PATENT DOCUMENT

Publication Number: US-10561367-B1
Application Number: US-201815985538-A
Country: US
Kind Code: B1

Title: Electronic devices having adjustable fabric

Abstract:
Strands of material may be intertwined to form fabric for a strap or other structure in an electronic device. Conductive strands in the fabric may have middle-of-strand knots. When current is applied to a conductive strand, the knot in that strand may produce magnetic fields that cause the knot to adjust tension in the fabric. Conductive strands may intersect at nodes. Each node may have a knot formed from one or more conductive strands at the node. An electronic device or other item may have a magnetic field source that applies a fixed or time-varying magnetic field to the fabric. Each node in the fabric may include magnetic material. The magnetic material may be magnetized by applying current through the conductive strands. After magnetization, each node may interact with the magnetic field from the source of magnetic field to thereby adjust fabric tension, shape, movement, etc.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 input-output devices; 
 control circuitry configured to gather input with the input-output devices and configured to supply output with the input-output devices; and 
 fabric formed from strands of material, wherein the strands of material include a conductive strand of material having a mid-strand knot, wherein the control circuitry is configured to apply a signal to the conductive strand that flows through the mid-strand knot and adjusts tension in the fabric. 
 
     
     
       2. The electronic device defined in  claim 1  wherein the fabric is configured to form a strap, wherein the control circuitry is configured to apply a signal to the conductive strand to tighten the strap, wherein the input-output devices include a sensor, and wherein the control circuitry is configured to gather a sensor measurement while the strap is tightened about a body part of a user. 
     
     
       3. The electronic device defined in  claim 2  further comprising a housing, wherein the input-output devices include a display in the housing and wherein the strap is coupled to the housing. 
     
     
       4. The electronic device defined in  claim 1  wherein the input-output devices comprise a sensor in the fabric. 
     
     
       5. The electronic device defined in  claim 4  wherein the control circuitry is configured to receive feedback from the sensor while applying the signal to the knot to adjust the tension in the fabric. 
     
     
       6. The electronic device defined in  claim 1  further comprising an additional conductive strand, wherein the mid-strand knot includes portions of the conductive strand and the additional conductive strand. 
     
     
       7. The electronic device defined in  claim 1  further comprising a magnetic field source configured to apply a magnetic field to the fabric, wherein the mid-strand knot is configured to produce a magnetic field that interacts with the magnetic field applied by the magnetic field source. 
     
     
       8. The electronic device defined in  claim 1  wherein the mid-strand knot is formed at a node in the fabric that includes a member formed from magnetic material. 
     
     
       9. The electronic device defined in  claim 1  wherein the input-output devices comprise a sensor in the fabric, wherein the control circuitry is configured to gather feedback on the tension in the fabric from the sensor while applying the signal to the conductive strand, and wherein the sensor comprises an optical fiber sensor having an optical fiber in the fabric that is configured to measure bending in the fabric due to the tension. 
     
     
       10. The electronic device defined in  claim 1  wherein the input-output devices comprise a sensor in the fabric, wherein the control circuitry is configured to gather feedback on the tension in the fabric from the sensor while applying the signal to the conductive strand, and wherein the sensor comprises a force sensor configured to measure the tension. 
     
     
       11. The electronic device defined in  claim 10  wherein the input-output devices comprise a strain gauge, wherein the fabric forms a strap, and wherein the control circuitry is configured to use the strain gauge to measure tightening of the strap. 
     
     
       12. The electronic device defined in  claim 1  wherein the input-output devices comprise a sensor in the fabric, wherein the control circuitry is configured to gather feedback on the tension in the fabric from the sensor while applying the signal to the conductive strand, and wherein the sensor comprises a force sensing resistor. 
     
     
       13. A system, comprising:
 fabric having conductive strands of material, wherein the fabric has nodes that contain middle-of-strand knots; and 
 control circuitry configured to selectively adjust portions of the fabric by applying current to the middle-of-strand knots through the conductive strands of material. 
 
     
     
       14. The system defined in  claim 13  wherein the conductive strands of material include first conductive strands and second conductive strands that intersect at the nodes and wherein the middle-of-strand knots are located at the nodes. 
     
     
       15. The system defined in  claim 14  wherein the control circuitry is configured to supply first signals to the first conductive strands to produce first magnetic fields in the middle-of-strand knots and wherein the control circuitry is configured to supply second signals to the second conductive strands to produce second magnetic fields in the middle-of-strand knots. 
     
     
       16. The system defined in  claim 15  wherein the control circuitry is configured to selectively buckle the portions of the fabric by supplying the first and second signals to cause the first and second magnetic fields to interact. 
     
     
       17. The system defined in  claim 13  wherein each node includes magnetic material. 
     
     
       18. The system defined in  claim 17  wherein the control circuitry is configured to magnetize the magnetic material by applying the current. 
     
     
       19. The system defined in  claim 17  further comprising a magnetic field source configured to produce a static magnetic field to the fabric, wherein the control circuitry is configured to selectively buckle portions of the fabric by applying current to the middle-of-strand knots that causes the middle-of-strand knots to produce magnetic fields that interact with the static magnetic field. 
     
