GB2598899A

GB2598899A - Method of providing electrical power to a battery powered self-propelled vehicle, an energy storage vehicle and a logistics system

Info

Publication number: GB2598899A
Application number: GB2014503.3A
Authority: GB
Inventors: Keene David; Brewerton Simon
Original assignee: Richmond Design and Marketing Ltd
Current assignee: Richmond Design and Marketing Ltd
Priority date: 2020-09-15
Filing date: 2020-09-15
Publication date: 2022-03-23
Also published as: GB202014503D0

Abstract

An energy storage vehicle 500 is used to provide energy to at least one self-propelled work vehicle 100 in its operating environment, such as an electrical airside support vehicle on an airfield. This increases the useful operation time of the work vehicle as it avoids the need to travel to a fixed recharging point. Energy is provided to the energy storage vehicle at a remote energy provision point (e.g. fixed charging point 150). The energy storage vehicle is driven to the operating environment, such as an airfield, whereupon energy is provided to the work vehicle using the energy storage vehicle, thus the work vehicle is charged in-situ in, or close to, its working environment. The energy storage vehicle and/or the work vehicle may be driven autonomously. The work vehicle may be from the group: airside luggage or cargo transport vehicle (e.g. a luggage or cargo dolly); movable aircraft stairs; catering vehicle; honey truck; hydrocarbon fuel bowser; passenger, aircrew or ground crew transport; luggage or cargo handling conveyor belt; scissor lift; de-icer; push back tug; aircraft escort vehicle. A logistics system includes: the energy storage vehicle; a plurality of work vehicles; and a computer device which issues commands to the energy storage vehicle and the work vehicles and assigns tasks to the energy storage vehicle to recharge the work vehicles.

Description

METHOD OF PROVIDING ELECTRICAL POWER TO A BATTERY POWERED SELF-PROPELLED VEHICLE, AN ENERGY STORAGE VEHICLE AND A LOGISTICS SYSTEM

TECHNICAL FIELD

The present invention relates to methods of providing electrical power to a battery powered self-propelled vehicle in an operating environment, reducing inefficiencies in a logistical system comprising a plurality of vehicles, and increasing the useful operational time of electrical airside support vehicles on an airfield. The invention also relates to energy storage vehicles and logistic systems, and particularly, but not exclusively, vehicles and logistic systems for use in airside environments.

BA CKGROUND

Airside operations and other logistical environments, such as warehouse or docksides, often utilise many vehicles for transporting cargo, baggage and sometimes people. The vehicles will often be operational for long shifts and will be in constant use. The vehicles are therefore usually internal combustion engine driven, as refuelling take seconds or at most minutes compared to the hours that are usually required for battery powered vehicles to recharge.

Where battery vehicles are used they are normally only operational over shorter shifts, or are required to be substituted by further vehicles whilst charging. In advanced systems underground inductive charging may be used. This requires a considerable investment and the installation of new infrastructure. Such an upheaval would mean significant loss of time and money for somewhere like an airport, with runways and airside environments unable to be used for weeks and perhaps months.

It is an aim of the invention to solve problems associated with the prior art.

STATEMENTS OF INVENTION

According to an aspect of the invention there is provided a method of providing electrical power to a battery powered self-propelled vehicle operating in in an operating environment. The method comprises providing an energy storage vehicle, providing energy to the energy storage vehicle at a remote energy provision point, driving the energy storage vehicle to an operating environment, and providing energy to a work vehicle operating in the operating environment using the energy storage vehicle.

The energy store may be a chemical energy store, such as a battery or a fuel tank, or a kinetic energy store such as a fly wheel, or any other suitable form of energy storage. Providing energy to the electric work vehicle when the energy store is fuel may comprise burning fuel in an engine of the vehicle to power an electricity generator mounted on the vehicle and then forming an electrical connection between the energy storage vehicle and the work vehicle.

According to an aspect of the invention there is provided a method of providing electrical power to a battery powered self-propelled vehicle in an operating environment. The method comprises providing an electrical energy storage vehicle, providing electrical energy to the energy storage vehicle at a remote energy provision point, driving the electrical energy storage vehicle to an operating environment, and providing electrical energy to an electric work vehicle operating in the operating environment using the electrical energy storage vehicle.

Using an energy storage vehicle to transfer energy from a remote energy provision point improves efficiency (both energy and time) and reduces maintenance requirements. In a situation where there are a plurality of work vehicles, possibly several or tens of them, a fewer number of energy storage vehicles, possibly only a single vehicle, is/are required to travel to and from the energy provision point and the other work vehicles are able to keep working. Less energy and time is spent moving from point to point with multiple vehicles and less overall mileage is accumulated by the vehicles.

By remote it is meant that the energy provision point is spatially separated from the operating environment. The operating environment may be airside at an airport, for example the apron near the runway and terminals, for example at or near aircraft taxiways, runways, stands, jetways, baggage handling halls, etc. The remote energy provision point could be some considerable distance from some of the aircraft stands or jetways, taxiways, runways or baggage handling halls, for example 500m, 1000m, 1500m, 2000m, 2500m, or more.

There may be multiple remote energy provision points and the energy storage vehicle may be provided energy at an energy provision point closest to the operating environment associated with the work vehicles that it is to service, or with current availability (i.e. not currently being used to provide energy to another vehicle), or the remote energy provision point that the energy storage vehicle uses may be determined by an algorithm that uses availability of charging space/refuelling space at the remote energy provision point and proximity to the work vehicles that it will go on to service with its next fuel load/charge.

The method may further comprise receiving a communication comprising an energy request for a work vehicle in the operating environment.

The energy storage vehicle can then possibly limit or control its movements to only responding to requests, further increasing efficiencies (and of course to returning to a remote energy provision point for replenishing with energy).

The method may further comprise assessing an energy level of the work vehicle (or a plurality of work vehicles) and generating the energy request(s) in dependence on a charge state of the work vehicle(s). The energy request(s) may be generated when the charge state of the battery or other electrical power source of a vehicle drops below a threshold.

Assessing an energy level may comprise assessing a current state of charge of a battery of the vehicle. The method may also further comprise assessing a predicted power usage over a next predetermined time period, and generating the energy request in dependence upon when the energy level of the vehicle is predicted to drop below a threshold. The prediction of energy usage of a vehicle, or of a plurality of vehicles, may include using a planned schedule of work activity for the vehicle(s).

