GB2630070A

GB2630070A - An automatic electric vehicle charging system and associated method

Info

Publication number: GB2630070A
Application number: GB2307268.9A
Authority: GB
Inventors: Budimir-Bekan Pero
Original assignee: PERO BUDIMIR BEKAN
Current assignee: PERO BUDIMIR BEKAN
Priority date: 2023-05-16
Filing date: 2023-05-16
Publication date: 2024-11-20
Also published as: GB202307268D0

Abstract

An automatic electric vehicle charging system 10 comprises an electric vehicle (EV) 12, an autonomous charging robot 14 and a base station 16. The EV has a charging plug 20 that depends from an undercarriage 22 of the EV. The autonomous charging robot has: a mobile chassis; a spoolable charging cable 18 at least partly within the mobile chassis; and a charging socket onboard the mobile chassis that is coupled with the charging cable. The charging socket is configured, in-use, to receive the charging plug 20 of the EV. The base station has a power supply which is connected to the charging cable of the autonomous charging robot. The autonomous charging robot has a pathfinding controller for autonomously controlling movement of the charging robot between the base station and the EV. The charging socket of the charging robot is reconfigurable between: an open condition, in which the charging socket is opened to receive the charging plug; and a closed condition, in which the charging socket is engaged with the coupled charging plug. The EV may include a motorised EV spool 26 to retract a charging cable 24 within the EV, the retractable charging cable being coupled to the charging plug.

Description

AN AUTOMATIC ELECTRIC VEHICLE CHARGING SYSTEM AND ASSOCIATED METHOD

The present invention relates to an automatic electric vehicle charging system and method, and particularly but not exclusively to the automated charging of an electric vehicle in public and residential settings.

The invention also relates to the use of an autonomous charging robot for use in automatic electric vehicle charging systems and methods.

With the number of electric vehicles on the road increasing, so too is the demand for electric vehicle charging points. Electric vehicle charging points can be installed at home for individual use, and in public parking locations for public use.

Three key aspects that should be considered when designing electric vehicle charging points include safety, speed of charging and accessibility. A user should not experience an electric shock in the event of an electrical malfunction, nor should an electrical fault cause a fire. Additionally, users often want their car to be charged in a short a period as possible, often resulting in heavy, thick cables that can be cumbersome.

Current charging solutions involve the user having to exit their car, unwind heavy charging cables to make the connections, exposing themselves to high voltage terminals. This connection process is particularly taxing in the event of adverse weather conditions and in instances where users are managing a disability. This can also lead to the user not returning charging points to their stored conditions, leaving cables in the path of passers-by, and thus creating trip hazards.

It is an object of the present invention to reduce or substantially obviate the aforementioned problems.

According to a first aspect of the invention, there is provided an automatic electric vehicle charging system comprising: an electric vehicle having an undercarriage and a charging plug which depends from the undercarriage during an in-use charging state of the electric vehicle; and an autonomous charging robot having a mobile chassis, a spoolable charging cable which is at least partly within the mobile chassis, and a charging socket onboard the mobile chassis and coupled with the charging cable, the charging socket being configured to in-use receive the charging plug of the electric vehicle; and a base station having a power supply which is connected to the charging cable of the autonomous charging robot; the autonomous charging robot further comprising a pathfinding controller for autonomously controlling a movement of the autonomous charging robot between the base station and the electric vehicle.

The automatic electric vehicle charging system provides a fully automated way of charging an electric vehicle, minimising required user input for easy operation by untrained users and negates the need for a user to exit the vehicle, particularly important for those users managing a disability. The autonomous nature of the connection process also minimises time wasted.

Preferably, the charging socket may be reconfigurable between an open condition, in which the charging socket is opened to receive the counterpart charging plug, and a closed condition in which the charging socket is engagable with the coupled counterpart charging plug. Such a reconfigurable charging socket can ensure a secure electrical engagement with the electric vehicle for safe connections in high voltage/high power supply scenarios for fast charging.

Beneficially, the charging socket may include a safety switch, the safety switch being closed when the charging socket is in the closed condition. Safety switches can provide fail safes, interrupting power supply in instances of malfunction, and particularly in instances of electrical malfunction.

The open and closed conditions of the charging socket may be realised by the charging socket comprising a first socket portion and a second socket portion, the first socket portion being moveably connected to the second socket portion, wherein the open condition and the closed condition can at least be in part achieved by movement between the first and second socket portions. Such an arrangement can afford a motion akin to jaws, opening closing for mechanically engaging and disengaging the charging plug that is received therein.

In the instance where the first and second socket portions are provided, the safety swich may include a first contact mounted on the first socket portion and a second contact mounted on the second socket portion. Such safety switches can provide mechanical fail safes, interrupting power supply in instances of malfunction.

Optionally, the autonomous charging robot comprises a housing to at least in part cover the mobile chassis. It is envisaged that the autonomous charging robot may predominantly operate outdoors and so a housing to protect internal componentry from the elements is beneficial.