     
       20. Apparatus, comprising:
 fabric that includes conductive strands of material, wherein the fabric includes nodes that include middle-of-strand knots each of which is formed from the conductive strands of material; and 
 control circuitry configured to adjust tension in the fabric by applying signals to the conductive strands that produce interacting magnetic fields in the nodes. 
 
     
     
       21. The apparatus defined in  claim 20  wherein the fabric is configured to be worn on a body part. 
     
     
       22. The apparatus defined in  claim 21  wherein the fabric is configured to form a strap that extends around the body part. 
     
     
       23. The apparatus defined in  claim 22  further comprising a housing having a display, sensors, a battery, and wireless communications circuitry, wherein the housing is coupled to the wrist strap. 
     
     
       24. The apparatus defined in  claim 20  wherein each node is coupled to a respective gating circuit that is configured to receive input and to adjust current flow through the middle-of-strand knot based on the input.

Description:
FIELD 
     This relates generally to electronic devices and, more particularly, to electronic devices that include fabric. 
     BACKGROUND 
     It may be desirable to form electronic device structures from fabric. For example, a wristwatch may have a fabric strap. If care is not taken, fabric structures may not perform as desired. For example, a fabric strap may be uncomfortably tight or may be too loose. In some situations, tension variations in fabric straps for wristwatches can hinder accurate wristwatch sensor measurements. 
     SUMMARY 
     Strands of material may be intertwined to form fabric. The fabric may be configured to form a strap or other structure for an electronic device. The electronic device may include input-output devices such as sensors, buttons, displays, and other components. 
     Conductive strands in the fabric may have knots such as middle-of-strand knots. When current is applied to a conductive strand, the knot in that strand may produce magnetic fields that cause the knot to adjust tension in the fabric. Fabric tension adjustments may cause motion in the fabric and changes in the shape of the fabric. 
     Conductive strands may intersect at nodes. Each node may have a knot formed from loops of one or more conductive strands. An electronic device or other item may have a magnetic field source that applies a fixed or time-varying magnetic field to the fabric. The magnetic fields produced by the knots may interact with the magnetic field produced by the magnetic field source. 
     Nodes in the fabric may include magnetic material. The magnetic material may be magnetized by applying current through the conductive strands. After magnetization, the magnetic material may interact with magnetic fields produced by other magnetized magnetic material at the nodes and/or magnetic field from the source of magnetic field. These interactions may serve to adjust fabric tension, shape, movement, etc. 
     Nodes may include gating circuits. The gating circuits may have gating devices such as transistors, photosensitive circuits, or other circuitry that allows the gating circuits to control current flow through knots at the nodes based on control input. During operation of an electronic device, control circuitry in the electronic device may apply currents to mid-strand knots and other structures formed in the fabric to adjust the shape, tension, and/or movement of the fabric. 
     To provide the control circuitry with feedback, sensing circuitry can be incorporated into the fabric. The sensing circuitry may be used to measure fabric bending and other activities and may therefore be used in providing feedback to the control circuitry. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of an illustrative electronic device in accordance with an embodiment. 
         FIG. 2  is a perspective view of an illustrative electronic device with adjustable fabric being used to form a strap in accordance with an embodiment. 
         FIG. 3  is a side view of an illustrative device formed from adjustable fabric in accordance with an embodiment. 
         FIG. 4  is a side view of illustrative fabric in accordance with an embodiment. 
         FIG. 5  is a top view of illustrative adjustable fabric in accordance with an embodiment. 
         FIG. 6  is a perspective view of a conductive strand having loops that create interacting magnetic fields in accordance with an embodiment. 
         FIG. 7  is a perspective view of an illustrative mid-strand knot in accordance with an embodiment. 
         FIGS. 8 and 9  are schematic diagrams of illustrative knots for use in adjustable fabric in accordance with an embodiment. 
         FIGS. 10 and 11  are top views of illustrative adjustable fabric in accordance with an embodiment. 
         FIG. 12  is a diagram of an illustrative adjustable fabric node based on a pair of magnetic structures looped with conductive strands in accordance with an embodiment. 
         FIGS. 13, 14, and 15  are diagrams of illustrative magnetic elements in different interaction configurations in accordance with an embodiment. 
         FIG. 16  is a diagram of an illustrative adjustable magnetic element that is interacting with a magnetic field from a magnet in accordance with an embodiment. 
         FIG. 17  is a diagram of an illustrative adjustable fabric node with a gating device in accordance with an embodiment. 
         FIG. 18  is a perspective view of illustrative three-dimensional fabric in accordance with an embodiment. 
         FIG. 19  is a diagram of an illustrative fiber-based sensor for detecting bending adjustable fabric in accordance with an embodiment. 
         FIG. 20  is a diagram of an illustrative force-sensing resistor in accordance with an embodiment. 
