PATENT DOCUMENT

Publication Number: US-10418863-B1
Application Number: US-201816212411-A
Country: US
Kind Code: B1

Title: Charging system

Abstract:
A mobile charging device may be used to move a battery or a power cord to a target device. The target device may be a vehicle or other equipment with a battery. Power from the power cord or battery in the charging device may be used to provide power to the target device to recharge the battery in the target device. The charging device may couple a power cord to the target device, may couple a connector in the charging device to the target device, or may use a wireless power transfer element such as a coil antenna to transfer power wirelessly to the target device. Sensors may be used to facilitate alignment between the charging device and target device. Sensors may also be used to dynamically detect and avoid foreign objects in the path of the charging device.

Claims:
What is claimed is: 
     
       1. A device for providing power to a target device, comprising:
 a movement system; 
 a power cord; 
 wireless circuitry that is configured to gather wireless beacon signals; 
 control circuitry that is configured to direct the movement system to move the control circuitry and power cord along a path on a surface based at least partly on the wireless beacon signals to deliver power from the power cord to the target device; and 
 
       at least one sensor, wherein the control circuitry is configured to control the movement system to guide the control circuitry and power cord around foreign objects detected with the sensor. 
     
     
       2. The device defined in  claim 1  further comprising a wireless power transfer element that is configured to transfer power wirelessly from the power cord to the target device. 
     
     
       3. The device defined in  claim 2  wherein the wireless power transfer element comprises at least one coil that is configured to be inductively coupled to a wireless power transfer receiver in the target device. 
     
     
       4. The device defined in  claim 3  wherein the movement system comprises at least one motor and wheels and wherein the control circuitry is configure to control the at least one motor to rotate at least one of the wheels. 
     
     
       5. The device defined in  claim 1  further comprising a cord management system that is operable to retract and dispense the power cord under control of the control circuitry. 
     
     
       6. The device defined  claim 1  wherein the sensor comprises a sensor selected from the group consisting of: a radio-frequency signal sensor, a camera, a light detector, a temperature sensor, a motion sensor, a magnetic sensor, a touch sensor, a switch, a strain gauge, an accelerometer, and a microphone. 
     
     
       7. The device defined in  claim 1  further comprising:
 a wireless power transfer element; and 
 a positioner, wherein the control circuitry is configured to:
 control the positioner to align the wireless power transfer element with the target device; and 
 use the wireless power transfer element to wirelessly transfer power from the power cord to the target device through the aligned wireless power transfer element. 
 
 
     
     
       8. The device defined in  claim 7  further comprising at least one electrical component configured to supply signals to the control circuitry that the control circuitry uses to align the wireless power transfer element to the target device. 
     
     
       9. The device defined in  claim 8  wherein the component comprises a radio-frequency transceiver. 
     
     
       10. The device defined in  claim 8  wherein the component comprises a component selected from the group consisting of: a light detector and a light emitter. 
     
     
       11. The device defined in  claim 8  wherein the component comprises a component selected from the group consisting of: a camera and a magnetic sensor. 
     
     
       12. The device defined in  claim 7  further comprising a wireless communications device, wherein the control circuitry is configured to use the wireless communications device in aligning the wireless power transfer element to the target device. 
     
     
       13. The device defined in  claim 7  wherein the target device has an alignment structure, the charging device further comprising an alignment structure that is configured to mate with the alignment structure in the target device to align the wireless power transfer element to the target device. 
     
     
       14. The device defined in  claim 1  wherein the control circuitry is configured to use a cost function to determine a path for routing the power cord to the target device and wherein the cost function is used to determine the path based at least partly based on values assigned to different areas through which the power cord passes. 
     
     
       15. The device defined in  claim 1  wherein the target device comprises a vehicle with a wireless power receiver element and wherein the charging device further comprises a wireless power transfer element that is configured to wirelessly transfer power from the power cord to the wireless power receiver element in the vehicle. 
     
     
       16. A charging device operable to provide power to a target device, comprising:
 a positioning system with wheels; 
 a battery; 
 control circuitry that is configured to control the positioning system to move the battery to the target device with the wheels and deliver power wirelessly to the target device from the battery; and 
 
       sensors, wherein the control circuitry is configured to use the sensors to detect foreign objects as the battery is moved to the target device. 
     
     
       17. The charging device defined in  claim 16  further comprising a wireless power transfer element configured to wirelessly transfer the power from the battery to the target device, wherein the control circuitry is configured to use the sensors to align the wireless power transfer element to the target device. 
     
     
       18. The charging device defined in  claim 16  wherein the target device comprises a vehicle with a wireless power receiver element and wherein the charging device further comprises a wireless power transfer element that is configured to wirelessly transfer power from the battery to the wireless power receiver element in the vehicle. 
     
     
       19. A charging device operable to couple a power cord to a target device to provide power to the target device, comprising:
 wheels; 
 control circuitry configured to control the wheels to move the power cord to the target device; and 
 a positioner that is configured to mechanically couple the power cord to the target device to deliver power to the target device from the power cord. 
 
