PATENT DOCUMENT

Publication Number: US-9979259-B2
Application Number: US-201514837924-A
Country: US
Kind Code: B2

Title: Electromagnetic levitator

Abstract:
A levitator is disclosed. The levitator may include a repulsion wire coil having a vertical coil axis, a position control wire coil having a vertical coil axis, a rotation control wire coil having a horizontal coil axis, and a controller coupled to each of the repulsion wire coil, position wire coil, and rotation wire coil, where the controller is configured to independently control currents provided to each of the repulsion wire coil, position wire coil, and rotation wire coil to levitate an item.

Claims:
What is claimed is: 
     
       1. A levitator, comprising:
 a repulsion wire coil having a vertical coil axis; 
 a position control wire coil having a vertical coil axis; 
 a rotation control wire coil having a horizontal coil axis; and 
 a controller coupled to each of the repulsion wire coil, position wire coil, and rotation wire coil, wherein the controller is configured to independently control currents provided to each of the repulsion wire coil, position wire coil, and rotation wire coil. 
 
     
     
       2. The levitator of  claim 1 , comprising:
 a position sensor that senses the position of a levitated item, 
 wherein the current provided to each of the repulsion wire coil, position wire coil, and rotation wire coil is based on the position of the levitated item. 
 
     
     
       3. The levitator of  claim 2 , wherein the position sensed by the position sensor includes the linear position and angular position of the levitated item. 
     
     
       4. The levitator of  claim 2 , wherein the position sensor is a magnetic field sensor. 
     
     
       5. The levitator of  claim 2 , wherein the position sensor has a variable output based on the strength of an incident magnetic field. 
     
     
       6. The levitator of  claim 2 , wherein the position sensor is a Hall-effect sensor. 
     
     
       7. The levitator of  claim 1 , comprising a plurality of position sensors that together sense the position of a levitated item,
 wherein the current provided to each of the repulsion wire coil, position wire coil, and rotation wire coil is based on the position of the levitated item. 
 
     
     
       8. The levitator of  claim 1 , comprising a plurality of repulsion wire coils, wherein the plurality of repulsion wire coils comprise:
 a single central repulsion coil; and 
 a plurality of peripheral repulsion coils positioned at equal intervals around the central repulsion coil. 
 
     
     
       9. The levitator of  claim 8 , wherein the central repulsion wire coil is circular, and
 wherein each of the peripheral repulsion wire coils has a shape defined by a longer outer arc and a shorter inner arc connected by two side segments. 
 
     
     
       10. The levitator of  claim 8 , wherein each of the plurality of repulsion wire coils has a coil axis parallel to coil axes of the others of the plurality of repulsion wire coils. 
     
     
       11. The levitator of  claim 8 , wherein the plurality of peripheral repulsion coils consists of six peripheral repulsion coils. 
     
     
       12. The levitator of  claim 1 , comprising a plurality of position wire coils, wherein the plurality of position wire coils are disposed above the repulsion wire coil and positioned at equal intervals around a central vertical axis of the levitator. 
     
     
       13. The levitator of  claim 12 , wherein each of the position wire coils has a shape defined by an outer arc and two side segments extending from ends of the outer arc and meeting at an inner apex. 
     
     
       14. The levitator of  claim 12 , wherein each of the plurality of position wire coils has a coil axis parallel to coil axes of the others of the plurality of position wire coils. 
     
     
       15. The levitator of  claim 12 , wherein each of the plurality of position wire coils is positioned opposite another of the plurality of position wire coils. 
     
     
       16. The levitator of  claim 12 , wherein the plurality of peripheral position wire coils consists of four position wire coils. 
     
     
       17. The levitator of  claim 1 , comprising a plurality of rotation wire coils, wherein the plurality of rotation wire coils are positioned at equal intervals around a central vertical axis of the levitator. 
     
     
       18. The levitator of  claim 17 , comprising a plurality of repulsion wire coils positioned at equal intervals around the central vertical axis of the levitator, and
 wherein each of the rotation wire coils is disposed between two adjacent repulsion wire coils. 
 
     
     
       19. The levitator of  claim 17 , wherein each of the plurality of rotation wire coils has a coil axis non-parallel to a coil axis of at least one of the others of the plurality of rotation wire coils. 
     
     
       20. The levitator of  claim 17 , wherein each of the plurality of rotation wire coils has a coil axis tangential to an imaginary circle centered on the central vertical axis of the levitator. 
     
     
       21. The levitator of  claim 17 , wherein each of the plurality of rotation wire coils is positioned opposite another of the plurality of rotation wire coils. 
     
     
       22. The levitator of  claim 1 , comprising:
 a plurality of repulsion wire coils, wherein the plurality of repulsion wire coils comprise:
 a single central repulsion coil centered around a central vertical axis of the levitator; and 
 a plurality of peripheral repulsion coils positioned at equal intervals around the central repulsion coil; 
 
 a plurality of position wire coils, wherein the plurality of position wire coils are disposed above the plurality of repulsion wire coils and positioned at equal intervals around the central vertical axis of the levitator; and 
 a plurality of rotation wire coils, wherein the plurality of rotation wire coils are positioned at equal intervals around the central vertical axis of the levitator. 
 
     
     
       23. The levitator of  claim 22 , wherein the controller is coupled to each of the plurality of repulsion wire coils, each of the plurality of position wire coils, and each of the plurality of rotation wire coils, and
 wherein the controller is configured to independently control current provided to each of the plurality of repulsion wire coils, each of the plurality of position wire coils, and each of the plurality of rotation wire coils. 
 
     
     
       24. The levitator of  claim 23 , comprising:
 a position sensor that senses the position of a levitated item, 
 wherein the currents provided to each of the plurality of repulsion wire coils, each of the plurality of position wire coils, and each of the plurality of rotation wire coils are based on the position of the levitated item. 
 
     
     
       25. A levitation system comprising:
 a levitator comprising wire coils that produce a magnetic field when energized; 
 a magnetic-field-producing item that becomes levitated above the energized wire coils by the magnetic field when the magnetic-field-producing item is disposed above the energized wire coils; and 
 a controller that can dynamically control the position of the magnetic-field-producing item by controlling the current energizing the wire coils, 
 wherein the controller can selectively rotate the magnetic-field-producing item and control its speed of rotation and orientation by controlling the current energizing the coils. 
 
     
     
       26. The levitation system of  claim 25 , wherein the controller can dynamically control the vertical and lateral position of the magnet by controlling the current energizing the coils. 
     
     
       27. The levitation system of  claim 25 , comprising a feedback sensor that can sense the position of the levitated magnetic-field-producing item. 
     
     
       28. The levitation system of  claim 27 , wherein the position sensed by the feedback sensor includes the lateral position, vertical position, and angular position of the levitated magnetic-field-producing item. 
     
     
       29. The levitation system of  claim 25 , wherein the magnetic field produced by the magnetic-field-producing item is irregular about a central axis of the magnetic field produced by the magnetic-field-producing item. 
     
     
       30. The levitation system of  claim 29 , wherein the irregularity in the magnetic field produced by the magnetic-field-producing item is due to an irregularity in the substance of the magnetic-field-producing item. 
     