         FIG. 21  is a diagram of an illustrative strain gauge in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Items such as electronic device  10  of  FIG. 1  may be used to gather input from a user and the surrounding environment and may be used to supply a user with output. As an example, device  10  may be a wristwatch device that monitor&#39;s a user&#39;s pulse, a user&#39;s blood pressure, and other health characteristics, that makes other sensor measurements, and that provides the user with visual output, audible output, and/or haptic output. Device  10  may have a strap or other structures that allow device  10  to be worn on a user&#39;s body. For example, device  10  may have a band-shaped strap that allows device  10  to be worn on a user&#39;s wrist. The strap and/or other structures in device  10  can include fabric. In some arrangements, the fabric can be adjusted. For example, the fabric may include nodes that can be adjusted to selectively increase or decrease tension in various portions of a layer of fabric. This allows device  10  to buckle a fabric region to provide a user with haptic output and/or to adjust the size and/or shape of device  10 . For example, device  10  may have a wrist strap formed from adjustable fabric that can be tightened when it is desired to gather sensor measurements on a user&#39;s wrist and that can be loosened when it is desired to wear the wrist strap normally. 
     Electronic device  10  may be a stand-alone electronic device and/or may operate as an accessory that is used with ancillary electronic equipment. Device  10  may, as an example, be an electronic device such as a laptop computer, a computer monitor containing an embedded computer, a tablet computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wrist-watch device, a pendant device, a headphone or earpiece device, a device embedded in eyeglasses 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 navigation device, a remote control, an embedded system such as a system in which device  10  is mounted in a kiosk, in an automobile, airplane, or other vehicle, other electronic equipment that includes adjustable fabric, or equipment that implements the functionality of two or more of these devices. If desired, device  10 , which may sometimes be referred to as a fabric-based item or system, may be a removable external case for electronic equipment, may be a strap, may be a wrist band or head band, may be a removable cover for a device, may be a case or bag that has straps or that has other structures to receive and carry electronic equipment and other items, may be a necklace or arm band, may be a wallet, sleeve, pocket, or other structure into which electronic equipment or other items may be inserted, may be part of a chair, sofa, or other seating (e.g., cushions or other seating structures), may be part of an item of clothing or other wearable item (e.g., a hat, belt, wrist band, headband, sock, glove, shirt, pants, etc.), or may be any other suitable item. 
     Device  10  may have structures such as outer layers (e.g., the outermost layer in a housing), inner layers (e.g., layers that are overlapped by the outermost layer in device  10 ), and internal support structures that are formed from glass, metal, polymer, ceramic, wood, fabric, natural materials such as leather, and/or other materials. These layers of material may include rigid portions and flexible portions. In some configurations, the outermost layers of device  10  that form external surfaces for device  10  may be formed from flexible material. 
     Fabric in device  10  may be woven fabric, knit fabric, braided fabric, or fabric formed using strands of material formed using other strand intertwining techniques. By selecting materials such as fabric and/or other materials for the housing of device  10 , device  10  may configured to be soft (e.g., device  10  may have a fabric surface that yields to a light touch), may be configured to have a rigid feel (e.g., the surface of device  10  may be formed from a stiff fabric or hard polymer or other material), may be coarse, may be smooth, may have ribs or other patterned textures, and/or may have other configurations. 
     Device  10  may have control circuitry  24 . Control circuitry  24  may be formed from one or more integrated circuits such as microprocessors, microcontrollers, application-specific integrated circuits, digital signal processors, and/or other circuits and may be used to control the operation of electronic device  10  by controlling electrically controllable (electrically adjustable) components in device  10 . Control circuitry  24  may use communications circuitry  28  to support communications with one or more devices such as electronic device  30  (e.g., a wristwatch main unit, a cellular telephone or other portable device, wireless earbuds or other audio accessories, etc.). Device  30  may be attached to and/or incorporated into electronic device  10  (e.g., when device  10  is a strap for a wristwatch and device  30  is the main unit of the wristwatch) or electronic device  10  and electronic device  30  may be separate items that are configured to operate with each other (e.g., when one device is a case and the other is a device that fits within the case, etc.). Circuitry  28  may include antennas and other structures for supporting wireless communications with device  30  over communications link  32 . Link  32  may be a wired communications link or may be a wireless communications link. 
     Device  30  may be an electronic device such as a cellular telephone, computer, or other portable electronic device and device  10  may form a cover, case, bag, or other structure that receives the electronic device in a pocket, an interior cavity, or other portion of device  10 . In other situations, device  30  may be a wristwatch unit or other electronic device and device  10  may be a strap or other fabric-based item that is attached to device  30  (e.g., device  10  and device  30  may be used together to form a device such as a wristwatch with a strap). In still other situations, device  10  may be an electronic device (e.g., a wearable device such as a wrist device, arm band, hat, glove, clothing, etc.) and additional devices such as device  30  may include accessories or other devices that interact with device  10  such as wireless speakers, wireless ear buds, etc. Signal paths formed from conductive yarns and monofilaments (e.g., insulated and bare wires), metal traces on printed circuits, and/or other conductive paths may be used to route signals in device  10  and/or device(s)  30 . 