     
     
       20. The charging device defined in  claim 19  wherein the target device has a first connector, wherein the power cord has a second connector, and wherein the control circuitry is configured to direct the positioner to couple the first connector to the second connector to deliver power to the target device through the first and second connectors, further comprising a cord management system that is operable to retract and dispense the power cord under control of the control circuitry, further comprising sensors, wherein the control circuitry is configured to use the sensors to detect foreign objects as the power cord is moved to the target device, wherein the control circuitry is configured to determine a path for routing the power cord to the target device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. Non-Provisional patent application Ser. No. 15/265,359, filed Sep. 14, 2016, which claims the benefit of U.S. Provisional Patent Application No. 62/233,891, filed Sep. 28, 2015, each of which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     This relates generally to power transfer systems and, more particularly, to systems that transfer power to charge batteries. 
     It may be desirable to transfer power between a source of power and equipment that requires power. In some systems, a user must manually plug a power cable into equipment that requires power. In other systems, a user must align equipment to be powered with a wireless charging source. These types of systems can be cumbersome and inefficient. For example, systems may be prone to misalignment, operator error, and other concerns that can make it difficult or impossible to provide power as efficiently as desired. 
     It would therefore be desirable to be able to provide improved systems for transferring power to equipment that uses power. 
     SUMMARY 
     Mobile equipment such as a mobile robotic charging device may be used to move a battery or a power cord to a target device. The target device may be equipment with a battery. Power from the power cord or battery in the charging device may be used to provide power to the target device to recharge the battery in the target device. 
     The charging device may couple a power cord to the target device, may couple a connector in the charging device to the target device, or may use a wireless power transfer element such as a coil antenna to transfer power wirelessly to the target device. 
     Sensors and other components may be used to facilitate alignment between the charging device and target device. Sensors and other components may, for example, be used to align a power connector or wireless power transfer element to the target device. Sensors and other components may also be used to dynamically detect foreign objects in the path of the charging device, so that the charging device can take appropriate corrective action. 
     A cost function may be used in evaluating different potential routes for the path that charging device takes to the target device. The cost function may take into account that certain areas in the vicinity of the target device are prohibited or are preferred. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram of a target device that may consume power and a charging device for use in providing power to the target device in accordance with an embodiment. 
         FIG. 2  is a schematic diagram of an illustrative charging device in accordance with an embodiment. 
         FIGS. 3, 4, and 5  are diagrams of illustrative base stations for providing a charging device with a recharged battery in accordance with embodiments. 
         FIGS. 6 and 7  are diagrams of illustrative base stations for providing a charging device with corded power in accordance with an embodiment. 
         FIG. 8  is a side view of an illustrative charging device that is wirelessly transferring power from a battery in the charging device to a target device in accordance with an embodiment. 
         FIG. 9  is a side view of an illustrative charging device that is wirelessly transferring power to a target device using a power cord coupled to the charging device in accordance with an embodiment. 
         FIG. 10  is a side view of an illustrative charging device that is transferring power to a target device using a power cord coupled to the charging device and a wired connection between the charging device and a target device in accordance with an embodiment. 
         FIG. 11  is a side view of an illustrative charging device that has coupled a detachable cord to a target device to transfer power to the target device in accordance with an embodiment. 
         FIG. 12  is a diagram of an illustrative charging device that is using a sensor system to locate a target device in accordance with an embodiment. 
         FIG. 13  is a diagram of an illustrative charging device that is being directed towards a target device using predefined route information in accordance with an embodiment. 
         FIG. 14  is a diagram of an illustrative system environment in which a charging device is following a path to a target device in accordance with an embodiment. 
         FIGS. 15, 16, 17, 18, 19, and 20  show illustrative equipment that may be used in aligning a charging device and a target device in accordance with an embodiment. 
         FIG. 21  is a diagram showing how a charging device may dynamically avoid foreign objects in accordance with an embodiment. 
         FIG. 22  is a flow chart of illustrative steps involved in using a charging device with a battery to deliver power to a target device in accordance with an embodiment. 
         FIG. 23  is a flow chart of illustrative steps involved in using a charging device to assist in the delivery of power to a target device through a power cord in accordance with an embodiment. 
         FIG. 24  is a flow chart of illustrative steps involved in using a charging device to transfer power to a target device while performing alignment and foreign object avoidance operations in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     It may be desirable to use a computer-controlled mobile robot or other mobile equipment to provide power to target electronic equipment. The target equipment may be provided with power wirelessly or using a wired path and may sometimes be referred to as a target device. Power may be used to recharge a battery in the target device or to power other circuitry in the target device, so the mobile equipment may sometimes be referred to as a charging device or charging equipment. The target device may be a computer or other electronic device, may be an electric vehicle or other mobile electronic equipment, may be an appliance, may be lighting or other stationary electronic equipment, or may be any other suitable electronic equipment. Configurations in which the target device is an electric vehicle and in which power is provided to recharge a battery in the vehicle may sometimes be described herein as an example. 