     
       31. The levitation system of  claim 30 , wherein the magnetic-field-producing item is a permanent magnet, and wherein the irregularity in the substance of the magnetic-field-producing item is a cavity in the permanent magnet or a hole through the permanent magnet. 
     
     
       32. The levitation system of  claim 29 , comprising a feedback sensor that can sense the position of the levitated magnetic-field-producing item at least in part by sensing the irregularity in the magnetic field produced by the magnetic-field-producing item. 
     
     
       33. A method for controlling a levitated item, the method comprising:
 producing a repulsive magnetic field to levitate a magnetic-field-producing item; 
 sensing a rate of rotation of the magnetic-field-producing item; and 
 constraining motion of the magnetic-field-producing item in greater than three degrees of freedom by energizing wire coils with electrical current, 
 wherein constraining motion of the magnetic-field-producing item comprises rotating the magnetic-field-producing item at a controlled rate. 
 
     
     
       34. The method of  claim 33 , wherein constraining motion of the magnetic-field-producing item comprises moving the magnetic-field-producing item vertically or laterally to a desired position. 
     
     
       35. The method of  claim 33 , comprising:
 sensing a position and orientation of the magnetic-field-producing item; 
 determining if the position and orientation of the magnetic-field-producing item deviate from a target position and orientation; and 
 adjusting the amount of electrical current energizing the wire coils to move the magnetic-field-producing item to the target position and orientation. 
 
     
     
       36. The method of  claim 33 , comprising:
 determining if a sensed motion characteristic of the magnetic-field-producing item deviates from a target motion for the magnetic-field-producing item; and 
 adjusting the amount of electrical current energizing the wire coils to change the motion of the magnetic-field-producing item to match the target motion. 
 
     
     
       37. The method of  claim 33 , wherein the rate of rotation is sensed by sensing the position of an irregularity in the magnetic field produced by the magnetic-field-producing item. 
     
     
       38. The method of  claim 33 , wherein constraining motion of the magnetic-field-producing item comprises dynamically moving the magnetic-field-producing item in response to an input. 
     
     
       39. The method of  claim 33 , wherein constraining motion of the magnetic-field-producing item comprises at least one of raising the magnetic-field-producing item, lowering the magnetic-field-producing item, oscillating the magnetic-field-producing item by alternatingly raising and lowering the magnetic-field-producing item, or oscillating the magnetic-field-producing item by alternatingly rotating the magnetic-field-producing item in different directions. 
     
     
       40. The method of  claim 33 , wherein constraining motion of the magnetic-field-producing item comprises dynamically moving the magnetic-field-producing item in response to a dynamic input,
 wherein a magnitude of change in motion of the magnetic-field-producing item is proportional to a magnitude of change in the dynamic input. 
 
     
     
       41. The method of  claim 33 , wherein constraining motion of the magnetic-field-producing item comprises dynamically moving the magnetic-field-producing item in response to a dynamic audio input,
 wherein direction and magnitude of motion of the magnetic-field-producing item are based on at least one of melody, pitch, harmony, rhythm, tone, form, tempo, timbre, texture, and dynamics of the audio input. 
 
     
     
       42. A method for producing a control signal using a levitated item, the method comprising:
 sensing a position and orientation of a magnetically-levitated item; 
 sensing a change in the position or orientation of the magnetically-levitated item due to an external force applied to the magnetically-levitated item; 
 generating a control signal based on the change in position or orientation of the magnetically-levitated item; and 
 transmitting the control signal to control a device remote from the magnetically-levitated item and remote from a levitator levitating the magnetically-levitated item. 
 
     
     
       43. The method of  claim 42 , wherein the change in position is a tilting of the magnetically-levitated item. 
     
     
       44. The method of  claim 43 , wherein a control signal instructing a parameter increase is generated in response to tilting of the magnetically-levitated item in a first direction,
 wherein a control signal instructing a parameter decrease is generated in response to tilting of the magnetically-levitated item in a second direction, and 
 wherein the second direction is different from the first direction. 
 
     
     
       45. The method of  claim 42 , wherein the change in position is a rotation of the magnetically-levitated item. 
     
     
       46. The method of  claim 45 , wherein a control signal instructing a parameter increase is generated in response to rotation of the magnetically-levitated item in a first direction,
 wherein a control signal instructing a parameter decrease is generated in response to rotation of the magnetically-levitated item in a second direction, and 
 wherein the second direction is different from the first direction. 
 
     
     
       47. The method of  claim 42 , further comprising resisting the change in position or orientation to provide tactile feedback through the magnetically-levitated item. 
     
     
       48. The method of  claim 47 , wherein the resistance is a constant force opposing the change in position or rotation. 
     
     
       49. The method of  claim 47 , wherein the resistance is a dynamic force increasing in magnitude as the change in position or orientation continues. 
     
     
       50. The method of  claim 47 , wherein the resistance is a pulsing force repeatedly increasing and decreasing in magnitude as the change in position or orientation continues. 
     
     
       51. The method of  claim 42 , wherein the media device is an audio system or a computer, and wherein the magnetically-levitated item acts as a user input to the audio system or computer based on the external applied force.

