment 50 can restrain horizontal movement of the exchangeable rechargeable power source 52 without requiring side walls that fully enclose the perimeter of the exchangeable rechargeable power source 52.

The example illustrated in Figures 13-15 is not intended to be limiting; other examples may use different configurations and orientations of the compartments 50. Although only one compartment 50 is shown for ease of illustration, the load handling device 31 comprises a plurality of compartments, which may have the same or different designs, locations, and orientations.

Electrical coupling

Each of the plurality of compartments 50 comprises an externally accessible aperture 132 configured to receive an exchangeable rechargeable power source 52. Each of the one or more compartments 50 comprises a charge receiving element to electrically couple to the exchangeable rechargeable power source 52 when received within the compartment 50.

The specific example described above with reference to Figures 13b and 14b shows the electrical coupling being provided by an electrical contact 210 in the exchangeable rechargeable power source 52 and an electrical contact 158 in the compartment 50. The electrical contact 158 is a specific example of a charge receiving element 158, but in other examples other kinds of charge receiving elements may be used.

In some examples the electrical coupling can be wireless coupling, and the charge receiving element 158 in the compartment 50 is a wireless charge receiving element rather than an electrical contact. When an exchangeable rechargeable power source 52 is received within the compartment 50, the wireless charge receiving element in the compartment receives charge wirelessly from a wireless charge transmitting element in the exchangeable rechargeable power source 52.

When electrically coupled to the compartment 50, the exchangeable rechargeable power source 52 may provide power to one or more electrical or electronic components of the load handling device 31 , e.g. the driving assembly and/or the lifting mechanism.

The compartment 50 may be configured to electrically couple to the exchangeable rechargeable power source 52 when the exchangeable rechargeable power source 52 is received into the compartment and electrically uncouple from the exchangeable rechargeable power source 52 when the exchangeable rechargeable power source 52 is removed from the compartment 50. In other words, the action of inserting the exchangeable rechargeable power source 52 into the compartment 50 causes the exchangeable rechargeable power source 52 to automatically electrically couple to the compartment 50.

As described above, the compartment 50 comprises a charge receiving element. In some examples the charge receiving element comprises an electrical connector configured to electrically couple to a corresponding electrical connector of the exchangeable rechargeable power source 52 when the exchangeable rechargeable power source 52 is received into the compartment 50 and electrically uncouple from the electrical connector of the exchangeable rechargeable power source 52 when the exchangeable rechargeable power source 52 is removed out of the compartment 50. The electrical connector of the compartment 50 may comprise a male connector and the electrical connector of the exchangeable rechargeable power source 52 may comprise a female connector or vice versa. The electrical connectors may alternatively comprise electrical contacts.

The electrical connectors of the compartment 50 and the exchangeable rechargeable power source 52 may face in opposing directions. The electrical connector of the compartment 50 may be provided on an end wall of the compartment 50 and the electrical connector of the exchangeable rechargeable power source 52 may be provided on a distal end of the exchangeable rechargeable power source 52. Alternatively, the electrical connectors may be provided on opposing side walls of the compartment 50 and the exchangeable rechargeable power source 52. The electrical connector of the compartment 50 and/or the electrical connector of the exchangeable rechargeable power source 52 may be biased in a direction such that the electrical connectors contact each other when the exchangeable rechargeable power source 52 is inserted into the compartment 50.

Securing mechanism

One or more of the plurality of compartments 50 may comprise a securing mechanism 58 to secure an exchangeable rechargeable power source 52 within the compartment 50. The securing mechanism 58 is used to retain the exchangeable rechargeable power source 52 within the compartment 50 as the load handling device 31 moves. The securing mechanism 58 can comprise any suitable mechanism known in the art, for example, securing pins and/or grippers.

The securing mechanism 58 is configured to releasably secure the exchangeable rechargeable power source 52 in the compartment 50. The securing mechanism 58 helps to keep the exchangeable rechargeable power source 52 within the compartment 50 when the load handling device 31 is moving or if the load handling device 31 falls over.

The compartment 50 may comprise a first locking member located on/in the compartment or on the exchangeable rechargeable power source 52, and a second locking member located on the exchangeable rechargeable power source 52 or on/in the compartment 50 respectively, wherein the first locking member is configured to move between a locking position in which the first locking member blocks the second locking member to prevent the exchangeable rechargeable power source 52 from moving out of the compartment 50, and a release position in which the exchangeable rechargeable power source 52 is free to move out of the compartment 50.

