Abstract:
A guitar controller for a tablet computer is disclosed. The guitar controller includes a body having a cavity formed therein sized and dimensioned to receive a tablet computer. The body has an edge on a front of the body defining an opening into the cavity. The edge has a thickness forming a lip into the opening wherein the lip is configured and arranged to be received partially over the tablet computer. A neck extends from the body and has a plurality of simulated fret positions thereon. An electronic circuit is included and configured and arranged to transmit a message encoded with presses of the simulated fret positions to the tablet computer.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent document claims priority to earlier filed U.S. Ser. No. 61/497,493, filed on Jun. 15, 2011, and U.S. Ser. No. 61/587,462, filed on Jan. 17, 2012, the entire contents of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Technical Field 
         [0003]    The present patent document relates generally to electronic music instruments and more particularly to a guitar controller for a tablet computer with a touch control interface, such as an iPad® brand tablet computer. 
         [0004]    2. Background of the Related Art 
         [0005]    Tablet computers, such as the Apple iPad brand tablet computer, have emerged as popular devices for creating and composing music. Although a tablet computer&#39;s touch screen offers some interesting possibilities for the control and creation of music, these touch screens are inherently small when compared to the control surface of a guitar or piano. Also, the touch interface requires users to learn a new way of playing and composing music. That is, the touch control interface does not permit a user to interact with a full size piano keyboard or simultaneously strum and operate the frets of a simulated guitar in the same manner as operating the respective music instrument. 
         [0006]    Therefore, there is a perceived need in the industry for an interface for a tablet computer that permits a user to compose and play music as one would with a traditional instrument. 
       SUMMARY 
       [0007]    The present invention solves the problems of the prior art by providing a controller for a tablet computer that permits a musician to create music in a way that is familiar to guitar players, yet offers new possibilities for music creation, in a cost-effective manner. In addition, the controller can teach the fundamentals of guitar chords and playing to budding musicians. 
         [0008]    The controller uses the tablet computer&#39;s touch screen and digital signal processing (“DSP”) engine to control and produce the sound. Use of the tablet computer&#39;s inherent components reduces the cost of the controller because these components do not need to be included in the controller. 
         [0009]    The controller includes a guitar-style neck so that the control of the pitch values will be familiar to guitar players. Other controls can be added such as whammy bar to bend pitch, just like in a traditional electric guitar, and knobs to control volume and audio effects like distortion. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description, appended claims, and accompanying drawings where: 
           [0011]      FIG. 1  is a sketch of a first embodiment of the controller showing a simulated guitar having neck with number of fret buttons to simulate chords and notes; 
           [0012]      FIG. 2  is a sketch of a second embodiment of the controller showing a simulated guitar having a neck with a number of touch sensitive strips simulating frets on the guitar; 
           [0013]      FIG. 3  is a sketch of a third embodiment of the controller showing a tablet computer that may be front-loaded into the guitar body; 
           [0014]      FIG. 4  is a diagram of the an embodiment of the electrical operation of the controller using low speed serial communications with the tablet computer and also showing two distinct methods of audio output; 
           [0015]      FIG. 5  is a diagram of the alternative embodiment of the electrical operation of the controller using a high-speed data port with the tablet computer and showing two distinct methods of audio output; 
           [0016]      FIG. 6  is a diagram of yet a third alternative embodiment of the electrical operation of the controller using wireless communication with the tablet computer; 
           [0017]      FIG. 7  is a front perspective view of a fourth embodiment of the controller; 
           [0018]      FIG. 8  is a top perspective view of a fourth embodiment of the controller; 
           [0019]      FIG. 9  is a rear perspective view of the body of the controller showing the door mechanism; 
           [0020]      FIG. 10  is a front perspective view of the body of the controller showing the depth of the tablet computer in the body; 
           [0021]      FIG. 11  is a front perspective view of a fifth embodiment of the controller; 
           [0022]      FIG. 12  is a front perspective view of the fifth embodiment with the tablet computer removed from the body of the controller; 
           [0023]      FIG. 13  is a rear perspective view of the fifth embodiment of the controller; 
           [0024]      FIG. 14  is a cross-section view through line  14 - 14  of  FIG. 11 ; 
           [0025]      FIG. 15  is a cross-section view through line  15 - 15  of  FIG. 13 ; 
           [0026]      FIG. 16  is a front perspective view of an insert for adapting a handheld computing device for use in the controller; and 
           [0027]      FIG. 17  is a rear perspective view of an insert for adapting a handheld computing device for use in the controller. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0028]    Referring now to  FIG. 1 , a first embodiment of the controller is generally shown at  10 . The controller  10  includes a simulated guitar body  12 , in which there is a cavity  14  to capture and hold a tablet computer  16 , such as an Apple iPad brand tablet computer, while the controller  10  is being played. A connector or cable is included that connects to the tablet computer  16 . In the case of an iPad brand tablet computer, the iPad&#39;s 30-pin bottom connector is used. Extending from the guitar body  12  is a guitar neck  18  with a number of note buttons  20  located at simulated fret positions. A head  22  may extend from the guitar neck  18 . 
