PATENT DOCUMENT

Publication Number: US-11177693-B1
Application Number: US-201916556125-A
Country: US
Kind Code: B1

Title: Wearable loops with embedded circuitry

Abstract:
An electronic device such as a loop-shaped wearable electronic device may have a fabric cord with first and second opposing ends and a housing unit coupled between the first and second ends. The housing unit may contain circuitry such as a visual output region, sensors, communications circuitry, and wireless power receiving circuitry. The wearable electronic device may include haptic output devices for providing haptic output for a user or for changing the shape of the fabric cord. The fabric cord may include a conductive strand that forms a coil for receiving wireless power signals from a wireless power transmitter. The wearable electronic device may be stored in a charging case that includes wireless power transmitting circuitry for powering the wearable electronic device. Control circuitry in the charging case may change an opacity of the charging case based on a charging status of the wearable electronic device.

Claims:
What is claimed is: 
     
       1. A loop-shaped wearable electronic device configured to be worn on a body part of a user, comprising:
 a fabric cord having first and second ends; 
 a housing unit coupled between the first and second ends; 
 sensors that gather sensor data; 
 a haptic output device; and 
 control circuitry in the housing unit that provides haptic output using the haptic output device based on the sensor data. 
 
     
     
       2. The loop-shaped wearable electronic device defined in  claim 1  wherein the haptic output device is configured to change a shape of the fabric cord from a furled shape to an unfurled shape. 
     
     
       3. The loop-shaped wearable electronic device defined in  claim 2  wherein the haptic output device comprises piezoelectric fibers. 
     
     
       4. The loop-shaped wearable electronic device defined in  claim 2  wherein the haptic output device comprises magnetic structures. 
     
     
       5. The loop-shaped wearable electronic device defined in  claim 1  further comprising a visual output region on the housing unit. 
     
     
       6. The loop-shaped wearable electronic device defined in  claim 5  further comprising a magnetic clasp that allows the loop-shaped wearable electronic device to be opened and closed. 
     
     
       7. The loop-shaped wearable electronic device defined in  claim 6  wherein the sensors comprise a magnetic sensor that detects whether the loop-shaped wearable electronic device is open or closed. 
     
     
       8. The loop-shaped wearable electronic device defined in  claim 7  wherein the control circuitry provides visual output using the visual output region in response to receiving a signal from the magnetic sensor that the loop-shaped wearable electronic device is closed. 
     
     
       9. The loop-shaped wearable electronic device defined in  claim 5  wherein the visual output region comprises a status indicator light-emitting diode. 
     
     
       10. The loop-shaped wearable electronic device defined in  claim 5  wherein the visual output region comprises an array of pixels and wherein the pixels are selected from the group consisting of: liquid crystal pixels, light-emitting diode pixels, organic light-emitting diode pixels, and Janus particle pixels. 
     
     
       11. The loop-shaped wearable electronic device defined in  claim 1  further comprising wireless power receiving circuitry that receives wireless power for the sensors, wherein the fabric cord comprises at least one conductive strand that forms a coil and wherein the wireless power receiving circuitry receives the wireless power using the coil. 
     
     
       12. The loop-shaped wearable electronic device defined in  claim 1  further comprising:
 a motion sensor that gathers motion data; and 
 wireless communications circuitry that transmits the motion data to an external electronic device. 
 
     
     
       13. A loop-shaped wearable electronic device configured to be placed on an object or a person, comprising:
 a fabric cord having first and second ends; 
 a housing unit coupled between the first and second ends; 
 a removable structure with additional circuitry that is configured to be coupled to the housing unit; 
 a motion sensor that gathers motion data; 
 wireless communications circuitry configured to wirelessly transmit the motion data to the electrical equipment; and 
 wireless power receiving circuitry configured to receive wireless power for the motion sensor. 
 
     
     
       14. The loop-shaped wearable electronic device defined in  claim 13  wherein the fabric cord comprises at least one conductive strand that forms a coil and wherein the wireless power receiving circuitry is configured to receive the wireless power using the coil. 
     
     
       15. The loop-shaped wearable electronic device defined in  claim 13  wherein the wireless power receiving circuitry is configured to receive the wireless power from a transmitter that is separated from the loop-shaped wearable electronic device by a given distance. 
     
     
       16. A loop-shaped wearable electronic device configured to be placed on an object or a person, comprising:
 a fabric cord having first and second ends; 
 a housing unit coupled between the first and second ends; 
 a motion sensor that gathers motion data; 
 wireless communications circuitry configured to wirelessly transmit the motion data to the electrical equipment; and 
 wireless power receiving circuitry configured to receive wireless power for the motion sensor, wherein the fabric cord is configured to be inserted through a ring-shaped structure having additional circuitry. 
 
     
     
       17. A charging case for a loop-shaped wearable electronic device, comprising:
 an upper housing having a recess; 
 a lower housing configured to be coupled to the upper housing; 
 a column extending from the lower housing that extends into the recess of the upper housing when the lower housing is coupled to the upper housing, wherein the column is configured to receive the loop-shaped wearable electronic device; and 
 wireless power transmitting circuitry that transmits wireless power signals to the loop-shaped wearable electronic device when the loop-shaped wearable electronic device is received on the column. 
 
     
     
       18. A charging case for a loop-shaped wearable electronic device, comprising:
 an upper housing; 
 a lower housing; 
 a column extending from the lower housing, wherein the column is configured to receive the loop-shaped wearable electronic device; 
 wireless power transmitting circuitry that transmits wireless power signals to the loop-shaped wearable electronic device when the loop-shaped wearable electronic device is received on the column; and 
 control circuitry, wherein the upper housing has a portion with adjustable opacity, and wherein the control circuitry adjusts the opacity of the portion based on a charging status of the loop-shaped wearable electronic device. 
 
     
     
       19. The charging case defined in  claim 17  further comprising wireless power receiving circuitry that receives wireless power from a wireless power transmitter in a charging mat. 
     
     
       20. The charging case defined in  claim 17  further comprising a microphone for receiving voice input commands and a speaker for responding to the voice input commands with audio output.

Description:
This application claims the benefit of provisional patent application No. 62/728,304, filed Sep. 7, 2018, which is hereby incorporated by reference herein in its entirety. 
    