The first and second locking members may comprise blocking surfaces configured to directly oppose each other when the first locking member is in the locking position to prevent the exchangeable rechargeable power source 52 from being removed from the compartment 50. The first locking member may comprise a protrusion (e.g. a pin, bar, hook, etc.) and the second locking member may comprise a recess or a protrusion (e.g. a rim, rib, etc.). The second locking member may be a surface of the exchangeable rechargeable power source 52.

The first locking member may be configured to move linearly between the locking position and the release position. Alternatively, the first locking member may be pivotally mounted and configured to pivotally rotate between the locking position and the release position.

The securing mechanism may comprise an actuator (e.g. an electric actuator) configured to selectively engage and/or disengage the first and second locking members.

The securing mechanism may be configured such that insertion of the exchangeable rechargeable power source 52 into the compartment 50 automatically locks the exchangeable rechargeable power source 52 in the compartment 50, e.g. by a mechanical locking mechanism.

The first locking member may be biased towards the locking position. For example, the first locking member may be biased by a spring, or the first locking member may be made from a resilient material that returns to the locking position after being deformed towards the release position. A surface of the first and/or second locking member may have a geometry (e.g. a tapered surface) such that insertion of the exchangeable rechargeable power source 52 into the compartment 50 causes the second locking member to engage and move the first locking member against the biasing force towards the release position until the second locking member has moved past the first locking member.

The securing mechanism may comprise a release mechanism configured to move the first locking member against the biasing force to the release position when activated. For example, the release mechanism may comprise a release member mechanically linked to the first locking member and configured to move the first locking member against the biasing force towards the release position. For example, the release member may comprise a button configured to move the first locking member to the release position when the button is held down and allow the first locking member to return to the locking position under the biasing force when the button is released. The securing mechanism may be configured to lock the exchangeable rechargeable power source 52 in the compartment 50 when the exchangeable rechargeable power source 52 is rotated about an axis in a first direction relative to the compartment 50 and release the exchangeable rechargeable power source 52 from the power source compartment when the exchangeable rechargeable power source 52 is rotated about the axis in a second direction opposite to the first direction relative to the compartment 50. For example, the securing mechanism may comprise a threaded coupling or a bayonet coupling.

The securing mechanism may be configured to magnetically couple the exchangeable rechargeable power source 52 and the compartment 50. For example, the compartment 50 may comprise an electromagnet and the exchangeable rechargeable power source 52 may comprise a ferromagnetic portion or vice versa, wherein activating the electromagnet prevents the exchangeable rechargeable power source 52 from being removed from the compartment 50, and deactivating the electromagnet allows the exchangeable rechargeable power source 52 to be removed from the compartment 50.

Control system

The load handling device 31 may further comprise a control system 60 configured to selectively switch electrical coupling to the driving mechanism 38 between the first subgroup 54 and the second subgroup 56.

Figures 6b, 7b, and 8b illustrate the examples of Figures 6a, 7a, and 7b respectively with the first and second subgroups 54, 56 highlighted with dashed and dotted lines respectively. In the example illustrated in Figure 6b, the first subgroup 54 (shown by a dashed line) comprises the first compartment 50a, and the second subgroup 56 (shown by a dotted line) comprises the second compartment 50b. In this example, the control system 60 switching electrical coupling to the driving mechanism 38 between the first subgroup 54 and the second subgroup 56 may comprise deactivating the electrical coupling between the first compartment 50a (which is the first subgroup 54) and the driving mechanism 38, and activating the electrical coupling between the second compartment 50b (which is the second subgroup 56) and the driving mechanism 38. Alternatively, the reverse operation comprises the control system activating the electrical coupling between the first compartment 50a (the first subgroup 54) and the driving mechanism 38, and deactivating the electrical coupling between the second compartment 50b (the second subgroup 56) and the driving mechanism 38. Figure 6b illustrates exchangeable rechargeable power sources 52a and 52b in both compartments 50a and 50b, so both the first subgroup 54 and the second subgroup 56 are occupied by exchangeable rechargeable power sources 52. In use, once the control system 60 has switched electrical coupling to the driving mechanism 38 from the first subgroup 54 to the second subgroup 56, so that the first subgroup 54 is no longer electrically coupled to the driving mechanism 38, the exchangeable rechargeable power source 52a may be removed from the compartment 50a in the first subgroup 54.