Advantageously, the housing may be a spherical cap shape. The spherical cap shape acts to minimise any lateral reaction force and maximise a vertical reaction force in the event of the electric vehicle or another vehicle running over the autonomous charging robot.

Additionally, or alternatively, the housing may include a planar road-facing portion. In the event of the or a vehicle running over the autonomous charging vehicle, such a planar road-facing portion can improve engagement with a surface of the parking space for evenly distributing contact pressure.

The housing may include an access opening to in-use receive the charging plug of the electric vehicle therethrough. The inclusion of the access opening can realise improved coverage of the housing over the mobile chassis. The access opening may preferably include a retractable cover which can help protect internal componentry from adverse weather.

Optionally, the mobile chassis may include a driving wheel and first and second support wheels. A single driving wheel can be beneficial for a simpler and more precise drive mechanism, realising the mobile nature of the chassis.

Beneficially, the driving wheel and first and second support wheels may each include a depression element to allow each said wheel to be depressed into the mobile chassis upon the application of an in-use downward force that exceeds a force threshold.

Depression of the wheel in the instance of being run over by the electric vehicle or another vehicle, can engage the autonomous charging robot with a floor of the parking space to prevent damage thereto. The depression elements act to immobilise the autonomous charging robot, reducing the potential risk caused to passers-by if accidently stepped on or driven on.

Preferably, the charging plug is retractable with respect to the undercarriage of the electric vehicle. Retracting the charging plug within the electric vehicle whilst the vehicle is in transit can prevent or limit damage to the charging plug.

The retractable nature of the charging plug may be realised by inclusion of an electric-vehicle spool. Optionally, the electric-vehicle spool is motorised to spool a retractable charging cable within the electric vehicle, the retractable charging cable being coupled to the charging plug.

Advantageously, the charging plug has an infinite order of rotational symmetry in a rotation axis that is or substantially is orthogonal to the undercarriage of the electric vehicle. This allows the autonomous charging robot to receive the charging plug from any approach direction and irrespective of how the user may park the vehicle for charging. In this instance, the charging plug may comprise at least one circular contact, and the charging socket includes at least one complementary contact.

Optionally, the autonomous charging robot includes a receiver, the receiver being in data communication with the pathfinding controller. This arrangement may aid the autonomous charging robot to locate the charging plug.

In some cases, the base station includes a base-station spool for spooling the charging cable within the base unit. As such, the cable can be spooled and stored in the base station and/or the autonomous charging robot, reducing how much charging cable is exposed which may create a tripping hazard. Additionally, minimising how much of the charging cable interacts with the floor of the parking space can minimise friction for reduced resistance to motion of the autonomous charging vehicle.

The base station may preferably include a temperature sensitive power cut-off and/or an electrical sensitive power cut-off. In the event of overheating, a power surge and/or electrical fault, the base station can cut off the power supply.

Optionally, the charging cable may include a low voltage conductor and a high voltage conductor, the low voltage conductor being connected to the autonomous charging robot for supplying power to the mobile chassis and the high voltage conductor being coupled to the charging socket. Separate high voltage and low voltage conductors, which may be considered sub-cables of the charging cable, can minimise the exposure of a high voltage electrical supply to the autonomous charging robot to that only during periods of active charging of the electrical vehicle.

According to a second aspect of the invention, there is provided an automatic electric vehicle charging method comprising the steps of: a] providing an automatic electric vehicle charging system according to the first aspect of the invention; b] moving the autonomous charging robot, using the pathfinding controller, from the base station to the charging plug of the electric vehicle and spooling the charging cable thereof; c] receiving the charging plug by the charging socket; and d] charging the electric vehicle by the power supply.

Optionally, the automatic electric vehicle charging method may comprise a step prior to step c] of, opening the charging socket of the autonomous charging robot, and wherein during step c] include closing the charging socket of the autonomous charging robot around the received said charging plug.

In some instances, the automatic electric vehicle charging method may comprise a step after step a] and before step b] of, instructing the autonomous charging robot to charge the electric vehicle. Inclusion of such a step can help provide control over the automated process.

Beneficially, after step d], the automatic electric vehicle charging method of moving the autonomous charging robot away from the electric vehicle and towards a docked position near the base station. Returning the autonomous charging robot back to the docked position can keep the parking spaces clear of cables and place the robots in positions that a passer-by may expect to find them when in a stand-by condition.

According to a third aspect of the invention, there is provided an autonomous charging robot for autonomously locating and charging an electric vehicle, the autonomous charging robot comprising: a mobile chassis; a spoolable charging cable which is at least partly within the chassis; and a charging socket onboard the chassis and coupled with the charging cable, the charging socket being configured to in-use receive a counterpart charging plug of an electric vehicle which depends from the undercarriage thereof; wherein the charging socket is reconfigurable between an open condition, in which the charging socket is opened to receive the counterpart charging plug, and a closed condition in which the charging socket is engaged with the coupled counterpart charging plug.

