Modular wireless power transmission antennas

Abstract

A modular antenna system for providing Wireless Power Transmission (WPT) from a power transmitter to a receiver of a rechargeable vehicle moving in a working environment, comprising modular antenna tiles configured to be coupled together and mounted and on a surface of the work environment. One or more modular antenna tile of the plurality comprises an active region with an antenna element that provides WPT upwardly; a center tile for laterally protecting the active region using a base frame surrounding the active region; a circumferential ramp frame that is formed by ramp segments being coupled to corresponding edges of the center tile and corner ramp segments for filling corresponding gaps between adjacent ramp segments; a bottom layer being an electrically conductive shield plate, for avoiding the leakage of electric fields at the bottom of the active region; strip antenna(s) for Wireless Power Transmission (WPT) received from the power transmitter; an encapsulation layer overlaying the strip antennas and the conductive shield plate; a top protective layer, overlaying the encapsulation layer, for providing mechanical protection to the modular antenna tile; male connectors and / or female sockets for receiving a male connector such that the antenna tile is mechanically connected to adjacent antenna tiles to form a desired antenna pattern and maintain electrical contact between corresponding strip antennas of adjacent antenna tiles.

Description

[0001] MODULAR WIRELESS POWER TRANSMISSION ANTENNAS

[0002] Field of the Invention

[0003] The present invention relates to the field of wireless power transmission. More particularly, the present invention relates to a modular antenna system, designed to support the strict requirements of wide area Wireless Power Transmission (WPT) for autonomous mobile robotic systems.

[0004] Background of the Invention

[0005] Autonomous technology, in particular autonomous mobile robots, is a rapidly growing technology in many fields such as: factories, warehouses, logistics centers, restaurants, hospitals. The need for such robots to perform more sophisticated tasks at much higher capacity is therefore, essential. The latter translates to increased energy requirements. Typical charging of such robots is performed either by plugging into a power socket to receive energy, or by assuming a particular pose to receive wirelessly transmitted energy. However, these types of charging entail striking robots for the entire charging period.

[0006] In order to support their functions in the working environments in which they operate, it is essential that these robots are not required to stop for charging at designated power stations. Existing advanced high-performance wireless power technologies can provide a solution. However, providing a wireless power system that is operable and practical to provide robots with the required energy while moving to carry out their assigned tasks in their working environments is a complex challenge, due to several reasons.

[0007] The first reason is that typically such robots require power levels of several hundred of Watts, which induce very strong electromagnetic fields that can overheat the transmitting antenna. Another reason is that wireless high-power levels might cause significant electromagnetic radiation which may interrupt the operation of neighboring systems.

[0008] Also, in wirelessly charged mobile robots, the antenna is typically deployed on the floor of their working environment and therefore, the antenna is exposed to high weights of loaded robots. Another challenge is the thickness of the antenna, which should not exceed 1-2 cm. Otherwise, a moving robot will have to climb a step and be inclined while moving with a heavy load. This may endanger the stability of the robot. Too thick antennas require excavation in the floor in order to reduce or eliminate the unwanted step. Such excavation is costly, cumbersome, and limits the deployment flexibility.

[0009] It is therefore an object of the present invention to provide a modular antenna design for supporting wide area Wireless Power Transmission (WPT) for mobile robotic systems while being static or in motion.

[0010] It is another object of the present invention to provide materials stack up design method for high-performance wireless power antennas.

[0011] It is another object of the present invention to provide a modular antenna system that is sufficiently thin to be deployed directly on the floor.

[0012] It is a further object of the present invention to provide a modular antenna system that is sufficiently rigid to carry heavy-duty robots.

[0013] Other objects and advantages of the invention will become apparent as the description proceeds.