    
     FIELD 
     This relates generally to electronic devices and, more particularly, to wearable devices. 
     BACKGROUND 
     Electronic devices may include input-output components such as sensors and light-emitting components. It can be challenging to incorporate components such as these into a wearable device. If care is not taken, the wearable device will be overly fragile, bulky, or unattractive. 
     SUMMARY 
     An electronic device such as a loop-shaped wearable electronic device may have a fabric cord and a housing unit. The housing unit may contain circuitry such as a visual output region, sensors, communications circuitry, and wireless power receiving circuitry. The visual output region may include a status indicator or a display. The wearable electronic device may include haptic output devices for providing haptic output for a user or for changing the shape of the fabric cord. The haptic output devices may include piezoelectric fibers that form part of the fabric cord or may include magnetic structures. The haptic output devices may cause the fabric cord to change from a furled shape to an unfurled shape. The fabric may include one or more conductive strands that form a coil. The coil may be used to receive wireless power signals from a wireless power transmitter. 
     The wearable electronic device may be stored in a charging case that includes wireless power transmitting circuitry for powering the wearable electronic device. The charging case may include upper and lower housings and a column extending from the lower housing. The wearable electronic devices may be received on the column. Control circuitry in the charging case may change an opacity of the charging case based on a charging status of the wearable electronic device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram of an illustrative system including a loop-shaped wearable electronic device in accordance with an embodiment. 
         FIG. 2  is a perspective view of an illustrative loop-shaped wearable electronic device having a fabric cord and a housing unit in accordance with an embodiment. 
         FIG. 3  is a perspective view of an illustrative loop-shaped wearable electronic device in an open state in accordance with an embodiment. 
         FIG. 4  is a cross-sectional side view of illustrative fabric that may be used in a loop-shaped wearable electronic device in accordance with an embodiment. 
         FIG. 5  is a perspective view of an illustrative loop-shaped wearable electronic device that has been inserted through an object such as a key in accordance with an embodiment. 
         FIG. 6  is a perspective view of an illustrative loop-shaped wearable electronic device that has been hung on an object such as a door knob in accordance with an embodiment. 
         FIG. 7  is a perspective view of illustrative loop-shaped wearable electronic devices that are interlocked with one another in accordance with an embodiment. 
         FIG. 8  is a perspective view of illustrative loop-shaped wearable electronic devices that have been connected end-to-end in accordance with an embodiment. 
         FIG. 9  is a perspective view of an illustrative loop-shaped wearable electronic device that is worn around a user&#39;s neck in accordance with an embodiment. 
         FIG. 10  is a perspective view of illustrative loop-shaped wearable electronic devices that are worn around a user&#39;s wrist in accordance with an embodiment. 
         FIG. 11  is a perspective view of an illustrative loop-shaped wearable electronic device in which circuitry is embedded entirely in a fabric cord in accordance with an embodiment. 
         FIG. 12  is a perspective view of an illustrative loop-shaped wearable electronic device in which a fabric cord has two ends connected to a housing unit in accordance with an embodiment. 
         FIG. 13  is a perspective view of an illustrative loop-shaped wearable electronic device in which a fabric cord has one end connected to a housing unit and one end detached from the housing unit in accordance with an embodiment. 
         FIG. 14  is a perspective view of an illustrative loop-shaped wearable electronic device in which a fabric cord has two ends with a housing unit at each end in accordance with an embodiment. 
         FIG. 15  is a perspective view of an illustrative loop-shaped wearable electronic device in which a fabric cord has two ends with one end attached to a housing unit and an opposing end with an engagement feature that mates with a corresponding engagement feature in the housing unit in accordance with an embodiment. 
         FIG. 16  is a perspective view of the loop-shaped wearable electronic device of  FIG. 15  showing how a fabric cord may engage with a housing unit in accordance with an embodiment. 
         FIG. 17  is a perspective view of an illustrative loop-shaped wearable electronic device having a fabric cord that is inserted through openings in add-on structures in accordance with an embodiment. 
         FIG. 18  is a perspective view of an illustrative loop-shaped wearable electronic device having add-on structures inserted between portions of a housing unit in accordance with an embodiment. 
         FIG. 19  is a perspective view of an illustrative loop-shaped wearable electronic device having a housing unit with a status indicator in accordance with an embodiment. 
         FIG. 20  is a perspective view of an illustrative loop-shaped wearable electronic device having a housing unit without a display or status indicator in accordance with an embodiment. 
         FIG. 21  is a perspective view of an illustrative loop-shaped wearable electronic device having a housing unit with a display that covers a portion of the housing unit in accordance with an embodiment. 
         FIG. 22  is a perspective view of an illustrative loop-shaped wearable electronic device having a housing unit with a display that covers all of the housing unit in accordance with an embodiment. 
         FIG. 23  is a perspective view of an illustrative charging case that may be used to charge loop-shaped wearable electronic devices in accordance with an embodiment. 
         FIG. 24  is a perspective view of an illustrative charging case having a column on which loop-shaped wearable electronic devices have been placed in accordance with an embodiment. 
         FIG. 25  is a side view of an illustrative charging case having a transparent portion in accordance with an embodiment. 
         FIG. 26  is a side view of an illustrative charging case having an opaque portion in accordance with an embodiment. 
         FIG. 27  is a top view of an illustrative charging mat that is used to wirelessly charge a charging case and loop-shaped wearable electronic devices in accordance with an embodiment. 
         FIG. 28  is a diagram illustrating how a loop-shaped wearable electronic device may be used to track a motion path of a person, animal, or object that is wearing the loop-shaped wearable electronic device in accordance with an embodiment. 
         FIG. 29  is a perspective view of illustrative wrist-watch device displaying relative locations of nearby loop-shaped wearable electronic devices in accordance with an embodiment. 
         FIG. 30  is a perspective view of an illustrative electronic device displaying locations and orientations of nearby loop-shaped wearable electronic devices in accordance with an embodiment. 
         FIG. 31  is a diagram of an illustrative system including a loop-shaped wearable electronic device with markers that are tracked using a camera in an external electronic device in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may be worn on a user&#39;s body or may be attached to an object. For example, an electronic device may have a loop, band, or string-like shape that can be looped around, tied to, hung on, or otherwise attached to a person, animal, or object. Electronic devices may be worn on a user&#39;s wrist or neck, may be looped through an object such as a key, pet collar, or suitcase, or may be otherwise attached to a person or object. Electronic devices that can be attached to a person, animal, or object, which are sometimes referred to as loop-shaped wearable electronic devices, string devices, or string-like electronic devices, may be used to gather information about the person or object that the electronic device is attached to (e.g., location information, activity information, identification information, medical or biometric information, etc.), may be used to gather user input (e.g., touch input, force input, motion input, and/or voice input), may be used to provide a user with output (haptic output, audio output, and/or visual output), may be used to store identification information about the person or object that the string device is attached to, may be used to store messages for a user, may be used as an anchor or visual marker in an augmented reality or virtual reality system, and/or may be used for other functions. 
       FIG. 1  is a schematic diagram of an illustrative system of the type that may include one or more string devices. As shown in  FIG. 1 , system  8  may include electronic device(s) such as loop-shaped wearable electronic device  10  and other electronic device(s)  40 . Each electronic device  10  may be worn on a person (e.g., a person&#39;s wrist, arm, finger, arm, neck, waist, ankle, or other suitable body part), may be worn on an animal (e.g., cat, dog, etc.), or may be coupled to an object (e.g., a suitcase, key fob, a door knob, an electronic device, or any other suitable object). Additional electronic devices in system  8  such as devices  40  may include devices such as a laptop computer, a computer monitor containing an embedded computer, a tablet computer, a desktop computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wristwatch device, a pendant device, a headphone or earpiece device, a head-mounted device such as glasses, goggles, a helmet, or other equipment worn on a user&#39;s head, or other wearable or miniature device, a television, a computer display that does not contain an embedded computer, a gaming device, a remote control, a navigation device, an embedded system such as a system in which equipment is mounted in a kiosk, in an automobile, airplane, or other vehicle, a removable external case for electronic equipment, a strap, a wrist band or head band, a removable cover for a device, a case or bag that has straps or that has other structures to receive and carry electronic equipment and other items, a necklace or arm band, a wallet, sleeve, pocket, or other structure into which electronic equipment or other items may be inserted, part of a chair, sofa, or other seating (e.g., cushions or other seating structures), part of an item of clothing or other wearable item (e.g., a hat, belt, wrist band, headband, sock, glove, shirt, pants, etc.), or equipment that implements the functionality of two or more of these devices. 
     With one illustrative configuration, which may sometimes be described herein as an example, device  10  is a string-like wearable electronic device worn by a person, animal, or object and may be configured as a loop shape (e.g., a continuous loop of string without any end points or a loop of string formed from joining first and second opposing ends of the string) and/or a non-loop shape (e.g., a string having first and second opposing ends that are not joined), and electronic device  40  is a cellular telephone, tablet computer, laptop computer, wristwatch device, head-mounted device, a device with a speaker, or other electronic device (e.g., a device with a display, audio components, and/or other output components). 
     Device  10  may include control circuitry  12 . Control circuitry  12  may include storage and processing circuitry for supporting the operation of device  10  and/or system  8 . The storage and processing circuitry may include storage such as hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in control circuitry  12  may be used to control the operation of device  10 . The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio chips, application specific integrated circuits, etc. 