For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made by way of example only to the accompanying drawings, in which: Figure 1 shows a first embodiment of an automatic electric vehicle charging system in accordance with the first aspect of the invention, whereby an autonomous charging robot is located near a base station and a charging plug depends from an electric vehicle; Figure 2 shows the automatic electric vehicle charging system shown in Figure 1, whereby a charging socket of the autonomous charging robot receives the charging plug of the electric vehicle; Figure 3 shows the automatic electric vehicle charging system as first shown in Figure 1, whereby the electric vehicle has finished charging and the autonomous charging robot returns to the location near the base station; Figure 4 shows a top plan view of an embodiment of an autonomous charging robot Figure 5 shows a cross-sectional plan view of the autonomous charging robot first shown in Figure 4 with a charging socket in an open condition and a spoolable charging cable connecting the charging socket to the base station; Figure 6 shows a side view of the autonomous charging robot shown in Figure 4; Figure 7 shows a side view of the autonomous charging robot first shown in Figure 4 in a depressed condition whereby a car wheel drives over the autonomous charging robot; Figure 8 shows the charging socket in a closed condition and thus a safety switch also in a closed condition; Figure 9 shows the charging socket in an open condition and thus the safety switch also in an open condition; Figure 10 shows a cross-sectional side view of the electric vehicle; Figure 11 shows a cross-sectional front view of the electric vehicle; Figure 12a shows a side view of the charging plug that depends from the electric vehicle; Figure 12b shows a cross-sectional side view of the charging plug; Figure 12c shows a cross-sectional top view of the charging plug; Figure 13 shows an autonomous charging robot, a docking housing, and a base station of a second embodiment of an automatic electric vehicle charging system in accordance with the first aspect of the invention, whereby in a stand-by condition, the autonomous charging robot is housed within the docking housing; and Figure 14 shows a third embodiment of an automatic electric vehicle charging system in accordance with the first aspect of the invention, having a plurality of autonomous charging robots.

Referring firstly to Figure 1, there is shown an automatic electric vehicle charging system, shown globally at 10, comprising an electric vehicle 12, an autonomous charging robot 14 and a base station 16. This arrangement may be well suited towards charging autonomous or driverless self-driving electric vehicles 12, since charging can happen automatically. The base station 16, which may be referred to as a control panel, has a power supply which is connected to a charging cable 18 of the autonomous charging robot 14.

Connected to an electric vehicle car battery and included in the electric vehicle 12 is a charging plug 20. In-use, the charging plug 20 depends from an undercarriage 22 of the electric vehicle 12, and more specifically, the charging plug 20 is lowered to depend from the undercarriage 22 of the electric vehicle 12 during an in-use charging state of the electric vehicle 12.

Lowering of the charging plug 20 may be achieved by unspooling a retractable charging cable 24 that couples the charging plug 20 to the electric vehicle car battery. In this instance, the electric vehicle 12 includes an electric-vehicle spool 26, around which the retractable charging cable 24 is wound. The electric-vehicle spool 26 may include a spool motor which controls rotational motion of the electric-vehicle spool 26, and thus controls the lowering and raising of the charging plug 20 with respect to the undercarriage 22 of the electric vehicle 12.

In this present example of the automatic electric vehicle charging system 10, the charging plug 20 depends from a central location of the undercarriage 22 of the electric vehicle 12, and more specifically, between a front car axle and a rear car axle. In this case, the electric-vehicle spool 26 is also located in the central location of the undercarriage 22 of the electric vehicle 12.

The autonomous charging robot 14 has a mobile chassis, a spoolable charging cable 18 which is at least partly within the chassis, and a charging socket (first shown in detail in Figure 5) onboard the chassis, the charging socket being coupled to the charging cable 18. In this instance, the autonomous charging robot 14 has a connection to a low voltage conductor of the charging cable 18 supply power for powering movement of the mobile chassis. Similarly, the charging socket may have a connection to a high voltage conductor of the charging cable 18 for charging of the electric vehicle 12.

The autonomous charging robot 14, as shown in Figure 1, is in a stand-by condition whereby the autonomous charging robot 14 is at a docked position near the base station 16.

Coupled to the autonomous charging robot 14 by way of the charging cable 18, is the base station 16. In this scenario, the charging cable 18 of the autonomous charging robot 14 is sub-surface routed.

The power supply of the base station 16 is preferably provided by way of national grid infrastructure, and more preferably national electrical distribution infrastructure. The charging cable 18 can be or include a single cable, a flexible multicore cable or may be multiple cables contained within a flexible ducting. The charging cable 18, in this instance, includes at least two conductors including the aforementioned low voltage conductor and the high voltage conductor. More specifically, the low voltage conductor may be an extra-low voltage conductor whilst the high voltage conductor may be a 240V conductor.

Referring now to Figure 2, there is shown the automatic electric vehicle charging system 10 with the autonomous charging robot 14 in a charging condition, which may be referred to as a charging state. The charging plug 20 of the electric vehicle 12 is received by the charging socket of the autonomous charging robot 14. The power supply is electrically connected to the electric vehicle car battery by way of the charging cable 18 being coupled to the charging socket of the autonomous charging robot 14, and the charging plug 20 being plugged into the charging socket.