     Device  10  may include input-output devices  16 . Input-output devices  16  may be used to gather input from a user and to make measurements on the operating environment for device  10 . Input-output devices  16  may also be used in providing output. The output that is provided may be visual output, audio output, haptic output, wirelessly transmitted output, and/or other output. Output may include alerts (e.g., notifications of incoming messages, alarm timer alerts, calendar alerts, etc.), status information (e.g., battery status), time information, icons, text, graphics, video, audible alerts, haptic output (e.g., vibrating alerts, etc.), information on sensor measurements, and/or other output. 
     Input-output devices  16  may include buttons  18  (push buttons, rotary buttons, slider buttons, etc.). Input-output devices  16  may also include audio devices  36  (e.g., microphones and/or speakers). Sensors  26  in input-output devices  16  may include touch sensors (e.g., an optical touch sensor, an acoustic touch sensor, a capacitive touch sensor, or other suitable touch sensor) and/or force sensors (e.g., force sensors based on piezoelectric sensors, strain gauges, resistive force sensors, capacitive force sensors and/or other force sensors). Touch sensors and force sensors may, if desired, be implemented using conductive strands in fabric (e.g., conductive strands forming capacitive sensor electrodes in a capacitive touch and/or force sensor). Sensors  26  may also include gas pressure sensors, particulate sensors, ambient light sensors, optical proximity sensors, optical sensors such as cameras for gathering three-dimensional gesture input, infrared cameras and light sources (e.g., for iris scanning), temperature sensors, other optical sensors, gaze tracking sensors, sensors for measuring position and/or orientation such as accelerometers, gyroscopes, magnetic sensors (compasses) and/or inertial measurement units that contain multiple orientation sensors and/or position sensors, blood pressure sensors, heartbeat sensors, sensors for measuring electrocardiograms, electromyography sensors, blood oxygen sensors, other health monitoring sensors, and/or other sensors. 
     Haptic output devices  38  may be based on piezoelectric actuators, electromagnetic actuators, electroactive polymers, motors, vibrators, and/or other devices for providing haptic output. 
     Optical components  14  may include displays for displaying images (e.g., images with text, photographs, graphics, movies, etc.). Displays may be organic light-emitting diode displays, displays having pixel arrays formed from crystalline semiconductor light-emitting diodes, liquid crystal displays, electrophoretic displays, and other displays. Components  14  may also include light-emitting diodes and/or other light-emitting devices that have lower resolution than displays. For example, light-emitting diodes may directly supply illumination to an icon-shaped pattern of openings in a layer of material in device  10  or may supply illumination to a light guide layer that provides the illumination to an icon-shaped pattern of openings in a layer of material in device  10 . 
     To power device  10 , device  10  may include a battery, supercapacitor, or other energy storage device  34 . 
     Adjustable fabric  12  may be used to provide a user with haptic output (e.g., by buckling a selected portion of fabric  12  to press against a user&#39;s skin), may be used to tighten and/or loosen a strap, may be used to change the shape of a portion of device  10 , and/or may otherwise be adjusted during operation of device  10 . Fabric  12  may be adjusted by supply electrical signals to conductive strands of material in fabric  12 . The conductive strands may include knots such as mid-strand knots (sometimes referred to as middle-of-strand knots, middle-of-strand loops, etc.). When a current is applied to the knots, magnetic fields are created that give rise to torque and associated movement and change in shape of portions of the knots and associated fabric. For example, portions of fabric  12  may experience changes in tension and may tighten or loosen and/or may buckle or otherwise change shape. 
       FIG. 2  is a perspective view of an illustrative wristwatch device of the type that may include an adjustable strap. Wristwatch device  10  may have a strap such as strap  62  that is formed from adjustable fabric  12 . In the example of  FIG. 2 , the strap is coupled to watch device  30  (e.g., a touch-enabled wristwatch unit having a touch screen, one or more buttons, wireless circuitry for transmitting and receiving wireless information, and/or other components). As shown in  FIG. 2 , the wristwatch may include a clasp such as clasp  60 . Clasp  60  may include magnets, interlocking mechanical features, and/or other clasp structures for securing the ends of the strap together. If desired, clasp  60  may be omitted (e.g., when the strap is elastic). During operation, sensors  26  may gather input through inner and outer surfaces of strap  62  while input-output devices  16  supply visible output, haptic output, and other output through surfaces  62  of device  10 . Device  30 , which may include circuitry and components for device  10  (see, e.g., the circuitry and components of  FIG. 1 ), may also use sensors such sensors  26  to gather input while using input-output devices such as devices  16  of  FIG. 1  to provide output. 
       FIG. 3  is a side view of an illustrative device  10  in a configuration in which device  10  is a strap configured to be worn on a user&#39;s wrist or other body part. The strap may be formed from adjustable fabric  12 . An optional device such as device  10  of  FIG. 2  may, if desired, be coupled to the strap. Control circuitry  24  may be incorporated into device  10  (e.g., in fabric  12 ) to control the shape of adjustable fabric  12  during operation. For example, control circuitry  24  can apply current to conductive strands of material in fabric  12  to cause fabric  12  to contract inwardly (e.g., to radially contract) in directions  70  (e.g., to grasp onto a user&#39;s body so that a blood pressure sensor in sensors  26  can make an accurate measurement). Fabric  12  can also be adjusted by control circuitry  24  so that a portion of fabric  12  forms an inwardly directed protrusion such as protrusion  72  or an outwardly directed protrusion such as protrusion  74 . Protrusion  72  may provide haptic output to a user&#39;s wrist or other body part on which device  10  is being worn. Protrusion  74  may provide haptic output to a user&#39;s finger such as finger  76 . If desired, a touch sensor or other input device and a visual output device (e.g., a display, light-emitting diode(s), etc.) can provide visual output in a portion of device  10  that overlaps a haptic output region (e.g., to implement a button that is illuminated with an icon or other label and that provides haptic feedback when selected). 