Description:
FIELD 
     The described embodiments relate generally to systems and devices for levitating objects. More particularly, the present embodiments relate to levitating objects using magnetic fields. 
     BACKGROUND 
     Objects with opposing magnetic fields will repel each other. By positioning one below the other, the top object can be made to levitate above the bottom object by this repulsive force. 
     SUMMARY 
     Some embodiments of the present invention provide a levitator including a repulsion wire coil having a vertical coil axis, a position control wire coil having a vertical coil axis, and a rotation control wire coil having a horizontal coil axis. The levitator may also include a controller coupled to each of the wire coils, to independently control currents provided to each of the wire coils. 
     Some embodiments of the present invention provide a levitation system including a levitator with wire coils that produce a magnetic field when energized. The system may also include a magnetic-field-producing item—like a permanent magnet—that becomes levitated above the energized wire coils by the magnetic field when the magnetic-field-producing item is positioned above the energized wire coils. A controller may dynamically control the vertical and lateral position, and orientation, of the magnet by controlling the current energizing the wire coils. 
     Some embodiments of the present invention provide a method for controlling a levitated item by producing a repulsive magnetic field to levitate a magnetic-field-producing item—like a permanent magnet—, and constraining motion of the magnetic-field-producing item in greater than three degrees of freedom by energizing wire coils with electrical current. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which: 
         FIG. 1  shows a front view of a levitation system according to some embodiments. 
         FIG. 2  shows a partial cross-sectional view of a levitation system according to some embodiments, taken along line  5 - 5 ′ of  FIG. 4 . 
         FIG. 3  shows a perspective view of a levitator according to some embodiments, with a housing thereof shown in phantom. 
         FIG. 4  shows a bottom view of a levitator according to some embodiments. 
         FIG. 5  shows a cross-sectional view of a levitator according to some embodiments, taken along line  5 - 5 ′ of  FIG. 4 . 
         FIG. 6  shows a schematic side view of a levitation system according to some embodiments. 
         FIG. 7  shows a schematic side view of a levitation system according to some embodiments. 
         FIG. 8  shows a perspective view of a levitation system according to some embodiments. 
         FIG. 9  shows a perspective view of a levitation system according to some embodiments. 
         FIG. 10  shows a top view of a levitator according to some embodiments. 
         FIG. 11  shows a bottom view of a levitator according to some embodiments. 
         FIG. 12  shows a perspective view of a levitation system according to some embodiments. 
         FIG. 13  shows a schematic side view of a levitation system according to some embodiments. 
         FIG. 14  shows a top view of a levitation system according to some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to representative embodiments illustrated in the accompanying drawings. It should be understood that the following descriptions are not intended to limit the embodiments to one preferred embodiment. To the contrary, it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the described embodiments as defined by the appended claims. 
     The following disclosure relates to a levitation system that can levitate an item. The levitator of the levitation system may include sensors that can detect the position (including orientation) and motion of the levitated item, and can adjust the position and motion of the levitated item based on its detected position. In this way, the levitated item can be maintained in a desired location even if it is moved (e.g., by an outside force), and/or can be controlled to move. Such movement (or lack thereof) can be predetermined by being preprogrammed into a control system of the levitator, or can be changeable in real time by being controlled by a real-time input such as from a control panel or audio signal. 
     Levitators as described may be used in a retail setting to display items for sale or display. Levitating an item may help bring attention to it and may present it to a consumer in a way that is easy to view and, in some cases, pick up and manipulate. By moving the item with the levitator, a retailer can further make it stand out to a customer (e.g., by bouncing or rotating it) and can better display all sides of the item to the customer. 
     These and other embodiments are discussed below with reference to the figures. However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes only and should not be construed as limiting. 
       FIG. 1  illustrates a levitation system according to some embodiments of the present invention. The levitation system includes an item  100  levitated by a levitator  200 ,  300 . Levitator  200 ,  300  includes a housing  202 ,  302  containing components of levitator  200 ,  300 . The levitation system of  FIG. 1  also includes an enclosure  400  surrounding the levitated item  100 . 
     Levitator  200 ,  300  may emit a magnetic field (e.g., magnetic fields  372 ,  374 ,  376 , and/or  378  (see, e.g.,  FIGS. 12-14 ). Item  100  may be a magnetic-field-producing item that also emit a magnetic field (e.g., magnetic field  370  emitted by item magnet  110  that forms a part of or is otherwise fixed to item  100 ). These magnetic fields may be generated by anything capable of generating a magnetic field, whether permanent or temporary (e.g., a permanent magnet or an electromagnetic coil such as a wire coil that produces a magnetic field when energized (i.e., when an electric current is passed through it)). In some embodiments, item magnet  110  is a permanent magnet. The magnetic field of levitator  200 ,  300  may be oriented in opposition to the magnetic field of item  100 , thereby inducing a repulsive magnetic force between item  100  and levitator  200 ,  300 . When item  100  is positioned above levitator  200 ,  300 , this repulsive force may overcome gravitational force to levitate item  100  above levitator  200 ,  300 , as shown in  FIG. 1 . Levitators  200 ,  300  described herein may be high-powered levitators, capable of levitating heavy items at great distances. For example, overall power consumption of levitator  200 ,  300  may be 15-25 kilowatts (kW) (e.g., 20 kW), and levitator  200 ,  300  may be capable of levitating a 4-5 kilogram item at a height above 50 millimeters at this power consumption. 
     Enclosure  400  may inhibit interference with levitated item  100 . Enclosure  400  may be made of a clear material (e.g., acrylic), so that item  100  can be viewed through it. In some embodiments enclosure  400  is not used. 
       FIGS. 2-5  illustrate a levitation system according to some embodiments of the present invention, including item  100  levitated by levitator  200 . Levitator  200  is shown in cross-section in  FIG. 2 , and may include one or more repulsion magnets  210 , which may be permanent magnets. Levitator  200  may also include one or more position control magnets  220 , which may be electromagnetic coils. Together, permanent repulsion magnets  210  and electromagnetic position control coils  220  generate magnetic fields that act against a magnetic field of item  100  (which may include an item magnet  110  generating item  100 &#39;s magnetic field), to induce magnetic forces that levitate item  100  above levitator  200 . 
     In some embodiments, magnetic axes  211  of permanent repulsion magnets  210  are oriented closer to vertical than horizontal (e.g., vertically as shown in  FIGS. 2-5 ) and permanent repulsion magnets  210  are disposed spaced apart around a center of levitator  200 . In some embodiments, magnetic axes  221  of electromagnetic position control coils  220  are oriented closer to horizontal than vertical (e.g., horizontally as shown in  FIGS. 2-5 ) and electromagnetic position control coils  220  are disposed spaced apart around the center of levitator  200 . Permanent repulsion magnets  210  may provide most of the vertical force levitating item  100 . Vertical component force  282  provided by permanent repulsion magnets  210  is shown schematically in  FIG. 6 . And since permanent repulsion magnets  210  are disposed intermittently about and spaced apart from a center of levitator  200 , the force induced by a first permanent repulsion magnet  210  tends to push item  100  toward the center of levitator (or away from it, depending on the polar orientation of permanent repulsion magnets  210 ), where it is counteracted by the force induced by one or more second permanent repulsion magnets  210  disposed on the other side of levitator  200  from the first (e.g., disposed opposite the first about the center of levitator  200 ). These opposing forces tend to keep item  100  positioned centrally above levitator  200 . 