Referring now to Figure 3, there is shown the automatic electric vehicle charging system 10 after the electric vehicle car battery has been charged. The autonomous charging robot 14 returns to the docked position after disconnection of the charging plug 20 from the charging socket.

Referring now to Figures 1 to 3, the charging plug 20 descends from the undercarriage 22 of the electric vehicle 12 by the electric-vehicle spool 26 unwinding the retractable charging cable 24 wound thereon. The charging plug 20 may contact a floor of a parking space 23, at which point the electric-vehicle spool 26 stops.

A signal may be emitted from the electric vehicle 12 by a transmitter, and possibly from the charging plug 20 in the instance where the transmitter is located on the charging plug 20. In this case, the autonomous charging robot 14, may include a pathfinding controller and a receiver which is in data communication with the pathfinding controller.

The receiver may receive the signal and the pathfinding robot controls the mobile chassis to move the autonomous charging robot 14 from the docked position to the charging plug 20. Power to move the mobile chassis is provided by way of the low voltage conductor.

The charging socket then receives the charging plug 20 and charges the electric vehicle car battery by way of the high voltage conductor. Upon completion of charging and/or upon receipt of a completion command issued from the electric vehicle 12 to the autonomous charging robot 14, the charging plug 20 is disconnected from the charging socket. The electric-vehicle spool 26 winds the retractable charging cable 24 around the electric-vehicle spool 26 and the charging plug 20 is retracted into the electric vehicle 12. The provision of the electric-vehicle spool 26 insider the housing ensures that the charging cable 18 is not dragged but laid on the floor. Simultaneously or sequentially, the autonomous charging robot 14 moves back to the docked position near the base station 16 as controlled by the pathfinding controller, or alternatively, the autonomous charging robot 14 may move back to the docked position with the spool motor 50 using a cable as a pathfinder, as a spooling back cable.

Additionally, or alternatively, the control of autonomous charging robot 14 may be controlled by computer applications, for instance, from a user device such as a smartphone.

A length of exposed charging cable 18 between the base station 16 and the autonomous charging robot 14 varies with movement of the autonomous charging robot 14. The charging cable 18 may spool within the base station 16 and/or the autonomous charging robot 14. As such, the base station 16 may include a base-station spool and/or the autonomous charging robot 14 may include a spool. Each said spools may also be motorised to assist winding and unwinding of the charging cable 18 on the aforementioned said spools. The charging cable 18 may be sufficiently long for the autonomous charging robot 14 to access multiple parking spaces from their base station 16. This may cause a trip hazard, however, and may require control via a programmable logic controller.

The base station 16 may include safety circuits which can cut the power supply in the instance of an emergency. The safety circuits may include, a differential current device, an overload protection device, a temperature sensor and a smoke detector.

Referring now to Figure 4, there is shown the autonomous charging robot 14 in more detail. The mobile chassis includes a driving wheel 32 and a first support wheel 34 and a second support wheel 36, the wheels are indicated by dashed lines denoting their placement on the underside of the autonomous charging robot 14 with respect to this top plan view.

The autonomous charging robot 14 includes a housing 30 to cover, at least in part, the mobile chassis. The housing 30 is preferably a spherical cap shape, such that the top plan view of Figure 4 is circular, whilst the top surface of the housing 30 is rounded.

The housing 30 includes an access opening 38 to in-use, receive the charging plug 20 therethrough for engagement with the charging socket. The access opening 38 in this instance is covered with a retractable cover. The retractable cover may include first and second retractable covers 40a, 40b.

The autonomous charging robot 14 may also include a light emitting diode 42. The light emitting diode 42 indicates the various states of the automatic electric vehicle charging system 10, included but not limited to, red for a fault, and green for indicating that the autonomous charging robot 14 is ready to charge.

Fault detection of the automatic electric vehicle charging system 10 may be realised by the autonomous charging robot 14 having a sensor or sensors, including but not limited to, a moisture sensor, a water sensor, a smoke detector, an overrunning sensor, a differential current detector, an accelerometer, a voltmeter, an ammeter, smoke detector and/or a thermocouple and/or combination thereof. The sensor or sensors in this instance may be in data communication with an onboard processor which may be or may include the pathfinding controller. Additionally, the light emitting diode 42 may be connected to the onboard processor. The onboard processor may be in data communication with an external device and/or server for the purposes of fault reporting.

Referring now to Figure 5, there is shown a cross-sectional plan view of the autonomous charging robot 14 showing the access opening 38, the charging socket 28, the driving wheel 32, the first support wheel 34, the second support wheel 36, a spool 44, the spoolable charging cable 18 and the base station 16.

The access opening 38 of the housing 30 provides the charging plug 20 of the electric vehicle 12 with access to the charging socket 28 which is shown in an open condition. The charging socket 28 in this instance comprises a first socket portion 28a and a second socket portion 28b. The first socket portion 28a is moveably connected to the second socket portion 28b. The first socket portion 28a may also be considered to be hingeably connected to the second socket portion 28b, whereby the first and second socket portions 28a, 28b are connected about a hinge 46. The hinge 46 may be static with respect to the autonomous charging robot 14 and about which both the first and second socket portions 28a, 28b hinge or rotate.