[0014] Summary of the Invention

[0015] A modular antenna system for providing Wireless Power Transmission (WPT) from a power transmitter to a receiver of a rechargeable vehicle moving in a working environment, comprising: a) a plurality of modular antenna tiles configured to be coupled together and mounted and on one or more surfaces of the work environment, at least one modular antenna tile of the plurality comprises: a.l) an active region, located essentially at the center of the modular antenna tile with an antenna element that provides Wireless Power Transmission (WPT) upwardly; a.2) a center tile for laterally protecting the active region using a base frame surrounding the active region; a.2) a circumferential ramp frame that is formed by ramp segments being coupled to corresponding edges of the center tile and corner ramp segments for filling corresponding gaps between adjacent ramp segments; a.2) a bottom layer being an electrically conductive shield plate, for avoiding the leakage of electric fields at the bottom of the active region; a.2) at least one strip antenna(s) for Wireless Power Transmission (WPT) received from the power transmitter; a.2) an encapsulation layer overlaying the at least one strip antennas and the conductive shield plate, to encapsulate the strip antennas; a.2) a top protective layer, overlaying the encapsulation layer, for providing mechanical protection to the modular antenna tile; and b) at least one male connector and / or at least one female socket for receiving a male connector such that the antenna tile is mechanically connected to one or more adjacent antenna tiles to form a desired antenna pattern and maintain electrical contact between corresponding strip antennas of adjacent antenna tiles.

[0016] At least one modular antenna tile of the plurality of modular antenna tiles is a feeder tile, for coupling the modular antenna tile to an antenna driver that provides electrical power to be transmitted to the rechargeable vehicle.

[0017] The feeder tile may function as a bridge tile for connecting two modular antenna tiles. At least one modular antenna tile of the plurality of modular antenna tiles may be an isolation tiles that connects two modular antenna tiles mechanically but not electrically.

[0018] At least one modular antenna tile of the plurality of modular antenna tiles may be a gap tile being connected to a male connector or female socket of a modular antenna tile, for blocking the female socket form being used to connect between adjacent tiles.

[0019] The desired antenna pattern may form a straight line antenna tile; a right angle antenna tile; or an elbow antenna tile.

[0020] The plurality of via holes may be formed in the bottom face of the center tile, for inserting a corresponding plurality of screws, for allowing fastening all the layers together.

[0021] Modular antenna tiles may be connected together by integrating a terminal connection box with bridge terminals between adjacent antenna tiles.

[0022] The rechargeable vehicle may be a wheeled robot or a robot equipped with caterpillar tracks.

[0023] Antenna tiles may be deployed directly on the floor of the working environment at positions past which rechargeable vehicles move.

[0024] The thickness of the antenna tiles may not exceed 1 cm.

[0025] The center tile may be made of a high-density fiberboard or high-density plastics, for obtaining mechanical durability and being capable of operating under high magnitudes of electro-magnetic fields. Each ramp segments may be made of a durable inclined metal base ramp tile that allows a rechargeable vehicle to approach the antenna system from any direction, without compromising robot's balance.

[0026] The strip antennas may be supported by a honeycomb substrate made of foamed PVC (polyvinylchloride) or any other thermoplastic polymers, bonded to the conductive shield plate.

[0027] The top protective layer may be formed from a Compact Density Fiberboard (CDF) or thermoplastic polymers, overlaying the encapsulation layer.

[0028] The conductive shield plate may be configured to be bonded or mechanically mounted to a surface of the work environment.

[0029] The modular antenna system may further comprise plurality of screws for fastening together all the layers.

[0030] At least one antenna tile may comprise a stack of layers, sandwiched between the bottom layer and the top protective layer.

[0031] The modular antenna system may further comprise transmitter boxes with corresponding antenna tiles deployed next to each other, wherein the antenna tiles are connected together such that wiring between antennas and the transmitter boxes is deployed through one antenna tile to the adjacent antenna tile, whereas the wiring is shielded. Such deployment allows to expand the overall charging area and potentially double the overall transmitted power.