Providing energy to the work vehicle may comprise bringing the work vehicle and the energy storage vehicle together and forming an electrical power transfer connection between the energy storage vehicle and the work vehicle in order to charge the work vehicle. The work vehicle may move closer to the energy storage vehicle to meet it part way, or the work vehicle may carry on with its scheduled tasks and the e ergy storage vehicle come completely or substantially to it.

Bringing the energy storage vehicle and work vehicle together may comprise bringing the energy storage vehicle and work vehicle end to end, side to side, or side to end.

Multiple work vehicles may be brought together with the energy storage vehicle.

The electrical connection may be formed using inductive charging. The electrical connection may instead be formed using a physical connection, such as a plug and socket. The physical connection may be made automatically, for example using a robotic arm, or manually, with a ground crew member making the connections.

The energy storage vehicle may be driven autonomously.

The work vehicle may be driven autonomously.

Providing energy to the energy storage vehicle may comprise charging a battery (or batteries) of the energy storage vehicle. Using a battery can remove the fuelling requirements for work vehicles of conventional airside environments. Vehicles can therefore have zero tailpipe emissions making them more suitable for moving between inside and outside environments.

Providing energy to the energy storage vehicle may comprise charging a supercapacitor (or supercapacitors) of the energy storage vehicle. Using a supercapacitor allows for a longer lifetime of the energy storage vehicle and/or reduces its servicing requirements as a supercapacitor is more tolerant of charge and discharge cycles over a battery. A supercapacitor can also accept and deliver charge faster than a battery, allowing for more efficient use of time and higher utilisation of the energy storage vehicle.

Providing energy to the energy storage vehicle may comprise pumping fuel into a fuel tank of the energy storage vehicle. The fuel may be used in an on-board genset (generator set) of the energy storage vehicle for providing electrical power to the work vehicles. Using hydrocarbon fuel can provide a large energy storage density for the energy storage vehicle and can provide for longer energy storage periods over using a super capacitor or a battery.

The method may comprise the electrical energy storage vehicle providing energy to multiple work vehicles in the operational environment.

Charging the work vehicle may takes place whilst the work vehicle is moving and/or whilst it is performing its work task.

Charging the work vehicle may comprise the work vehicle temporarily stopping its work to park and connect with the energy storage vehicle.

The method may comprise bringing the work vehicle and the energy storage vehicle side to side in order to charge the work vehicle.

The method may comprise bringing the work vehicle and the energy storage vehicle end to end in order to charge the work vehicle.

The operating environment may be a work zone within an airside environment.

The remote energy provision point may be located within the airside environment but outside of the operating environment.

The method may further comprise planning a route and/or a schedule for the energy storage vehicle to charge a plurality of work vehicles The work vehicle may be an airside luggage or cargo transport vehicle such as a luggage or cargo dolly.

The work vehicle may be one of the following vehicles: a set of movable aircraft stairs, a catering vehicle, a honey truck (an aircraft human effluent disposal vehicle), a hydrocarbon fuel bowser, a passenger or aircrew or ground crew transport, a luggage or cargo handling conveyor belt, a scissor lift, a de-icer, a push back tug, and an aircraft escort vehicle (e.g. a vehicle adapted to show aircraft a selected runway exit path).

According to another aspect of the invention there is provided a method of reducing inefficiencies in a logistical system comprising a plurality of vehicles. The method comprises: providing an energy storage vehicle, providing energy to the energy storage vehicle at a remote energy provision point, driving the energy storage vehicle to an operating environment, and providing energy to a work vehicle operating in the operating environment using the energy storage vehicle According to another aspect of the invention there is provided an energy storage vehicle for use in the method of any preceding claim. The vehicle comprises: a motor for providing propulsion for the energy storage vehicle, an energy storage means, a first charging apparatus for receiving electrical power from a static charging point, and a second charging apparatus for providing electrical power to further vehicles.

Alternatively the energy storage vehicle may have propulsion means adapted to move it around physically, and an electricity generator that generates electricity for powering electrical work vehicles, and charging apparatus for providing electrical power to other, work vehicles. The electricity generator could be one that converts hydrocarbon fuel, or hydrogen, into electrical power, or possibly solar power into electric& energy, or both. Solar powered generators have their limitations but could be used in some situations, possibly in addition to a hydrocarbon or hydrogen powered generator. The energy storage vehicle could have electrical energy storage means (e.g. a battery or supercapacitor) to store electrical energy that it generates using its generator.

The second charging apparatus may comprise a plurality of charging apparatuses.

At least one and preferably all of the charging apparatuses may be an inductive charging apparatus.

The or each inductive charging apparatus may be mounted in a vertical plane. The electrical connection that is provided to charge the work vehicles may therefore be formed horizontally between vehicles The energy storage vehicle may have at least four sides. A plurality of sides of the energy storage vehicle may have charging apparatus located on them, for example the front and back, or the side, or each side may have a charging apparatus located upon it. At least one of the sides may have a plurality of charging apparatus located upon it.

According to another aspect of the invention there is provided a logistics system comprising: a plurality of work vehicles configured to receive energy from an energy storage vehicle, an energy storage vehicle configured to provide energy to one or more of the plurality of work vehicles, a computer device configured to issue commands to the energy storage vehicle and the plurality of work vehicles. The plurality of work vehicles, the energy storage vehicle and the computer device are in communication and the computer device is configured to assign tasks to the energy storage vehicle to recharge the work vehicles The system may comprise a plurality of energy storage vehicles and each energy storage vehicle may be assigned to a group of work vehicles.

The groupings of the work vehicles into groups are not necessarily fixed and may be changed over time. The energy storage vehicles may be re-tasked to different operating environments and different groups of work vehicles, possibly on the fly as they move around.

The vehicles may be located within an airside environment, Another area of use is in warehouses, possibly automated warehouses, or in ports or railyards for cargo handling The energy storage vehicles and the plurality of work vehicles may be autonomous vehicles.

According to another aspect of the invention there is provided a method of increasing the useful operational time of electrical airside support vehicles on an airfield. The method comprises bringing an electrical charging vehicle to the vicinity of the support vehicle on the airfield and charging the support vehicle in situ in its working environment or close to its working environment, thereby avoiding the need for the support vehicle to spend downtime travelling to a fixed recharging point further away.

The method may comprise charging a plurality of electrical charging vehicles at a charging station, and moving the plurality of charged electrical charging vehicles to a plurality of different, possibly temporary, locations on an airfield. The method may further comprise bringing a plurality of support vehicles to the charging vehicles and charging the support vehicles using the charging vehicles, at least one charging vehicle, and optionally a plurality of them, having a cluster of support vehicles in charging communication with themselves so as to have a single charging vehicle charging more than one support vehicle simultaneously.