         [0029]    The note buttons  20  may include lights, such as LEDs, which may be lit individually and in sequence. When lit sequentially, the user can be taught how to play the guitar or how to play a particular song. The lights within the note buttons  20  may also light when the note buttons  20  are pressed by the user in a playing mode. 
         [0030]    The body  12  has an edge  28  on a front  32  of the body  12  defining an opening into the cavity  14 . The edge  28  forms a lip  30  into the opening wherein the lip  30  is received partially over the tablet computer  16 . 
         [0031]    In addition, there can be an audio output  24  on the guitar body  12 . Preferably, this audio output is in the form of a ¼″ mono or stereo female connector. The audio output  24  is connected to the tablet computer  16  audio output. In the case of an iPad brand tablet computer, the audio output is on the iPad&#39;s 30-pin connector. 
         [0032]    The guitar body  12  may include one or more knobs  26  to control volume, tone, or other audio effects. 
         [0033]    Referring now to  FIG. 2 , a second embodiment of the controller is shown generally at  100 . In addition to the features described above for the first embodiment  10 , the second embodiment  100  includes a guitar neck  102  extending from the guitar body  112 . The guitar neck  102  includes a plurality of touch strip controllers  104  that simulate frets and finger position on the neck  102  of the guitar body  112  instead of using note buttons  20 . The guitar neck  102  may include a head  122  opposite the body  112 . The guitar body  112  may also, likewise, include an audio output  124  and one or more knobs  126  to control volume, tone, or other audio effects. The body  112  includes a cavity  114  sized and dimensioned to receive a tablet computer  16  therein. 
         [0034]    The touch strip controllers  104  may include lights, such as LEDs, which may be lit individually and in sequence. When lit sequentially, the user can be taught how to play the guitar or how to play a particular song. The lights within the touch strip controllers  104  may also light when the touch strip controllers  104  are pressed by the user in a playing mode. 
         [0035]    The body  112  has an edge  128  on a front  132  of the body  112  defining an opening into the cavity  114 . The edge  128  forms a lip  130  into the opening wherein the lip  130  is received partially over the tablet computer  16 . 
         [0036]    As can be seen in  FIG. 3 , a third embodiment  200  shows that the opening on the cavity (occupied by the tablet computer  16 ) of the guitar body  212  may be oriented in another direction to receive the tablet computer  16 . Although the cavity  214  shown in  FIGS. 1 and 2  shows a rear-loading cavity, and  FIG. 3  shows a front-loading cavity, one skilled in the art would appreciate that the cavity may be configured to receive the tablet computer  16  in some other direction as may be directed by the shape of the guitar body  212  and desired features of the controller  10 , 100 ,  200 . The body  212  has an edge  202  on a front  204  of the body  212  defining an opening into the cavity. The edge  202  forms a lip  206  into the opening wherein the lip  206  is received partially over the tablet computer  16 . 