[0032] The modular antenna system may further comprise spring loaders, for preventing detachment of tiles. Brief Description of the Drawings

[0033] The above and other characteristics and advantages of the invention will be better understood through the following illustrative and non-limitative detailed description of preferred embodiments thereof, with reference to the appended drawings, wherein:

[0034] Fig. 1A schematically shows a top planar view of a straight line tile, in accordance with an embodiment of the invention;

[0035] Fig. IB schematically shows top planar views of a right angle antenna tile and an elbow antenna, in accordance with an embodiment of the invention;

[0036] Fig. 1C schematically illustrates different shaped feeder and bridge tiles 200, in accordance with an embodiment of the invention;

[0037] Fig. ID schematically shows different isolation bridge tiles, in accordance with an embodiment of the invention;

[0038] Fig. IE schematically shows different stop tiles, in accordance with an embodiment of the invention;

[0039] Fig. 2 shows a schematic layout of modular antenna tiles, configured to provide WPT to a robot (not shown), in accordance with an embodiment of the invention;

[0040] Fig. 3A illustrates a top view of a modular basic antenna tile, according to an embodiment of the invention;

[0041] Fig. 3B illustrates a bottom view of the modular basic antenna tile, according to an embodiment of the invention;

[0042] Figs. 4A-4D illustrate top and bottom views of the center tile, ramp segments and of the modular basic antenna tile, according to an embodiment of the invention;

[0043] Fig. 5 illustrates an antenna tile which comprises a stack of layers;

[0044] Figs. 6A-6C illustrate modular assembly of several antenna tiles to create desired antenna patterns, according to an embodiment of the invention;

[0045] Figs. 7A-7B illustrate another option for joining antennas together is by integrating a connection box with bridge terminals between antennas, according to an embodiment of the invention; and Fig. 8 illustrates another embodiment highlighting another advantage of the modular antenna concept, where two transmitters, each comprising a transmitter box and two antennas that are deployed next to each other.

[0046] Detailed Description of the Present Invention

[0047] The present invention provides a modular antenna system for supporting wide area Wireless Power Transmission (WPT) for mobile autonomous static or moving robotic systems, while carrying out transportation tasks for which they were intended. Such modularity enables to create different surfaces for different deployments and floorplans of the facility, with minimal customization. The proposed system is sufficiently thin to be deployed directly on the floor and sufficiently rigid to carry heavy-duty loaded robots. Modularity is implemented by a plurality of modular antenna tiles configured to be mounted and coupled together on surfaces of the work environment (typically, on the floor) at positions past which the robots move, while engaging in their tasks. Each antenna tile comprises a stack of layers sandwiched between a bottom baseplate layer and a top protective layer (any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling) for providing mechanical protection to the modular antenna tile.

[0048] In an embodiment, each antenna tile is formed having at least one male connector and / or at least one female socket for receiving a male connector such that a first antenna tile may be robustly and mechanically connected to a second antenna tile and the at least one antenna in the first and the second tiles held in secure electrical contact. Optionally, at least one male connector and / or at the at least one female socket in the first antenna tile or the second antenna tile comprises at least one spring loaded electrical contact (a type of electrical connector mechanism with spring plungers that is used in electronic applications) for maintaining electrical contact between the antenna in the first and second antenna tiles, when the tiles are connected (or maintain electrical contact between corresponding strip antennas of adjacent antenna tiles). In an embodiment the first and second antenna tiles comprise only female sockets and the tiles are mechanically and electrically connected by at least one male "tie connector", optionally comprising at least one spring loaded electrical contact. The tie connector is configured to lock into a female socket in the first antenna tile and a female socket in the second antenna tile to join the tiles mechanically and electrically.

[0049] In an embodiment, the modular antenna comprises feeder tiles for coupling an antenna tile to an antenna driver that provides the antenna with electrical power for transmitting energy to a robot. A feeder tile may function as a bridge tile for connecting two antenna tiles. The modular antenna optionally comprises isolation bridge tiles that may be used to connect two antenna tiles mechanically but not electrically. The modular antenna may also comprise gap tiles that connect to a male connector or female socket of an antenna tile to block the socket form being used to connect the tile to another tile.