The control system 60 may control the timing of switching electrical coupling to the driving mechanism 38 from the first subgroup 54 to the second subgroup 56 such that power to the load handling device is maintained at all times. For example, the second subgroup 56 (which may be occupied by fully charged exchangeable rechargeable power sources 52) may be electrically coupled to the driving mechanism 38 before the first subgroup 54 (which may be occupied by depleted exchangeable rechargeable power sources 52) is electrically decoupled from the driving mechanism 38. The control system 60 itself may be provided with power from one or more exchangeable rechargeable power sources 52, or may be provided with a separate power source.

In the example illustrated in Figure 6b the first and second subgroups 54, 56 are mutually exclusive. That is, every compartment 50 of the plurality of compartments belongs to exactly one of the two subgroups 54, 56, and there are no compartments that are common to both subgroups. This is not the case for the example illustrated in Figure 7b, in which the first subgroup and the second subgroup are not mutually exclusive, i.e. the first subgroup 54 and the second subgroup 56 share one compartment. In the example illustrated in Figure 7b the first subgroup 54 (shown by a dashed line) comprises the first compartment 50a and the second compartment 50b. The second subgroup 56 (shown by a dotted line) comprises the second compartment 50b and the third compartment 50c. The second compartment 50b is common to the first subgroup 54 and the second subgroup 56. In this example the load handling device 31 requires two exchangeable rechargeable power sources 52 to operate the driving mechanism 38, so either of the two subgroups, when occupied by exchangeable rechargeable power sources 52, will be sufficient to operate the driving mechanism 38.

In this example, the control system 60 switching electrical coupling to the driving mechanism 38 between the first subgroup 54 and the second subgroup 56 may comprise deactivating the electrical coupling between the first compartment 50a (in the first subgroup 54) and the driving mechanism 38, maintaining the electrical coupling between the second compartment 50b (common to the first subgroup 54 and the second subgroup 56) and the driving mechanism 38, and activating the electrical coupling between the third compartment 50c (in the second subgroup 56) and the driving mechanism 38. Alternatively, the reverse operation comprises the control system activating the electrical coupling between the first compartment 50a (in the first subgroup 54) and the driving mechanism 38, maintaining the electrical coupling between the second compartment 50b (common to the first subgroup 54 and the second subgroup 56) and the driving mechanism 38, and deactivating the electrical coupling between the third compartment 50c (in the second subgroup 56) and the driving mechanism 38. In both cases the electrical coupling between the driving mechanism 38 and the first and third compartments 50a, 50c are either activated or deactivated, and the electrical coupling between the driving mechanism and the second compartment 50b, which is common to both subgroups, is maintained.

The control system may be further configured to selectively activate or deactivate the electrical coupling of one or more of the plurality of compartments to the driving mechanism 38. The control system 60 may comprise a number of switches 62, for example, one switch 62 for each compartment 50. Switches 62 may be any suitable kind of switch, for example electrical or mechanical switches.

Figure 9(a and b) schematically illustrates one possible embodiment of an electrical circuit with switches 62. In the embodiment illustrated in Figure 9(a and b), the plurality of compartments 50 comprises two compartments 50. The first compartment 50a is occupied by an exchangeable rechargeable power source 52 and the second compartment 50b is vacant. An electrical coupling is provided from each of the two compartments 50a, 50b to the driving mechanism 38, such that two separate electrical circuits are provided. A number of individual switches 62 may be provided, which may be electrical or mechanical switches. In the example illustrated in Figure 9(a and b) there are two switches 62a and 62b, the first switch 62a for electrically coupling or decoupling an exchangeable rechargeable power source 52 in the first compartment 50a, and the second switch 62b for electrically coupling or decoupling an exchangeable rechargeable power source 52 in the second compartment 50b. When the switch 62 for a given compartment 50 is in the “on” position or state, an exchangeable rechargeable power source 52 occupying that compartment 50 is electrically coupled to the driving mechanism 38 and can provide power to the driving mechanism 38. When the switch 62 for a given compartment 50 is in the “off” position or state, an exchangeable rechargeable power source 52 occupying that compartment 50 is not electrically coupled to the driving mechanism 38 of the load handling device 31 .