Relative movement between the first socket portion 28a and the second socket portion 28b may be actuated by an actuator element. The actuator element in this instance comprises a first-socket actuator 48a and a second-socket actuator 48b to actuate the first socket portion 28a and the second socket portion 28b, respectively. Each said actuator may have a socket portion connection to connect one end of the actuator to the respective socket portions and an anchor connection to connect the other end of each actuator to the mobile chassis. Additionally, each said actuator may be a solenoid actuator.

The spoolable charging cable 18, which may be more simply referred to as the charging cable, is wound around the spool 44. The spool 44 in this instance is located towards or at the centre of the autonomous charging robot 14. Winding and unwinding of the charging cable 18 around the spool 44 shortens and lengthens the length of exposed charging cable 18 between the base station 16 and the autonomous charging robot 14. Rotational motion of the spool 44 may be actuated by a spool motor 50.

The driving wheel 32 may be driven by a driving-wheel motor 52 about a first axis of rotation, realising two degrees of freedom of the mobile chassis, and more specifically forwards and backwards. The driving wheel 32 may also include a second axis of rotation, realising third and fourth degrees of freedom, and more specifically left and right. Rotation of the driving wheel 32 about the second axis of rotation may be realised by the driving-wheel motor 52.

Referring now to Figure 6, there is shown a side view of the autonomous charging robot 14, whereby the three-dimensional part-spherical cap shape of the housing 30 is evident. The underside is planar such that the housing 30 includes a planar road-facing portion 54.

The driving wheel 32 is visible through the access opening 38 and the first and second support wheels are visible on either side of the access opening 38.

Referring now to Figure 7, there is shown another representation of the side view of the autonomous charging robot 14 as a car wheel drives over the autonomous charging robot 14. The driving wheel 32 and first and second support wheels 34, 36 each include a depression element connecting each said wheel to the mobile chassis. Each said depression elements may be a spring with a predetermined spring constant.

In-use, as the car wheel travels over the autonomous charging robot 14, the spherical cap shape of the housing 30 minimises any lateral force applied to the autonomous charging robot 14 and maximises any downward applied force. The depression element allows the driving wheel 32, the first support wheel 34 and the second support wheel 36 to be received within the housing 30 upon the application of a downward force that exceeds a force threshold. The force threshold may be realised by the predetermined spring constant of each said spring. The planar road-facing portion 52 of the housing 30 engages the parking space 23, locking the autonomous charging robot 14 in place to allow the car wheel to safely travel over the autonomous charging robot 14.

Referring now to Figure 8, there is shown the charging socket 28 of the autonomous charging robot 14 in a closed condition. The first socket portion 28a includes a first plug receiving surface 54a. Likewise, the second socket portion 28b includes a second plug receiving surface 54b. Together, when the charging socket 28 is in the closed condition, the first and second plug receiving surfaces 54a, 54b have an infinite degree of rotational symmetry in a vertical axis. The vertical axis being, or substantially being, orthogonal to the planar road-facing portion 52 of the housing 30. The first and second plug receiving surfaces 54a, 54b are complementary to the charging plug 20 of the electric vehicle 12 and will be discussed in more detail below.

The charging socket 28 includes a safety switch, and in this case, the safety switch comprises a first contact 56a mounted on the first socket portion 28a and a second contact 56b mounted on the second socket portion 28b. The first contact 56a is mounted at an edge of the first socket portion 28a that opposes the location of the hinge 46, likewise, the second contact 56b is mounted at an edge of the second socket portion 28b that opposes the location of the hinge 46. Wth the charging socket 28 in the closed condition, the first and second contacts 56a, 56b touch, such that the safety switch is in a closed condition. The closed condition of the safety swich allows the power supply to be conducted through the high voltage conductor of the charging cable 18 to the charging socket 28 and to the charging plug 20 when the autonomous charging robot 14 is in the charging condition.

Referring now to Figure 9, there is shown the charging socket 28 of the autonomous charging robot 14 in an open condition, and thus the safety switch is also in an open condition. In the open condition the first contact 56a is separated from the second contact 56b, and the first socket portion 28a is engaged to the second socket portion 28b about the hinge 46.

Referring now to Figure 10, there is shown a cross-sectional side view of the electric vehicle 12 as shown in Figure 1, showing the longitudinal positioning of the charging plug 20 with respect to an electric-vehicle chassis. Description of some feature shown, and that have been discussed with respect to Figure 1, have been omitted for brevity.

The electric vehicle 12 comprises the electric-vehicle spool 26, the spool motor, the retractable charging cable 24 and charging plug 20. The electric-vehicle spool 26, the spool motor, the retractable charging cable 24 and charging plug 20 may be housable in a charging plug housing 58 which may be referred to as a connector box. The charging plug housing 58 is fitted between the front and rear axles of the electric vehicle 12 and more specifically, in line with a driver's seat 59a.