     An illustrative system that includes a target device and a charging device for providing power to the target device is shown in  FIG. 1 . As shown in  FIG. 1 , target device  14  may be provided with power using a system such as system  12 . System  12  may include a mobile unit (robot) such as charging device  20  and a base station such as base station  16 . 
     Target device  14  (e.g., a vehicle, etc.) may contain a battery such as battery  34 . Target device  14  may also contain circuitry  32  for controlling the operation of target device  14 . For example, in scenarios in which target device  14  is an electric vehicle, control circuitry in circuitry  32  may be used in controlling functions such as steering, braking, acceleration and controlling other vehicle functions. Circuitry  32  may also include power circuitry for use in recharging battery  34 . The power circuitry may be used in delivering power from a wired source to battery  34  or may, as shown in  FIG. 1  be used in delivering power from a wireless component such as wireless power transfer element  30  to battery  34 . 
     Wireless power transfer element  30  (sometimes referred to as a wireless power transmitter element) may be wirelessly coupled to a corresponding wireless power transfer element (sometimes referred to as a wireless power receiver element) such as element  28  in equipment  20 . Wireless power may be transferred using inductive techniques, capacitively coupled capacitor plates, near-field coupled antennas operating at microwave frequencies or other frequencies, or other wireless power transfer techniques. With one illustrative configuration, which may sometimes be described herein as an example, wireless power transfer elements  28  and  30  are inductively coupled (near-field coupled) coils (e.g., loop antennas). Other types of wireless power transfer elements may be used, if desired. 
     Charging device  20  may include wheels  24  or other structures that allow charging device  20  to travel along a surface such as surface  36 . Surface  36  may be part of a garage, part of an outdoors roadway, or may be any other suitable path on which target device  14  and charging device  20  can travel. Motors in charging device  20  may be used to rotate and steer wheels  24  to move charging device  20  in a desired direction. 
     Computer-controlled motors or other actuators such as positioner  26  may be used in positioning structures within charging device  20 . For example, positioner  26  may be used in positioning wireless power transfer element  28 . Positioner  26  may position element  28  by tilting, raising and lowering, and/or rotating element  28 . In configurations in which charging device  20  includes a battery for transferring power to target device  14 , a battery loading and unloading device may be used to load and unload fresh batteries from a rack of available pre-charged batteries (as an example). A motor or other actuator may, if desired, be used to control cord management system  22  under control of control circuitry in charging device  20 . System  22  may have a motorized rotating reel or other equipment that can be used to retract power cord  18  into charging device  20  or to deploy power cord  18  onto surface  36  (i.e., by feeding cord  18  out of an opening in charging device  20 ). The motors or other electrically controlled components that rotate and steer wheels  24  and otherwise control the movement of charging device  10  may sometimes be referred to herein as the movement system of charging device  20 . Any suitable movement system may be used to control the movement of charging device  20  under the control of control circuitry within charging device  20  (e.g., a movement system based on electric drive motors for wheels  24  and a linear actuator coupled to a steering rack that turns wheels  24  in desired directions, etc.). 
     Base station  16  may be used as part of system  12 . With one illustrative configuration, base station  16  may be used to recharge a power transfer battery in charging device  20  or may be used to supply charging device  20  with a freshly charged battery from an array of batteries in base station  16  (e.g., batteries that are charged using wall outlet power in base station  16 ). With the configuration of  FIG. 1 , power is supplied from base station  16  to charging device  20  using a path such as power cord  18 . If desired, wired power transfer arrangements such as arrangements in which charging device  20  and target device  14  have mating connectors may be used in transferring power to equipment  14 . The use of wireless power transfer equipment (e.g., inductive power transfer equipment) such as wireless power transfer elements  38  and  30  is merely illustrative. 
     A schematic diagram of illustrative components that may be provided in charging device  20  is shown in  FIG. 2 . As shown in  FIG. 2 , charging device  20  may include control circuitry  38 . Control circuitry  38  may include microprocessors, memory (e.g., volatile and nonvolatile storage), application-specific integrated circuits, and other storage and processing circuitry. Code that is implemented on control circuitry  38  may be used in controlling the motion of charging device  20 , aligning wireless power transfer element  38  with external equipment, processing sensor data and other inputs to avoid foreign objects, controlling wireless and/or wired charging operations and/or other power transfer operations, and in performing other functions associated with the operation of charging device  20 . 
     Input-output devices  40  may be used in gathering input from a user and/or making measurements on the environment surrounding charging device  20  and/or may be used in supplying output to a user and/or equipment in the vicinity of charging device  20 . Control circuitry  38  may process the information obtained by input-output devices  40  and may provide input-output devices  40  with output. 