In Figure 9(a), the first switch 62a for the first compartment 50a is in the “on” position, so the exchangeable rechargeable power source 52 occupying the first compartment 50a is supplying the driving mechanism 38 with power. In Figure 9(b), the first switch 62a for the first compartment 50a is in the “off” position, so the exchangeable rechargeable power source 52 occupying the first compartment 50a is not supplying the driving mechanism 38 with power. In both Figure 9(a) and 9(b), the second compartment 50b is vacant, so no power is supplied from the second compartment 50b irrespective of the state of the second switch 62b.

In examples where the subset of compartments 50 that are occupied by exchangeable rechargeable power sources 52 comprises more than one occupied compartment 50, the occupied compartments may be electrically coupled in series or in parallel.

Figure 10(a and b) schematically illustrates an example of a load handling device with three compartments 50, where the occupied compartments are electrically connected in parallel. The first compartment 50a is occupied by a first exchangeable rechargeable power source 52a, the second compartment 50b is occupied by a second exchangeable rechargeable power source 52b, and the third compartment 50c is vacant. Each compartment 50 comprises a switch 62. Each switch 62 can be in one of two positions/states: an “on” state in which an exchangeable rechargeable power source 52 occupying the compartment 50 is electrically coupled to the driving mechanism 38, or an “off” state in which an exchangeable rechargeable power source 52 occupying the compartment 50 is not electrically coupled to the driving mechanism 38.

In the example illustrated in Figure 10(a), the first switch 62a in the first compartment 50a is in the “on” state, the second switch 62b in the second compartment 50b is in the “on” state, and the third switch 62c in the third compartment 50c is in the “off” state. The first exchangeable rechargeable power source 52a occupying the first compartment 50a and the second exchangeable rechargeable power source 52b occupying the second compartment are electrically coupled to each other and to the driving mechanism 38, connected in parallel. The third switch 62c in the third compartment 50c is in the “off” state, meaning that if an exchangeable rechargeable power source 52 were present in the third compartment 50c, it would not be electrically connected to the circuit.

In the example illustrated in Figure 10(b), the first switch 62a in the first compartment 50a is in the “on” state, the second switch 62b in the second compartment 50b is in the “off” state, and the third switch 62c in the third compartment 50c is in the “off” state. The first exchangeable rechargeable power source 52a occupying the first compartment 50a is electrically coupled to the driving mechanism 38. The second exchangeable rechargeable power source 52b occupying the second compartment 50b is not electrically coupled to the driving mechanism 38. Although the second compartment 50b is occupied by the second exchangeable rechargeable power source 52b, the “off” state of the second switch 62b means that the second exchangeable rechargeable power source 52b is not electrically coupled to the driving mechanism and therefore cannot contribute to powering the load handling device.

Figure 11 (a and b) schematically illustrates an example of a load handling device with three compartments 50, where the occupied compartments are electrically connected in series. The first compartment 50a is occupied by a first exchangeable rechargeable power source 52a, the second compartment 50b is occupied by a second exchangeable rechargeable power source 52b, and the third compartment 50c is vacant. Each compartment 50 comprises a switch 62. Each switch can be in one of two positions/states: a first state in which an exchangeable rechargeable power source 52 occupying the compartment 50 is electrically coupled to the driving mechanism 38, or a second state in which an exchangeable rechargeable power source 52 occupying the compartment 50 is not electrically coupled to the driving mechanism 38. When in the second state, a switch allows current to flow through the series circuit, bypassing any exchangeable rechargeable power source 52 in its respective compartment 50.

In the example illustrated in Figure 11 (a), the first switch 62a in the first compartment 50a is in the first state, the second switch 62b in the second compartment 50b is in the first state, and the third switch 62c in the third compartment 50c is in the second state. The first exchangeable rechargeable power source 52a occupying the first compartment 50a and the second exchangeable rechargeable power source 52b occupying the second compartment are electrically coupled, connected to each other and to the driving mechanism 38 in series. The third switch 62c in the third compartment 50c is in the second state, meaning that if an exchangeable rechargeable power source 50 were present in the third compartment 50c, it would not be electrically coupled to the circuit. The third switch 62c in its second state allows current to flow through the series circuit from the two exchangeable rechargeable power sources 52a and 52c to the driving mechanism 38.