         [0037]    The guitar body  212  may also, likewise, include an audio output  224  and one or more knobs  226  to control volume, tone, or other audio effects. The guitar body may also include a neck  228 , which may include a head  222  opposite the body  212  like the other embodiments  10 ,  100 . The neck  226  includes a plurality of simulated fret positions  230 , which may be note buttons or touch strip controllers, like the other embodiments  10 ,  100 . 
         [0038]    Three embodiments of implementing the electronic circuit for the various embodiments of the controller are shown generally in  FIGS. 4-6 . In the first method  300 , shown in  FIG. 4 , a microprocessor  302  authenticates the tablet computer  16 , such as the iPad brand tablet computer, through dedicated low-speed serial communication pins on the iPad&#39;s 30-pin connector via an authentication chip  305 . The second method  400 , shown in  FIG. 5 , to implement the electrical operation of the controller is to communicate with the tablet computer  16  solely through a high-speed data controller  404 , such as a universal serial bus controller. In a third method  500 , shown in  FIG. 6 , the electrical operation of the controller uses wireless communication with the tablet computer  16 . 
         [0039]    Turning first to  FIG. 4 , a high-speed data serial controller  304 , such as a universal serial bus controller, reads the state of the various guitar controls  306 , i.e. finger position on the buttons and/or touch sensitive frets controls, whammy bar, and knobs. The state of the controls is read by the controller  304  and converted into messages (such as Core MIDI messages) sent to the tablet computer  16  to trigger actions such as determining pitch of the note being played, applying audio effects like distortion, or bending pitch. Software running on the tablet computer  16  receives the messages and plays a sound out the audio output of the tablet computer  16  in response to the messages received. Audio output of the tablet computer  16  may be transmitted digitally via the high-speed data controller  304  or out a standard analog line output equipped on most tablet computers  16 . 
         [0040]    In addition, the controller  304  may receive messages from the software running on the tablet computer  16  to active and deactivate selected lights in the simulated fret positions of the touch strip controllers or note buttons. 
         [0041]    In this embodiment, there are two methods for outputting audio from the tablet computer  16 . The first  308  is through the analog line output  309  included on the tablet computer  16  itself, marked as “Method  1 ” in  FIG. 4 . The analog line output  309  is passed through a differential operational amplifier  310 , which may include an optional volume control. The differential operational amplifier  308  is connected to one or more connectors  312 , such as XLR jacks, ¼″ jack, ⅛″ jack, RCA jacks, or other audio connectors. 
         [0042]    The second method  314  for outputting audio from the tablet computer  16 , marked “Method  2 ” is digitally through the high-speed data controller  304 . Digital audio transmitted via the high-speed data controller  304  is passed through a digital-to-analog converter  316 . The digital-to-analog converter  316  is connected to one or more connectors  318 , such as XLR jacks, ¼″ jack, ⅛″ jack, RCA jacks, or other audio connectors. The analog output of the digital-to-analog converter  316  may also be passed through a differential operational amplifier  320 , which may include an optional volume control, prior to being passed transmitted to the connectors  318 . Although both methods  308 ,  314  are shown in  FIG. 4 , in practice only one would be used. 
         [0043]    Turning now to  FIG. 5 , a second method  400  to implement the controller is to communicate with the tablet computer  16  solely through the high-speed data controller  404  that is integrated with a microprocessor. A microprocessor with high-speed data controller  404  communicates with and authenticates the tablet computer  16  to enable features through an authentication chip  405 , if needed. The microprocessor also reads the state of the guitar controls  406  and converts them to messages (such as Core MIDI format) that are transmitted to the tablet computer  16  to trigger actions such as determining pitch of the note being played, applying audio effects like distortion, or bending pitch. Software running on the tablet computer  16  receives the messages and plays a sound out the audio output of the tablet computer  16  in response to the messages received. Audio output of the tablet computer  16  may be transmitted digitally via the high-speed data controller  404  or out a standard analog line output  409  equipped on most tablet computers  16 . 