     As shown in  FIG. 2 , input-output devices  40  may include user input-output devices  50 . Devices  50  may include buttons, touch sensors, track pads, keyboards, and other components for receiving input from a user. Sensors  42  may be used in controlling the motion of charging device  20 , performing alignment operations, avoiding foreign objects, and/or receiving user input. Sensors  42  may include light-based sensors for detecting ambient light, light-based proximity sensors for detecting objects in the vicinity of charging device  20 , magnetic sensors, temperature sensors, accelerometers and other position and/or motion sensors, acoustic sensors, gas sensors, humidity sensors, cameras (e.g., visible, infrared, and/or ultraviolet image sensors), compasses, and other sensors. Audio components  44  may include speakers and other components for producing audio output, acoustic sensors such as microphones for gathering input from a user (e.g., voice commands) and/or for measuring ambient sounds. Displays  46  may include touch screens and/or displays that are insensitive to touch. Light-emitting diodes, lamps, lasers, and other light-emitting devices  48  may be used to provide a user with output and/or may be used as part of a sensor system (e.g., a system that identifies the location of charging device  20  and/or other objects). Wireless communications circuitry  58  may be used to transmit and/or receive radio-frequency wireless signals (e.g., Bluetooth® signals, WiFi® signals, other wireless signals, etc.), light-based wireless signals, and/or other wireless signals. Data may also be communicated over wired paths. Wireless power transfer circuitry  60  may include wireless power transfer element  28  (e.g., a coil, etc.) for use in wirelessly transmitting power from charging device  20  to target equipment  14 . 
     Charging device  20  may have motors such as motors  52  for steering and rotating wheels  24  ( FIG. 1 ) and thereby moving charging device  20  in a desired direction. Positioners  54  (see, e.g., positioner  26  for positioning wireless power transfer element  28 ) may adjust an arm or other movable member that is used in positioning other element  28  or for otherwise moving structures associated with charging device  20 . A loading and unloading device (e.g., a motorized rack, etc.) may, for example, be used in loading and unloading batteries into charging device  20 . A motorized spool may be used in controlling the position of cord  18  (e.g., when plugging a plug on the end of cord  18  into a mating receptacle in equipment  14 ). Cord management system  22  may, for example, include a powered retractable reel (see, e.g.,  FIG. 1 ) or other equipment for retracting and dispensing cord  18 . Battery  56  may include one or more batteries for providing charging device  20  with backup power (e.g., backup power for powering charging device  20  during the process of loading and unloading energy transfer batteries) and/or for storing energy that is to be transferred from charging device  20  to equipment  14  (wirelessly or via a wired connection). The operation of equipment such as motors  52 , positioners  54 , cord management system  22 , circuitry for controlling battery  56 , input-output devices  40 , wireless communications circuitry  58 , and power transfer circuitry  60  may be controlled using control circuitry  38 . If desired, other electrical components may be provided in charging device  20  and/or one or more of the components of  FIG. 2  may be omitted. The configuration of  FIG. 2  is merely illustrative. 
     Base stations such as base station  16  may be provided in locations that are close to parking spaces (e.g., in home garages, in public garages and parking lots, etc.) or other locations in the vicinity of equipment in need of receiving power. Base stations  16  may receive wall outlet power at any suitable voltage and may transfer this power to equipment  12  wirelessly, using a wired connection, by shuttling power via a battery, etc. 
     Illustrative arrangements for using batteries to provide power to equipment  12  (e.g., charging device  20 ) from base station  16  are shown in  FIGS. 3, 4, and 5 . 
     In the example of  FIG. 3 , base station  16  has a power source such as power source  64 . Power source  64  may be a wall outlet that mates with a corresponding connector such as connector  66  in charging device  20 . Using this arrangement, mains power can be transferred to charging device  20  to charge internal battery  56 . Once battery  56  has been charged, charging device  20  can be moved in alignment with equipment  14 , so that the energy from battery  56  can be transferred to battery  34  of equipment  14  wirelessly or via a wired connection (see, e.g., power transfer element  28 ). 
     In the example of  FIG. 4 , base station  16  has a power source such as power source  70 . Power source  70  of  FIG. 4  may be a wall outlet with wireless power transfer circuitry that transfers power wirelessly to wireless power reception equipment  72  in charging device  20 . Using this arrangement, wall power can be transferred to charging device  20  to charge internal battery  56 . Charging device  20  can then be moved in alignment with target device  14 , so that the energy from battery  56  can be transferred to battery  34  of target device  14  wirelessly or via a wired connection. 
     With the illustrative arrangement of  FIG. 5 , circuits  74  may contain a source of power such as a wall outlet and associated battery charging circuitry to charge a bank of spare batteries  56 . Charging device  20  can be moved into alignment with target device  14  and the battery  56  within charging device  20  can be used to charge battery  34  in target device  14  via wired or wireless charging. Once battery  56  in charging device  20  has been depleted, charging device  20  can return to base station  16  and can swap the depleted battery for one of the freshly charged batteries  56  in base station  16 . Positioners  54  of charging device  20  ( FIG. 2 ) or computer-controlled positioners associated with base station  16  may be used to swap batteries. 
       FIGS. 6 and 7  show illustrative arrangements in which charging device  20  may use a power cord such as power cord  18  in transferring power to battery  34  of equipment  14 . 
     In the example of  FIG. 6 , cord  18  is coupled to a power source such as wall outlet  76 . Wall outlet  76  can provide power to cord  18 . Cord management system  22  may be used to retract and deploy cord  18  as charging device  20  moves relative to base station  16  and equipment  14 . When aligned with target device  14 , charging device  20  can transfer power from cord  18  to target device  14  wirelessly (via element  28 ) or via a wired connection. 