     To support interactions with external equipment, control circuitry  12  may be used in implementing communications protocols. Communications protocols that may be implemented using control circuitry  12  include internet protocols, wireless local area network protocols (e.g., IEEE 802.11 protocols—sometimes referred to as WiFi®), protocols for other short-range wireless communications links such as the Bluetooth® protocol, cellular telephone protocols, MIMO protocols, antenna diversity protocols, satellite navigation system protocols, millimeter wave communications protocols, IEEE 802.15.4 ultra-wideband communications protocols, etc. 
     Device  10  of system  8  may include input-output devices  14 . Input-output devices  14  may be used in gathering user input, gathering information on the environment surrounding device  10 , and/or providing a user with output. Input-output devices  14  of device  10  may include light-emitting components. For example, input-output devices  14  can include devices such as a display and/or other light sources  16 . Light sources  16  may include one or more individual light-emitting devices such as light-emitting diode(s), laser(s), and/or lamp(s). Light sources  16  may include status indicator lights (e.g., a light-emitting diode that serves as a power indicator, and other light-based output devices) and/or may include arrays of pixels for forming displays such as liquid crystal displays, organic light-emitting diode displays, electrophoretic displays, displays formed from Janus particles, displays formed from crystalline semiconductor dies (microLEDs), etc. 
     Input-output devices  14  of device  10  may include input components  18  such as buttons, touch sensors (e.g., capacitive touch sensors, optical touch sensors, etc.), force sensors, and/or other devices for receiving input such as button press input and/or touch or force sensor input. 
     Sensors  20  of device  10  may be used in gathering environmental measurements and/or user input and may include ambient light sensors (visible light sensors, color sensitive light sensors, ultraviolet light sensors, etc.), optical proximity sensors, capacitive proximity sensors, temperature sensors, force sensors (e.g., strain gauges, capacitive force sensors, resistive force sensors, force sensors for measuring biometric information, etc.), audio sensors such as microphones, magnetic sensors (e.g., Hall effect sensors, giant magnetoresistance sensors, or other sensors or magnetometers that measure magnetic fields), gas pressure sensors, heart rate sensors, blood oxygen level sensors (e.g., based on emitted and detected light), electrocardiogram sensors (e.g., sensors for measuring electrical signals on a user&#39;s body), humidity sensors, moisture sensors, particulate sensors (e.g., sensors that use light measurements and/or other measurements to measure particulate concentration in the air), image sensors (cameras), gas pressure sensors, carbon dioxide sensors and/or sensors measuring other gas concentrations, sensors for detecting position, orientation, and/or motion (e.g., accelerometers, magnetic sensors such as compass sensors, gyroscopes, barometers, and/or inertial measurement units that contain some or all of these sensors), radio-frequency sensors, depth sensors (e.g., structured light sensors and/or depth sensors based on stereo imaging devices), optical sensors such as self-mixing sensors and light detection and ranging (lidar) sensors that gather time-of-flight measurements, accelerometers for gathering user tap input, and/or other sensors. In some arrangements, device  10  may use sensors  20  and/or other input-output devices  14  to gather user input (e.g., buttons may be used to gather button press input, touch sensors overlapping displays can be used for gathering user touch screen input, touch pads may be used in gathering touch input, microphones may be used for gathering audio input, accelerometers may be used in monitoring when a finger contacts an input surface and may therefore be used to gather finger press input, etc.). Sensors  20  may include sensing electrodes, which may be formed from conductive strands of material in fabric such as fabric  36  (e.g., sensor electrode pads may be formed from fabric), may be formed from metal traces on printed circuits, and/or may be formed from other sense electrode structures. 
     If desired, input-output devices  14  may include one or more speakers and one or more microphones for providing device  10  with virtual assistant functionality for a user of device  10 . For example, microphones in device  10  may receive voice input commands and speakers in device  10  may supply audible responses to the voice input commands. 
     Haptic output devices  22  may include piezoelectric devices, electromagnetic actuators, and/or other actuators for generating haptic output. Haptic output devices  22  can produce motion that is sensed by the user (e.g., through the user&#39;s skin). Haptic output devices  22  may include actuators such as electromagnetic actuators, motors, piezoelectric actuators, electroactive polymer actuators, vibrators, linear actuators, rotational actuators, actuators that bend bendable members, shape memory materials, actuator devices that create and/or control repulsive and/or attractive forces between devices  10  and/or  40  (e.g., components for creating electrostatic repulsion and/or attraction such as electrodes, components for producing ultrasonic output such as ultrasonic transducers, components for producing magnetic interactions such as electromagnets for producing direct-current and/or alternating-current magnetic fields, permanent magnets, magnetic materials such as iron or ferrite, and/or other circuitry for producing repulsive and/or attractive forces between devices  10  and/or  40 ). In some situations, actuators for creating forces in device  10  may be used in producing tactile output on the user&#39;s skin. For example, haptic output devices  22  may tighten or otherwise adjust the shape of the string-like device to provide haptic feedback to a user. In other situations, these components may be used to interact with each other (e.g., by creating a dynamically adjustable electromagnetic repulsion and/or attraction force between a pair of devices  10  and/or between device(s)  10  and device(s)  40  using electromagnets). 
     In one illustrative arrangement, haptic output devices  22  include piezoelectric actuators formed from piezoelectric fibers in fabric  36 . For example, fabric  36  may be a nonwoven fabric that contains polyvinylidene fluoride (PVDF) fibers that have been aligned to exhibit piezoelectricity. The fibers may be deposited using a hollow cylindrical near-field electrospinning process or other process. This type of fabric, sometimes referred to as PVDF nonwoven fiber fabric, may be used as an energy harvester, an electromechanical actuator, and/or a pressure sensor. If desired, control circuitry  12  may provide haptic output or may change the shape of device  10  using PVDF nonwoven fabric. 
     If desired, haptic output devices  22  may include magnetic structures such as magnetic linkages that furl and unfurl under an appropriate electromagnetic field. This type of haptic output device may be used to provide haptic output to a user and/or to change the shape of device  10 . 
     Device  10  may include one or more energy storage devices  24 . Energy storage devices  24  may include batteries and capacitors. Capacitors for energy storage may be based on supercapacitor structures. Devices  24  may, for example, include super capacitor(s) such as electrostatic double-layer capacitors. Electrostatic double-layer capacitors (sometimes referred to as electrostatic double-layer supercapacitors) are electrochemical capacitors in which energy is stored in a capacitor formed from relatively large electrodes that are bathed in electrolyte and separated by a small distance, allowing the capacitor to achieve high energy storage capacities. 
     Energy storage device  24  may be charged via a wired connection or, if desired, device  10  may charge energy storage device  24  using wirelessly received power. Power may be received wirelessly using wireless power receiving circuitry  32 . Wireless power receiving circuitry  32  in device  10  may receive power from wireless power transmitting circuitry. The wireless power transmitting circuitry may be located in device  40  or other electronic device. The wireless power transmitting circuitry may transmit power wirelessly using inductive wireless power transfer, using capacitive wireless power transfer, and/or other wireless power transfer configurations (e.g., optical). 
     With one illustrative configuration, wireless power receiving circuitry  32  may include, for example, inductive charging components such as coil  34  and a corresponding rectifier circuit or other wireless power receiving circuit for converting wirelessly received power from coil  34  into direct-current power for powering device  10  and charging energy storage device  24 . 
     As another example, wireless power receiving circuitry  32  may be configured to convert radio-frequency energy received by antenna  28  from a radio-frequency transmitter into direct-current power for powering device  10  and charging battery  24 . The radio-frequency transmitter may be located in device  40  or other electronic device and may, if desired, be located a given distance away from device  10  (e.g., the radio-frequency transmitter need not be directly near to device  10  for receiving circuitry  32  to be able to convert the radio-frequency energy into direct-current power). 
     If desired, ambient light can be converted into direct-current power for device  10  using photovoltaic device (solar cells). Energy can also be harvested from movements of the user of device  10  (e.g., using a piezoelectric energy harvesting device or other energy harvesting circuitry). 
     Control circuitry  12  may use communications circuitry  26  to transmit data to external equipment and to receive data from external equipment. Communications circuitry  26  may include wireless communication circuitry such as one or more antennas such as antenna  28  and associated radio-frequency transceiver circuitry  30 . Transceiver circuitry  30  may include wireless local area network transceiver circuitry (e.g., WiFi® circuitry), Bluetooth® circuitry, cellular telephone transceiver circuitry, ultra-wideband communications transceiver circuitry, millimeter wave transceiver circuitry, near-field communications circuitry, satellite navigation system circuitry such as Global Positioning System (GPS) receiver circuitry (e.g., for receiving GPS signals at 1575 MHz or for handling other satellite positioning data), and/or wireless circuitry that transmits and/or receives signals using light (e.g., with light-emitting diodes, lasers, or other light sources and corresponding light detectors such as photodetectors). Antennas  28  may include monopole antennas, dipole antennas, patch antennas, inverted-F antennas, loop antennas, slot antennas, other antennas, and/or antennas that include antenna resonating elements of more than one type (e.g., hybrid slot-inverted-F antennas, etc.). Antennas  28  may be formed from metal traces on printed circuits or other substrates, may include stamped metal parts, may include metal structures that form part of an enclosure or other supporting structure for device  10 , may include wires and other conductive strands of material in fabric  36 , and/or other conductive structures. 