The support vehicles can be considered to be work vehicles.

The method may comprise at least the work vehicles and optionally the charging vehicles, being computer controlled and the computer determining the location of the work vehicles and using that to determine which work vehicles will move where to meet which charging vehicle, dependent upon the position of the work/support vehicles, the charge they need, and the charge available in the particular charging vehicle to which they are sent by the computer, and after determining which work/support vehicle will go where, controlling the support/work vehicles to move to the determined location applicable to them.

The charging vehicles may be computer controlled and the computer automatically determines a respective charging location where it is advantageous to send each charging vehicle and automatically moves the charging vehicles to their determined respective charging locations and automatically moves the support vehicles to their determined charging locations and causes the automated charging of the support vehicles.

According to another aspect of the invention there is provided a method of reducing maintenance on airside support vehicles. The method comprises bringing an electrical charging Vehicle to the vicinity of the support vehicle on the airfield and charging the support vehicle in situ in its working environment or close to its working environment, thereby avoiding the need for the support vehicles to drive as far to recharge and therefore reducing wear.

According to another aspect of the invention there is provided a method of reducing energy used to recharge an airside support vehicle. The method comprises bringing an electrical charging vehicle to the vicinity of the support vehicle on the airfield and charging the support vehicle in situ in its working environment or close to its working environment, thereby avoiding the need for the support vehicles to drive as far to recharge and therefore collectively less energy is used. Driving a single electrical charging vehicle to meet and feed several airside support vehicles uses less energy than driving each airside support vehicle further to a fixed remote charging station

BRIEF DESCRIPTION OF THE DRAWINGS

Figure lA shows a simplified schematic view of an energy storage vehicle in a first configuration; Figure IB shows another simplified schematic vicw of the energy storage vehicle of Figure I Figure 2 shows a simplified schematic view of an energy storage vehicle in a second configuration; Figure 3 shows a simplified schematic view of the energy storage vehicle of Figure 1 in a platoon with a plurality of work vehicles; Figure 4 shows a simplified schematic view of the energy storage vehicle of Figure 2 in a platoon with a plurality of work vehicles; Figure 5 shows a simplified schematic view of a plurality of the energy storage vehicles of Figure 1 in a platoon and charging at a fixed charging point; Figure 6 shows a simplified schematic view of a plurality of the energy storage vehicles of Figure 2 in a platoon and charging at a fixed charging point; Figure 7 shows a simplified schematic view of a plurality of energy storage vehicles having a further configuration and in a platoon and charging at a fixed charging point; Figure 8 shows a simplified schematic view of an energy storage vehicles travelling between a fixed charging point and a platoon of work vehicles; Figure 9 shows a simplified schematic view of an energy storage vehicles travelling between a fixed charging point and a plurality of platoons of work vehicles; Figure 10 shows a simplified schematic view of another configurat on of an energy storage vehicle, whilst charging a plurality of work vehicles; Figure 11 shows another simplified schematic view of another configuration of an energy storage vehicle, whilst charging a plurality of work vehicles; Figure 12 shows a method of charging a vehicle in an operating environment; Figure 13 shows another method of charging a vehicle in an operating environment; Figure 14 shows a simplified schematic view of a self-propelled vehicle in a first configuration; Figure 15 shows a simplified schematic view of a self-propelled vehicle in a second configuration; Figure 16A shows a schematic view from the side of a plurality of the self-propelled vehicles of Figure 14 in a vehicle platoon; Figure 16B shows a schematic view from the side of a plurality of the self-propelled vehicles of Figure 15 in a vehicle platoon; Figure 17A shows a schematic view from the side of a connection formed between a pair of the self-propelled vehicles of the platoon of Figure 16A: Figure 17B shows a schematic view from the side of a connection formed between a pair of the self-propelled vehicles of the platoon of Figure 16B; Figure 17C shows a schematic view from above of a connection formed between a pair of the self-propelled vehicles in a further configuration; Figure 17D shows a simplified three dimensional view of a pair of charging apparatuses for use in the vehicles of the preceding Figures; Figure 18 shows a plurality of the self-propelled vehicles of Figure 14 in a vehicle platoon and charging at a fixed charging point; Figure 19 shows a plurality of the self-propelled vehicles of Figure 15 in a vehicle platoon and charging at a fixed charging point; Figure 20 shows a plurality of the self-propelled vehicles of Figure 15 in a vehicle train and charging at a ground based charging point; Figure 21 shows a simplified schematic view of another self-propelled vehicle; Figure 22 shows a the vehicle of Figure 14 and the vehicle of Figure 21 in a vehicle train; Figure 23 shows a flow diagram for a method of charging a vehicle; Figure 24 shows a flow diagram for a further method of charging vehicles; Figure 25 shows a simplified system diagram for a system comprising a plurality of vehicles and a controller: and Figure 26 shows a simplified, schematic, plan view of an airport comprising a logistics system.

DETAILED DESCRIPTION

The below description describes vehicles, systems and methods for use in an airside environment. It will be appreciated that minor modifications could be made in order for the various features to be applicable in other environments, for example warehouses, docksides, or other logistical environments and scenarios. The vehicles, systems and methods described below may be based on those disclosed in UK Patent Application No. 1821134.2 (published as GB2576800) and International application No. PCT/GB2019/053562 (published as W02020/128442), the entire contents of which are incorporated within this specification by reference.

Figure IA shows an energy storage vehicle 500, specifically an energy storage vehicle for use in an airside environment. The vehicle 500 comprises an energy storage means 503. The energy storage means 503 is a battery and may be a series of batteries. The battery may be a lithium ion battery. The battery is connected to at least one charging apparatus 501 via which electrical power can be supplied to an electric vehicle. In this example a pair of charging apparatuses 501a, 501b are provided. Even more charging apparatuses may be provided on and around the vehicle 500. The pair of charging apparatuses 501a, 501b are provided at opposite ends of the vehicle. The opposite ends are nominally a front and a back of the vehicle 500.