     In the illustrative configuration of  FIG. 7 , cord  18  is coupled to a power source such as wall outlet  76  that provides power to cord  18 . Charging device  20  of  FIG. 7  may include a cord management system (see, e.g., cord management system  22  of  FIG. 2 ) that is used to retract and deploy cord  18  as charging device  20  moves relative to base station  16  and equipment  14 . Charging device  20  may also have a positioner such as positioner  54  that is used in placing plug (connector)  78  of cord  18  into a mating receptacle (connector) in target device  14  when charging device  20  is adjacent to target device  14 . After coupling the connector on power cord  18  with a connector in target device  14 , positioner  54  may release cord  18  from charging device  20  (i.e., cord  18  of  FIG. 7  may be a releasable cord that is not permanently attached to charging device  20 ). With an arrangement of the type shown in  FIG. 7 , a single piece of equipment such as charging device  20  may be used to couple multiple power cords to respective pieces of equipment such as multiple target devices  14 . 
     When aligned with target device  14 , charging device  20  can transfer power from cord  18  to target device  14  wirelessly (via element  28 ) or via a wired connection.  FIGS. 8, 9, 10, and 11  show illustrative power transfer scenarios in which charging device  20  and the power transfer components of charging device  20  have been aligned with corresponding power transfer components in target device  20 . In these illustrative scenarios, charging device  20  is moved under the body of target device  14  (e.g., charging device  20  may be moved under the body of a vehicle in scenarios in which target device  14  is a vehicle). This helps ensure that charging device  20  will not be visible and/or will not intrude on the movement of people or items in the vicinity of target device  14 . Other arrangements for placing charging device  20  adjacent to target device  14  during power transfer operations may be used, if desired. 
     In the illustrative configuration of  FIG. 8 , charging device  20  has been moved under target device  20  so that wireless power transfer element  28  is aligned with wireless power transfer element  30  of equipment  14 . Charging device  20  may align element  28  with element  30  using wheels  24  and/or positioner  26 . Once aligned, power can be wirelessly transferred from battery  56  in charging device  20  to target device  14 . 
     In the arrangement of  FIG. 9 , power cord  18  may be used to supply charging device  20  with power, so battery  56  may be omitted (or may be retained for use as a backup battery). After aligning wireless power transfer element  28  with element  30  of target device  14  using wheels  24  and/or positioner  26  (e.g., using positioner  26  to tilt, rotate, and/or shift the position of element  28  to align with element  30 ), charging device  20  may wirelessly transfer power that has been received from a wall outlet in base station  16  via cord  18  to target device  14 . 
     A wired power transfer approach is illustrated in  FIG. 10 . In the scenario of  FIG. 10 , charging device  20  receives power from base station  16  via power cord  18 . Charging device  20  may use wheels  24  and/or positioner  26  to align and mate connector  82  of charging device  20  with corresponding connector  80  of equipment  14 . Connectors  80  and  82  may include power plug and receptacle structures that allow power to be transferred using a wired connection between charging device  20  and target device  14 . With the illustrative configuration of  FIG. 10 , charging device  20  may remain adjacent to target device  14  during power transfer operations. 
     In the illustrative arrangement of  FIG. 11 , power cord  18  is detachable and need not remain affixed to charging device  20 . As shown in  FIG. 11 , for example, charging device  20  may move away from equipment  14  in direction  86  after positioner  54  of charging device  20  aligns connector  78  with mating connector  84  of equipment  14  and couples connector  78  of power cord  18  with mating connector  84 . Charging device  20  may be used to couple numerous power cords to the connectors of multiple pieces of equipment such as multiple target devices  14  and need not remain in the vicinity of any particular target device  14  during charging. 
     It may be desirable for charging device  20  and/or target device  14  to include components that help guide charging device  20  to target device  14 . As shown in  FIG. 12 , target device  14  may include a beacon such as beacon  88 . Beacon  88  or an array of beacons  88  may be mounted on target device  14  (e.g., on a vehicle), may be mounted in a parking space in which target device  14  is located, or may be placed at other suitable locations in the vicinity of device  14 . Each beacon  88  may emit wireless signals  90  that are detected by sensors in equipment  90 . Wireless signals  90  may include radio-frequency signals, light, acoustic signals (sound) or other wireless signals. Using triangulation techniques, by analyzing received signal strength information, and/or using other techniques, charging device  20  can determine an appropriate path such as path  92  to follow when moving charging device  20  towards target device  14 . For example, control circuitry in device  20  may be configured to gather emitted wireless beacon signals from multiple beacons in the vicinity of device  20  and to determine path  92  using triangulation based on the gathered wireless beacon signals. 
     If desired, target device  14  and/or other equipment in system  10  may be used in formulating a request for receiving power from charging device  20 . The request may be generated by charging device  20  or other equipment (e.g., equipment in base station  16  or elsewhere in a parking lot or other facility containing base station  16 ) in response to detection of target device  14  and, if desired, in response to additional criteria such as information on whether battery  34  in equipment  14  is in need of charging. For example, target device  14  may obtain information on its location within a parking lot by reading a bar code, by using pattern recognition techniques to identify a parking space number, by using radio-frequency identification (RFID) techniques to determine a parking space number or other location information, by using non-light-based sensors such as magnetic sensors, acoustic sensors, or other sensors to obtain location information, or by using other sensors in target device  14  and/or elsewhere in system  10  to determine the location of target device  14 . A user of target device  14  may, if desired, by prompted to supply location information for target device  14  (e.g., by entering a voice command through a voice recognition interface in target device  14 , by manually typing or otherwise inputting location information into target device  14  or equipment in system  10  that is external to target device  14 , etc.). Information on the presence and location of target device  14  may also be gathered using parking space sensors (magnetic sensors, radio-frequency identification readers, light-based sensors, cameras, acoustic sensors, etc.) or sensors elsewhere in a parking lot or other facility. 