     Device  10  may use communications circuitry  26  to communicate directly with device  40 , to communicate with a server, and/or to communicate with other devices  10  in system  8 . If desired, multiple devices  10  may be used to form nodes in a mesh network. In this type of scenario, a given device  10  may communicate with device  40  and/or other devices  10  by routing signals through a mesh network of intermediary devices  10 . 
     Device  10  may include intertwined strands of material that form fabric such as fabric  36 . Fabric  36  may, if desired, be stretchable fabric (e.g., elastic fabric formed using stretchable strands of material). Items such as device  10  may therefore sometimes be referred to as fabric-based items, stretchable-fabric items, stretchable-fabric-based electronic devices, etc. In some configurations, stretchable fabric for device  10  may form a stretchable cord (e.g., a stretchable string) or a stretchable band (e.g., a wristband, headband, armband, waistband, other stretchable band in an item of clothing, or a stretchable band that is not used as an item of clothing). Fabric  36  of device  10  may be soft (e.g., fabric  36  may yield to a light touch), may have a rigid feel (e.g., fabric  36  may be a stiff fabric), may be coarse, may be smooth, may have ribs or other patterned textures, and/or may be formed as part of a device that has portions formed from non-fabric structures of plastic, metal, glass, crystalline materials, ceramics, or other materials. 
     Yarns for fabric  36  may be formed from polymer, metal, glass, graphite, ceramic, natural materials as cotton or bamboo, or other organic and/or inorganic materials and combinations of these materials. Conductive coatings such as metal coatings may be formed on non-conductive material. For example, plastic yarns and monofilaments may be coated with metal to make them conductive. Reflective coatings such as metal coatings may be applied to make yarns and monofilaments reflective. Yarns may be formed from a bundle of bare metal wires or metal wire intertwined with insulating monofilaments (as examples). Strands of fabric  36  may have the same color or there may be strands of two or more different colors in fabric  36 , if desired. 
     Strands of material may be intertwined to form fabric  36  using intertwining equipment such as weaving equipment, knitting equipment, or braiding equipment. Intertwined strands may, for example, form woven fabric, knit fabric, braided fabric, etc. Conductive strands and insulating strands may be woven, knit, braided, or otherwise intertwined to form contact pads that can be electrically coupled to conductive structures in item  10  such as the contact pads of an electrical component. The contacts of an electrical component may also be directly coupled to an exposed metal segment along the length of a conductive yarn or monofilament. 
     Conductive and insulating strands may also be woven, knit, or otherwise intertwined to form conductive paths. The conductive paths may be used in forming signal paths (e.g., signal buses, power lines, etc.), may be used in forming antennas, may be used in forming part of a capacitive touch sensor electrode, a resistive touch sensor electrode, a force sensor electrode, or other input-output device, or may be used in forming other patterned conductive structures. Conductive structures in the fabric of item  10  may be used in carrying power signals, digital signals, analog signals, sensor signals, control signals, data, input signals, output signals, radio-frequency signals such as antenna signals, or other suitable electrical signals. 
     Device  10  may include mechanical structures in addition to fabric  36  such as polymer binder to hold strands in fabric  36  together, support structures such as frame members, housing structures (e.g., an electronic device housing), and other mechanical structures. 
     Electronic device  40  of system  8  may include control circuitry  42 . Control circuitry  42  may include storage and processing circuitry for supporting the operation of device  40  and/or system  8 . The storage and processing circuitry may include storage such as nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in control circuitry  42  may be used to gather input from sensors and other input devices and may be used to control output devices. The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors and other wireless communications circuits, power management units, audio chips, application specific integrated circuits, etc. 
     Electronic device  40  may include input-output devices  46 . Input-output devices  46  may be used in gathering user input, in gathering information on the environment surrounding device  40 , and/or in providing a user with output. Devices  46  may include sensors  48 . Sensors  48  may include force sensors (e.g., strain gauges, capacitive force sensors, resistive force sensors, etc.), audio sensors such as microphones, touch and/or proximity sensors such as capacitive sensors, optical sensors such as optical sensors that emit and detect light, ultrasonic sensors, and/or other touch sensors and/or proximity sensors, monochromatic and color ambient light sensors, image sensors, sensors for detecting position, orientation, and/or motion (e.g., accelerometers, magnetic sensors such as compass sensors, gyroscopes, and/or inertial measurement units that contain some or all of these sensors), muscle activity sensors (EMG), radio-frequency sensors, depth sensors (e.g., structured light sensors and/or depth sensors based on stereo imaging devices), optical sensors such as self-mixing sensors and light detection and ranging (lidar) sensors that gather time-of-flight measurements, humidity sensors, moisture sensors, and/or other sensors. In some arrangements, device  40  may use sensors  48  and/or other input-output devices  46  to gather user input (e.g., buttons may be used to gather button press input, touch sensors overlapping displays can be used for gathering user touch screen input, touch pads may be used in gathering touch input, microphones may be used for gathering audio input, accelerometers may be used in monitoring when a finger contacts an input surface and may therefore be used to gather finger press input, etc.). 
     Device  40  may include haptic output devices  50 . Haptic output devices  50  can produce motion that is sensed by the user (e.g., through the user&#39;s skin). Haptic output devices  50  may include actuators such as electromagnetic actuators, motors, piezoelectric actuators, electroactive polymer actuators, vibrators, linear actuators, rotational actuators, actuators that bend bendable members, actuator devices that create and/or control repulsive and/or attractive forces between devices  10  and/or  40  (e.g., components for creating electrostatic repulsion and/or attraction such as electrodes, components for producing ultrasonic output such as ultrasonic transducers, components for producing magnetic interactions such as electromagnets for producing direct-current and/or alternating-current magnetic fields, permanent magnets, magnetic materials such as iron or ferrite, and/or other circuitry for producing repulsive and/or attractive forces between devices  10  and/or  40 ). In some situations, actuators for creating forces in device  40  may be used in producing tactile output on the user&#39;s skin. In other situations, these components may be used to interact with each other (e.g., by creating a dynamically adjustable electromagnetic repulsion and/or attraction force between a pair of devices  40  and/or between device(s)  10  and device(s)  40  using electromagnets). 
     If desired, input-output devices  46  of device  40  may include other devices  52  such as displays (e.g., to display images for a user), status indicator lights (e.g., a light-emitting diode that serves as a power indicator, and other light-based output devices), speakers and other audio output devices, electromagnets, permanent magnets, structures formed from magnetic material (e.g., iron bars or other ferromagnetic members that are attracted to magnets such as electromagnets and/or permanent magnets), batteries, etc. Device  40  may also include power transmitting and/or receiving circuits configured to transmit and/or receive wired and/or wireless power signals. 
     To support communications between devices  10  and  40  and/or to support communications between equipment in system  8  and external electronic equipment, control circuitry  42  may communicate using communications circuitry  44 . Circuitry  44  may include antennas, radio-frequency transceiver circuitry, and other wireless communications circuitry and/or wired communications circuitry. Circuitry  44 , which may sometimes be referred to as control circuitry and/or control and communications circuitry, may, for example, support bidirectional wireless communications between devices  10  and  40  over wireless link  38  (e.g., a wireless local area network link, a near-field communications link, or other suitable wired or wireless communications link (e.g., a Bluetooth® link, a WiFi® link, a 60 GHz link or other millimeter wave link, an ultra-wideband communications link, etc.). Device  40  may also include power circuits for transmitting and/or receiving wired and/or wireless power and may include batteries. In configurations in which wireless power transfer is supported between devices  10  and  40 , in-band wireless communications may be supported using inductive power transfer coils (as an example). 
     Wireless signals  38  may be used to convey information such as location and orientation information. For example, control circuitry  42  in device  40  may determine the location of device  10  using wireless signals  38  and/or control circuitry  12  in device  10  may determine the location of device  40  using wireless signals  38 . 
     In one illustrative arrangement, device  10  may include a low-power transmitter (e.g., an radio-frequency identification transmitter or other transmitter). Device  40  may have a corresponding receiver that detects the transmitted signals  38  from device  10  and determines the location of device  10  based on the received signals. In some arrangements, device  10  may not include an internal power source and may instead be powered by electromagnetic energy from device  40  or other device. In other arrangements, device  10  may include an internal power source. 
     Device  40  may track the location (e.g., the indoor or outdoor location) of device  10  using signal strength measurement schemes (e.g., measuring the signal strength of radio signals from device  10 ) or using time based measurement schemes such as time of flight measurement techniques, time difference of arrival measurement techniques, angle of arrival measurement techniques, triangulation methods, time-of-flight methods, using a crowdsourced location database, and other suitable measurement techniques. This type of location tracking may be achieved using ultra-wideband signals, Bluetooth® signals, WiFi® signals, millimeter wave signals, or other suitable signals. This is merely illustrative, however. If desired, control circuitry  42  of device  10  may determine the distance to device  10  using Global Positioning System receiver circuitry, using proximity sensors (e.g., infrared proximity sensors or other proximity sensors), depth sensors (e.g., structured light depth sensors that emit beams of light in a grid, a random dot array, or other pattern, and that have image sensors that generate depth maps based on the resulting spots of light produced on target objects), sensors that gather three-dimensional depth information using a pair of stereoscopic image sensors, lidar (light detection and ranging) sensors, radar sensors, using image data from a camera, using motion sensor data, and/or using other circuitry in device  40 . 