[0050] Fig. 1A schematically shows a top planar view of a straight line tile 110 comprising a strip antenna 120 formed with female sockets 122 for joining the modular antenna tile to another modular antenna tile, using male tile connectors 130. The male tie connectors are used to connect two antenna tiles 120.

[0051] Fig. IB schematically shows top planar views of a right angle antenna tile 140 and an elbow antenna tile 150, in accordance with an embodiment of the invention. As in straight line antenna 120, grey shaded bands represent strip antenna in tiles 140 and 150, and by way of example, each of tiles 140 and 150 comprise both female socket connectors 142 and 152 respectively and male plug connectors 144 and 154, respectively. The design of various antenna tile has an efficient form factor (that defines and prescribes the size, shape, and other physical specifications).

[0052] Fig. 1C schematically illustrates different shaped feeder and bridge tiles 200, in accordance with an embodiment of the invention. Fig. ID schematically shows different isolation bridge tiles, which comprise male and / or female connectors but are absent strip antennas represented by grey bands, and may be used to connect modular antenna tiles mechanically but not electrically, in accordance with an embodiment of the invention.

[0053] Fig. IE schematically shows different stop tiles, as in the case of isolation bridge tiles absent strip antennas, in accordance with an embodiment of the invention.

[0054] Fig. 2 shows a schematic layout of modular basic antenna tiles that form a modular antenna system and are configured to provide WPT to a rechargeable vehicle such as a robot, (not shown) in accordance with an embodiment of the invention. The modular antenna system is configured to provide Wireless Power Transmission (WPT) from a power transmitter to a receiver of the rechargeable vehicle.

[0055] Fig. 3A illustrates a top view of a modular basic antenna tile 100, according to an embodiment of the invention. The basic antenna tile 100 comprises an active region 101 at the center with an antenna element that transmits the power that to provide Wireless Power Transmission (WPT), upwardly. The active region is located essentially at the center of the modular antenna tile. A center tile 102 for laterally protecting the active region 101 by a base frame that surrounds the active region of the antenna. The center tile 102 is a high-density fiberboard, high-density plastics to obtain durability (that can withstand wear and tear during long term use) and is designed to operate at under strong high magnitude electro-magnetic fields. Four ramp segments 103 are attached to four corresponding edges of the center tile 102. Four corner ramp segments 104 fill the four corresponding gaps between adjacent ramp segments 103. Each ramp segments is made of a durable inclined metal base ramp tile that allows a robot to approach the antenna from any direction, without compromising robot's balance. This way, access to the center tile 102 is allowed only via climbing a circumferential ramp frame that is formed by all ramp segments. Fig. 3B illustrates a bottom view of the modular basic antenna tile 100, according to an embodiment of the invention. A plurality of via holes 105 are formed in the bottom face of the center tile 102, for inserting a corresponding plurality of screws, for allowing fastening all the layers of the basic antenna tile 100 together.

[0056] Figs. 4A-4D illustrate top and bottom views of the center tile 102, ramp segments 103 and 104 of the modular basic antenna tile 100, respectively, according to an embodiment of the invention. It can be seen that each segment has projections 106 that correspond to mating sockets 107 that are used to attach each segment to its adjacent segments. The integration between different segments is easy and at the same time reliable connection, such that the parts will remain fastened while being exposed to the robots' movement and heavy load transportation above the antennas.

[0057] Fig. 5 illustrates an antenna tile 100 comprises a stack of layers. The bottom layer 1001 is an electrically conductive Copper / Aluminum shield, for avoiding the leakage of strong electric fields at the bottom of the antenna tile 100 and to prevent energy losses and interference with other surrounding electrical system.