     Based on information gathered by target device  14 , information supplied by a user, information gathered using sensors in a parking lot or other facility, information gathered by charging device  20 , and/or information supplied and/or gathered using other equipment in system  10 , a request for receiving power from charging device  20  can be formulated. This request may be transmitted to charging device  20  via wired and/or wireless connections and may include information on the location of target device  14  and other information (battery charge state, request priority, financial information for payment of fees associated with receiving power, etc.). In response to receiving the request, charging device  20  may determine an appropriate path for equipment  20  and may move charging device  20  to target device  14  along this path. 
     An illustrative request-based scenario for moving charging device  20  towards target device  14  is illustrated in  FIG. 13 . In the example of  FIG. 13 , target device  14  is a vehicle in a parking lot that includes three parking spaces PS 1 , PS 2 , and PS 3 . Charging device  20  has been provided with information (e.g., position information in dimensions X and Y) on the location of each parking space and the areas surrounding the parking spaces. In the  FIG. 13  example, vehicle  14  has parked in parking space PS 2  and a request for receiving power from equipment  20  has been provided to charging device  20 . Based in knowledge of the location of vehicle  14  and the current location of charging device  20  (e.g., in base station  16 ), charging device  20  can identify an appropriate route for path  92  and can travel along path  92  to vehicle  14 . 
     In determining appropriate paths to follow, charging device  20  may take into account the nature of the various areas surrounding target device  14 . Consider, as an example, a parking lot environment of the type shown in  FIG. 14 . As shown in  FIG. 14 , parking lot  94  may contain a parking space area such as parking space area  98 . Parking space area  98  may contain parking spaces such as parking spaces PSA, PSB, PSC, PSD, PSE, and PSF. Vehicles can be parked in these parking spaces. In the example of  FIG. 14 , vehicles have been parked in parking spaces PSC and PSD and target vehicle  14  has been parked in parking space PSE. 
     Some areas of parking lot  94  such as area  96  are active vehicle paths and are not available for use by charging device  20 . Other areas such as border area  100  are optimal for travel by charging device  20 . Areas such as area  100  of  FIG. 14  may, for example, be blocked to traffic using a traffic barrier. Pedestrians may also be prohibited from entering area  100  (e.g., using signs and/or fences). Charging device  20  may be allowed to travel in other portions of parking lot  96  such as parking space area  98 , but may wish to do so only in limited circumstances (e.g., to avoid interfering with people entering and exiting vehicles, to avoid laying power cords where people may desire to walk, etc.). In determining an optimal route for path  92  between base station  16  and target device  14 , charging device  20  may take into account the level of desirability (e.g., the “cost”) associated with traveling in each of multiple different areas in parking lot  94 . With this type of approach, prohibited areas may be associated with high (e.g., infinite) cost, desired area  100  may be provided with a zero cost or other low cost, and intermediate areas such as area  98  may be provided with correspondingly intermediate levels of cost. Using a cost function (e.g., a function that can be evaluated to minimize the “cost” associated with traveling through various areas), charging device  20  can determine an optimal route for path  92 . 
     In some scenarios, fixed and/or moving obstacles may interfere with the movement of charging device  20 . For example, a foreign object such as foreign object  102  may be present or may become present in parking lot  94  during movement of charging device  20 . In situations in which foreign object  102  is present and detectable by the sensors of charging device  20  or other equipment in system  10  before path  94  is determined, foreign object  102  can be avoided in advance (e.g., by providing the area occupied by object  102  with a high cost value in a cost function during route planning operations). In other situations, such as scenarios in which foreign object  102  moves into a planned path for charging device  20  while charging device  20  is actively moving towards target device  14 , foreign object avoidance techniques may be used to ensure that charging device  20  does not collide with foreign object  102 . 
     In the example of  FIG. 14 , path  92  avoids foreign object  102 , maximizes use of optimal travel area  100 , avoids use of forbidden travel area  96 , and minimizes use of parking space area  98 . Other routes for paths such as path  92  of  FIG. 14  may be used, if desired. Moreover, parking lots and other areas may be provided with any suitable number of different areas each having a respective cost value (e.g., parking lot  94  may be divided into two or more zones, three or more zones, ten or more zones, hundreds of zones, or any other suitable number of zones each of which has a potentially different level of “path cost” associated with an optimal path determination cost function). The use of a parking lot with three different levels of permissibility for travel by charging device  20  in the example of  FIG. 14  is merely illustrative. 
     Once charging device  20  is adjacent to target device  14  (e.g., when charging device  20  is located under a wireless or wired charging port in a vehicle or other target device  14 ), charging device  20  may use sensors and other equipment to help align power transfer components in devices  20  and  14 . Alignment operations may be performed using sensors, mechanical interlock features, and other alignment equipment. 
       FIGS. 15, 16, 17, 18, 19, and 20  are diagrams of illustrative structures and components that may be used by charging device  20  in performing alignment operations. In the examples of  FIGS. 15, 16, 17, 18, 19, and 20 , part of the alignment equipment has been implemented in equipment  104  and a corresponding part of the alignment equipment has been implemented in equipment  106 . Equipment  104  may form part of charging device  20  and equipment  106  may form part of target device  14 , equipment  106  may form part of charging device  20  and equipment  104  may form part of target device  14 , or target device  14  and charging device  20  may each include equipment such as equipment  104  and  106 . 