     If desired, angle of arrival measurement techniques may be employed by control circuitry  12  of device  10  and/or control circuitry  42  of device  40  to determine the relative orientation of device  10  and device  40 . For example, control circuitry  42  may determine the orientation of device  40  relative to device  10  by determining a phase difference associated with signals  38  received by antennas in device  40 . The phase difference may be used to determine an angle of arrival of signals  38  received by device  40 . Similarly, control circuitry  12  of device  10  may, if desired, determine the orientation of device  10  relative to device  40  by determining a phase difference associated with signals  38  received by antennas  28  in device  10 . The phase difference may be used to determine an angle of arrival of signals  38  received by device  10 . 
     In some arrangements, one or more devices  10  may serve as an anchor or visual marker in a virtual reality or augmented reality system. When device  10  is used as an anchor, device  40  may map out an environment (or may receive and/or store information about a previously mapped out environment) using a virtual coordinate system that is anchored by device  40 . Device  40  may determine the location of other objects (e.g., other devices  10 ) based on the location of anchored device  10 . 
     In arrangements where device  10  is used as a visual marker, device  10  may include one or more features (e.g., physical surfaces features, infrared-reflective ink features, visible ink features, etc.) that may be detected by a camera in device  40  (e.g., an infrared camera, a visible light camera, or other suitable camera). The markers on device  10  may help inform system  8  of a location a virtual work surface and/or the location of a user&#39;s hands or other bod party as the user is interacting with a computer or other equipment in system  8 . 
     In some arrangements, devices  10  may be distributed at museums or events to provide guests with assistance. For example, devices  10  may be distributed with a pair of wireless headphones at a museum. Device  10  may store information about objects at the museum and may wirelessly transmit audio signals to the headphones to provide the user with audio describing the objects at the museum. Devices  10  may be used at events to give guests access to certain locations or content. These examples are merely illustrative. Devices  10  may be used for other purposes, if desired. 
       FIG. 2  is a perspective view of an illustrative electronic device  10 . Device  10  of  FIG. 2  may include components such as main housing unit  54  and/or cord  56 . Cord  56  and/or main unit  54  may each be configured to operate as a stand-alone unit, if desired. Illustrative configurations for device  10  in which device  10  includes cord  56  (e.g., a removable strap for main unit  54 , a strap that is integrated with main unit  54 , a stand-alone cord without an associated main unit  54 , etc.) may sometimes be described herein as examples. In general, device  10  may include any suitable structures (e.g., different types of wearable housings, etc.) that incorporate circuitry of the type shown in  FIG. 1 . Cord  56 , which may sometimes be referred to as a band or string, may be coupled to main unit  54  using magnets, pins, a tongue-and-groove configuration, using housing slits or other openings that receive cord  56 , and/or other configurations in which cord  56  is attached to main unit  54 . 
     Main housing unit  54 , which may sometimes be referred to as a case or housing capsule, may be formed from metal, polymer, ceramic, glass, silicone, leather, fabric, other suitable materials, or a combination of these materials. Main housing unit  54  may have any suitable shape. As examples, main housing unit  54  may have a circular cross-sectional shape, a rectangular cross-sectional shape, a rectangular cross-sectional shape with rounded corners, an oval cross-sectional shape, or other suitable cross-sectional shape. Main housing unit  54  and/or cord  56  may be formed using molding (e.g., injection molding, insert molding, overmolding, compression molding, etc.), machining, stretching, bending, casting, other fabrication techniques, or a combination of these fabrication techniques. 
     If desired, one or more portions of device  10  may be formed from fabric (e.g., fabric  36  of  FIG. 1 ). For example, cord  56  may be a cord of fabric or may include a cord of fabric (e.g., stretchable or non-stretchable fabric). Cord  56  of device  10  of  FIG. 2  is formed from a ring-shaped strip or cord of stretchable fabric having an opening that is configured to receive an object and/or a body part of a user. The loop shape of device  10  of  FIG. 2  allows device  10  to be worn on a body part of a user (e.g., a user&#39;s head, arm, wrist, waist, leg, ankle, finger, neck, torso, etc.). If desired, device  10  may be formed using stretchable fabric that returns to its original shape after being stretched. The use of stretchable fabric in device  10  may ensure that device  10  is held against the user&#39;s body so that sensors (e.g., sensor electrodes) will be in close proximity to the user&#39;s skin and can gather measurements that might otherwise be difficult or impossible to gather (e.g., skin moisture measurements, EKG measurements, blood pressure measurements, etc.). This is, however, merely illustrative. If desired, device  10  may be formed using fabric that is not stretchable or may be formed without fabric. 
     Cord  56  may have any suitable shape. As examples, cord  56  may have a circular cross-sectional shape, a rectangular cross-sectional shape, a rectangular cross-sectional shape with rounded corners, an oval cross-sectional shape, or other suitable cross-sectional shape. Cord  56  may have curved outer surfaces, may have planar outer surface, may be flat, or may have a combination of these shapes. 
     Cord  56  may be a single unitary cord (e.g., a continuous loop or a string having ends that attach to respective edges of main unit  54  and/or that attach to each other) or may be formed from first and second portions that can be joined by clasp  102  (e.g., a magnetic clasp, an electrical clasp, a mechanical clasp, etc.). If desired, device  10  may also or instead include a clasp in main unit  54  such as clasp  60  (e.g., a magnetic clasp, an electrical clasp, a mechanical clasp, etc.). 
     Cord  56  may be formed from elastomeric polymer (e.g., silicone and/or other stretchable plastics), may be formed from metal (e.g., metal links, interlinked chain links, etc.), may be formed from fabric (e.g., fabric  36  such as knit fabric, woven fabric, and/or braided fabric, fabric that includes stretchable strands of elastomeric material, etc.), may be formed from other materials (e.g., leather, wood, or other natural materials, ceramic, crystalline materials, etc.), and/or may be formed from a combination of these materials. Configurations in which cord  56  is formed from elastomeric polymer materials may sometimes be described herein as an example. This is, however, merely illustrative. Cord  56  may, in general, be formed from any suitable materials. Arrangements in which cord  56  and/or housing unit  54  include waterproof materials, water-resistant materials, and/or oil-resistant materials may also be used. 
     Clasp  102  and/or clasp  60  may be formed from any suitable clasp structure. If desired, clasp  102  and/or clasp  60  may be magnetic clasps (e.g., magnetic twist clasps). With this type of arrangement, portions of device  10  on opposing sides of clasp  102  and/or clasp  60  may be magnetically attracted to each other and may therefore close clasp  102  and/or clasp  60 . Device  10  may be pulled open at clasp  102  and/or clasp  60  (e.g., by applying sufficient force to overcome the magnetic attraction between these portions) whenever a user desires to open device  10 . When it is desired to close device  10  into a loop, the portions of device  10  on opposing sides of claps  102  and/or clasp  60  may be brought into close proximity to each other, at which point the magnetic attraction between the two sides will pull them together and close the clasp. 
     Portions of cord  56  and/or main housing unit  54  may contain some or all of the circuitry of device  10  of  FIG. 1 . The circuitry of device  10  of  FIG. 1  may be located entirely in cord  56 , may be located entirely in main unit  54 , or may be located partially in main unit  54  and partially in cord  56 . As shown in  FIG. 2 , for example, main unit may include electrical components  106  and cord  56  may include electrical components  104 . Components  106  and  104  may include any or all of the circuitry of device  10  of  FIG. 1 . 
     If desired, components  106  and/or components  108  may include sensors (e.g., sensors  20 ) that detect when clasp  102  and/or clasp  60  have been opened, that detect when device  10  is near other devices  10 , that detect when device  10  is coupled to other devices (e.g., interlocked as shown in  FIG. 7  or attached end-to-end as shown in  FIG. 8 ), that detect when device  10  has been stretched, that detect when device  10  is hung on or looped through an object, that detect when device  10  is beckoned, that detect when cord  56  is in a knot (e.g., using a capacitive sensing coaxial cable arrangement), and/or that detect other status information about device  10  and its surroundings. Control circuitry  12  may take suitable action based on the gathered status information. For example, magnetic sensors in unit  54  and/or cord  56  may detect when the magnetic portions of clasp  102  and/or clasp  60  have been moved away from each other and control circuitry  12  may take appropriate action. As examples, control circuitry  12  may adjust a sleep/wake status of device  10 , may issue a notification for a user of device  10 , may send a signal to device  40  so that control circuitry  42  in device  40  may take appropriate action (e.g., by notifying a user of device  40  of the open/closed status of device  10  with visual output, haptic output, audio output, or other output), may adjust charging operations, and/or may take other actions. 
     As shown in  FIG. 2 , cord  56  may include conductive paths such as paths  108 . Paths  108  may include one or more conductive lines for carrying power signals, data signals, control signals, and/or other signals. Paths  108  may be formed from conductive strands of material in fabric, metal traces on printed circuits, flexible substrates, or other substrates, conductive polymer (e.g., an elastomeric polymer with conductive filler such as carbon-loaded elastomeric polymer), metal traces deposited by physical vapor deposition and/or electrochemical deposition, metal foil, conductive polymer that is deposited on fabric, and/or other conductive patch structures. Paths  108  may be used for coupling components  104  to other components  104 , for coupling components  104  to components  106  in main unit  54 , and/or for other functions. If desired, conductive paths  108  may be used in forming an antenna such as antenna  28  of  FIG. 1 . Antenna(s)  28  may be coupled to wireless communications circuitry  26 . 
     In arrangements where device  10  receives wireless power using inductive charging components, cord  56  may incorporate a coil such as coil  34 . Coil  34  may be formed from one or more conductive lines that run around item  10  (e.g., ring-shaped cord  56  of item  10  may include conductive strands of material such as insulated and/or bare wire that form a wireless power receiving coil with one turn, at least two turns, at least three turns, at least 10 turns, fewer than 15 turns, fewer than 8 turns, or other suitable number of turns). 