The charging plug housing 58 is within the undercarriage 22 of the electric vehicle 12 such that when the retractable charging cable 24 is fully wound around the electric-vehicle spool 26, the charging plug 20 does not protrude or depend from the undercarriage 22 of the electric vehicle 12. However, in this scenario, the charging plug 20 contacts a parking space surface and is ready to be received within the charging socket 28.

Referring now to Figure 11, there is shown a rear view of the electric vehicle 12. This view illustrates the lateral positioning of the charging plug housing 58 which houses the electric-vehicle spool 26, the spool motor and the retractable charging cable 24 in this particular scenario. The aforementioned lateral positioning being between the driver's seat 59a and a front passenger seat 59b.

Referring now to Figures 12a, 12b and 12c, there is shown the charging plug 20 with the retractable charging cable 24 extending there from. The charging plug 20 has an infinite order of rotational symmetry in a rotational axis 60 that is or substantially is orthogonal to the undercarriage 22 of the electric vehicle 12. The charging plug 20 in-use is complementarily received within the charging socket during the charging condition.

In this instance, there are three circular contacts 62a, 62b, 62c, it will be appreciated that these are preferably copper circular contacts. The three circular contacts 62a, 62b, 62c correspond to a three-phase power supply. It will be appreciated that there may be two circular contacts in the instance of a single-phase supply or a direct current supply. There may also be two further circular contacts corresponding to an earth contact 64 and a low voltage circular contact 66. The low voltage circular contact 66 may be considered to be an extra-low voltage circular contact for in-use connection with the extra-low voltage conductor of the charging cable 18. A further small-diameter circular contact 68 may also be included on the charging plug 20 which may be a signal circular contact.

Protruding between each said circular contacts are electrically-insulating portions 70, which in this instance protrude from an insulating core 72, the circular contacts 62a, 62b, 62c, 64, 68 being mounted on the insulating core 72. Within the insulating core 72, there are connections, connecting the circular contacts 62a, 62b, 62c, 64, 68 to conductors which are included in the retractable charging cable 24.

It will be appreciated that complementary protruding electrical contacts and recessed insulating receiving portions are included in the charging socket, and more specifically, on the first and second plug receiving surfaces 54a, 54b.

The charging plug 20, in this instance also includes a vertical switch 76, which may be a push switch and may also be referred to as a stop switch. In-use, as the charging plug 20 is lowered from the undercarriage 22 of the electric vehicle, which may be by way of unwinding the retractable charging cable 24 from the electric-vehicle spool 26, the vertical switch 76 is activated upon contact with the parking space surface. The activation of the vertical switch 76 halts the descent of the charging plug 20, which may be by way of halting the rotational motion of the electric-vehicle spool 26. A vertical height of the charging plug 20 with respect to the parking space surface is set upon activation of the vertical switch 76 such that the autonomous charging robot 14 can receive the charging plug 20 within the charging socket.

In-use, the automatic electric vehicle charging system 10 is first provided. The electric vehicle parks in the parking space 23 near the base station 16 and the autonomous charging robot 14, the autonomous charging robot 14 being in the stand-by condition.

The light emitting diode 42 is green, indicating no faults detected by the sensors and the autonomous charging robot 14 is ready. If a fault is detected by the sensors, the light emitting diode 42 will be red and the fault is automatically reported to the external device and/or the server. Such faults may include, flooding, fire, overheating, overrunning and electrical faults.

After engaging a parking brake and switching off an ignition of the electric vehicle, a user may issue a charge command from the driver's seat 59a, and more preferably by interaction with a dashboard. The retractable charging cable 24 may be unspooled from the electric-vehicle spool 26 such that the charging plug 20 descends from the undercarriage 22 of the electric vehicle. Upon activation of the vertical switch 76 of the charging plug 20, the electric-vehicle spool 26 stops unwinding. The electric-vehicle spool 26 may be reversed slightly to wind the retractable charging cable 24 thereon, adjusting the vertical height of the charging plug 20 for receipt in the charging socket.

Simultaneously or sequentially to the unwinding of the charging plug 20, the autonomous charging robot 14 receives the charge command which may be a signal received by the receiver from the transmitter. Transmittal of the charge command may be by way of wireless communication including, but not limited to, Bluetooth communication from the electric vehicle. If the sensor or sensors do not detect a fault, the autonomous charging robot 14 moves to the charging plug 20 using the path finding controller from the docked position.

The charging socket can then receive the charging plug 20 therein. This may be realised by the first and second socket portions 28a, 28b achieving the open condition by rotation about the hinge 46. Once the charging plug 20 is received in or by the charging socket, the charging process may begin.

In the instance where the first and second socket portions 28a, 28b are provided, the first and second socket portions 28a, 28b may rotate about the hinge 46 to achieve the closed condition, akin to a biting' motion. The first and second contacts 56a, 56b touch to close the safety switch such that a high voltage power supply can be provided to charge the electric vehicle.

The autonomous charging robot 14 and/or base station 16 may perform a final check for any faults using the sensors and/ or the safety switch before the power supply can be supplied by the base station 16 to the electric vehicle battery via the charging cable 18, the charging socket, and the charging plug 20. More preferably, the power supply may be a high voltage supply, and more preferably a 240V supply via the high voltage conductor of the charging cable 18.