     Levitator  200  may also control the lateral position or movement of item  100  above levitator  200 . This control may be used to, for example, augment permanent magnets  210  in keeping item  100  centrally positioned, help return item  100  to a desired position after it has been moved (e.g., by an outside force), move item  100  above levitator  200  (e.g., to a different static position, or in a continuous dynamic pattern). Such control may be effected by electromagnetic position control coils  220 . As shown, for example, in  FIG. 3 , electromagnetic position control coils  220  are arranged horizontally in levitator  200 . By controlling current direction through electromagnetic position control coils  220 , the polarity of the generated magnetic field can be set or reversed. For example, all electromagnetic position control coils  220  may be operated to have the same magnetic poles oriented inward, so they are all inducing the same lateral force direction on levitated item  100  (e.g., repulsive force tending to push item  100  toward levitator  200 &#39;s center, or attractive force tending to pull item  100  away from levitator  200 &#39;s center). Whether all attracting or all repelling, forces from all electromagnetic position control coils  220  can be tuned to be relatively equal, thereby cancelling each other out and helping to keep item  100  stationary above the center of levitator  200 . Horizontal component force  286  provided by electromagnetic position control coils  220  is shown schematically in  FIG. 7 . 
     Electromagnetic position control coils  220  may also be used to move item  100  (e.g., laterally above levitator  200 ). For example, one or more first electromagnetic position control coils  220  may be driven with more current than the other, second electromagnetic position control coils  220 , causing a greater repelling (or attracting) force to be induced from those first electromagnetic position control coils  220 . This will cause item  100  to move away from (or toward) first electromagnetic position control coils  220 . Current through electromagnetic position control coils  220  can be varied selectively throughout all electromagnetic position control coils  220  to achieve any desired movement of item  100  above levitator  200  (including, e.g., restorative movement to move item  100  back to a predetermined position when it has been moved out of it, or dynamic patterned movement following real-time or predetermined patterns). 
     Current through electromagnetic position control coils  220  may be controlled by a control system  240 , which may be a part of levitator  200 . Control system  240  may include a main controller  242 , which may include a sub-controller  244 , a position sensor  246 , and a coil circuit  248 . Position sensor  246  may be positioned within levitator  200  below an area in which item  100  is intended to levitate. For example, as shown in  FIGS. 2 and 3 , position sensor  246  is positioned centrally within levitator  200 . Position sensor  246  can sense the position of levitated item  100  relative to levitator  200 , and can send a signal representing that position to sub-controller  244  (which may be, for example, a microcontroller). Position sensor  246  may be, for example, a magnetic-field sensor, such as a Hall-effect sensor, that has a variable output based on the strength of an incident magnetic field. In some embodiments, position sensor  246  may include one or more such sensors arranged in an array on one or more printed circuit boards. 
     Based on the position signal(s) from position sensor  246 , coil circuit  248  can send or adjust the amount and/or direction of current through each electromagnetic position control coil  220  to adjust the position of item  100  as described above. Control system  240  thus creates a feedback loop where the position of item  100  is monitored and adjusted as needed to maintain a desired static position or dynamic movement of item  100 . 
     In some embodiments, levitator  200  includes mounting brackets  204  to affix it to a surface (see  FIG. 3 ). In some embodiments permanent repulsion magnets  210  are mounted on magnet mounts  212 , and electromagnetic position control coils  220  are mounted on coil mounts  222 . Magnet mounts  212  and/or coil mounts  222  may be, for example, bolts, screws, or glue). In some embodiments magnet mounts  212  and/or coil mounts  220  are adjustable, in order to move the position of permanent repulsion magnets  210  to adjust their effect on levitated item  100 . For example, where magnet mounts  212  and/or coil mounts  220  are screws, bolts, or other threaded fasteners, turning them in one direction or the other may raise or lower permanent repulsion magnets  210 . 
       FIGS. 8-11  illustrate a levitation system according to some embodiments of the present invention, including item  100  levitated by levitator  300 . Levitator  300  may include one or more electromagnetic repulsion coils  310 , one or more electromagnetic position control coils  320 , and one or more electromagnetic rotation control coils  330 . Coils  310 ,  320 , and  330  may be formed of wire wrapped together in a coiled configuration. Coils  310 ,  320 , and  330  may be contained within a housing  302  of levitator  300  (see  FIG. 1 ; housing  302  is omitted from other views for clarity of depiction). Together, these three coil types can be controlled to control or influence the position and movement of levitated item  100  in 6 degrees of freedom. To control the effect of its coils, levitator  300  in some embodiments includes a control system  340 . Control system  340  may control the amount and direction of electrical current through each of coils  310 ,  320 ,  330 , thereby controlling the position and/or motion of levitated item  100 . This control can constrain motion of item  100  to keep it to a static position, or to dynamically move it (e.g., back to a static position, or consistently with a desired dynamic motion). 
     Electromagnetic repulsion coils  310  may in some embodiments include a central repulsion coil  312  and peripheral repulsion coils  314  disposed radially around central repulsion coil  312  at equal intervals, as shown. For example, in some embodiments levitator  300  may include a single central repulsion coil  310  and six peripheral repulsion coils  314 . In some embodiments the wire used to form electromagnetic coils  310  is copper wire. In some embodiments the wire used to form electromagnetic coils  310  is rectangular wire, to help maximize wire packing efficiency in forming electromagnetic repulsion coils  310  (wire with rectangular cross-section can be wrapped into a coil without space between adjacent turns of the wire), though other forms (e.g., circular) may be used to achieve similar results. In some embodiments the wire used to form electromagnetic coils  310  is electrically insulated with an insulative coating. The insulative coating may be thermally conductive and thermally stable such that it will not break down at high operating temperatures. The insulative coating may be, for example, a bondable thermoplastic film (e.g., polyester amide bindable insulation, or polyurethane-based insulation). The bondable film will bond to the insulative coating on adjacent turns of wire in electromagnetic repulsion coils  310 , thereby helping the coil maintain its form, and support itself. 
     Magnetic axis  313  of central repulsion coil  312  may coincide with a vertical center axis (or z-axis, see  FIG. 9 ) of levitator  300 . Magnetic axes  315  of peripheral repulsion coils  314  may be oriented closer to vertical than horizontal (e.g., parallel to magnetic axis  313  and the z-axis as shown in  FIG. 9 ). In some embodiments, magnetic axis  313  and magnetic axes  315  are all parallel to each other. In some embodiments, central repulsion coil  312  has a circular coil shape, as shown, but it may be other shapes, for example, an oval or square. In some embodiments, peripheral repulsion coils  314  have a coil shape defined by a longer outer arc and a shorter inner arc connected by two side segments, as shown. This may help peripheral repulsion coils  314  to seat closely around a portion of central repulsion coil  312  (e.g., so that a portion of central repulsion coil  312  is within the shorter inner arcs of peripheral repulsion coils  314 ) while still maintaining a roughly circular arrangement of levitator  300  (e.g., by the longer outer arcs being in circular alignment centered on magnetic axis  313  of central repulsion coil  312 ). But peripheral repulsion coils  314  need not have the shape shown; they could, for example, be circular or square. Central repulsion coil  312  may have a central repulsion coil axis  316 , and peripheral repulsion coils  314  may have peripheral repulsion coil axes  317 . Coil axes  316  and  317  may coincide with magnetic axes  313  and  315 , respectively, and/or may have the same positioning as magnetic axes  313  and  315  as described above. 
     Electromagnetic position control coils  320  may in some embodiments include multiple electromagnetic position control coils  320  positioned radially around the center of levitator  300  at equal intervals, as shown (e.g., around magnetic axis  313  of central repulsion coil  312 , of the z-axis as shown in  FIG. 9 ). For example, levitator  300  may include four electromagnetic position control coils  320 , as shown, for example, in  FIGS. 8 and 10 . Each electromagnetic position control coil  320  may be positioned opposite another electromagnetic position control coil  320  about a central vertical axis  301  of levitator  300 . Electromagnetic position control coils  320  may be formed from wire (including insulation) having the same or similar properties as described above for electromagnetic repulsion coils  310 . 