In the example illustrated in Figure 11 (b), the first switch 62a in the first compartment 50a is in the first state, the second switch 62b in the second compartment 50b is in the second state, and the third switch 62c in the third compartment 50c is in the second state. The first exchangeable rechargeable power source 52a occupying the first compartment 50a is electrically coupled to the driving mechanism 38. The second exchangeable rechargeable power source 52b occupying the second compartment 50b is not electrically coupled to the driving mechanism 38. The second switch 62b in its second state allows current to flow through the circuit from the two exchangeable rechargeable power source 52a in the first compartment 50a to the driving mechanism 38. Although the second compartment 50b is occupied by the second exchangeable rechargeable power source 52b, the second state of the second switch 62b means that the second exchangeable rechargeable power source 52b is not electrically coupled to the driving mechanism and therefore cannot contribute to powering the load handling device.

The control system 60 determines when to electrically couple or decouple the compartments 50 to or from the driving mechanism 38. This can be done in several ways. For example, when exchanging a depleted exchangeable rechargeable power source 52 for a charged exchangeable rechargeable power source 52, the control system 60 can electrically decouple the depleted exchangeable rechargeable power source 52 and electrically couple the charged exchangeable rechargeable power source 52. Equally, when exchanging a damaged exchangeable rechargeable power source 52 for an undamaged exchangeable rechargeable power source 52, the control system 60 can electrically decouple the damaged exchangeable rechargeable power source 52 and electrically couple the undamaged exchangeable rechargeable power source 52. Alternatively, the control system 60 can electrically couple all available exchangeable rechargeable power sources 52 to the driving mechanism 38 (for example, if the load handling device 31 is about to perform a manoeuvre that requires more power). Or if multiple exchangeable rechargeable power sources 52 are installed on the load handling device 31 but maximum power is not required, the control system 60 can electrically couple the exchangeable rechargeable power source(s) 52 with the highest voltage (and thus the highest charge). This has the additional advantage that exchangeable rechargeable power sources 52 can be prevented from being fully discharged, which may reduce the expected lifetime of the exchangeable rechargeable power source 52.

The control system 60 may also be configured to operate the securing mechanism 58, or the securing mechanism 58 may be operated by a separate controller.

In some examples, the securing mechanism 58 may provide the electrical coupling between the exchangeable rechargeable power sources 52 within the compartments 50 and the driving mechanism 38. This has the advantage of a simpler construction with fewer parts: instead of two separate systems for securing and for electrically coupling the exchangeable rechargeable power sources 52, one system can perform both functions. This enables the exchangeable rechargeable power sources 52 to be installed and removed quickly and conveniently; upon inserting an exchangeable rechargeable power source 52 into the compartment 50 through the aperture, the control system 60 may automatically activate the securing mechanism 58 and electrically couple the exchangeable rechargeable power source 52 with the compartment 50. Arrangements of compartments

The plurality of compartments may be arranged in various different configurations in the load handling device. For example, the compartments may be arranged side by side in the load handling device, or vertically on top of one another in the load handling device. In some examples a combination of these arrangements of compartments may be used, for example a load handling device where the plurality of compartments comprises four compartments may have the compartments arranged both side-by-side and vertically on top of one another, with a first row of two compartments vertically on top of a second row of two compartments.

The plurality of compartments may be configured to permit exchangeable rechargeable power sources to be inserted or removed via an aperture or opening on a side of the load handling device. The aperture is accessible externally of the load handling device. The side of the load handling device may be a lateral side or top side of the load handling device. Each of the plurality of compartments may be provided with a separate aperture, or the same aperture can be used for more than one compartment.

Exchangeable rechargeable power source technologies

The plurality of exchangeable rechargeable power sources may comprise lithium ion batteries, lithium-ion polymer batteries, lithium-air batteries, lithium-iron batteries, lithium-iron-phosphate batteries, lead-acid batteries, nickel-cadmium batteries, nickel- metal hydride batteries, nickel-zinc batteries, sodium-ion batteries, sodium-air batteries, thin film batteries, smart battery carbon foam-based lead acid batteries, capacitors, supercapacitors, ultracapacitors, lithium capacitors, electrochemical double layer capacitors, electric double layer capacitors, pseudocapacitors, or hybrid capacitors.