     Fabric  12  may be woven fabric, knitted fabric, fabric formed by braiding, and/or other suitable fabric. With one suitable arrangement, which may sometimes be described herein as an example, fabric  12  may be woven fabric such as fabric  12  of  FIG. 4 . As shown in  FIG. 4 , fabric  12  may include intertwined strands of material such as strands  20  (e.g., warp strands  20 A and weft strands  20 B). In the illustrative configuration of  FIG. 4 , fabric  12  has a single layer of woven strands  20 . Multi-layer fabric constructions may be used for fabric  12  if desired. 
     The strands of material in fabric  12  may be single-filament strands (sometimes referred to as fibers or monofilaments), may be yarns or other strands that have been formed by intertwining multiple filaments (multiple monofilaments) of material together, or may be other types of strands. Strands  20  in fabric  12  may include insulating strands and conductive strands. Conductive strands may include bare wires and/or insulated wires. Conductive strands may also be formed from insulating strands covered with metal coatings and strands formed from three or more layers (cores, intermediate layers, and one or more outer layers each of which may be insulating and/or conductive). Strands  20  may be 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 yarns may be formed from a bundle of bare metal wires, metal wire intertwined with insulating monofilaments, and/or other conductive strands. Solder, welds, crimped connections, conductive adhesive connections, and/or other connections may be used to electrically and/or mechanically attach circuitry to strands in fabric  12 . 
     As shown in the illustrative configuration of  FIG. 5 , fabric  12  may have strands  20  that intersect at nodes  78 . Nodes  78  may include knots (e.g., loops of conductive strands that are intertwined in a secure fashion to prevent unraveling) and may include other structures that can be adjusted by selective application of electrical signals (e.g., currents) by control circuitry  24 . Each nodes  78  may, as an example, include one or more knots formed in the middle of a strand  20  (sometimes referred to as mid-strand knots, mid-strand loops, or middle-of-strand loop knots). If desired, nodes  78  may be formed by knots (e.g., mid-strand knots) associated with multiple strands (e.g., two or more intersecting strands may be used to form mid-strand knots at a given node). By applying signals to various strands  20 , the knots can be used to generate magnetic fields that, in turn, create forces (e.g., torque that tends to twist the knots) and thereby adjust tension in the strands. By adjusting fabric tension at various locations within fabric  12 , fabric  12  can be caused to contract globally (e.g., to tighten a band about a user&#39;s wrist) may be caused to relax globally (e.g., to loosen a band), may be caused to fold in an accordion pattern (e.g., to tighten a band by bucking upwards and downwards in alternating rows or columns of nodes), may be caused to protrude or create a recess in one or more locations on fabric  12 , may be caused to vibrate, and/or may otherwise be directed to move and change shape. 
       FIG. 6  is a perspective view of an illustrative strand with interacting loops showing how magnetic fields can be adjusted to adjust tension in the strand. When a current is applied through strand  20  of  FIG. 6  by control circuitry  24 , a first set of loops create magnetic field B 1  and a second set of loops create magnetic field B 2 . Fields B 1  and B 2  will tend to orient in the same direction, which adjusts the tension in strand  20  along its length. To ensure that the loops of strand  20  remain in place in fabric  12 , these loops may form part of a mid-strand knot (e.g., a knot at a node  78 ). 
     An illustrative strand with a node  78  that has been formed from a mid-strand knot (mid-strand loop) is shown in  FIG. 7 . The illustrative mid-strand knot formed in  FIG. 7  is an alpine butterfly loop. Other knot types may be used, if desired. For example, node  78  may be formed from a knot in strand  20  such as a figure eight directional knot, a bowline on a bight knot, a double alpine butterfly loop knot, a dropper loop knot, a figure eight double loop knot, a figure eight follow through knot, a handcuff knot, an a Spanish bowline knot (as examples). 
     As shown schematically in  FIG. 8 , a given strand  20  in fabric  12  may have a knot forming node  78  that creates torque and thereby rotates in a first direction such as illustrative direction  82  when current is driven through the strand. 
     As shown in  FIG. 9 , two strands  20  (e.g., strands  20 - 1  and  20 - 2 ) that intersect at a node  78  may have respective mid-strand knot portions that are configured to create, respectively, torque and rotation in directions  84  and  86 . Depending on the relative currents driven through strands  20 - 1  and  20 - 2 , the torques produced by the first and second knot portions may tend to add to each other or may tend to cancel each other. 
     If desired, electrical components (e.g., input-output devices  16 ) can be incorporated into mid-strand knots (e.g., at nodes  78 ) and/or may otherwise be coupled to strands  20  (e.g., electrical components may be coupled to conductive strands using solder or other conductive connections at locations in fabric  12  such as at nodes  78 ).  FIG. 10  shows how mid-strand knots and/or electrical components (e.g., input-output devices  16 ) may be located at strand intersection points (e.g., nodes  78 ) and/or at strand locations between strand intersections (see, e.g., illustrative nodes  90 ). 