     Devices such as device  10  of  FIG. 2  may use input-output devices  14  in components  106  and  104  to gather any suitable input and provide any suitable output. As an example, device  10  may use motion sensor(s) such as accelerometers to gather motion data and analyze a user&#39;s activity (e.g., running, walking, cycling, stair climbing, hiking etc.), may use blood pressure sensors to gather blood pressure information, may use heart rate sensors to gather heart rate information, may include blood sugar sensors for gathering blood sugar levels, may use blood oxygen sensors to measure a user&#39;s blood oxygen level, may use location tracking circuitry to track a user&#39;s location (e.g., location relative to another electronic device such as electronic device  40  or geographic location such as geographic coordinates), etc. If desired, accelerometers and/or other sensors may gather information on a user&#39;s respiration rate (e.g., by extracting respiration rate information from accelerometer readings). Health data, intentional user input (e.g., button press input on force sensors, touch sensors, and/or other input devices, voice commands gathered with a microphone, gesture input, tap input, etc.), environmental readings, and/or other information on the user and the user&#39;s surroundings may be gathered by devices  14  and processed by control circuitry  12 . Control circuitry  12  may also use the output devices of input-output devices  14  to provide haptic output, audio output, visual output (e.g., status light indicator output, display output such as displayed images of text, graphics, and/or video, etc.), and/or other output may be provided. 
     In some configurations, device  10  may be used in isolation (e.g., as a wrist band with input and output capabilities). In other configurations, device  10  may operate in conjunction with external equipment (e.g., device  40  of  FIG. 1 ). As an example, device  10  may gather health data, location data, and/or other information using input-output devices  14  and may provide this information to device  40  wirelessly. Device  40  can process this data and can take suitable action (e.g., by using its input-output devices to provide output to a user or by directing device  10  to provide output to the user using the input-output circuitry  14  of device  10 ). 
     Components  106  and  104  may be located internally within device  10 , may be located on the outer surfaces of device  10 , and/or may be located within device  10  adjacent to the outer surfaces of device  10 . For example, components  104  of cord  56  may be located within an outer fabric tube and/or may be located on the inner and/or outer surfaces of cord  56 . Components  106  of main unit  54  may be located within an outer housing member and/or may be located on the inner and/or outer surfaces of unit  54 . If desired, cord  56  and/or main unit  54  may include one or more openings through which electrical components transmit and/or receive signals. 
     As an example, components  106  may include light sources  16  (e.g., a pixel array, one or more light-emitting diodes, etc.) to form a light output region such as light output region  58  on main unit  54  of  FIG. 2 . Region  58  may be circular, oval, rectangular, and/or may have other shapes. Region  58  may be a single continuous area on unit  54  and/or may include multiple discrete areas. Region  58  of  FIG. 2  extends continuously around the diameter of main unit  54 , but regions such as region  58  may, if desired, extend only partway around the diameter of main unit  54 , may extend radially or axially along unit  54 , may be curved, may be flat, or may have other configurations. Region  58  may include input devices (e.g., components  18  and  20  of  FIG. 1  such as touch sensors, buttons, force sensors, cameras, etc.) and may include output devices (e.g., haptic device  22  and light sources  16  of  FIG. 1 ). 
     Light output region  58  may include status indicator lights (e.g., a light-emitting diode that serves as a power indicator, and other light-based output devices) and/or may include arrays (e.g., one-dimensional arrays or two-dimensional arrays) of pixels for forming displays such as liquid crystal displays, organic light-emitting diode displays, electrophoretic displays, displays formed from Janus particles, displays formed from crystalline semiconductor dies (microLEDs), etc. Light sources  16  in light output region  58  may be arranged in a circular pattern, a rectangular pattern (e.g., a rectangular array having rows and columns), may be arranged in a pattern with a coarse pitch (e.g., a pixel-to-pixel spacing of 0.1-1 mm, greater than 0.5 mm, less than 2 mm, etc.) to serve as a status indicator or a display with a relatively low resolution and/or may be arranged in a pattern with a fine pitch (e.g., a pixel-to-pixel spacing of 0.01 mm, less than 0.01 mm, 0.01-0.1 mm, more than 0.05 mm, etc.) to serve as a display that displays images. Light sources  16  in light output region  58  may include light-emitting diodes such as bare unpackaged crystalline semiconductor dies and/or packaged light-emitting diodes. Light sources  16  in light output region  58  may operate at infrared, ultraviolet, and/or visible light wavelengths. For example, light sources  16  may supply visible light such as red, green, blue light, white light, etc. Arrangements in which light sources  16  form a black and white display or status indicator may also be used. Light sources  16  may include a backlight (e.g., in a liquid crystal arrangement), may be self-emitting (e.g., in a light-emitting diode or organic light emitting diode arrangement), and/or may be passive (e.g., in a electrophoretic or Janus particle arrangement). 
     During operation, light sources  16  of light output region  58  may be used to provide a user of device  10  with visual output such as alerts (e.g., timer alerts, incoming message alerts, etc.), emojis, messages, text, graphics, images, moving images, flashing lights or lights of particular colors or patterns of colors that serve as status indicators (e.g., power level indicators, wireless signal strength indicators, hear beats per minute readouts, an ultraviolet light exposure indicator, etc.), and/or other suitable visual output. If desired, images, messages, or status information on light output region  58  may be displayed at a predetermined time, may be displayed in response to device  10  being opened or closed, and/or may be displayed in response to other input (e.g., input from sensors  20 , input from a user through device  18 , etc.). Status indicator light output on region  58  may be a solid illuminated region, may be faded in and out, may be pulsed, etc. If desired, images may move around the diameter of housing unit  54  or may remain in one place on housing unit  54 . 
       FIG. 3  shows device  10  in an “open” state in which one end of cord  56  is detached from main unit  54 . If desired, both ends of cord  56  may be detached from unit  54 . The diameter D of cord  56  may be between 2 mm and 10 mm, between 3 mm and 5 mm, between 3.5 mm and 4.5 mm, between 3 mm and 6 mm, greater than 10 mm, less than 10 mm, or any other suitable diameter or width. The length L of cord  56  may be between 150 mm and 210 mm, between 100 mm and 200 mm, between 50 mm and 300 mm, between 200 mm and 400 mm, greater than 200 mm, less than 200 mm, or any other suitable length. 
     A user of device  10  may place device  10  in a closed state (e.g., as shown in  FIG. 2 ) or an open state (e.g., as shown in  FIG. 3 ), by manipulating a clasp such as clasp  106  and/or  60  or by providing other suitable input (e.g., touch input, force input, button input, motion input, etc.). If desired, device  10  may be locked in a closed state such as the closed loop state of  FIG. 2 . The locking of device  10  may be an electronic or digital locking mechanism (e.g., in which control circuitry  12  renders the unlocking mechanism or other input device inactive until appropriate actions have taken place such as user authentication) or may be a mechanical or electromechanical locking mechanism. User authentication may be achieved through a touch sensor (e.g., by entering a passcode or other appropriate touch input), a motion sensor or camera that detects an appropriate gesture such as a hand wave sequence, a biometric sensor (e.g., that detects a user&#39;s fingerprint), a face identification sensor (e.g., an infrared camera that captures image of a user&#39;s face), or other suitable user authentication circuitry. Once a user&#39;s identity has been authenticated, control circuitry  12  may unlock device  10  and/or may take other suitable actions. If desired, different privileges may be assigned to different users such that control circuitry  12  may enable or disable certain functions depending on which user is using device  10 . 
     If desired, control circuitry  12  may use haptic output devices  22  to change the shape of cord  56 . This may include, for example, changing the shape of cord  56  from a furled shape as shown in  FIG. 2  to an unfurled shape as shown in  FIG. 3 , or vice versa. In one illustrative arrangement, fabric  36  of cord  56  may be formed using piezoelectric fibers that are configured to change the shape of cord  56  from a furled shape as shown in  FIG. 2  to an unfurled shape as shown in  FIG. 3 , or vice versa. In another illustrative arrangement, control circuitry  12  may change the shape of cord  56  using magnetic structures such as magnetic linkages that furl and unfurl under an appropriate electromagnetic field. 
     A cross-sectional side view of an illustrative layer of fabric for device  10  is shown in  FIG. 4 . As shown in  FIG. 4 , fabric  36  may be formed from intertwined strands of material such as strands  110  and strands  112 . With one suitable arrangement, fabric  36  may be a woven fabric (e.g., strands  110  may be weft strands and strands  112  may be warp strands). Other arrangements may be used for intertwining strands of material for forming fabric  36  for device  10 , if desired. In general, fabric  36  may be woven, knitted, braided, may be intertwined to form felt, or may contain strands of material that have been intertwined using other intertwining techniques. Fabric  36  may include one or more woven layers and/or one or more fabric layers formed from other intertwining techniques. If desired, layers of plastic and/or other materials may be coupled to one or more layers of fabric. In some arrangements, fabric  36  may include coatings (e.g., polymer coatings to prevent accumulation of dirt, materials that serve as moisture barrier layers, wear resistant coatings, transparent coatings such as patterned translucent coatings, etc.). These coating materials may penetrate into fabric  36  and/or may form layers on the inner and/or outer surfaces of fabric  36 . 
     The strands of material that form fabric  36  may include insulating strands (e.g., polymer yarn, etc.) and conductive strands (e.g., bare wire and/or wire coated with insulation). The strands of material may be monofilaments, may be multifilament strands (sometimes referred to herein as yarns, threads, or multifilament wire), may be formed from metal (e.g., metal monofilaments and/or yarns formed from multiple monofilament wires), may be formed from dielectric (e.g., polymer monofilaments and yarns formed from multiple polymer monofilaments), may include dielectric cores covered with conductive coatings such as metal (e.g., metal coated dielectric monofilaments and yarns of metal coated polymer-core monofilaments may be used to form conductive monofilaments and conductive yarns, respectively), may include outer insulating coatings (e.g., coatings of polymers or other dielectrics may surround each metal-clad polymer monofilament or each collection of metal-clad polymer monofilaments in a yarn, polymer insulation may enclose a multifilament metal wire, etc.), or may be other suitable strands of material for forming fabric. Fabric  36  may be formed using monofilaments, multifilament strands of material (yarns), combinations of these arrangements (e.g., fabric with polymer coated wires interspersed with insulating yarn), etc. The diameter of strands  110  and  112  that are formed from yarns containing multiple monofilaments may be, for example, 0.25 mm, may be 0.1 to 0.5 mm, may be more than 0.2 mm, may be less than 2 mm, or may be any other suitable diameter (width). 