It will be appreciated that, where the load handling device is fitted with multiple exchangeable rechargeable power sources, the exchangeable rechargeable power sources may be of the same kind or of different kinds. For example, the load handling device may be fitted with a lithium-ion battery and a supercapacitor. Cooling

The plurality of exchangeable rechargeable power sources may be air cooled. An advantage of housing the exchangeable rechargeable power sources in compartments is that the compartments may be arranged to have gaps between them, to permit the flow of air. As the load handling device moves, the air flows between and around the compartments and cools the exchangeable rechargeable power sources. In some examples the side walls of the load handling device may be provided with vents to facilitate the flow of air through the load handling device and between the compartments.

The load handling device may comprise one or more fans configured to blow air between the plurality of compartments in order to cool the exchangeable rechargeable power sources. In some examples, the fans can be used to increase the airflow to greater flow rates than can be expected from the motion of the load handling device, and to provide airflow when the load handling device is stationary, thus enhancing the cooling effect.

Figure 12 is a schematic illustration of a top view of a load handling device 31 , with three compartments 50a, 50b, 50c occupied by exchangeable rechargeable power sources 52a, 52b, 52c. The direction of travel of the load handling device 31 is illustrated by the arrow 64. The direction of air flow is indicated by the lines 66. As the load handling device moves forwards in the direction indicated by the arrow 64, the air flows around and between the compartments 50 in the load handling device 31. Sidewalls of the load handling device 31 may be provided with holes or vents in order to permit the flow of air through the load handling device.

Exchange stations

The automated storage and retrieval system may be provided with one or more exchange stations, at which depleted exchangeable rechargeable power sources can be removed from the load handling devices, and fully charged exchangeable rechargeable power sources can be installed. The exchangeable rechargeable power sources can be charged at the exchange stations, or alternatively the exchangeable rechargeable power sources can be transported to separate charge stations for charging. The exchange may be effected by robotic means (e.g. by a robot arm), by a human operative, or by any other suitable means.

Method for providing power to the load handling device

In another aspect, the invention provides a method for providing power to the load handling device. The presence of exchangeable rechargeable power sources in the plurality of compartments is detected. A control system may be used, which may be the same control system 60 which is configured to selectively switch electrical coupling to the driving mechanism 38 between the first subgroup 54 and the second subgroup 56 of compartments 50, or may be a separate control system. The presence of exchangeable rechargeable power sources may be detected by any suitable detecting means, for example, sensors. For example, one or more sensors may be located in each of the plurality compartments. The control system determines which of the plurality of compartments are occupied by exchangeable rechargeable power sources. Once the control system has determined which compartments are occupied by exchangeable rechargeable power sources, the driving mechanism accepts power from the exchangeable rechargeable power sources in the occupied compartments.

The invention provides a method for exchanging a first exchangeable rechargeable power source 52a in the load handling device 31 , comprising the following steps. The method will be described with reference to a load handling device 31 with two compartments 50, a first compartment 50a initially occupied by a first exchangeable rechargeable power source 52a, and a second compartment 50b that is initially unoccupied. For example, the first exchangeable rechargeable power source 52a may be depleted of charge and need to be replaced in order to allow the load handling device 31 to continue moving on the track system 13.

Firstly, a second exchangeable rechargeable power source 52b is inserted into the second compartment 50b. For example, the second exchangeable rechargeable power source 52b may be a fully charged exchangeable rechargeable power source. The insertion may take place at an exchange station, and may be carried out by a robot or a human operative. Secondly, a securing mechanism 58 for the second exchangeable rechargeable power source 52b is engaged. This may be done by the control system 60, and is necessary to retain and secure the second exchangeable rechargeable power source 52b in the second compartment 50b.

Thirdly, the second exchangeable rechargeable power source 52b is electrically coupled to the driving mechanism 38. This may be achieved by the control system 60 actuating one or more switches 62.

Fourthly, a securing mechanism 58 for the first exchangeable rechargeable power source 52a is disengaged. This may be done by the control system 60, and is a necessary step before removing the first exchangeable rechargeable power source 52a.