After the electric vehicle car battery is fully charged and/or a disconnect command is issued by the user from the driver's seat 59a or a fault was detected or the safety switch was opened, the high-voltage power supply to the autonomous charging robot 14 is stopped, for example, by a contactor or relay in the control panel. Only low voltage may be present to the autonomous charging robot 14 to monitor the faults and control the system. The charging plug 20 is disconnected from the charging socket, preferably by opening the first and second socket portions 28a, 28b. The autonomous charging robot 14 moves back to the docked position either by driving using the pathfinding controller or by spooling the charging cable 18 back into the autonomous charging robot 14 and/or the base station 16. Simultaneously or sequentially, the charging plug 20 is retracted back into the undercarriage 22 of the electric vehicle.

The electric vehicle may have a unique identifier that the autonomous charging robot 14 may be able to identify for a payment transaction.

Referring now to Figure 13, there is shown an autonomous charging robot 114, a docking housing 178, and a base station 116 of a second embodiment of an automatic electric vehicle charging system. Description of like or similar features of this present embodiment compared to that disclosed in Figures 1 to 12c have been omitted for brevity.

The autonomous charging robot 114, the docking housing 178 and the base station 116 are based near, or adjacent to a parking space 123 and more preferably, a public parking space 123. The docking housing 178 in this instance is in a pavement. The docking housing 178 and the parking space 123 are elevated above a road. In other instances, the docking housing 178 may be elevated with a ramp down to the parking space 123. However, it will be appreciated that the docking housing 178 and parking space 123 may not be elevated.

Referring now to Figure 14, there is shown a base station 216 and a plurality of autonomous charging robots 214 of a third embodiment of an automatic electric vehicle charging system. Description of like or similar features of this present embodiment compared to that disclosed in Figures 1 to 12c have been omitted for brevity.

In this instance, the automatic electric vehicle charging system includes the plurality of autonomous charging robots 214 each connected to the base station 216. The base station 216 in this instance includes a multi-axial cable 280, the multi-axial cable 280 comprises a plurality of conductors, each conductor of the plurality of conductors is connected to a corresponding charging cable 218 of an autonomous charging robot of the plurality of autonomous charging robots 214.

An autonomous charging robot may also be provided, independent of the electric vehicle and/or the base station. The autonomous charging robot, in this instance may comprise a mobile chassis, a spoolable charging cable which is at least partly within the chassis; and a charging socket onboard the chassis and coupled with the charging cable, the charging socket being configured to in-use receive a counterpart charging plug of an electric vehicle which depends from the undercarriage thereof. The charging socket may be reconfigurable between an open condition, in which the charging socket is opened to receive the counterpart charging plug, and a closed condition in which the charging socket is engaged with the coupled counterpart charging plug.

It will be appreciated that in all the example embodiments of the automatic electric vehicle that the length of the charging cable may control or limit a radius of travel of the autonomous charging robot from the docked position.

Although a charging plug has been discussed as depending from a central location of the undercarriage of an electric vehicle, it will be appreciated that this may not necessarily be the case. In other instances, the charging plug may depend from a lateral side, front or rear side of the electric vehicle.

Furthermore, although the charging plug has been described as being electrically connected to an electric vehicle car battery, in other instances, electric connections may also be made to the other electrical assets of the electric vehicle, including but not limited to, the lights and air conditioning.

The charging plug and associated features have been described as being of the electric vehicle, it will be appreciated that these may be retrofitted to current electric vehicles.

It will be appreciated that in the automatic electric vehicle charging system and any components thereof may be adapted to suit different circumstances. For example, for large electric vehicle such as buses, the charging plug and socket may be larger compared to those used in smaller cars. In another example, an electric vehicle may comprise two or more charging plugs for connection with two or more autonomous charging robots.

Although the mobile chassis has been described as being realised by a single drive wheel and two support wheels, it will be appreciated that four or more wheels or mobile elements may be employed to facilitate movement of the autonomous charging robot.

It is therefore possible to provide an automatic electric vehicle charging system with an autonomous charging robot for a fully automated charging process of electric vehicles. Additionally, it is also possible to provide an autonomous charging robot for an automatic electric vehicle charging system.

The words 'comprises/comprising' and the words 'having/including' when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps, or components, but do not preclude the presence or addition of one or more other features, integers, steps, components, or groups thereof.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

The embodiments described above are provided by way of examples only, and various other modifications will be apparent to persons skilled in the field without departing from the scope of the invention as defined herein.