         [0044]    In addition, the integrated microprocessor and high-speed data controller  404  may receive messages from the tablet computer  16  to activate and deactivate selected lights in the simulated fret positions of the touch strip controllers or note buttons. 
         [0045]    In this embodiment  400 , there are two methods for outputting audio from the tablet computer  16 . The first  408  is through the analog outputs  409  included on the tablet computer  26 , marked as “Method  1 ” in  FIG. 5 . The analog line output  409  is passed through a differential operational amplifier  410 , which may include an optional volume control. The differential operational amplifier  410  is connected to one or more connectors  412 , such as XLR jacks, ¼″ jack, ⅛″ jack, RCA jacks, or other audio connectors. 
         [0046]    The second method  414  for outputting audio from the tablet computer  16 , marked “Method  2 ” is digitally through the high-speed data controller  404 . Digital audio transmitted via the high-speed data controller  404  is passed through a digital-to-analog converter  416 . The digital-to-analog converter  416  is connected to one or more connectors  418 , such as XLR jacks, ¼″ jack, ⅛″ jack, RCA jacks, or other audio connectors. The analog output of the digital-to-analog converter  416  may also be passed through a differential operational amplifier  420 , which may include an optional volume control, prior to being passed transmitted to the connectors  418 . 
         [0047]    Although both methods  408 ,  414  are shown in  FIG. 5 , in practice only one would be used. 
         [0048]    Turning now to  FIG. 6 , a third method  500  to implement the electrical operation of the controller  10 ,  100  is to use a wireless communication protocol, such as a Bluetooth connection. In this embodiment, the guitar controls  502  are mapped to standard Bluetooth HID commands such as QWERTY keyboard commands. The tablet computer  16  receives the commands and, using a customized software application, would interpret these commands as control signals for the controller instead of letters on a keyboard. For example, the letter “A” could be sent when the first fret is depressed and so on. 
         [0049]    One way to accomplish this would be to use a standard Bluetooth HID module such  504  as the Blue Packet BP20422 Bluetooth HID module. Other modules may be used and other wireless protocols may be used as well. 
         [0050]    Audio may also be received from the tablet computer  16  via a wireless audio module  506  implementing a wireless communication protocol, such as Bluetooth connection. The wireless audio module  506  receives the audio from the tablet computer  16  and transmits digital audio to a digital-to-analog converter  508 . The digital-to-analog converter  508  is connected to one or more connectors  510 , such as XLR jacks, ¼″ jack, ⅛″ jack, RCA jacks, or other audio connectors. The analog output of the digital-to-analog converter  508  may also be passed through a differential operational amplifier  512 , which may include an optional volume control, prior to being passed transmitted to the connectors  510 . 
         [0051]    Referring now to  FIGS. 7 and 8 , a fourth embodiment of the controller is shown generally at  600 . The controller  600  includes a simulated guitar body  612 , in which there is a cavity to capture and hold a tablet computer  16 , such as an Apple iPad brand tablet computer, while the controller  600  is being played. The body  612  has an edge  602  on a front  604  of the body  612  defining an opening into the cavity. The edge  602  has a thickness forming a lip  606  into the opening wherein the lip  606  is received partially over the tablet computer  16 . 
         [0052]    The tablet computer  16  may interface with the controller  600  with a connector or cable or wirelessly as described above with the other embodiments  200 ,  300 ,  400 . Extending from the guitar body  612  is a guitar neck  614  with a number of note buttons  616  located at simulated fret positions. (As shown in  FIGS. 9 and 10  the neck  614  may detach from the body  612 ). The electronic circuit for communicating note button  616  presses may be located in the guitar neck  616 . A head  622  may extend from the guitar neck  614 . 
         [0053]    The note buttons  616  include lights, such as LEDs, which may be lit individually and in sequence. When lit sequentially, the user can be taught how to play the guitar or how to play a particular song. The lights within the note buttons  616  may also light when the note buttons  616  are pressed by the user in a playing mode. 