Fifthly, the first exchangeable rechargeable power source 52a is electrically decoupled from the driving mechanism 38. This may be achieved by the control system 60 actuating one or more switches 62.

Sixthly, first exchangeable rechargeable power source 52a is removed from the first compartment 50a of the load handling device 31. The insertion may take place at an exchange station, and may be carried out by a robot or a human operative.

The first exchangeable rechargeable power source may be depleted, and the second exchangeable rechargeable power source may be fully charged. The advantage of electrically coupling a fully charged exchangeable rechargeable power source before electrically decoupling a depleted exchangeable rechargeable power source is that the power supply to the load handling device is maintained.

However, the present invention is not limited to the method steps described above. In the broadest sense of exchanging an exchangeable rechargeable power source, one or more fully charged exchangeable rechargeable power sources can simply be inserted into one or more vacant compartments in the load handling device without the need to remove one or more of the depleted exchangeable rechargeable power sources already occupying compartments in the load handling device. The switching mechanism described above can then switch the power from the one or more depleted exchangeable rechargeable power sources to the fully charged one or more exchangeable rechargeable power sources. Alternatively, the one or more fully charged exchangeable rechargeable power sources can supplement the power from the depleted exchangeable rechargeable power sources to the load handling device.

Definitions

In this document, the language “movement in the n-direction” (and related wording), where n is one of x, y and z, is intended to mean movement substantially along or parallel to the r?-axis, in either direction (i.e. towards the positive end of the r?-axis or towards the negative end of the r?-axis).

In this document, the word “connect” and its derivatives are intended to include the possibilities of direct and indirection connection. For example, “x is connected to y” is intended to include the possibility that x is directly connected to y, with no intervening components, and the possibility that x is indirectly connected to y, with one or more intervening components. Where a direct connection is intended, the words “directly connected”, “direct connection” or similar will be used. Similarly, the word “support” and its derivatives are intended to include the possibilities of direct and indirect contact. For example, “x supports y” is intended to include the possibility that x directly supports and directly contacts y, with no intervening components, and the possibility that x indirectly supports y, with one or more intervening components contacting x and/or y. The word “mount” and its derivatives are intended to include the possibility of direct and indirect mounting. For example, “x is mounted on y” is intended to include the possibility that x is directly mounted on y, with no intervening components, and the possibility that x is indirectly mounted on y, with one or more intervening components.

In this document, the word “comprise” and its derivatives are intended to have an inclusive rather than an exclusive meaning. For example, “x comprises y” is intended to include the possibilities that x includes one and only one y, multiple y’s, or one or more y’s and one or more other elements. Where an exclusive meaning is intended, the language “x is composed of y” will be used, meaning that x includes only y and nothing else.

In this document, the term “fully charged” applied to an exchangeable rechargeable power source means that the exchangeable rechargeable power source is provided with its rated charge. For a battery, this means that the battery voltage is the rated voltage. The term “depleted” applied to an exchangeable rechargeable power source means that there is a predetermined residual charge left in the exchangeable rechargeable power source. For a battery, this means that the battery voltage has dropped below the rated voltage to a predetermined residual voltage.

In this document, the term “exchangeable” means that the exchangeable rechargeable power source is able to be inserted into and removed from the compartment easily through the aperture. Exchanging the exchangeable rechargeable power source is a normal part of the operation of the load handling device, and the compartment has been designed such that an exchangeable rechargeable power source may be easily inserted and removed many times during the lifetime of the load handling device.

Claims

1. A load handling device 31 for an automated storage and retrieval system, comprising: a wheel assembly 34 for moving the load handling device 31 ; a container-receiving space 49 for receiving a storage container 9; container-lifting means 39 configured to lift a storage container 9 from a stack 11 into the container-receiving space 49; a driving mechanism 38 for driving the wheel assembly 34 and/or the containerlifting means 39; a plurality of compartments 50, each of the plurality of compartments 50 comprising an externally accessible aperture 132 being configured to receive an exchangeable rechargeable power source 52, each of the plurality of compartments 50 comprising a charge receiving element 158 configured to electrically couple to the exchangeable rechargeable power source 52 when received within the compartment 50; characterised in that a subgroup of the plurality of compartments 50 comprising one or more compartments 50 are each occupied by an exchangeable rechargeable power source 52 so as to provide sufficient power to operate the driving mechanism 38 of the load handling device 31 .