The main function of the energy storage vehicle 500 is to store, transport and deliver energy. The energy storage vehicle may be towed by another vehicle. In a preferred example the energy storage vehicle is self-propelled. A still further preferred example the energy storage vehicle is operable in an autonomous driving mode. Figure 1B shows the energy storage vehicle with further components shown in schematic form. A motor is provided to provide tractive force to at least one set of wheels 504. Multiple motors may be used, for example one per axle or even one per wheel. The motor 502 draws power from the battery 503, in this example the vehicle further comprises a controller 505, for controlling the motor, and sensors 506a, 506b for sensing an environment surrounding the vehicle. The vehicle further comprises a transceiver 508 for sending data relating to the vehicle 500 and for receiving control signals and/or tasks to be executed. The sensing and autonomous operation of the vehicle is analogous to the autonomous dollies described in UK Patent Application No, 1821134.2 and International application No. PCT/GB2019/053562, the contents of which are incorporated here by reference. Figure 1B is shown schematically based on the vehicle of Figure la, the arrangement is equally applicable to other configurations of the vehicle, such as those shown in Figures 2. 10 and 11.

Figure IA and Figure 2 show two different arrangements of the charging apparatuses 501a, 501b of the vehicle. in Figure IA the charging apparatuses are arranged vertically. These are inductive charging apparatuses and when an electrical connection is formed between one of them and an external charging apparatus the electrical connection is formed substantially horizontally. In Figure 2 the charging apparatuses extend substantially horizontally from the vehicle. The first charging apparatus 501a is arranged at a lower height on the vehicle than the second charging apparatus 501b. The charging apparatuses 501a, 501b form electrical connections in a substantially vertical direction with another charging apparatus either on top (in the case of the first charging apparatus 501a) or below (in the case of the second charging apparatus 501b).

Figure 3 shows the energy storage vehicle 500 of Figures IA and I B in a platoon with a plurality of work vehicles 100. Each vehicle is joined end to end, and an electrical connection is formed between adjacent vehicles. The energy storage vehicle stores enough energy to recharge a plurality of vehicles. The electrical connections are formed using inductive charging apparatuses on each vehicle, the connections formed substantially horizontally. The energy storage vehicle 500 is operable to join on to an existing platoon of work vehicles 100. The platoon of work vehicles have assigned tasks (for example transporting baggage or other cargo in the case of airside dollies) and the work vehicles may continue carrying out their tasks when the energy storage vehicle 500 joins the platoon. In this way the work vehicles can be recharged without having to pause or stop their assigned tasks. It also allows the work vehicles to be charged within the operating environment without having to travel to a remote charging location. Figure 4 shows the energy storage vehicle 500 of Figure 2 in a platoon with a plurality of work vehicles 100. The operation of the vehicles and the platoon is the same as in Figure 3. The only difference is that the electrical connections between the vehicles are formed substantially vertically, between horizontally extending charging apparatuses.

Figures 5 to 7 show a plurality of energy storage vehicles 500 charging at a fixed charging point 150. The fixed charging point 150 in another embodiment could be a mobile charging point -for example a mobile hydrocarbon fuel powered electricity generator. As with when an energy storage vehicle 500 charges a plurality of work vehicles 100 only a single connection needs to be made to the energy sourcc. In the case of recharging the work vehicles 100 the energy storage vehicle 500 is the source, in this case the energy storage vehicles 500 require recharging and so a charging station 150 is the source. One energy storage vehicle 500 forms a connection with the charging station 150 and one or more further energy storage vehicles 500 can platoon and electrically; connect with the energy storage vehicle 500 connected to the charging station 150 in order to also be recharged. This allows for fewer charging stations 150 to be provided, as multiple energy storage vehicles 500 can be charged simultaneously from a single point 150. Figures 5 and 6 illustrate the connections formed for the energy storage vehicles of Figures] A and 2 respectively. Figure 7 shows a further configuration of the energy storage vehicle 500, in which a further charging apparatus is provided on an underside of the energy storage vehicles. This further charging apparatus may be configured to only receive a charge. The further charging apparatus forms a substantially vertical electrical connection with a ground based charging station, which may be installed on or within the ground. The further charging apparatus may also be an inductive charger.

Once an energy storage vehicle 500 has received sufficient charge from a charging station 150 it can be controlled to drive to an operating environment in order to deliver the stored energy to work vehicles 100. Figures 8 and 9 provide examples of possible routes and routines that an energy storage vehicle 500 may follow. In Figure 8 the energy storage vehicle 500 is partnered with a single group of work vehicles 100. The energy storage vehicle is charged at the charging station 150 and then drives to join a platoon formed by the work vehicles 100. The energy is delivered to the work vehicles 100 as they continue to operate. The platoon vehicles may be on their way to a part of the airfield to perform their work tasks and individual vehicles may join and leave the platoon whilst the energy storage vehicle is part of the platoon charging one or more of the platoon vehicles. The platoon work vehicles may be configured to pass charge to a particular work vehicle in preference to others (possibly with the charge passing through other work vehicles before it gets to said particular work vehicle).

The particular work vehicle may be selected as the one that has a low level of power in its battery/supercapacitor, or the one that will leave the platoon sooner than others (and so not be in contact for charging later on in the platoon's journey). Alternatively, or additionally instead of prioritising the charging of selected work vehicles in the platoon, a group of the platoon work vehicles may share the additional charge equally, or to a level where they have equal charge. In Figure 9 the energy storage vehicles 500 is tasked with providing energy to a plurality of groups of work vehicles. The energy storage vehicle 500 receives energy from the charging station 150 and then drives to each group of work vehicles 100, delivering charge in turn. Upon reaching each group the energy storage vehicle 500 joins a platoon formed by the work vehicles 100 and delivers the energy as the work vehicles continue to operate. The energy storage vehicle 500 then moves on to the next group and repeats the process. The energy storage vehicle continues to deliver energy to groups of vehicles until it reaches the end of its tasks or its energy stores are depleted. After running out of charge (but keeping a reserve in order to drive itself) the energy storage vehicle returns to the remote charging station 150 to recharge A group of vehicles can of course comprise just a single vehicle. There is no intent to exclude charging just one vehicle.

Figure 10 shows another configuration of the energy storage vehicle in which it is operating with the work vehicles in a 'sow and piglet' mode. Multiple work vehicles are able to charge directly at the energy storage vehicle simultaneously. The energy storage vehicle comprises a plurality of charging points. In this example each side has at least one charging point, allowing at least one work vehicle to charge at each side.

The front and back of the energy storage vehicle each have a single charger, and a work vehicle can therefore charge end to end with the energy storage vehicle. The work vehicles can also charge at the sides of the energy storage vehicle, driving end on to charge at the charging points. In this configuration the energy storage vehicle comprises a pair of charging points on each of the left and right side, allowing a pair of work vehicles to charge on each side.