     During operation, control circuitry  24  can control current flow through horizontal strands, vertical strands, and/or other conductive strands in fabric  12 . Solder and/or other electrical connections (shorts) can be created between overlapping conductive strands  20 . In this way, current paths such as the illustrative path of current I in  FIG. 10  may be created to control the current through mid-strand knots and/or electrical components at locations such as nodes  78  and/or nodes  90 .  FIG. 11  shows how fabric  12  may include strands  20  that run diagonally through fabric  12  (e.g., fabric  12  may include diagonal strands  20  in addition to orthogonal warp and weft strands). The strands of  FIGS. 10 and 11  may be provided with control signals in any suitable patterns. For example, the strands in even rows of fabric  12  may receive positive current while the strands in odd rows of fabric  12  may receive negative current, while intersecting strands in even and/or odd columns allow current to flow between rows (as an example). 
     Magnetic materials (e.g., iron or other materials) can be incorporated into fabric  12 . For example, a magnetizable material such as iron may be located at each node  78 . When current is applied through a loop that runs around an iron member, the loop may serve as an electromagnet and may repel and/or attract other magnetic material, permanent magnets, and/or electromagnets. In some arrangements, an iron bar or other member formed form magnetic material can be magnetized by application of current through a strand  20  that loops around that member. The resulting magnet formed from the iron bar or other magnetic material may then magnetically interact with structures formed from magnetic materials such as electromagnets, permanent magnets, etc. In this way, current can be applied to a node  78  to create a magnet (e.g., by magnetizing an iron bar) and this magnet will persist after the current is removed. This allows the torque produced by the magnet (and its interactions with nearby objects) to persist, even though no current is being actively driven through the strand. This arrangement mat thereby help to reduce power consumption. 
       FIG. 12  shows an illustrative node  78  with first and second magnetic members  92 A and  92 B, respectively. Members  92 A and  92 B may be wound with loops of first strand  20 - 1  and second strand  20 - 2 , respectively. Adhesive, a knot (e.g., a mid-strand knot formed by strand  20 - 1  and/or  20 - 3 ), a clip, a hinged structure, or other coupling mechanisms may be used in securing members  92 A and  92  within node  78 . These securing mechanisms may allow members  92 A and  92 B to reorient with respect to each other and thereby adjust tension in fabric  12 . 
     If desired, additional strands such as illustrative strand  20 - 3  may be coupled to members  92 A and  92 B. Additional strands such as strand  20 - 3  may be insulating and/or may be conductive. Optional strand  20 - 3  may, as an example, have a first portion that is coupled to a first side of node  78  and a second portion that is coupled to a second side of node  78 . By applying current through strands  20 - 1  and  20 - 2 , members  92 A and  92 B (e.g., iron bars or other magnetizable magnetic core members) can be provided with magnetic poles that repel one another (see, e.g.,  FIG. 13  in which a gap G is created separating members  92 A and  92 B), that attract each other so that members  92 A and  92 B lie side by side ( FIG. 14 ), and/or that attract each other so that members  92 A and  92 B lie end to end ( FIG. 15 ). Other illustrative configurations for node  78  can be created if desired. Each different configuration for members  92 A and  92 B may create different tensions on strands  20 - 1 ,  20 - 2 , and optional additional strand(s) coupled to node  78  such as strand  20 - 3 . 
     As shown in  FIG. 16 , device  10  may have a source of magnetic field such as magnetic field source  96 . Magnetic field source  96  may be formed from a magnetized magnetic layer (e.g., a sheet magnet), a permanent magnet, an electromagnet, bar magnets, and/or other sources of fixed and/or time-varying magnetic field to be applied to fabric  12  (e.g., globally and/or in selected locations of fabric  12 ). Magnetic field source  96  may provide a magnetic field such as magnetic field  98  that interacts with electromagnets and/or permanent magnets formed at each node  78 . As an example, node  78  may include a magnetic structure (e.g., a member such as member  92  formed from magnetic material) and this magnetic structure may be provided with a magnetic field by applying signals to the strand(s) of that node that interacts with magnetic field  98 . 
     Strands  20  such as strands  20 - 1  and  20 - 2  may be looped about each other and/or about magnetic structure  92 . For example, strand  20 - 1  may form one or more loops on portion  92 B of member  92  and strand  20 - 2  may form one or more loops on portion  92 A of member  92 . Member  92  may be a single piece of material (e.g., an iron member such as an iron bead, etc.) and/or may be formed from multiple pieces of material that are joined together. For example, portions  92 A and  92 B may be coupled together at optional coupling  94  (e.g., using a hinge, a sliding coupling structure, or other coupling mechanism). When current is applied to one or more strands  20  in fabric  12  such as strands  20 - 1  and  20 - 2  of  FIG. 16 , magnetic field will be created that will cause member  92  to move relative to magnetic field  98 . The signals applied to strands  20  by control circuitry  24  can be controlled in this way to adjust the resulting tension of strands  20 . Tension can be controlled in fabric  12  along lines of nodes  78  or other regions of fabric  12 , on selected individual nodes  78 , or on all of fabric  12  globally. 
     In some configurations, some or all of member  92  may be magnetized by application of current to stands  30 . In this type of arrangement, power can be conserved, because each node  78  can retain a desired amount of magnetization after the magnetizing current has been removed. In this state, a permanent magnet will be formed at each node  78  that experiences force due to its interaction with magnetic field  98 . When it is desired to remove a permanent magnet that has been formed in a given member  92 , the polarity of the applied current can be reversed. 