     In the example of  FIG. 15 , equipment  104  has a transceiver such as radio-frequency transmitter  108 . Radio-frequency transmitter  108  may emit wireless signals  110  (e.g., beacon signals, etc.) at any suitable frequency. A corresponding transceiver such as radio-frequency receiver  112  in equipment  106  can detect the location and strength of signals  110  and can use these signals to help align equipment  104  and  106  (e.g., using triangulation techniques, received signal strength measurements, etc.). Receiver  112  may include one or more antennas (e.g., antennas located at suitably spaced locations to provide enhanced resolution to the radio-frequency signal alignment process). 
       FIG. 16  is a diagram of an illustrative light-based system. In the  FIG. 16  arrangement, equipment  104  includes a light source such as light source  114 . Light source  114  may emit light  116  at any suitable wavelength (infrared, visible, and/or ultraviolet) and may include one or more lasers, light-emitting diodes, lamps, or other light emitting components. Light detector  118  may include one or more photodetectors, cameras, or other components that measure the direction, strength, and other attributes of light  116  to help align equipment  104  to equipment  106 . 
     In the scenario of  FIG. 17 , equipment  104  has a visual marker such as maker  120 . Light source  122  may emit light  124  that illuminates marker  120  and that is reflected towards equipment  106  as reflected light  126  and  130 . Light  126  may be detected using light detector  128  in equipment  106  (e.g., one or more photodiodes, etc.). Light  130  may be detected using alight sensing component such as camera  132  (e.g., one or more digital image sensors in equipment  106 ). By processing the signals gathered by light detector  128  and/or camera  132 , equipment  106  can determine the location of marker  120  and thereby align equipment  104  to equipment  104 . Marker  120  may include a black-and-white target or other high contrast target, a bar code, a color-coded area, alignment fiducials, and/or other encoded visual information. Light may also be reflected off of structures in equipment  104  other than marker  120  to help in alignment operations. 
       FIG. 18  shows how physical alignment features may be used to assist in alignment operations. Structure  134  in equipment  104  may have an alignment structure such as recess  136  and structure  140  in equipment  106  may have a mating alignment structure such as protrusion  138 . Grooves, recesses, angled surfaces and/or other features may be used to help promote insertion of alignment feature  138  into alignment feature  136 . When coupled together, the physical alignment structures of  FIG. 18  may help ensure that equipment  104  and  106  has been properly aligned. 
     In the arrangement of  FIG. 19 , equipment  106  includes wireless power transmission circuitry  142  that wirelessly transmits wireless power signals  144  to corresponding wireless power receiver circuitry  146  in equipment  104 . When wireless power transmitter  142  and wireless power receiver  146  are well aligned, power will be transferred efficiently. When transmitter  142  and receiver  146  are misaligned, power transfer efficiency will drop. Equipment  104  may evaluate the quality of power transfer from transmitter  142  to receiver  146  and can provide corresponding wireless feedback information to equipment  106 . For example, information indicating how well equipment  104  and  106  are aligned may be transmitted wirelessly from equipment  104  to equipment  106  using wireless communications transceiver circuitry  148  (e.g., a wireless transmitter) to transmit wireless communications signals  150  to wireless communications transceiver circuitry  152  (e.g., a wireless receiver). If desired, bidirectional communications may be used in conveying information about power transfer efficiency and alignment. 
     Magnetic alignment equipment may also be used to help align equipment  104  and equipment  106 . As shown in  FIG. 20 , for example, equipment  104  may have one or more magnets such as magnet  154  that emit magnetic fields  156 . Equipment  106  may contain one or more magnetic sensors such as sensor  158  for detecting magnetic fields  156 . Equipment  104  and  106  may be aligned by aligning sensor  158  relative to magnet  154 . 
     If desired, one or more alignment components of the type shown in  FIGS. 15, 16, 17, 18, 19, and 20  may be used together to improve alignment efficiency and/or accuracy and these components may be used in conjunction with other alignment components. The alignment components of  FIGS. 15, 16, 17, 18, 19, and 20  are merely illustrative. 
     Charging device  20  may include components to help avoid contact between charging device  20  and foreign objects. For example, charging device  20  may include foreign object detection sensors to perform real-time foreign object detection operations. If a foreign object is detected in the intended path of charging device  20 , charging device  20  can update the path to avoid the foreign object. As shown in  FIG. 21 , for example, charging device  20  may be moving towards target equipment  14  along a path such as path  92 - 1 . While moving along path  92 - 1 , foreign object  102  may move into a position that overlaps path  92 - 1 . Sensors  42  may be used to detect the presence of foreign object  102 . When object  102  is detected, charging device  20  can determine and follow an updated path such as path  92 - 2  towards object  14 . 
     Sensors  42  may detect foreign objects using lasers or other light emitters and light sensors (e.g., lidar, etc.), may detect foreign objects using ultrasonic position sensors and other acoustic object detection sensors, may detect sensors using radio-frequency signals (e.g., radar, etc.), may detect sensors using cameras and other light detectors (e.g., light detectors that detect ambient light and/or emitted light from charging device  20 , camera-based motion sensors and other light-based motion sensors that evaluate light signals to detect motion, infrared cameras and other infrared detectors for detecting objects such as living things that emit heat, cameras that detect objects using pattern recognition processes, etc.), may include temperature sensors, magnetic sensors (e.g., for detecting ferromagnetic foreign objects), touch sensors, mechanical sensors such as switches that close when coming into physical contact with foreign object  102 , strain gauges for detecting contact with external objects, accelerometers that detect deceleration of equipment  20  due to contact with object  102 , microphones that detect changes in ambient noise levels when charging device  20  comes into close proximity to object  102 , or other equipment for detecting the presence of objects such as object  102 . 