It is possible in some embodiments to have work vehicles in a chain linked to the energy storage vehicle -for example there are 6 work vehicles being charge in figure 10. and a seventh can couple to the free/ available charging/recharging formations at the ends or sides of the work vehicles shown, and be charged via the intermediate work vehicle. Of course, up to 6 more work vehicles can chain onto the available ends of the 6 work vehicles shown, and more at the sides -if there were charging/discharging formations at the sides of the work vehicles. A chain of work vehicles being charged could be longer than two chargingly coupled work vehicles.

Another configuration for charging in a 'sow and piglet' mode is shown in Figure 11. In this example the work vehicles also have charging points on the side, and can therefore park parallel with the energy storage vehicle to be charged.

Example steps for methods of charging the work vehicles 100 are shown in Figures 13 and 14. An energy storage vehicle, preferably the energy storage vehicles 500 as described above, is provided in a first step 410. Energy is then provided 420 to the energy storage vehicle. Whilst providing energy preferably constitutes charging an onboard battery 503 (or possibly a supercapacitor) of the energy storage vehicle 500, it is also envisaged that the energy storage vehicle may comprise a genset (generator set), in which case providing energy may take the form of pumping fuel into a fuel tank of the energy storage vehicle. The energy storage vehicle is controlled to deliver energy to work vehicles 100. in Figure 12 the energy storage vehicle is simply piloted 430 (either autonomously or by a human driver) to an operating environment in which the work vehicles are operating. In Figure 13 the energy storage vehicle is only dispatched if a communication is received 425, the communication comprising an energy request for one or more work vehicles 100. Once the energy storage vehicle is within the operating environment it electrically couple with one or more of the work vehicles 100 within that environment and provides 400 energy to said one or more work vehicles.

Figure 14 shows an airside support vehicle, specifically an airside dolly, which is an example of a work vehicle 100 configured to be charged by the energy storage vehicle 500. Further details on such an airside support vehicle can be found in UK Patent Application No. 1821134.2 with regards to a cargo and baggage dollies. The vehicle comprises a pair of charging apparatuses 101a, 101b. A first charging apparatus 101a is positioned at a first end of the dolly and a second charging apparatus 101b is positioned at a second end of the dolly. The first and seconds ends may refer to a front and back of the dolly respectively; although, as the dolly is preferably configured to be equally capable of driving in either direction, the terms front and back are not necessarily accurate but are provided for spatial reference. The vehicle 100 comprises an energy storage means 103. The energy storage means in this example takes the form of a battery, such as a lithium ion battery. Power is provided from the battery to drive at least one motor 102. The motor 102 provides tractive force to at least one set of wheels 104. In this example there is provided a single motor 102 to drive a front axle of the vehicle. In other examples a pair of motors may be provided, one to drive a front axle and another to drive a rear axle in other examples each wheel 104 may be driven by its own motor.

The charging apparatuses 101a, 101b are inductive charging apparatuses, analogous to the charging apparatuses 501 of the energy storage vehicle 500. The charging apparatuses are mounted in a substantially vertical plane. Mounting the inductive charging apparatus in a vertical orientation can limit damage and possible contamination to the apparatuses that may be caused than if the charging apparatus was mounted beneath the vehicle.

In this example the vehicle 100 comprises a controller 105. The controller is configured to provide control to the motor 102. The controller receives data regarding the vehicle's environment from one or more sensors 106a, 106b. The sensors comprise distance sensors. The distances sensors 106a, 106b may comprise one or more of, radar, stereo camera, ultrasonic and lidar sensors.

Figure 15 shows another configuration of a dolly. In this configuration the charging apparatus 101a, 101b are orientated in a horizontal position and extend longitudinally away from a main body of the dolly. One of the charging apparatuses is positioned at higher point than the other charging apparatus.

In either the configuration of Figure 14 or Figure 15, when multiple dollies are arranged end to end they can share electrical energy between themselves via the respective charging apparatuses. This is illustrated schematically in Figures 16A and 16B for the vehicles of Figures 14 and 15 respectively. In Figure 16A a first vehicle 100a, having charging apparatuses 101a and 101b serves as a lead vehicle. A second vehicle 100b is electrically coupled to the first vehicle 100a to form a platoon. The second vehicle has charging apparatuses 101c and 10Id. The front charging apparatus 101c of the second vehicle 100b forms an electrical connection with the rear charging apparatus 101b of the first vehicle 100a. A third vehicle 100c is electrically coupled to the second vehicle 100b to continue the platoon. The third vehicle has charging apparatuses 101e and 101f. The front charging apparatus 101e of the third vehicle 100c forms an electrical connection with the rear charging apparatus 101d of the second vehicle 100b. The platoon created by the electrical connection of vehicles could contain many more vehicles than just the three illustrated. The connections between more vehicles in a platoon and would follow the same connection sequence as described above. The charging apparatuses are vertically mounting inductive chargers. The first charging apparatus 10Ia is configured to provide charge and the second charging apparatus 10 lb is configured to receive charge. In other examples each charging apparatus 101a, 101b is configured to both deliver and receive charge.

The platoon shown in Figure 316B is largely identical to that shown in Figure 16A, with the difference being that the charging apparatuses are orientated substantially horizontally. Each vehicle has one charging apparatus situated higher than the other charging apparatus, such that vehicles can tessellate, with charging apparatuses of adjacent vehicles situated one on top of the other.

The connection is made substantially horizontally between the substantially vertically mounted chargers in the configuration of Figure 16A and substantially vertically between the substantially horizontally mounted chargers in the configuration of Figure 16B.

Figures 17A, 17B and 17C show thc connections made between inductive plates 120 of the charging apparatuses 101b, 10Ic in further detail. Each charging apparatus 101b, 101 c comprises an inductive charging plate 120. When the vehicles are arranged in a platoon, the inductive charging plates 120 overlap with each other, allowing an electromagnetic field to be formed between the plates 120. In the configuration of Figure 16A the plates 120 overlap such that are substantially symmetrical about a substantially vertically and laterally extending plane, as show in Figure 17A. In the configuration of Figure 16B the plates 120 overlap such that are substantially symmetrical about a substantially horizontally and laterally plane, as show in Figure 17B. Another configuration is shown in Figure 17C; this view is taken from a bird's eye perspective, so viewing the connection from above. Each charging apparatus extends longitudinally, with the inductive plates 120 orientated in a vertically and longitudinally extending plane such that a connection is formed substantially laterally. An example arrangement of the charging apparatuses and the plates 120 is shown (without the vehicles for clarity) in Figure I7D. The plates 120 are arranged opposite each other and an electromagnetic field is formed between them, permitting a charge to pass perpendicularly to a plane of the plates. A full overlap is not required. The better the overlap the stronger the connection and so the vehicles are controlled to target keeping the plates 120 overlapping as much as possible.