Claims

CLAIMS1. An automatic electric vehicle charging system comprising: an electric vehicle having an undercarriage and a charging plug which depends from the undercarriage during an in-use charging state of the electric vehicle; and an autonomous charging robot having a mobile chassis, a spoolable charging cable which is at least partly within the mobile chassis, and a charging socket onboard the mobile chassis and coupled with the charging cable, the charging socket being configured to in-use receive the charging plug of the electric vehicle; and a base station having a power supply which is connected to the charging cable of the autonomous charging robot; the autonomous charging robot further comprising a pathfinding controller for autonomously controlling a movement of the autonomous charging robot between the base station and the electric vehicle.
2. An automatic electric vehicle charging system as claimed in claim 1, wherein the charging socket is reconfigurable between an open condition, in which the charging socket is opened to receive the counterpart charging plug, and a closed condition in which the charging socket is engagable with the coupled counterpart charging plug.
3. An automatic electric vehicle charging system as claimed in claim 2, wherein the charging socket includes a safety switch, the safety switch being closed when the charging socket is in the closed condition.
4. An automatic electric vehicle charging system as claimed in claim 2 or claim 3, wherein the charging socket comprises a first socket portion and a second socket portion, the first socket portion being moveably connected to the second socket portion, wherein the open condition and the closed condition can at least be in part achieved by movement between the first and second socket portions.
5. An automatic electric vehicle charging system as claimed in claim 4 when dependent on claim 3, wherein the safety swich includes a first contact mounted on the first socket portion and a second contact mounted on the second socket portion.
6. An automatic electric vehicle charging system as claimed in any one of the preceding claims, wherein the autonomous charging robot comprises a housing to at least in part cover the mobile chassis.
7. An automatic electric vehicle charging system as claimed in claim 6, wherein the housing has a spherical cap shape.
8. An automatic electric vehicle charging system as claimed in claim 6 or claim 7, wherein the housing includes a planar road-facing portion.
9. An automatic electric vehicle charging system as claimed in any one of claims 6 to 8, wherein the housing includes an access opening to in-use receive the charging plug of the electric vehicle therethrough.
10. An automatic electric vehicle charging system as claimed in claim 9, wherein the access opening includes a retractable cover.
11. An automatic electric vehicle charging system as claimed in any one of the preceding claims, wherein the mobile chassis includes a driving wheel and first and second support wheels.
12. An automatic electric vehicle charging system as claimed in claim 11, wherein the driving wheel and first and second support wheels each include a depression element to allow each said wheel to be depressed into the mobile chassis upon the application of an in-use downward force that exceeds a force threshold.
13. An automatic electric vehicle charging system as claimed in any one of the preceding claims, wherein the charging plug is retractable with respect to the undercarriage.
14. An automatic electric vehicle charging system as claimed in claim 13, wherein the electric vehicle includes an electric-vehicle spool that is motorised to spool a retractable charging cable within the electric vehicle, the retractable charging cable being coupled to the charging plug.
15. An automatic electric vehicle charging system as claimed in any one of the preceding claims, wherein the charging plug has an infinite order of rotational symmetry in a rotation axis that is or substantially is orthogonal to the undercarriage of the electric vehicle.
16. An automatic electric vehicle charging system as claimed in claim 15, wherein the charging plug comprises at least one circular contact, and the charging socket includes at least one complementary contact.
17. An automatic electric vehicle charging system as claimed in any one of the preceding claims, wherein the base station includes a base-station spool for spooling the charging cable within the base unit.
18. An automatic electric vehicle charging system as claimed in any one of the preceding claims, wherein the base station includes a temperature sensitive power cut-off and/or an electrical sensitive power cut-off.
19. An automatic electric vehicle charging system as claimed in any one of the preceding claims, wherein the charging cable includes a low voltage conductor and a high voltage conductor, the low voltage conductor being connected to the autonomous charging robot for supplying power to the mobile chassis and the high voltage conductor being coupled to the charging socket.
20. An automatic electric vehicle charging method comprising the steps of: a] providing an automatic electric vehicle charging system as claimed in any one of the preceding claims; b] moving the autonomous charging robot, using the pathfinding controller, from the base station to the charging plug of the electric vehicle and spooling the charging cable thereof; c] receiving the charging plug by the charging socket; and d] charging the electric vehicle by the power supply.
21. An automatic electric vehicle charging method as claimed in claim 20 when dependent on claim 2, comprising a step prior to step c] of, opening the charging socket of the autonomous charging robot, and wherein during step c] includes closing the charging socket of the autonomous charging robot around the received said charging plug.
22. An automatic electric vehicle charging method as claimed in claim 20 or claim 21, further comprising a step after step a] and before step b] of, instructing the autonomous charging robot to charge the electric vehicle.
23. An automatic electric vehicle charging method as claimed in any one of claims 20 to 22, comprising a step after step d] of moving the autonomous charging robot away from the electric vehicle and towards a docked position near the base station.
24. An autonomous charging robot for autonomously locating and charging an electric vehicle, the autonomous charging robot comprising: a mobile chassis; a spoolable charging cable which is at least partly within the chassis; and a charging socket onboard the chassis and coupled with the charging cable, the charging socket being configured to in-use receive a counterpart charging plug of an electric vehicle which depends from the undercarriage thereof; wherein the charging socket is reconfigurable between an open condition, in which the charging socket is opened to receive the counterpart charging plug, and a closed condition in which the charging socket is engaged with the coupled counterpart charging plug.