     Magnetic axes  321  of electromagnetic position control coils  320  may be oriented closer to vertical than horizontal (e.g., parallel to magnetic axis  313  and the z-axis as shown in  FIG. 9 ). In some embodiments, magnetic axes  321  are all parallel to each other. In some embodiments, magnetic axes  321  are all parallel to magnetic axes  313  and  315 . In some embodiments, electromagnetic position control coils  320  have a wedge coil shape, defined by an outer arc and two side segments extending from ends of the outer arc and meeting at an inner apex, as shown. This may help electromagnetic position control coils  320  fit closely together and together overlay and enclose a substantial portion (e.g., greater than 50%) of the area occupied and enclosed by electromagnetic repulsion coils  310 . But electromagnetic position control coils  320  need not have the shape shown; they could, for example, be circular or square. Electromagnetic position control coils  320  may have position control coil axes  326 . Coil axes  326  may coincide with magnetic axes  321  and/or may have the same positioning as magnetic axes  321  as described above. 
     Electromagnetic rotation control coils  330  may in some embodiments include multiple electromagnetic rotation control coils  330  positioned radially around the center of levitator  300  at equal intervals, as shown (e.g., around magnetic axis  313  of central repulsion coil  312 , of the z-axis as shown in  FIG. 9 ). For example, levitator  300  may include six electromagnetic rotation control coils  330 , as shown, for example, in  FIGS. 9 and 11 . Electromagnetic rotation control coils  330  may be formed from wire (including insulation) having the same or similar properties as described above for electromagnetic repulsion coils  310 . 
     Magnetic axes  331  of electromagnetic rotation control coils  330  may be oriented closer to horizontal than vertical (e.g., perpendicular to magnetic axis  313  and the z-axis as shown in  FIG. 9 ; parallel to the x-y plane). In some embodiments, magnetic axes  331  are all perpendicular to at least one of magnetic axes  313 ,  315 , and  321 . In some embodiments, electromagnetic rotation control coils  330  have a rectangular shape, defined by four major straight lengths connected at right angles, as shown. This may help electromagnetic rotation control coils fit in between adjacent peripheral repulsion coils  314 : they can wrap around the most portions of adjacent peripheral repulsion coils  314  that are most proximate to each other while keeping close to peripheral repulsion coils  314 , as shown. But electromagnetic rotation control coils need not have the shape shown; they could, for example, be circular or triangular. Electromagnetic rotation control coils  330  may have rotation control coil axes  336 . Coil axes  336  may coincide with magnetic axes  331  and/or may have the same positioning as magnetic axes  331  as described above. 
       FIGS. 12-14  illustrate magnetic fields and forces generated and induced by electromagnetic coils  310 ,  320 , and  330 , and by item magnet  110 . Electromagnetic repulsion coils  310  may provide most of the vertical force levitating item  100 , thereby controlling and having the greatest influence over item magnet  110 &#39;s (and thereby item  100 &#39;s) position and movement in the vertical direction (i.e., along the z-axis). Electromagnetic position control coils  320  may provide most of the horizontal radial force (i.e., force directed toward and away from central vertical axis  301  of levitator  300 ), thereby controlling item  100 &#39;s position and movement in the horizontal plane (i.e., within the x-y plane). Electromagnetic rotation control coils  330  may provide most of the tangential force (i.e., force directed about central vertical axis  301  of levitator  300 ), thereby controlling item  100 &#39;s orientation about central vertical axis  301  of levitator  300 . 
     Together, coils  310 ,  320 , and  330  can also control the pitch, or tilt, of item  100  (e.g., while held at a static orientation by electromagnetic rotation control coils  330 , peripheral repulsion coils  314  on a first side of levitator  300  may be run at a higher current than peripheral repulsion coils  314  on a second, opposite, side of levitator  300 , thereby inducing greater force on item  100  above the first side, causing that side of item  100  to raise higher, tilting item  100 . Electromagnetic position control coils  320  can be run at appropriate currents to maintain item  100  in the intended horizontal position above levitator  300 . 
     Of course, due to the nature of magnetic fields, magnetic fields from any of the described coils may contribute some amount of induced force in directions other than those described, but the effects of all of the coil contributions can be coordinated together to achieve the desired position and/or motion of item  100  through control system  340 , described further below. For example, consider that a force induced by electromagnetic position coils is 80% horizontal radial force and 20% vertical levitating force. That 20% vertical levitating force may help lighten the load that electromagnetic repulsion coils  310  must carry in order to keep item  100  levitated at a desired height, and so electromagnetic repulsion coils  310  may be run at a lower current than would otherwise be needed to maintain that height. 
       FIG. 12  illustrates magnetic fields and forces induced by electromagnetic repulsion coils  310  and electromagnetic position control coils  320  according to some embodiments. In the exemplary embodiment shown in  FIG. 12 , item magnet  110 &#39;s magnetic field is represented by arrows  370 , electromagnetic repulsion coils  310 &#39;s magnetic field is represented by arrow  371 , and electromagnetic position control coils  320 &#39;s magnetic field is represented by arrow  376 . Where the fields cross, force is induced. A repulsion force is induced at  380 , and a position control force is induced at  386 . Since repulsion coil field  371  crosses item magnet field  370  closer to the center of levitator  300  and item magnet  110 , it crosses at an angle with a significant vertical component, thereby inducing a vertical force (e.g., repulsion force  380 ). This may provide the majority of the force used to levitate item  100 , as described above. Since position control coil field  376  crosses item magnet field  370  farther from the center of levitator  300  and item magnet  110 , it crosses at an angle with a significant horizontal component, thereby inducing a horizontal force (e.g., position control force  386 ). This may provide the majority of the force used to control the horizontal position of item  100 , as described above. 
       FIG. 13  represents a single vertical plane of levitator  300  to illustrate schematically some of the magnetic fields and forces induced by electromagnetic repulsion coils  310  and electromagnetic position coils  320  according to some embodiments. Hatching in  FIG. 13  is different for different elements, and does not necessarily indicate different materials. Only a few field lines and forces are illustrated, for exemplary and instructive purposes. One of skill in the art would recognize that the actual magnetic fields generated would be more dense and could take on many different positions and shapes depending on system variables such as character of the coils (e.g., gauge, length, number and arrangement of turns, and coil direction) or item magnet, as well as the magnitude and direction of current running through the coils. 
     Further, the size ratio between the electromagnetic coils (individually or collectively—e.g., repulsion coils  310 ) and item magnet  110  influences the degree of lift and control attributable or attainable from each coil, since the direction of electromagnetic coil electric fields (e.g., repulsion coil fields  371 , position control coil fields  374 , and rotation control coil fields  378  of electromagnetic repulsion coils  310 , electromagnetic position control coils  320 , and electromagnetic rotation control coils  330 ) incident on item magnet field  370  of item magnet  110  depend on the size, shape, and positioning of the electromagnetic coils relative to the size, shape, and positioning of item magnet  110 . 
     As shown, central repulsion coil  312  and peripheral repulsion coils  314  are operated to have a first magnetic polarity, oriented in opposition to the second magnetic polarity of levitated item  100 . This opposition in magnetic polarity provides the magnetic opposition that helps induce the repulsive magnetic forces used to levitate and control the height of levitation of item  100 . As also shown, electromagnetic position control coils  320  are also operated to have the first magnetic polarity. In this operative orientation they can contribute to levitating and controlling the height of levitation of item  100 , and can control the horizontal position and motion of item  100  by providing a lateral repulsive force upon item  100 . The operative orientation of electromagnetic position control coils  320  or subsets thereof can be reversed, however, to control the position (including orientation) of item  100  using attractive forces, or a combination of repulsive and attractive forces. 