     In some arrangements, fabric  36  may include stretchable (elastic) strands of material. Strands  110  and/or  112  may, for example, be formed from an elastomeric polymer that can stretch and return elastically to its unstretched state (e.g., when strands  110  and  112  are not stretched more than their elongation-to-break limits). As an example, strands  110  and  112  may be formed from synthetic rubber or spandex (a copolymer of polyoxyethylene and polyurethane, sometimes referred to as Lycra® or elastane). Fabric  36  may instead or additionally have strands that are less stretchable, but that add strength to fabric  36 . For example, strands  110  and/or strands  112  may be nylon strands or strands of other strong material. These examples are merely illustrative. 
     If desired, circuitry or other components of device  10  may be incorporated into strands  110  and/or strands  112 . For example, strands  110  and/or strands  112  may be formed from fiber optic cables for transmitting optical signals, may contain Janus particles for forming a visual output region, may contain magnetic particles for forming a magnetic clasp or other structure, may contain haptic output devices  22  such as piezoelectric fibers or other piezoelectric materials, may form part of an antenna, may form part of an inductive charging coil, and/or may serve other functions. 
     Device  10  may be coupled to any suitable person, object, or animal.  FIG. 5  shows how Device  10  may be threaded through or otherwise attached to an object such as object  62 . Object  62  may be a key, a wallet, a suitcase, part of a child clothing, a dog or cat collar, a bicycle, a handbag, a shopping bag, an electronic device such as a pair of headphones, or any other suitable object. If desired, device  10  may be used as a tracking device to track the location of object  62 . For example, device  10  may wirelessly communicate with device  40  of  FIG. 1  to provide device  40  with information about the location of object  62 . A user of device  40  may in turn use device  40  to communicate with device  10 . For example, device  40  may instruct device  10  to provide output (e.g., audio output, visual output, haptic output, etc.) to help the user locate object  62 . Location information may be gathered and transmitted to device  40  in real time or may be gathered and stored for later review by a user of device  10  and/or device  40 . 
       FIG. 6  shows how device  10  may be hung on an object such as object  64 . Object  64  may be a door knob, a chair, a lamp, an electronic device such as a television, or any other suitable object. If desired, device  10  may be used as a spatial or status awareness device for obtaining information about its surroundings and/or about object  64  to which it is attached. For example, device  10  may use sensors (e.g., sensors  20 ) to detect what object  64  is, to detect what the status is of object  64  (e.g., open or closed status, locked or unlocked status, charging status, brightness status, etc.), to detect a characteristic of the environment around object  64  (e.g., temperature, brightness, humidity, number of people nearby, etc.), and/or to gather other information about object  64  and/or the environment around object  64 . 
       FIG. 7  shows how multiple devices  10  may be interlocked with one another. In the example of  FIG. 7 , two devices  10  have been threaded through a third device  10 . Other arrangements with multiple interlocking devices  10  may be used, if desired. 
       FIG. 8  shows how multiple devices  10  may be daisy-chained together to form a single loop with multiple cords  56  and multiple housing units  54 . If desired, two, three, four, or more than four devices  10  may be strung together end-to-end to form a larger loop of any suitable size. 
     Interlocking devices  10  ( FIG. 7 ) and connecting devices  10  end-to-end ( FIG. 8 ) may enable certain types of communication between devices  10 . For example, coupling devices  10  in this way may enable one device  10  to share charge with another device  10 , may enable data to be transferred form one device  10  to another device  10 , and/or may provide other communication capabilities between devices  10 . Signals between devices  10  may be conveyed wirelessly or through electrical connections. 
       FIG. 9  shows how device  10  may be worn on a user&#39;s neck  66 . If desired, multiple devices  10  may be daisy-chained together (e.g., as shown in the example of  FIG. 8 ) to increase the length of the loop so that it fits around objects larger than a user&#39;s wrist. 
       FIG. 10  shows how a user may wear multiple devices  10 . If desired, each device  10  may have different functionality than the other devices  10  (e.g., one device  10  may be geared towards fitness applications and another device  10  may be geared towards gaming applications), or devices  10  may have the same functionality. 
       FIGS. 11, 12, 13, 14, 15, and 16  show illustrative form factors that device  10  may have. 
     In the example of  FIG. 11 , device  10  is formed from a single cord  56  without a main housing unit  54 . With this type of configuration, the circuitry of device  10  may be contained entirely within cord  56  (e.g., in components  104  of cord  56 ). 
     In the example of  FIG. 12 , device  10  includes main housing unit  54  and cord  56 . Main housing unit  54  and cord  56  may form a continuous loop. 
     In the example of  FIG. 13 , device  10  includes main housing unit  54  coupled to one end (end  114 ) of cord  56 . The opposing end of cord  56  (end  116 ) is not attached to housing unit  54 . If desired, a clasp mechanism may be used to attach end  116  to housing  54  or end  116  may remain detached from housing  54 . 
     In the example of  FIG. 14 , both opposing ends  114  and  116  of cord  56  are attached to a respective housing unit  54 . Both housing units  54  may contain circuitry or circuitry may be contained only in one of housing units  54 . 
     In the example of  FIG. 15 , device  10  has two opposing ends that can be interlocked or otherwise attached. For example, housing unit  54  on end  114  of cord  56  may have one or more engagement features such as engagement feature  70  and end  116  of cord  56  may have a corresponding engagement feature  72 . Engagement feature  70  may be a hole, recess, or other feature configured to receive corresponding engagement feature  72  (e.g., a protrusion, spring-loaded pin, or other engagement feature). As shown in  FIG. 16 , engagement feature  70  of housing  54  may receive engagement feature  72  of cord  56 . This is, however, merely illustrative. If desired, cord  56  may have a recess or hole and housing unit  54  may have a protruding structure that protrudes into the recess or hole. 
       FIG. 17  shows how separate add-on structures  80  may be strung onto cord  56  of device  10 . Add-on structures  80  may be free of electronics (e.g., may serve a decorative, cosmetic, or tactile purpose) or add-on structures  80  may contain electronics. For example, add-on structures  80  may include displays, sensors, location tracking circuitry such as global positioning system receiver circuitry, medical monitoring circuitry, or other suitable circuitry. If desired, each individual add-on structure  80  may have a different functionality, and the user may select which functionality to add to device  10  by selecting the appropriate add-on structure  80 . In the example of  FIG. 17 , add-on structures  80  have a ring-shape with a central opening that allows structures  80  to be strung onto device  10  by inserting cord  56  through the opening of structures  80 . This is, however, merely illustrative. If desired, structures  80  may have other suitable shapes. Device  10  may wirelessly communicate with add-on structures  80  and/or add-on structures  80  may wirelessly communicate with device  40 . 
     The example of  FIG. 17  in which add-on structures are strung onto cord  56  such that cord  56  and add-on structures  80  are concentric is merely illustrative. In the example of  FIG. 18 , add-on structures  80  are added in-line with housing unit  54 . The attachment mechanism between add-on structures  80  and housing unit  54  may be based on magnetic structures, mechanical structures, electrical structures, or other suitable attachment structures. 
       FIGS. 19, 20, 21, and 22  show illustrative arrangements for visual output on main housing unit  54  of device  10 . In the example of  FIG. 19 , main housing unit  54  includes a status indicator  82 . Status indicator  82  may be formed from one or more light-emitting diodes, one or more liquid crystal structures, one or more electrophoretic structures, Janus particles, or other visual output structures. 
     In the example of  FIG. 20 , main housing unit  54  is free of visual output structures such as displays and status indicators. If desired, main housing unit  54  may provide non-visual output such as haptic output, audio output, or other suitable output. 
     In the example of  FIG. 21 , main housing unit  54  has visual output region  58  extending across only a portion of main housing unit  54 . Visual output region  58  may contain an array of pixels (e.g., light-emitting diode pixels, organic light-emitting diode pixels, electrophoretic pixels, pixels based on Janus particles, etc.). 
     In the example of  FIG. 22 , visual output region  58  covers most or all of the outer surface of main housing unit  54 . This gives the appearance of a boundary-less display on main housing unit  54  of device  10 . 
       FIGS. 23, 24, 25, and 26  show an illustrative case for devices  10 . As shown in  FIG. 23 , case  86  may include upper housing member  88 , lower housing member  90 , and column  92  extending from lower housing member  90 . Column  92  may be configured to receive devices  10 . For example, devices  10  may be placed onto column  92  such that column  92  passes through the loops formed by devices  10  (e.g., such that devices  10  wrap around column  92 ). Case  86  may be formed from metal, polymer, ceramic, glass, silicone, other materials, or a combination of these materials. 
     If desired, case  86  may be free of electronics or case  86  may contain circuitry such as circuitry  94 . Circuitry  94  may include some or all of the circuitry of device  40  of  FIG. 1 . For example, circuitry  94  may include a battery and/or wireless power transmitting circuitry that supplies wireless power signals that are received by wireless power receiving circuitry  32  in device  10 . Wireless power transmitting circuitry  94  may transmit power wirelessly using inductive wireless power transfer, using capacitive wireless power transfer, and/or other wireless power transfer configurations (e.g., optical). With one illustrative configuration, wireless power receiving circuitry  32  in device  10  includes a wireless power receiving circuit having a coil (e.g., coil  34 ) and associated circuitry (e.g., one or more capacitors) and includes a rectifier that converts received alternating-current power signals from the wireless power receiving circuit to direct-current power for powering device  10 . In this type of configuration, wireless power transmitting circuitry  94  may include inverter circuitry that is used to supply alternating-current (AC) signals (e.g., alternating-current signals controlled via pulse-width modulation) to a wireless power transmitting circuit that includes one or more coils and one or more associated capacitors. During operation, the signals supplied by the inverter circuitry cause the coil(s) in the wireless power transmitting circuit to emit wireless power signals, which are received and converted to direct-current (DC) power by circuitry  32 . This is, however, merely illustrative. If desired, case  86  may charge devices  10  using an electrical connection. 