The vehicles are maintained at a predetermined distance from each other. The distance is dose enough such that a reliable electrical connection can be formed, with the induction plates 120 overlapping. The distance is also kept far enough so that the risk of collisions is kept low in the event of an emergency braking event. The vehicles use a front sensor 106a to determine distance to a preceding vehicle and the controller 105 maintains a suitable distance accordingly. The vehicles are preferably operable in at least a Level 1 autonomous mode (as defined by the SAE's autonomy levels) and are therefore capable of following another vehicle at a set distance. For level 1 vehicles a driver may provide the steering input, whilst in Level 2 and above vehicles a controller is operable to provide steering input to maintain or follow a path. The path may be set by the first vehicle, a driver of the first vehicle, or a remote controller -either human or computer.

There is preferably no mechanical connection made between the vehicles. This allows for platoons to be easily formed between vehicles without the requirement for physical coupling. This removes the requirement for manual coupling by a driver, or relatively complex automated mechanical coupling systems.

In another version, the charge transfer between vehicles is not via inductive charging but via physical electrode contact and current flow.

Multiple vehicles in a platoon can share energy amongst themselves to have those vehicles having batteries with a higher state of charge support those vehicles having batteries with a lower state of charge. This allows vehicles to stay out longer as a group before returning to charge over vehicles that are only configured to charge at static charging points. As batteries near their end-of-life they degrade and are unable to hold as much charge. These older batteries can be supported by vehicles with newer batteries in the working environment, increasing the working life of vehicles and their batteries. This increases the value for money of each vehicle and delays any further investment required in buying new vehicles or batteries Vehicles that are located a long distance from a power outlet location can be donated energy from a vehicle also working within the work environment (or otherwise able to travel to be in proximity to the vehicle requiring power). The vehicles can therefore redistribute energy reserves amongst themselves potentially extending shift length and reducing the number of require recharging events. In an example scenario a plurality of vehicles could be operating at a location remote from a charging point. If one of the vehicles reaches a low power mode then it could be forced to go and recharge, potentially putting it out of action for the remainder of the shift. Causes of low power could range from having had to have performed extensive manoeuvres, been responsible for carrying greater loads, or having a more aged battery. If another dolly (vehicle) has a higher state of charge it can share this energy store with the more depleted or nearly depleted dolly (vehicle). This could take the form of both vehicles temporarily being placed out of action during the re-charge or, preferably, the vehicles forming a temporary train and continuing their tasks in tandem whilst the charged vehicle charges the depleted vehicle. In this way all of the vehicles can reach the end of the shift without having to recharge and then returning to a charging location only at the end of the shift.

When the vehicles are in a platoon, and in electrical communication, only one of the vehicles of the platoon needs to dock at a charging location 150 in order for all of the vehicles to be charged. This is illustrated in Figures 18 to 20. One fixed charging point 150 can therefore be used to recharge multiple vehicles when they are parked end-to-end. This allows for fewer charging points to be installed over each vehicle having to charge separately, reducing the disruption and financial overheads of installing new infrastructure. The first vehicle may receive its charge from the fixed charging point 150 from its usual charge receiving apparatus and a reciprocal charging apparatus 151 on the fixed charging point, as in Figures 18 and 19. In other examples a different charge receiving apparatus 107 may be used. This may be an inductive charging unit 107 placed on the bottom of the vehicles as shown in Figure 20, it could also be a plug-in connection or any other suitable charging means.

Another example of an airs dc vehicle 200 is shown in Figure 21. In this example the vehicle 200 is a set of self-propelled stairs for embarking and disembarking passengers from vehicles. Various other vehicles, both from airside support and other logistical environments are also applicable here. Unlike the vehicles 100 of Figures 14 and 15 this vehicle has only a single charging apparatus 201. The vehicle also does not comprise an energy storage means for storing energy to supply the traction motor 202. The omission of these components makes for a simplified vehicle, having lower cost and lower maintenance requirements. This simplicity comes at the cost of the vehicle being able to store its own power. The way this vehicle 200 operates is to receive power from another vehicle 100 that does comprise an energy storage means 103, as shown in Figure 22. The stairs 200 can therefore just be provided power when they need to move. The motive requirements for stairs and some other logistical equipment types is fairly low in comparison to other vehicles, such as baggage dollies, and so those components that would be normally needed to drive the motor (predominantly a battery) can be removed. The stairs 200 may well have other storage means, not related to driving the traction motor 202. For example a smaller battery may be provided for providing lighting or other auxiliary functions. Other storage means, such as hydraulics or flywheels may also be used to provide short term energy storage.

Example methods of controlling and charging, or otherwise sharing power between vehicles, are illustrated in Figure 23 and 24.

In Figure 23 a pair of vehicles are provided, each having a charging means provided on it 201, 201. The two vehicles are bought into proximity to one another 203. This may be done by bringing the first vehicle proximal to the second vehicle, or vice versa, or bringing both vehicles to another location. Bringing the vehicles together is carried out autonomously, in some examples one or more human drivers may be used.

Once the vehicles are in proximity to each other the charging means are aligned and energy can be shared between the vehicles 204. In order that the vehicles can continue to operate at least one of the vehicles is controlled to carry out its tasks 205. The other vehicle is configured to follow the controlled vehicle and, where possible, also complete its own tasks, whilst remaining electrically coupled to the controlled vehicle.