2. The load handling device 31 of claim 1 , wherein the plurality of compartments 50 comprises a first subgroup 54 and a second subgroup 56 of compartments 50, and the first 54 or second 56 subgroup is vacant when the other of the first 54 or second 56 subgroups is the subgroup of compartments occupied by exchangeable rechargeable power sources 52.

3. The load handling device 31 of claim 1 , wherein the plurality of compartments 50 comprises a first subgroup 54 and a second subgroup 56 of compartments 50, wherein the first 54 or second 56 subgroup, when occupied by exchangeable rechargeable power sources 52, is configured to provide sufficient power to operate the driving mechanism 38 of the load handling device 31 , and wherein the first and second subgroups 54, 56 share at least one compartment 50.

4. The load handling device 31 of claim 2 or claim 3, further comprising a control system 60 configured to selectively switch electrical coupling to the driving mechanism 38 between the first subgroup 54 and the second subgroup 56.

5. The load handling device of claim 4, in which the control system 60 is further configured to selectively activate or deactivate the electrical coupling of one or more of the plurality of compartments 50 to the driving mechanism 38.

6. The load handling device 31 of any preceding claims, wherein one or more of the plurality of compartments 50 comprises a securing mechanism 58 configured to releasably secure an exchangeable rechargeable power source 52 within the compartment 50.

7. The load handling device 31 of claim 6, wherein the securing mechanism 58 provides the electrical coupling between the exchangeable rechargeable power source 52 within the compartment 50 and the driving mechanism 38.

8. The load handling device 31 of any preceding claims, wherein the plurality of compartments 50 comprises at least four compartments 50, the first subgroup 54 of the plurality of compartments 50 comprising at least two compartments 50, and the second subgroup 56 of the plurality of compartments 50 comprises the other of the at least four compartments 50.

9. The load handling device 31 of claim 1 , in which all of the plurality of compartments 50 are occupied by exchangeable rechargeable power sources 52.

10. The load handling device of claim 9, comprising a control system 60 configured to selectively activate or deactivate the electrical coupling of one or more of the plurality of compartments 50 to the driving mechanism 38.

11. An automated storage and retrieval system, comprising: one or more load handling devices 31 as claimed in any preceding claim; a track system 13 comprising a first set of tracks 17 extending in a first direction and a second set of tracks 19 extending in a second direction, the second direction being substantially perpendicular to the first direction; a grid framework structure 1 comprising the track system 13, a plurality of upright columns 3 supporting the track system 13, and a plurality of stacks 11 of storage containers 9 arranged in storage columns 10 located below the track system 13; and one or more exchange stations 68 for exchanging the exchangeable rechargeable power sources 52 of the one or more load handling devices 31 .

12. A method for providing power to the load handling device 31 of any of claims 1 to 10 to operate the driving mechanism 38 of the load handling device 31 , the method comprising the following steps: detecting the presence of exchangeable rechargeable power sources 52 in the plurality of compartments 50; determining which of the plurality of compartments 50 are occupied by exchangeable rechargeable power sources 52; accepting power from rechargeable power sources 52 in the occupied compartments 50.

13. A method for providing power for the load handling device 31 of any of claims 1 to 10 to operate the driving mechanism 38 of the load handling device 31 comprising a plurality of compartments 50, each of the plurality of compartments 50 being configured to receive an exchangeable rechargeable power source 52, a subgroup of the plurality of compartments 50 being occupied by one or more exchangeable rechargeable power sources 52 such that one or more of the plurality of compartments 50 are vacant, the method comprising the following steps: inserting one or more exchangeable rechargeable power sources 52 into one or more of the vacant compartments 50; engaging a securing mechanism 56 for the one or more exchangeable rechargeable power sources 52; electrically coupling the one or more exchangeable rechargeable power sources 52 to the driving mechanism 38.

14. The method of claim 13, further comprising the steps of: disengaging a securing mechanism 54 for one or more exchangeable rechargeable power sources 52 from one or more compartments 50 of the subgroup of compartments; electrically decoupling the one or more exchangeable rechargeable power sources 52 in the one or more compartments 50 of the subgroup of compartments from the driving mechanism 38; removing the one or more exchangeable rechargeable power sources 52 from the one or more compartments 50 of the subgroup of compartments 50.