[0058] One or more (in this example, two) strip antennas 1002 (made, for example, of copper or aluminum), optionally supported by a honeycomb substrate 1003 (a honeycomb structured material that is produced using an array of hollow tubes or cells sandwiched between two solid walls), made of a thermoplastic polymer (any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling) bonded to the isolation conductive shield plate 1001. A high strength chemically resistant encapsulation layer 1004 optionally formed from a polypropylene homopolymer. The encapsulation layer 1004 overlays the strip antennas and the conductive shield plate. When choosing the material for layers 1004 and 1003 several electrical characteristics must be taken into consideration, such as the dielectric properties, the dissipation factor and thermal properties. Layer 1004 overlays the two strip antennas 1002 and the isolation shield plate 1001, to encapsulate the antenna strips. A top protective layer 1009 can be formed from a Compact Density Fiberboard (CDF - a board with the durability and strength that can withstand prolonged use without fraying) that overlays the encapsulation layer 1004. The isolation shield plate 1001 is configured to be bonded or mechanically mounted to the surface of the robot's work environment. The top protective layer 1009 overlays the encapsulation layer and is configured to support physical contact with wheels and / or feet, on which the robots move. A plurality of screws 1010 are used for fastening together all the layers of the basic antenna tile 100.

[0059] The antenna tiles are highly modular and can be tailored to various specific solutions. Antennas' length can be designed from 10s of centimeters up to several meters. The antennas can be shaped in a modular manner that fits various surfaces, such as curved surfaces or changing of angles. The antennas can also be adapted in width and can be formed as stripes in between wheels, or and as sloped ramps, on which the robot moves.

[0060] Figs. 6A-6C illustrate modular assembly of several antenna tiles to create or form desired antenna patterns, according to an embodiment of the invention.

[0061] Fig. 6A illustrates placing two antenna tiles in series in order to obtain a longer antenna series. In all cases, physical connection may be via male / female connectors, while maintaining galvanic connection between corresponding strip antennas 1002 of each antenna tile.

[0062] Fig. 6B illustrates placing two antenna tiles in parallel in order to obtain a wider longer antenna series. Fig. 6C illustrates placing two antenna tiles in 90° orientation with respect to each other, in order to obtain a bended antenna segment. To ensure that the antennas are not detached, they are equipped with spring loaders.

[0063] Fig. 7A illustrates another option for joining antennas together is by integrating a connection box with bridge terminals between antennas. Each antenna 1401a and 1401b has its own cables 1402 that are connected via a terminal box 1403 to maintain electrical continuity. The terminal box 1403 is integrated into a predesigned cavity such that the overall height of the antenna is not compromised, and compact volume factor is obtained. Bolt fasteners 1404 are used to connect between mating terminals, as shown in Fig. 7B.

[0064] Fig. 8 illustrates another embodiment where two transmitters 1501a and 1501b, each comprising a transmitter box 1502a, 1502b and an antenna 1503a, 1503b, are deployed next to each other. The antennas 1503a, 1503b are connected together, such that wiring between antennas and transmitter boxes is deployed in a shielded manner through one antenna tile to the following antenna tile. This allows using the same antenna structure for touting and area efficient deployment, while doubling the overall power transfer simultaneously without interfering with each other, while effectively expanding both the charging area and increasing the overall transmitted power.

[0065] The above examples and description have of course been provided only for the purpose of illustrations, and are not intended to limit the invention in any way. As will be appreciated by the skilled person, the invention can be carried out in a great variety of ways, employing more than one technique from those described above, all without exceeding the scope of the invention.

Claims

CLAIMS1. A modular antenna system for providing Wireless Power Transmission (WPT) from a power transmitter to a receiver of a rechargeable vehicle, moving in a working environment, comprising: a) a plurality of modular antenna tiles configured to be coupled together and mounted and on one or more surfaces of said work environment, at least one modular antenna tile of said plurality comprises: a.l) an active region, located essentially at the center of said modular antenna tile with an antenna element that provides Wireless Power Transmission (WPT) upwardly; a.2) a center tile for laterally protecting said active region using a base frame surrounding said active region; a.2) a circumferential ramp frame that is formed by ramp segments being coupled to corresponding edges of said center tile and corner ramp segments for filling corresponding gaps between adjacent ramp segments; a.2) a bottom layer being an electrically conductive shield plate, for avoiding the leakage of electric fields at the bottom of said active region; a.2) at least one strip antennas for Wireless Power Transmission (WPT) received from said power transmitter; a.2) an encapsulation layer overlaying said at least one strip antennas and said conductive shield plate, to encapsulate said strip antennas; a.2) a top protective layer, overlaying said encapsulation layer, for providing mechanical protection to said modular antenna tile; and b) at least one male connector and / or at least one female socket for receiving a male connector such that said antenna tile is mechanically connected to one or more adjacent antenna tiles to form a desired antenna pattern and maintain electrical contact between corresponding strip antennas of adjacent antenna tiles.