     Case  86  may include one or more visual output regions such as visual output region  140 . Visual output region  140  may include status indicator lights (e.g., a light-emitting diode that serves as a power indicator, and other light-based output devices) and/or may include arrays (e.g., one-dimensional arrays or two-dimensional arrays) of pixels for forming displays such as liquid crystal displays, organic light-emitting diode displays, electrophoretic displays, displays formed from Janus particles, displays formed from crystalline semiconductor dies (microLEDs), etc. Light sources in light output region  140  may be arranged in a circular pattern, a rectangular pattern (e.g., a rectangular array having rows and columns), may be arranged in a pattern with a coarse pitch (e.g., a pixel-to-pixel spacing of 0.1-1 mm, greater than 0.5 mm, less than 2 mm, etc.) to serve as a status indicator or a display with a relatively low resolution and/or may be arranged in a pattern with a fine pitch (e.g., a pixel-to-pixel spacing of 0.01 mm, less than 0.01 mm, 0.01-0.1 mm, more than 0.05 mm, etc.) to serve as a display that displays images. Light sources in light output region  140  may include light-emitting diodes such as bare unpackaged crystalline semiconductor dies and/or packaged light-emitting diodes. Light sources in light output region  140  may operate at infrared, ultraviolet, and/or visible light wavelengths. For example, light output region  140  may supply visible light such as red, green, blue light, white light, etc. Arrangements in which light output region  140  is a black and white display or status indicator may also be used. Light output region  140  may include a backlight (e.g., in a liquid crystal arrangement), may be self-emitting (e.g., in a light-emitting diode or organic light emitting diode arrangement), and/or may be passive (e.g., in a electrophoretic or Janus particle arrangement). 
     If desired, circuitry  94  may include other circuitry such as communications circuitry and one or more speakers and microphones to serve as a virtual assistant for a user of device  10  and case  86 . Circuitry  94  may be located in base portion  90 , column  92 , and/or in upper portion  88  of case  86 . 
     Upper portion  88  and lower portion  90  may close using any suitable closure mechanism (e.g., a snap fit, a twist closure, a screw closure, a flexible closure, etc.). 
       FIG. 24  shows how multiple devices  10  may be stored in case  86 , if desired. Case  86  may be configured to charge all devices  10  (e.g., in sequence, at the same time, etc.) when placed on column  92 . 
       FIG. 25  shows an example in which case  86  has one or more transparent portions. For example, upper portion  88  of case  86  may be transparent. This allows a viewer such as viewer  96  viewing case  86  in direction  98  to see through case  86  and easily discern whether device(s)  10  are present in case  86  without having to open case  86 . 
       FIG. 26  shows an example in which case  86  is opaque. Case  86  may, if desired, be configured to change opacity according to a given status. For example, case  86  may be transparent when empty and opaque when device(s)  10  are inside, or vice versa. As another example, case  86  may change opacity according to the level of charge contained in devices  10  (e.g., transparent when devices  10  have no charge and opaque when devices  10  are fully charged, or vice versa). The opacity of case  86  may be adjusted using light modulating structures such as liquid crystals, switchable filters, or other light modulating structures. 
     If desired, device  10  and case  86  may be charged wirelessly on a wireless charging mat such as charging mat  100  of  FIG. 27 . Charging mat  100  may include wireless power transmitting circuitry  120  that supplies wireless power signals that are received by wireless power receiving circuitry  32  in device  10 . If desired, case  86  may also include wireless power receiving circuitry that receives wireless power signals from charging mat  100 . Wireless power transmitting circuitry  120  in mat  100  may transmit power wirelessly using inductive wireless power transfer, using capacitive wireless power transfer, and/or other wireless power transfer configurations (e.g., optical). With one illustrative configuration, wireless power receiving circuitry  32  in device  10  includes a wireless power receiving circuit having a coil (e.g., coil  34 ) and associated circuitry (e.g., one or more capacitors) and includes a rectifier that converts received alternating-current power signals from the wireless power receiving circuit to direct-current power for powering device  10 . Wireless power receiving circuitry in case  86  may also include a wireless power receiving circuit having a coil and associated circuitry (e.g., one or more capacitors). In this type of configuration, wireless power transmitting circuitry  120  may include inverter circuitry that is used to supply alternating-current (AC) signals (e.g., alternating-current signals controlled via pulse-width modulation) to a wireless power transmitting circuit that includes one or more coils and one or more associated capacitors. During operation, the signals supplied by the inverter circuitry cause the coil(s) in the wireless power transmitting circuit to emit wireless power signals, which are received and converted to direct-current (DC) power by circuitry  32  in device  10  and by wireless power receiving circuitry in case  86 . 
       FIGS. 28, 29, and 30  illustrate how the location of device  10  may be tracked and conveyed to a user. In  FIG. 28 , device  10  moves along path  126  from point  122  to point  124 . Along path  126 , sensors in device  10  track the movement and location of device  10  (and thus the movement and location of the person, animal, or object to which device  10  is attached). This motion and location information may be stored in device  10  and/or may be conveyed to an external electronic device such as device  40  of  FIG. 1 . Motion and location information may, if desired, be processed to determine the type of activity being performed along motion path  126  (e.g., running, walking, cycling, stair climbing, etc.). 
       FIGS. 29 and 30  show how the location of device  10  relative to an external electronic device may be conveyed to a user through the external electronic device. In the example of  FIG. 29 , a user is wearing electronic device  40  between first and second electronic devices  10  such as device  10 A and  10 B. Electronic device  40  may be a wrist-watch or other electronic device having a display such as display  74 . Display  74  may display images  76 A and  76 B corresponding to associated devices  10 A and  10 B, respectively. The locations of images  76 A and  76 B on display  74  may be based on the locations of devices  10 A and  10 B relative to device  40 . For example, image  76 A may be displayed on a left side of display  74  indicating device  10 A is to the left of device  40 , and image  76 B may be displayed on a right side of display  74  indicating device  10 B is to the right of device  40 . 
       FIG. 30  shows that display  74  of device  40  may not only display the location of devices  10 A and  10 B relative to device  40 , but may also display the orientations of devices  10 A and  10 B relative to device  40 . 
     As shown in  FIG. 31 , external equipment such as electronic device  40  in system  8  may contain sensors such as one or more cameras  130  (e.g., visual light cameras, infrared cameras, etc.). Electronic device  40  may, as an example, form part of an augmented reality (mixed reality) or virtual reality system (e.g., a system that includes a head-mounted device, glasses, a helmet, or other head-mountable support structures). Visual markers  128  may be placed on device  10  and, if desired, on other locations in the user&#39;s environment. Markers  128  may be, for example, passive visual markers such as bar codes, cross symbols, or other visually identifiable patterns and may be applied to device  10  and/or other objects such as a tabletop or other work surface. 
     Markers  128  may, if desired, include light-emitting components (e.g., visual light-emitting diodes and/or infrared light-emitting diodes modulated using identifiable modulation codes) that are detected using cameras. Markers  128  may help inform system  8  of the location of the user&#39;s virtual work surface and one or more of the user&#39;s fingers as a user is interacting with a computer or other equipment in system  8 . 
     Visual markers  128  on device  10  and/or inertial measurement units in device  10  (e.g., accelerometers, compasses, and/or gyroscopes) may be used in tracking the hand locations (e.g., the locations of devices  10 ) relative to other markers in the user&#39;s work area. At the same time, system  8  may display associated visual content for the user. The user may interact with the displayed visual content by supplying force input, motion input (e.g., air gestures), taps, shearing force input, and other input gathered from device  10  by inertial measurement units in device  10  and/or force sensors and other sensors in device  10 . 
     For example, information on the location of device  10  relative to other marks in system  8  may be gathered by control circuitry  42  in device  40  or other electronic equipment in system  8  (e.g., a computer, cellular telephone, or other electronic device coupled to device  40 ) during operation of system  8  while monitoring device  10  for force input, gesture input (e.g., taps, three-dimensional air gestures, etc.) that indicate that a user has selected (e.g., highlighted), moved, or otherwise manipulated a displayed visual element and/or provided commands to system  8 . As an example, a user may make an air gesture such as a left hand wave to move visual content to the left. System  8  may use markers  128  and/or inertial measurement units in device  10  to detect the left hand wave gesture and can move visual elements being presented to the user with a display in device  40  in response to the left hand wave gesture. As another example, a user may select a visual element in the user&#39;s field of view by tapping on that element. 
     In this way, control circuitry in device  40 , and/or other control circuitry in system  8  may allow a user to manipulate visual elements being viewed by the user (e.g., virtual reality content or other visual content being presented with a head-mounted device such as augmented reality googles or other device  40  with a display). 
     Markers  128  on device  10  may be formed from ink on cord  56  and/or housing unit  54 , coatings on cord  56  and/or housing unit  54 , surface features on cord  56  and/or housing unit  54 , or other suitable structures in device  10 . In arrangements where markers  128  are tracked with an infrared camera, marks  128  may be formed from infrared-reflective ink or coatings. 
     The foregoing is merely illustrative and various modifications can be made to the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20190829
Publication Date: 20211116
Grant Date: 20211116
Priority Date: 20180907
Inventors: PUSKARICH, PAUL G.
Assignee: APPLE INC
CPC Classifications: [{"code": "H02J50/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J50/005", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/0044", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J7/0044", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J50/10", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02J7/025", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02J7/027", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 78524285