     Item magnet  110  generates item magnet field  370 . Central repulsion coil  312  generates central repulsion coil field  372  when energized with current, which interacts with item magnet field  370  to induce central repulsion forces  382  between the two fields. As shown, central repulsion forces  382  have vertical components, which may provide and/or contribute to levitation of item  100  (which includes item magnet  110 ) by overcoming gravitational force acting on item  100 . Magnetic fields and forces discussed herein are shown along a few particular lines for clarity of depiction. One of skill in the art would understand that the magnetic fields and forces described radiate infinitely in expanding circles from their origins, and that the strongest forces induced occur where fields intersect at 90-degree angles. 
     Peripheral repulsion coils  314  generate peripheral repulsion coil fields  374  when energized with current, which interact with item magnet field  370  to induce peripheral repulsion forces  384  between item magnet field  370  and peripheral repulsion coil fields  374 . As shown, peripheral repulsion forces  384  have vertical components, which may provide and/or contribute to levitation of item  100  by overcoming gravitational force acting on item  100 . In some embodiments, central repulsion coil  312 , peripheral repulsion coils  314 , or both, may have a current density of 4-7 amps per square millimeter (A/mm 2 ) (e.g., 5.5-6 A/mm 2 ). 
     Central repulsion coil  312  and peripheral repulsion coils  314  may work together to levitate item  100  by the combined vertical magnitude of central repulsion forces  382  and peripheral repulsion forces  384 . For example, central repulsion coil  312  (which may be formed of 12 AWG wire having a direct current resistance of 0.71) may be energized with current up to 18.3 amperes to produce a force of up to 52 Newtons on item magnet  110 , and peripheral repulsion coils  314  (which may be formed of 12 AWG wire having a direct current resistance of 0.45) may be energized with current up to 18.3 amperes to each produce a force up to 3 Newtons on item magnet  110 , for a total of 70 Newtons of upward force levitating item  110 . (Peripheral repulsion coils  314  each contributes less force to item magnet  110  since they are farther from item magnet  110  when it is positioned centrally above levitator  300 .) Of course, these values can change depending on the position of item magnet  110  and the amount of current provided to each coil by control system  340 . In some embodiments, the capacity of the system to reach higher current and force values may be improved by its incorporation of a cooling system to draw generated heat from out of the system. The cooling system may use a substance other than air to effect such cooling (e.g., water or liquid nitrogen). This can allow system components to operate at higher current and force values without exceeding temperature thresholds. 
     Electromagnetic position control coil  320  generated position control coil field  376 , which interacts with item magnet field  370  to induce position control forces  386  between the two fields. As shown, position control forces  386  have horizontal components acting on magnet field  370  from both sides, which may be used individually or in tandem to push and/or pull item  100  horizontally toward or away from the outer edges of levitator  300 . Since position control coils  320  are wedge-shaped in this embodiment, their magnetic field axes  321  are positioned more toward their outer arcs than their inner apices. This can help position control coil field have more of a horizontal impact on item magnet field  370  by positioning the field&#39;s origin farther away from central magnetic axis  313 , while maintaining a compact footprint for levitator  300 . 
     As shown in  FIG. 13 , peripheral repulsion forces  384  can have a horizontal component acting on item magnet field  370 . In some embodiments, in addition to their role in providing vertical repulsive force as described, peripheral repulsion coils  314  can provide position control of item  100  in the same manner as described for position control force  386 , using the horizontal components of peripheral repulsion forces  384 . In such embodiments, separate position control coils may be omitted. This may lead to a more compact or economical levitator  300 . Embodiments including electromagnetic position control coils  320  may have increased control over movement and position of item  100  due to the independent control over peripheral repulsion coil field  374  and position control coil field  376  (and thus peripheral repulsion force  384  and position control force  386 . 
       FIG. 14  represents a top view of levitator  300  to illustrate schematically some of the magnetic fields and forces induced by electromagnetic rotation control coils  330  according to some embodiments. Certain parts of levitator  300  are broken away for clarity, to make electromagnetic rotation control coils  330  more visible. Only a few field lines and forces are illustrated, for exemplary and instructive purposes. One of skill in the art would recognize that the actual magnetic fields generated would be more dense and could take on many different positions and shapes depending on system variables such as character of the coils (e.g., gauge, length, number and arrangement of turns, and coil direction) or item magnet, as well as the magnitude and direction of current running through the coils. 
     As shown, electromagnetic rotation control coils  330  are operated to have a first magnetic polarity oriented in the same direction around central vertical axis  301  of levitator  300  coincident with magnetic axis  313 . In this operative orientation they all induce forces in the same angular direction—clockwise as viewed in  FIG. 14 —thereby causing or promoting rotation of item  100  (including item magnet  110 ) in the clockwise direction. The operative orientation of electromagnetic rotation control coils  330  or subsets thereof can be reversed, however, to induce forces in the opposite angular direction—counterclockwise as viewed in  FIG. 14 —thereby causing or promoting rotation of item  100  in the counterclockwise direction. In some cases, the operative orientation of only a subset of electromagnetic rotation control coils  330  may be reversed to run in the counterclockwise direction while others remain operating in the clockwise direction, thereby inducing angular forces in opposition to each other, which may be used to more precisely control the orientation of item  100 , as described in more detail below with respect to control system  340 . 
     As shown in  FIG. 14 , electromagnetic rotation control coils  330  generate rotation control coil fields  378 , which interact with item magnet field  370  to induce rotation control forces  388  between item magnet field  370  and rotation control coil fields  378 . As shown, Rotation control forces  388  have tangential components (to a circle about axis  313 ), or components that cross item magnet field  370  perpendicularly, which may provide and/or contribute to rotation of item  100  by counteracting or overcoming some or all forces in a contrary direction due to, for example, momentum, inertia, or friction. 
     As item magnet  110  is levitated, its position and orientation are monitored and controlled by a control system  340 . Control system  340  may include a main controller  342 , a controller  344 , position sensor  346  and a coil circuit  348 . In some embodiments one of main controller  324  and controller  344  may be omitted or both may be formed together in the same controller. In some embodiments one or both of main controller  324  and controller  344  may be a microcontroller. 
     In some embodiments, as shown, for example, in  FIGS. 9 and 10 , control system  340   346  may include multiple separate position sensors  346  arranged about a center of levitator  300 . Position sensors  346  can sense the position (including orientation) of levitated item  100  relative to levitator  300 , and can send a signal representing that position to controller  344  (which may be, for example, a microcontroller). Position sensors  346  may be, for example, magnetic-field sensors, such as Hall-effect sensors, that have a variable output based on the strength of an incident magnetic field. In some embodiments, position sensors  346  may include one or more such sensors arranged in an array on one or more printed circuit boards. In some embodiments, position sensors  346  are arranged within electromagnetic position control coils  320  and above electromagnetic repulsion coils  310  and electromagnetic rotation control coils. In this arrangement, as shown, for example, in  FIG. 8 , no coil passes over a position sensor  346 , thus minimizing potential interference therefrom. In some embodiments, position sensors  346  may be formed as wedge-shaped printed circuit boards to fit efficiently within electromagnetic position control coils  320 . 