2. A modular antenna system according to claim 1, wherein the strip antenna within the active region is encapsulated by plastic-based materials having predetermined dielectric properties, dissipation factor and thermal properties.

3. A modular antenna system according to claim 1, wherein at least one modular antenna tile of the plurality of modular antenna tiles is a feeder tile, for coupling said modular antenna tile to an antenna driver that provides electrical power to be transmitted to the rechargeable vehicle.

4. A modular antenna system according to claim 2, wherein the feeder tile functions as a bridge tile for connecting two modular antenna tiles.

5. A modular antenna system according to claim 1, wherein at least one modular antenna tile of the plurality of modular antenna tiles is an isolation tiles that connects two modular antenna tiles mechanically but not electrically.

6. A modular antenna system according to claim 1, wherein at least one modular antenna tile of the plurality of modular antenna tiles is a gap tile being connected to a male connector or female socket of a modular antenna tile, for blocking said female socket form being used to connect between adjacent tiles.

7. A modular antenna system according to claim 1, wherein the desired antenna pattern forms:- a straight line antenna tile;- a right angle antenna tile;- an elbow antenna tile.

8. A modular antenna system according to claim 1, wherein the plurality of via holes are formed in the bottom face of the center tile, for inserting a corresponding plurality of screws, for allowing fastening all the layers together.

9. A modular antenna system according to claim 1, wherein modular antenna tiles are connected together by integrating a terminal connection box with bridge terminals between adjacent antenna tiles.

10. A modular antenna system according to claim 1, wherein the rechargeable vehicle is: a wheeled robot; a robot equipped with caterpillar tracks.

11. A modular antenna system according to claim 1, wherein antenna tiles are deployed directly on the floor of the working environment at positions past which rechargeable vehicles move.

12. A modular antenna system according to claim 1, wherein the thickness of the antenna tiles does not exceed 1 cm.

13. A modular antenna system according to claim 1, wherein the center tile is made of a high-density fiberboard or high-density plastics, for obtaining mechanical durability and being capable of operating under high magnitudes of electro-magnetic fields.

14. A modular antenna system according to claim 1, wherein each ramp segments is made of a durable inclined metal base ramp tile that allows a rechargeable vehicle to approach said antenna system from any direction, without compromising robot's balance.

15. A modular antenna system according to claim 1, wherein the strip antennas are supported by a honeycomb substrate made of foamed PVC (polyvinylchloride) or any other thermoplastic polymer substrate, bonded to the isolation conductive shield plate.

16. A modular antenna system according to claim 1, wherein the top protective layer is formed from a Compact Density Fiberboard (CDF), overlaying the encapsulation layer.

17. A modular antenna system according to claim 1, wherein the conductive shield plate is configured to be bonded or mechanically mounted to a surface of the work environment.

18. A modular antenna system according to claim 1, further comprising plurality of screws for fastening together all the layers.

19. A modular antenna system according to claim 1, in which at least one antenna tile comprises a stack of layers, sandwiched between the bottom baseplate layer and the top protective layer.

20. A modular antenna system according to claim 1, further comprising transmitter boxes with corresponding antenna tiles deployed next to each other, wherein said antenna tiles are connected together such that wiring between antennas and said transmitter boxes is deployed through one antenna tile to the adjacent antenna tile.

21. A modular antenna system according to claim 19, in which wiring is shielded.

22. A modular antenna system according to claim 1, further comprising spring loaders, for preventing detachment of tiles.

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