       FIG. 17  shows how gating device(s) (sometimes referred to as gating circuitry) may be incorporated into fabric  12  and/or used with fabric  12  to adjust the application of signals to nodes  78 . Gating devices  100  (e.g., photodiodes, phototransistors, transistors, transistor-based circuits, circuits with force transducers, optical transducers, and/or other circuitry) can be configured to adjust signals applied to each node  78  based on input  102  (e.g., based on optical signals, based on electrical control signals from control circuitry  24 , based on forces applied to force-transducing gating devices, etc.). Consider, as an example, a scenario in an array of gating devices  100  is associated with an array of corresponding nodes  78 . Patterned input (optical, electrical, force, etc.) can be applied to gating devices  100  across fabric  12 . In response, each gating device  100  may supply a corresponding control signal to a respective node  78 . The knots and/or other structures at each node will cause strands  20  near each node to be tensioned by a corresponding amount, thereby causing fabric  12  to change tension and/or shape in a desired pattern. 
     Fabric  12  may, if desired, include one or more fabric layers (e.g., fabric  12  may be a three-dimensional fabric having at least two layers, at least three layers, at least four layers, and/or other number of layers). An illustrative three-dimensional fabric in which strands  20 I are configured to extend between respective fabric layers  12 - 1  and  12 - 2  is shown in  FIG. 18 . Strands  20 I may carry electrical signals and/or may include insulating strands. Each node  78  may include a mid-strand knot and/or other structures that allow node  78  to apply controllable amounts of tension to associated strands  20 . 
     As fabric  12  is tensioned in various locations and changes shape, it may be desirable to provide control circuitry  24  with feedback indicative of the amount of induced tension and/or shape change. If desired, sensors may be incorporated into fabric  12  to provide control circuitry  24  with information on the tension and shape of fabric  12 . 
     With one illustrative configuration, fiber-based sensing systems may be used to monitor fabric  12 . As shown in  FIG. 19 , an optical fiber such as optical fiber  122  may be provided with gratings  124 . Fiber  122  may be incorporated into fabric  12  with other strands  20 . Fiber-optic sensing circuitry  120  may include a laser or other light source that emits light into fiber  122  (sometimes referred to as an optically transparent strand or light guiding strand). Fiber-optic sensing circuitry  120  may also include a light detector that receives emitted light that has been received at circuitry  120  after being reflected backwards towards circuitry  120  from gratings  124 . By analyzing the reflected light (e.g., for frequency, intensity, etc.), fiber optic sensing circuitry  120  can measure bending in fiber  122 . one or more optically transparent strands  20  such as illustrative fiber  122  can be incorporated into fabric  12 , so that fiber optic sensing circuitry  120  can measure the shape of fabric  12  in two dimensions. 
     Sensing circuitry for gathering feedback on the state of fabric  12  can also be based on force sensors such as force-sensitive resistors. An illustrative force sensitive resistor circuit for measuring the state of fabric  12  is shown is shown in  FIG. 21 . As shown in  FIG. 21 , force sensing resistor  126  may be incorporated into fabric  12  (e.g., by coupling one or more strands  20  to resistor  126 , by incorporating resistors  126  into knots and/or other structures at nodes  78 , by including resistors such as resistor  126  in nodes  90 , etc.). As tension is created in portions of fabric  12 , the resistance of resistor  126  changes and this change in resistance is measured by resistance measurement circuitry  128 . 
       FIG. 21  shows how device  10  may include a force sensing arrangement such as a strain gauge or other force sensor that measures tension in fabric  12 . Strain gauge  130  may be directly or indirectly coupled to strands  20  in fabric  12 . As fabric  12  is tensioned and/or changes shape, changes in force may be produced at strain gauge  130 . Control circuitry  24  can use these strain gauge measurements, for example, to determine how tightly a fabric strap has been tensioned about a user&#39;s wrist. 
     If desired, control circuitry  24  can apply alternating-current signals (e.g., control signals and/or sensing signals) to conductive strands in fabric  12  while measuring the impedance of these conductive strands. The impedance of the conductive strands may be affected by tension (e.g., due to changes in knot shape, fabric buckling, and/or other changes in the conductive strands). By monitoring the impedance of the conductive strands in fabric  12 , control circuitry  24  can gather information on the state of fabric  12  (e.g., feedback associated with bending, tension, movement of strands, etc.). 
     Feedback on force, bending, movement, and/or other status information on fabric  12  and other portions of device  10  may, in general, be gathered using any suitable sensors  26 . These sensors may be located in fabric  12 , may be coupled directly to fabric  12  with adhesive or other coupling mechanisms, and/or may be coupled to fabric  12  indirectly. The use of optical measurement circuits such as the optical fiber force and bending sensor arrangement of  FIG. 19 , the force-sensitive resistor sensing arrangement of  FIG. 20 , and the strain gauge sensing system of  FIG. 21  are illustrative. Feedback measurements can be used to form a closed-loop control system in device  10  and/or to gather user input or other input (e.g., input on movement of body parts coupled to fabric  12 , input on movement of a button region in fabric  12  that is being pressed by a finger or other external object, etc.). 