In Figure 24 a third vehicle is also introduced. First charging means are provided on the first vehicle 301, second and third charging means are provided on the second vehicle 302, and fourth charging means are provided on the third vehicle 303. Each vehicle may have further charging means provided on them. Preferably each vehicle is constructed almost identically, at least in so far as the charging/energy sharing elements are concerned, with each vehicle provided with a pair of charging means. At least one charging means of each vehicle is configured to receive an electrical charge and at least one charging means is configure to send an electrical charge. The charging means for receiving an electrical charge and the charging means for sending an electric& charge may be one and the same. The vehicles may have more than one structure that is capable of both charging the vehicle and discharging power to another vehicle. The first vehicle and third vehicles are brought in to proximity to the second vehicle 304, 305. The first vehicle is positioned at a front of a platoon formed of the first, second and third vehicles. The third vehicle is positioned at the end of the platoon. The second vehicle is positioned in the middle of the platoon, between the first and second vehicles. Once in position in a platoon, with the charging apparatuses aligned, energy is shared between the vehicles 306. In order that the vehicles can continue to operate, at least one of the vehicles is controlled to carry out its tasks 307. The other vehicles are configured to follow the controlled vehicle and, where possible, also complete their own tasks, whilst remaining electrically coupled to the other vehicles within the platoon. More vehicles can be added to the platoon using the same methods as above, If the platoon vehicles are provided with appropriately positioned charging apparatus at their sides, additional vehicles can join the platoon and share charge as they sit/run alongside the platoon.

A system comprising a plurality of the vehicles 100 is shown in Figure 25. Further details on such a system can be found in UK Patent Application No. 1821134.2 with regards to a baggage handling system at an airport. This system also comprises some stairs 200 as described with reference to Figures 21 and 22 but not all systems would comprise this extra vehicle. A central controller 160 is provided and configured to communicate at least some of the vehicles 100. The central controller 160 may instead be a distributed controller, with processing shared between one or more of the vehicles. The central controller may be one of the controllers of the vehicles, given a higher rank in a controller command hierarchy. Each vehicle 100a, 100b, 100c, comprises a transceiver 108. The transceivers 108 are configured to send data regarding the vehicles, such as a state of charge of the vehicles' respective batteries 103. The controller is connected to its own transceiver 168. The controller is configured to receive vehicle data via the transceiver. The controller is also configured to issue commands via the transceiver 168.

The batteries are shown illustratively in Figure 25 to show a current state of charge of each of the vehicles. Vehicle 100a has a medium state of charge, vehicle 100b has a very low state of charge, and vehicle 100c has a relatively high state of charge. As vehicle 100c has a relatively high state of charge it is commanded to partner with and form a charging platoon with vehicle 100b. In this way both vehicles can continue to operate and share energy. One or both vehicles may be re-tasked so that their individual tasks are aligned. Other vehicles may therefore be reassigned in order to more efficiently distribute tasks. Vehicle 100a's state of charge is sufficient that it is able to provide power to the stairs 200, and so it is tasked to provide power accordingly. The stairs also comprise a transceiver 208 and a controller 205. The controller may be less complex than that of the other vehicles 100 and may not be required to carry out any path planning. Instead, the transceiver may receive instructions from one or more of the central controller 160 and the vehicle controller 108 and be configured to follow the vehicle 100a. In this way the vehicle 100a can perform the role of a tug, without having to actually physically couple to the stairs 200. Power and a trajectory are provided by the vehicle 100a and the stairs simply follow, maintaining a suitable distance to receive power to drive the traction motor 202.

The central controller 160 is operable schedule and set tasks for each of the vehicles. The tasks that may be set are dependent upon the data received from the vehicles. In particular the vehicle's current location data and state of charge are used to assign tasks. For example, the controller will assign tasks based on the urgency of the task but also dependent upon which vehicles are closest and therefore more readily available to complete the task. The state of charge is taken into account as some tasks may require more energy to complete, for example carrying heavier loads or travelling longer distances. in this case the controller may assign vehicles with a higher state of charge, or put vehicles into platoons so that power can be shared between the vehicles.

Figure 26 provides an example of a logistics system comprising energy storage vehicles 500 and work vehicles 100 such as those described above. The logistics system is used within an airport, and operates within an airport perimeter 700. A plurality of charging stations 150 are provided for the provision of energy to at least the energy storage vehicles. The charging stations 150 are positioned at the perimeter 700 of the airport in this example, but they could also be located elsewhere, such as at a terminal 710 or vehicle depot. in this example airport there are a pair of terminals 710, of course some airports may have only a single terminal and others may have many more. Groups of work vehicles 100 operate in various work zones around the airport. Some of these work zones are proximal to the terminals, and may comprise baggage handling areas, areas for the embarkation and disembarkation of passengers and other terminal related work zones. Some work zones may be further from the terminals, such as areas for servicing or cleaning aircraft. Airports can span several kilometres and so the distances between work zones, terminals, charging stations and other points on the airport can be relatively large. Considering a lot of airside work vehicles have low speed limits, a large amount of time can be wasted moving from one location to another in a conventional airport. Providing the energy storage vehicles 500 to remove the requirement of the work vehicles to travel to refuel or recharge help to remove this wasted time. A controller is provided that is in communication with each work vehicle 100 and each energy storage vehicle 500. Some airports may have multiple controllers, each controller being assigned certain work vehicles and energy storage vehicles and an area in which the controller 160 is in control. For example, each terminal and an associated area may have its own controller 160, set of energy storage vehicles 500 an set of work vehicles 100. The controller may also be located on one or more of the vehicles 100, 500_ or be distributed amongst several locations or vehicles. The controller 160 allocates tasks to both the work vehicles 100 and the energy storage vehicles 500. The energy storage vehicles are tasked with retrieving energy from at least one of the charging stations 150 and delivering it to the groups of work vehicles 100. The controller 160 assigns tasks based on the energy storage vehicles' 500 respective proximities to charging stations 150 and groups of work vehicles. As can be seen in this example, the bottom energy storage vehicle 500 has been assigned two groups of work vehicles 100 to recharge, and so shuttles between the groups of work vehicles 100 and the charging station. In following a group of work vehicles 100 to recharge them an energy storage vehicle may become closer to a different charging station 150 than the one it started from. The controller can take this new distance into account and task the energy storage vehicle 500 to charge at the closer charging station 150. The controller 160 uses an algorithm to control both the work vehicles and the energy storage vehicles to complete all required tasks whilst attempting to minimised the distance covered and time spent in completing the tasks, in order to improve efficiency over conventional systems. Methods of control and associated systems that may be used in such a system are described in UK Patent Application No. 1821134.2 and International application No. PCT/GB2019/053562, the contents of which are incorporated here by reference.

In some ways the energy storage vehicle discussed herein can be considered a special work vehicle whose job it is to fuel/charge up other work vehicles. Discussion relating to work vehicle to work vehicle energy sharing may also apply to energy storage vehicle to work vehicle energy sharing.

The energy storage and work vehicles are normally land based vehicles that are driven on the ground.