     In some embodiments, position sensor  346  may sense the position (including orientation) of item magnet  110  as it is levitated above levitator  300 . In some embodiments, position sensor  346  may sense the position of item magnet  110  in greater than three degrees of freedom, for example, 6 degrees of freedom: translation (linear position) and rotation (angular position) in or about each of the x, y, and z axes. In some embodiments, position sensors  346  can sense translation position along the x, y, and z axes by sensing strength or change in magnetic field due to proximity of item magnet  110  to sensing elements of position sensors  346 . In some embodiments, position sensors  346  can sense rotation position about the x, y, and z axes by sensing the position of an irregularity  112  in item magnet  110 . Irregularity  112  may be, for example, a discontinuity in item magnet  110  (e.g., a hole through item magnet  110 , a cavity in item magnet  110 , a divot in item magnet  110 ), a protrusion of item magnet  110 &#39;s surface, an area of higher or lower density than the balance of item magnet  110 , or an area otherwise having different magnetic properties than the balance of item magnet  110 . Irregularity  112  is positioned offset from the center of item magnet  110 , so that its position is determinative of the orientation of item magnet  110  (and thus item  100 ). Position sensors  346  may sense a change or difference in magnetic field due to irregularity  110 , and from this change or difference control system  340  can determine the position of irregularity  110 , and thus the orientation (rotation position) of item magnet  110  about the x, y, and z axes (see, e.g.,  FIGS. 9 and 14 ). 
     Position sensors  346  can thus sense the position of item magnet  110 . By sensing the position and its change over time, position sensors  346  can sense both position and motion (static and dynamic) of item magnet  110 . Position sensors  346  can send signals representative of the position and motion characteristics (e.g., location, magnitude, angle, rate of change, direction of motion) to controller  344  (see  FIG. 8 ), which in turn may control or change the magnitude and/or direction of current through any of the electromagnetic coils of levitator  300  (e.g., electromagnetic repulsion coils  310 , electromagnetic position control coils  320 , electromagnetic rotation control coils  330 ) to constrain motion (e.g., by maintaining or changing the position or motion) of item magnet  110  in six degrees of freedom as described above. For example, controller  344  may maintain or adjust the current through the electromagnetic coils individually through a coil circuit  348 , which may include, for example, one or more H-bridges or other electronic circuits that enable voltage to be applied across a load in either direction. Coil circuit  348  may be connected individually to each of coils  310 ,  320 ,  330  by coil leads, which are wires (which may be portions of the wires forming each of wire coils  310 ,  320 ,  330 ) that extend from each of coils  310 ,  320 , and  330  and connect to control system  340 , as shown, for example, in  FIGS. 8 and 10 .  FIG. 8  shows only a single set of coil leads for each coil: repulsion coil leads  362 , position coil leads  364 , and rotation coil leads  366 . But it should be understood that each coil has its own set of coil leads connected to control system  340  (e.g., to coil circuit  348  or controller  344 ). 
     In an example scenario, control system  340  may be programmed to maintain item magnet  110  in a static position centered two inches above levitator  300 . If position sensors  346  sense that item magnet  110  is centered only one inch above levitator  300  (e.g., due to a weight applied to item magnet  110 ), controller  344  may increase the current through electromagnetic repulsion coils  310  to increase repulsion force  380  until item magnet  110  rises to two inches above levitator  300 . In a further example scenario, control system  340  may be programmed to maintain item magnet  110  centered two inches above levitator  300 , rotating clockwise about the vertical z-axis at a rate of two revolutions per minute. If position sensors  346  sense that item magnet  110 &#39;s rate of rotation decreases below two revolutions per minute (e.g., due to drag), controller  344  may increase the current through one or more electromagnetic rotation control coils to increase rotation control forces in the clockwise direction. Since item magnet  110  will continue to rotate under its own momentum, controller  344  may send one or more current pulses to generate rotation control force pulses until the desired rotation rate is achieved (here two revolutions per minute). 
     In some scenarios, levitator  300  may be programmed (preprogrammed or programmed in real time) to achieve a desired position (including orientation) or motion characteristic (e.g., rate or direction of movement) of item  100 . These desired characteristics may be defined by target values (which may be ranges), and if item magnet  100  deviates from the target by greater than a predetermined amount, controller  344  may reset its position to the target value by adjusting the magnitude and/or direction of current through any or all of electromagnetic coils  310 ,  320 , and  330 . 
     Because electromagnetic coils  310 ,  320 , and  330  of levitator  300  can be independently controlled and together can be driven to control the position and motion of item magnet  110  in 6 degrees of freedom, levitator  300  can maintain an item in any desired position or orientation, statically or dynamically. This makes it well-suited to levitate items  100  that are asymmetric—for example those that have uneven weight distribution. Since levitator  300  can tilt item magnet  110 , it can also tilt item  100  that contains item magnet  110 . So if item  100  were, for example, a watch having an asymmetric shape and uneven weight distribution, levitator  300  could still levitate it at a desired angle (e.g., to present the watch face tilted upward toward a potential viewer or purchaser in a retail setting) by adjusting the magnitude and direction of current through electromagnetic coils  310 ,  320 , and  330 . Or if item  100  were, for example, a cylindrical computer housing having a generally symmetrical shape but an uneven weight distribution (e.g., due to the positioning of internal components), levitator  300  could still levitate it in a vertical position (e.g., to show it as it would sit on a desk) by adjusting the magnitude and direction of current through electromagnetic coils  310 ,  320 , and  330 . 
     In some embodiments, levitator can be driven to levitate a great weight (e.g., 4-5 kilograms) at a great height (e.g., above 50 millimeters). As one of skill in the art would appreciate, these exemplary values scale inversely (e.g., a lower weight can be levitated at a greater height, and at a lower height a higher weight can be levitated). In some embodiments electromagnetic coils  310 ,  320 , and  330  can be driven at a current density of, for example, 4-7 A/mm 2  to provide a magnetic field strong enough to support such weight at such substantial height. In some embodiments, overall power consumption for levitator  300  may be 15-25 kilowatts (kW) (e.g., 20 kW). 
     In some scenarios position sensors  346  may detect that item magnet  100  is no longer present within their detection range, because it has been removed. In some embodiments, in response to a signal from position sensors  346  that item magnet  100  has been removed, control system  340  may power down levitator  300 , and/or may sound an alarm (e.g., to alert a retailer or other person that item  100  has been removed). 
     Levitator  300  is operated at least in part by current provided by a power supply  250  (e.g., from a wall power outlet or other source, see  FIG. 8 ). In the event of an interruption in power provided by power supply  250  (e.g., due to a power failure), levitator  300  may slowly reduce power to electromagnetic coils  310 ,  320 , and  330 , in order to slowly lower item  100  onto the surface of levitator  300 . This avoids abruptly dropping item  100  when power is lost. Levitator  300  may include a backup battery to provide the current to drive coils  310 ,  320 , and  330  at decreasing magnitude while lowering item  100  in the event of power loss at power supply  250 . 
     As described above, levitator  300  can control the position (including orientation) and motion of levitated item  100  and item magnet  110  statically or dynamically by driving electromagnetic coils  310 ,  320 , and  330  at various magnitudes and directions. The position and motion of levitated item  100  and item magnet  110  can at the same time be sensed by position sensors  346 , which send signals indicative of the position and motion to main controller  342 , which, based on the signals, can maintain or adjust the current magnitude and direction of any or all of electromagnetic coils  310 ,  320 , and  330  to maintain or change the position and motion of levitated item  100  and item magnet  110  statically or dynamically. In some embodiments, this feedback loop of control system  340  maintains item  100  in a predetermined position and/or motion. If the item deviates from the predetermined position or motion, the feedback loop senses and corrects it by changing the magnitude and/or direction of current through one or more of electromagnetic coils  310 ,  320 , and  330 . In some embodiments, the position and motion of levitated item  100  is controlled in real time, interactively. For example, main controller  342  may receive an input (e.g., from a user or other outside source) and may adjust the position and/or motion of item  100  based on that input in real time (e.g., by adjusting the magnitude and/or direction of current through any or all of electromagnetic coils  310 ,  320 , and  330 ). 