     Illustrative steps involved in using charging device  20  to transfer energy from a power source in a location such as base station  16  to target device  14  are shown in  FIG. 22 . At step  160 , charging device  20  may receive a fresh battery  56  from base station  16  as described in connection with  FIG. 5  or may receive wired power ( FIG. 3 ) or wireless power ( FIG. 4 ) to recharge battery  56  in charging device  20 . After ensuring that battery  56  in equipment  160  is charged, charging device  20  may be moved to the vicinity of target device  14  (step  162 ). In particular, charging device  20  may use a cost function analysis to determine a desired path  92  to target device  14  and/or may select from one or more predefined satisfactory paths  92  to follow to target device  14 . Foreign objects may be avoided by using sensors in charging device  20 , as described in connection with  FIG. 21 . At step  164 , the energy from battery  56  in charging device  20  may be transferred to battery  34  in target device  14 . Power may be transferred to battery  34  using a wired connection (e.g., mating connectors in devices  20  and  14 ) or wirelessly, as described in connection with  FIG. 8 . 
     Illustrative steps involved in providing power to target device  14  using power cord  18  are shown in  FIG. 23 . At step  166 , charging device  20  and power cord  18  may be moved to target device  14 . Charging device  20  may follow an optimum path (e.g., path  92 ) in moving to target device  14  and may use cord management system  22  to dispense cord  18  along path  92 . Foreign objects may be avoided by using sensors in charging device  20 , as described in connection with  FIG. 21 . At step  168 , charging device  20  may form a wired connection with target device  14  as described in connection  FIG. 14 , may form a wireless power transfer link with target device  14 , as described in connection with  FIG. 9 , or may attach plug  78  on a detachable power cord to a corresponding connector in target device  14 , as described in connection with  FIG. 11 . At step  170 , power cord  18  may provide power to target device  14  to recharge battery  34 . 
     Illustrative steps involved in moving charging device  20  along an optimal path to target device  14  while avoiding foreign objects and performing alignment operations to facilitate power transfer are shown in  FIG. 24 . At step  172 , a request from target device  14 , sensor data, or other information may be received by charging device  20  to initiate power transfer operations. At step  174 , charging device  20  may use a cost function or other arrangement to determine an optimal path such as path  92 . In determining which path is optimal, charging device  20  can take account of which travel areas are prohibited (e.g., areas occupied by physical obstructions, areas frequented by vehicle traffic, etc.), which areas are preferred (e.g., safe out-of-the way areas), and which areas are permissible when necessary (e.g., areas around vehicles, etc.). Control circuitry  38  may be used in determining the route for path  92  using the cost function. At step  182 , control circuitry  38  may control motors  52  for wheels, steering, and/or other motion control equipment in charging device  20  so that charging device  20  travels to target device  14  along path  92 . In the event that a foreign object is detected along path  92 , charging device  20  can compute an updated path (e.g., path  92 - 2  of  FIG. 21 ) to avoid the foreign object, may stop all motion of charging device  20 , may issue an error message or other message for a user (e.g., a wireless message such as a text message or other wireless alert, an email message, an audible message such as a warning tone or verbal message, etc.), may request manual intervention, or may take other suitable actions before computing another path to equipment  14  at step  174 . 
     When target device  14  has been reached by charging device  20 , alignment operations may be performed to align connectors and/or wireless power transfer elements in charging device  20  and target device  14 . Alignment techniques of the type described in connection with  FIGS. 15, 16, 17, 18, 19, and 20  and/or other suitable alignment techniques may be used during the alignment operations of step  176 . At step  178 , power can be transferred from a power cord or battery in charging device  20  to target device  14 . 
     The operations of  FIGS. 22, 23, and 24  may be performed by control circuitry  38  in device  20  (system  12 ) and/or control circuitry  32  in device  14 . During operation, this control circuitry (which may sometimes be referred to as processing circuitry, processing and storage, computing equipment, a computer, etc.) may be configured to perform the methods of  FIGS. 22, 23, and 24  (e.g., using dedicated hardware and/or using software code running on hardware in devices  20  and/or  14 ). The software code for performing these methods, which may sometimes be referred to as program instructions, code, data, instructions, or software, may be stored on non-transitory (tangible) computer readable storage media in control circuitry  38  and/or  32  in devices  20  and/or  14  such as read-only memory, random-access memory, hard drive storage, flash drive storage, removable storage medium, or other computer-readable media and may be executed on processing circuitry such as microprocessors and/or application-specific integrated circuits with processing circuits in control circuitry  38  and/or  32 . 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20181206
Publication Date: 20190917
Grant Date: 20190917
Priority Date: 20150928
Inventors: JADIDIAN, Jouya
CABRAL, STEVEN W.
PATHAK, VANEET
Assignee: APPLE INC
CPC Classifications: [{"code": "H02J7/0042", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/60", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J50/90", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/60", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/90", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J50/60", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/025", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0042", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J50/90", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 67908932