Each concept discussed in the present disclosure, except where otherwise provided, may be utilised independently or in combination with any other concept discussed. The skilled person win understand that the specific examples discussed are simply embodiments of the discussed concepts for illustrative purposes and that combinations disclosed in relation to one specific example are not intended to limit the different combinations that could be provided without departing from the scope of the

disclosure.

The terms power sharing, charging and energy sharing are used interchangeably unless stated specifically otherwise.

The examples given above with relations to the various vehicle types are equally applicable to other vehicle types, both airside and otherwise. Where an aspect of the disclosure is discussed in relation to an airside vehicle or dolly, unless otherwise necessary any feature of the described vehicle may be provided as part of a vehicle, such as a land vehicle, water vehicle, air vehicle, or road vehicle.

Claims

CLAIMS1. A method of providing electrical power to a battery powered self-propelled vehicle in an operating environment, the method comprising: providing an electrical energy storage vehicle; providing electrical energy to the energy storage vehicle at a remote energy provision point; driving the electrical energy storage vehicle to an operating environment; and providing electrical energy to an electric work vehicle operating in the operating environment using the electrical energy storage vehicle.
2. A method according to claim 1, the method further comprising receiving a communication comprising an energy request for a work vehicle in the operating environment.
3. A method according to claim 2, the method further comprising assessing an energy level of the work vehicle and generating the energy request in dependence on the charge state of the work vehicle.
4. A method according to any preceding claim wherein providing energy to the work vehicle comprises bringing the work vehicle and the energy storage vehicle together and forming an electrical power transfer connection between the energy storage vehicle and the work vehicle in order to charge the work vehicle.
A method according to claim 4 wherein the electrical connection is formed using inductive charging.
6. A method according to any preceding claim wherein the energy storage vehicle is driven autonomously.
7. A method according to any preceding claim wherein the work vehicle is driven autonomously.
8. A method according to any preceding claim wherein providing energy to the energy storage vehicle comprises charging a battery or supercapacitor of the energy storage vehicle
9. A method according to any preceding claim wherein the method comprises the electrical energy storage vehicle providing energy to multiple work vehicles in the operational environment.
10. A method according to any preceding claim wherein charging the work vehicle takes place whilst the work vehicle is moving and/or whilst it is performing its
11. A method according to any preceding claim wherein the method comprises bringing the work vehicle and the energy storage vehicle side to side in order to charge the work vehicle.
12 A method according to any preceding claim wherein the operating environment is a work zone within an airside environment, and optionally wherein the remote energy provision point is located within the airsidc environment but outside of the operating environment.
13. A method according to any preceding claim, the method further comprising planning a route and/or a schedule for the energy storage vehicle to charge a plurality of work vehicles
14. A method according to any preceding claim wherein the work vehicle is an airside luggage or cargo transport vehicle such as a luggage or cargo dolly.
15. A method according to any of claims 1 to 13 wherein the work vehicle is from the group:-Movable aircraft stairs Catering vehicle Honey truck (aircraft human effluent disposal vehicle) Hydrocarbon fuel bowser Passenger or aircrew or ground crew transport Luggage or cargo handling conveyor belt Scissor lift De-icer Push back tug.Aircraft escort vehicle, e.g. adapted to show aircraft a selected runway exit path
16. A method of reducing inefficiencies in a logistical system comprising a plurality of vehicles, the method comprising: providing an energy storage vehicle; providing energy to the energy storage vehicle at a remote energy provision point; driving the energy storage vehicle to an operating environment; and providing energy to a work vehicle operating in the operating environment using the energy storage vehicle.
17. An energy storage vehicle for use in the method of any preceding claim, the vehicle comprising: a motor for providing propulsion for the energy storage vehicle; an energy storage means; a first charging apparatus for receiving electrical power from a static charging point; and a second charging apparatus for providing electrical power to further vehicles.
18. A vehicle according to claim 17 wherein the second charging apparatus comprises a plurality of charging apparatuses.
19. A vehicle according to claim 17 or claim 18 wherein at least one and preferably all of the charging apparatuses are an inductive charging apparatus.
20. A vehicle according to claim 19 wherein the, or each, inductive charging apparatus is mounted in a vertical plane.
21. A vehicle according to any one of claims 17 to 20 wherein the energy storage vehicle has at least four sides and wherein each side has a charging apparatus located upon it.
22. A logistics system comprising a plurality of work vehicles, configured to receive energy from an energy storage vehicle; an energy storage vehicle configured to provide energy to one or more of the plurality of work vehicles; a computer device, configured to issue commands to the energy storage vehicle and the plurality of work vehicles; wherein the plurality of work vehicles, the energy storage vehicle and the computer device are in communication and wherein the computer device is configured to assign tasks to the energy storage vehicle to recharge the work vehicles.
23. A logistics system according to claim 22 wherein the system comprises a plurality of energy storage vehicles and each energy storage vehicle is assigned to a group of work vehicles.
24. A logistics system according to claim 22 or claim 23, wherein the vehicles are located within an a rside environment.
25. A logistics system according to any one of claims 22 to 24 wherein the energy storage vehicles and the plurality of work vehicles are autonomous vehicles.
26 A method of increasing the useful operational time of electrical airside support vehicles on an airfield comprising bringing an electrical charging vehicle to the vicinity of the support vehicle on the airfield and charging the support vehicle in situ in its working environment or close to its working environment, thereby avoiding the need for the support vehicle to spend downtime travelling to a fixed recharging point further away.
27. The method of claim 26 comprising charging a plurality of electrical charging vehicles at a charging station, and moving the plurality of charged electrical charging vehicles to a plurality of different temporary locations on an airfield, and bringing a plurality of support vehicles to the charging vehicles and charging the support vehicles using the charging vehicles, at least one charging vehicle, and optionally a plurality of them, having a cluster of support vehicles in charging communication with themselves so as to have a single charging vehicle charging more than one support vehicle simultaneously.
28. The method of claim 26 or of claim 27 comprising at least the work vehicles and optionally the charging vehicles, being computer controlled and the computer determining the location of the support vehicles and using that to determine which support vehicles will move where to meet which charging vehicle, dependent upon the position of the support vehicles, the charge they need, and the charge available in the particular charging vehicle to which they are sent by the computer, and after determining which support vehicle will go where, controlling the support vehicles to move to the determined location applicable to them
29. The method of claim 28 wherein the charging vehicles are computer controlled and the computer automatically determines a respective charging location where it is advantageous to send each charging vehicle and automatically moves the charging vehicles to their determined respective charging locations and automatically moves the support vehicles to their determined charging locations and causes the automatic charging of the support vehicles.