     For example, a user may input parameters into a control panel of or connected to main controller  342  to move levitated item  100  in any or all of the six degrees of freedom above levitator  300 . Also for example, a microphone or other audio input device may be connected to or part of main controller  342 , and the position and/or motion of levitated item may be controlled (e.g., dynamically changed) based on the audio input received by the microphone or other audio input device. For example, levitated item  100  may be made to “dance” to music sensed by the audio input device. It may oscillate, bounce, rotate, translate, tilt, etc. based on any or all of the melody, pitch, harmony, rhythm, tone, form, tempo, timbre, texture, and dynamics of sensed music or other audio input. In some embodiments, a magnitude of change in motion of levitated item  100  may be proportional to a magnitude of an input (e.g., turning a dial on a control panel may cause item  100  to be raised a distance proportional to the amount the dial is turned; a louder sound or faster tempo may cause a greater change in movement than a quieter sound or slower tempo). 
     In some embodiments, levitator  200 ,  300  may provide power wirelessly to levitated item  100 . For example, magnetic fields generated by levitator  200 ,  300  may induce current in an induction coil (or other structure capable of having a current induced therein) of item  100 , which current may be used to power item  100  or elements thereof. For example, the current induced in item  100  may power a light emitting diode (LEDs), an accelerometer or other sensor, a compass, and/or a display screen of item  100 . In cases where item  100  is an electronic device (e.g., a smartphone, smartwatch, or other computing device) the current induced by levitator  200 ,  300  may power the device itself. 
     In some embodiments a levitated item  100  can be used as an input to an outside system or device  500  that may be remote from levitator  200 ,  300  (see  FIGS. 2 and 8 ). For example, item  100  may be levitated in a default position or motion (static or dynamic) in the absence of an outside force applied to item  100 , similarly as described elsewhere herein. But when an outside force is applied to move item  100  from the default position or motion, position sensors  346  sense that motion and controller  342  sends a control signal representative of the motion (or applied force) to another device or system, which interprets it as an input. For example, an item  100  may be levitated in a default position centered two inches above levitator  200 ,  300 . If a person pushes levitated item  100  in a first direction (e.g., away from the person), the signal generated by control system  340  due to this motion may be interpreted by outside system or device  500  as an input to increase a parameter (e.g., volume on an audio system, scrolling up or down on a computer program); and if the person pulls levitated item  100  in a second direction (e.g., toward the person), the signal generated by control system  340  due to this motion may be interpreted by outside system or device  500  as an input to decrease the parameter. Control system  340  and outside system or device  500  can be programmed to interpret any motion caused by a person (or other outside force) as any desired input. For example, rather than being pushed or pulled as described above to increase or decrease a parameter, item  100  may be raised or lowered; moved left or right; tilted forward, rearward, leftward, or rightward; or rotated clockwise or counterclockwise. In some embodiments, item  100  can be used as a mouse input for a computer, such that the motion of a cursor or other on-screen element is directed by motion of item  100 . In some embodiments, item  100  can be used as a joystick or other virtual control (e.g., in a video game or computer-aided-design (CAD) program) to control motion of another item  100  or a virtual item (e.g., to manipulate a three-dimensional rendering of an object in a CAD or other program). In such embodiments, the other item  100  or virtual item may mimic the motion of item  100  moved by the user. 
     In some embodiments (e.g., where item  100  is used as a control or input for an outside system or device  500 ), item  100  may provide tactile feedback to the user manipulating it. For example, resistance to motion may be increased as item  100  is moved farther from its default state (e.g., by increasing appropriate electromagnetic coils  310 ,  320 ,  330 ). Or such resistance may be a constant force opposing the change in position or rotation. In some embodiments, item  100  may pulse to provide a kind of haptic feedback as it is moved (e.g., rapid repeated increases and decreases in resistance to motion to evoke a buzzing, clicking, or vibrating feeling as item  100  is turned). 
     In some embodiments, multiple levitators  200 ,  300  are used together in a levitation system. Such a configuration may be useful, for example, in a retail setting to display different types of products or similar products having different specifications. In some embodiments certain of the displayed items  100  may be made to move by levitators  200 ,  300  in order to draw attention to them (e.g., by oscillating (e.g., up-and-down, side-to-side, or rotating back-and-forth), bouncing, twirling, being raised (e.g., above others), being lowered (e.g., below others), being turned in a direction different from others, being turned toward a location (e.g., that of a control panel or customer)). These certain items  100  may be those that meet a certain criteria. The criteria may be parameters input (e.g., into a control panel linked to control system  240 ,  340 ) by a customer (e.g., to highlight those items that match specifications for which the customer is searching). The criteria may be set by a retailer (e.g., to highlight items that are on new or on sale). 
     Electromagnetic coils described herein may be formed of coiled electrically conductive material, such as wire (e.g., copper wire or aluminum wire). The gauge, length, number and arrangement of turns, and coil direction may be varied as would be understood by one of skill in the art to produce or be capable of producing a desired magnetic field output for an intended current input. 
     Electromagnetic coils described herein may be replaced or supplemented with permanent magnets or any other structure that generates a magnetic field, and permanent magnets described herein may be replaced or supplemented with electromagnetic coils or any other structure that generates a magnetic field to achieve some or all of the functions described herein, as would be understood by one of skill in the art. 
     The above describes embodiments of the present invention with particular reference to two example levitators: levitator  200  and levitator  300 . As one of skill in the art would appreciate, described structural features, operation, and potential use cases of each of levitators  200  and  300  can be applied independently to or interchanged with features of other levitators, including the other of levitators  200  and  300 . 
     The foregoing descriptions of the specific embodiments described herein are presented for purposes of illustration and description. These exemplary embodiments are not intended to be exhaustive or to limit the embodiments to the precise forms disclosed. All specific details described are not required in order to practice the described embodiments. 
     It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings, and that by applying knowledge within the skill of the art, one may readily modify and/or adapt for various applications such specific embodiments, without undue experimentation, without departing from the general concept of the present invention. Such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. 
     The Detailed Description section is intended to be used to interpret the claims. The Summary and Abstract sections may set forth one or more but not all exemplary embodiments of the present invention as contemplated by the inventor(s), and thus, are not intended to limit the present invention and the appended claims. 
     The present invention has been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed. 
     The phraseology or terminology used herein is for the purpose of description and not limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan. 
     The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.

Metadata:
Filing Date: 20150827
Publication Date: 20180522
Grant Date: 20180522
Priority Date: 20150827
Inventors: PUSKARICH, PAUL
DELLA SILVA, CLARK D.
SCHWALBACH, CHARLES A.
KUMKA, David Samuel
WEIDNER, ANDY
MUSTAFA, PAULINA
GERY, JEAN-MARC
Assignee: APPLE INC
CPC Classifications: [{"code": "F16C32/0446", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C32/0444", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C32/0453", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02K7/09", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02K11/215", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C32/0457", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C32/0446", "inventive": true, "first": true, "tree": "[]"}, {"code": "F16C32/0453", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02K7/09", "inventive": true, "first": true, "tree": "[]"}, {"code": "F16C32/0453", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02K11/215", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C32/0457", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02N15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C32/0446", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C32/0457", "inventive": true, "first": false, "tree": "[]"}, {"code": "F16C32/0444", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02N15/00", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 58096917