     During operation, control circuitry  24  may apply signals (e.g., currents) to conductive strands among strands  20  in fabric  12  to selectively adjust tension in fabric  12  and thereby selectively adjust the shape and other properties of fabric  12  (e.g., by selectively buckling fabric  12 , by tightening a strap or other structure formed from fabric  12 , by causing a portion of fabric  12  to protrude, and/or by otherwise adjusting fabric attributes such as tension, movement, position, shape, etc.). In some situations, tension is created in a knot in a conductive strand by passing current through that conductive strand and knot. In other situations, multiple strands are used in forming knots (e.g., from intertwined loops of material at a strand intersection location) and tension is adjusted by adjusting multiple currents through multiple respective strands. 
     The magnetism of a magnet embedded in a mid-strand knot can be selectively adjusted. For example, a signal can be passed through a conductive strand to magnetize an iron bar or other member formed of magnetizable material. Nodes at intersections between conductive strands can contain multiple interacting magnetic members that can be selectively magnetized. Magnetized magnetic members may also interact with magnetic fields from magnetic field sources that supply static and/or dynamic magnetic fields (globally and/or locally). The magnetic field source may include electromagnets and/or permanent magnets. 
     Knots can be formed at nodes where two or more conductive strands cross. Insulating strands of material can be coupled to the same nodes. For example, a conductive strand with a mid-strand knot can be used to selectively apply torque to an insulating strand that passes through the same node as the mid-strand knot (e.g., the insulating strand may pass through the mid-strand knot and may form a portion of the mid-strand knot). 
     Conductive strands (e.g., wires) can be knotted to provide a fabric with mid-strand knots that enable prehensile articulation of all or parts of the fabric. When a strap or other fabric-based structure is tightened (e.g., about a user&#39;s arm, wrist, head, finger, or other body part), activities such as gathering blood pressure measurements with a blood pressure sensor in sensors  26  can be facilitated). To maximize the grasping abilities of fabric  12  (e.g., the ability for fabric  12  to perform prehensile articulation), mid-strand knots can be formed at locations of fabric  12  that collectively allow fabric  12  to be constricted and expanded in response to signals from control circuitry  24 . In some configurations, knots may be formed at every (or nearly every) intersection between conductive warp and weft strands. In other configurations, fabric  12  may have a sparser pattern of knots. Light-emitting diodes or other light-emitting components in optical components  14  of input-output devices  16  may be incorporated into fabric  12  (e.g., to form an array of pixels in a display or other output device). Control circuitry  24  can apply signals to the knots in patterns that encourage buckling (e.g., buckling in a region of fabric  12  that overlaps a visual output region where pixels are providing visual). For example, odd knots in each row may be provided with signals that cause the knots to increase tension, whereas even knots in that row may be provided with signals that cause the knots to decrease tension. This type of arrangement may help form fabric  12  into an accordion shape and thereby facilitate tightening of fabric  12  around a user body part of other object. 
     In arrangements in which multiple strands contribute to portions of a common mid-strand knot, the currents applied to the strands may, respectively, add to or subtract from the tension produced at the knot. For example, fabric in which a current-carrying strand with a knot is tied around another current-carrying strand with a knot can be used to add or subtract tension in either strand and/or associated strands (e.g., insulating strands intertwined with the current-carrying strands). 
     Fabric  12  may include current-carrying strands with knots woven in one or more directions within fabric  12 . During operation, control circuitry  24  may be used to apply currents to the knots dynamically to dynamically control the shape (and tension, motion, etc.) of fabric  12 . 
     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: 20180521
Publication Date: 20200218
Grant Date: 20200218
Priority Date: 20180521
Inventors: SALADA, MARK A.
BEYHS, MICHAEL J.
Assignee: APPLE INC
CPC Classifications: [{"code": "A61B2562/0214", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B2562/0204", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/681", "inventive": true, "first": true, "tree": "[]"}, {"code": "A61B5/486", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/1118", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B2562/0219", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/14542", "inventive": false, "first": false, "tree": "[]"}, {"code": "D03D1/0088", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/681", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B6/02057", "inventive": false, "first": false, "tree": "[]"}, {"code": "D03D13/004", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/6843", "inventive": true, "first": true, "tree": "[]"}, {"code": "A61B5/742", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/742", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B6/02057", "inventive": false, "first": false, "tree": "[]"}, {"code": "D03D13/004", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D2700/0174", "inventive": false, "first": false, "tree": "[]"}, {"code": "D03D2700/0166", "inventive": false, "first": false, "tree": "[]"}, {"code": "D03D1/0088", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/6843", "inventive": true, "first": true, "tree": "[]"}, {"code": "A61B5/681", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D15/547", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D15/547", "inventive": true, "first": false, "tree": "[]"}, {"code": "D03D15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "A61B5/389", "inventive": false, "first": false, "tree": "[]"}, {"code": "A61B5/318", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 69528166