         [0054]    In addition, there can be an audio output  618  on the guitar body  612 . Preferably, this audio output  618  is in the form of a ¼″ mono or stereo female connector. The audio output  618  is connected to the tablet computer  16  audio output. In the case of an iPad brand tablet computer, the audio output is on the iPad&#39;s 30-pin connector. Optionally, the audio output may be routed to a built-in speaker  620 , which may include its own volume control. 
         [0055]    The guitar body  612  may include one or more knobs  624  to control volume, tone, or other audio effects. 
         [0056]    Referring to  FIG. 9 , the tablet computer  16  is secured within the guitar body  612  by a door  626 . The door  626  is hinged by one or more hinges  628  to the rear  630  of the guitar body  612 . Although three hinges  628  are depicted, fewer or more hinges  628  may be added as is known in the art. A locking mechanism  630  secures the door  626  shut against the body  612 . Batteries powering the electrical circuit  200 ,  300 ,  400  may be housed in a battery compartment  632  contained in the door  626 . 
         [0057]    Recesses  634   a ,  634   b  are provided on the rear  630  of the guitar body  612  to allow access to the headphone output and to manipulate buttons on the tablet computer  16 , respectively, such as power, rotation lock, volume and mute switches. 
         [0058]    Referring to  FIG. 10 , the tablet computer  16  is recessed inside the body  612  of the controller  600 , thereby providing the musician tactile feedback when they have strayed off of the touch screen of the tablet computer  16 . As shown, the tablet computer  16  is recessed 4.5 mm within the guitar body, but other depths may be used. Tablet computers  16  that are mounted within a guitar body  612  in a generally flush manner suffer the limitation that the musician may lose track of where they are on the tablet computer  16  touch screen. 
         [0059]    Referring now to  FIGS. 11 and 12 , a fifth embodiment of the controller is shown generally at  700 . The controller  700  includes a simulated guitar body  712 , in which there is a cavity  708  to capture and hold a tablet computer  16 , such as an Apple iPad brand tablet computer, while the controller  700  is being played. The body  712  has an edge  702  on a front  704  of the body  712  defining an opening into the cavity  708 . The edge  702  has a thickness forming a lip  704  into the opening wherein the lip  704  is received partially over the tablet computer  16 . 
         [0060]    The tablet computer  16  may interface with the controller  700  with a connector  716  or cable or wirelessly as described above with the other embodiments  200 ,  300 ,  400 . Although not shown here, the controller  700  may have, extending from the guitar body  712 , a guitar neck with a number of note buttons or touch strip controllers located at simulated fret positions like the other embodiments shown  10 ,  100 ,  200 ,  600 . A head may extend from the guitar neck as well. The electronic circuit  300 ,  400 ,  500  for communicating note button or touch strip controller presses may be located in the guitar neck in order to reduce manufacturing cost. 
         [0061]    In addition, there can be an audio output  714  on the guitar body  712 . Preferably, this audio output  714  is in the form of a ¼″ mono or stereo female connector. The audio output  714  is connected to the tablet computer  16  audio output. In the case of an iPad brand tablet computer, the audio output is on the iPad&#39;s 30-pin connector. Optionally, the audio output may be routed to a built-in speaker  720 , which may include its own volume control. 
         [0062]    The guitar body  712  may include one or more knobs  718  to control volume, tone, or other audio effects. 
         [0063]    Referring to  FIG. 13 , the tablet computer  16  is secured within the guitar body  712  by a door  726 . The door  726  is hinged by one or more hinges  728  to the rear  730  of the guitar body  712 . Although three hinges  728  are depicted, fewer or more hinges  728  may be added as is known in the art. A locking mechanism  730  secures the door  726  shut against the body  712 . Batteries powering the electrical circuit  300 ,  400 ,  500  may be housed in a battery compartment  732  contained in the door  726 . 
         [0064]    A recess  734  is provided on the rear  730  of the guitar body  712  to allow access to the headphone output and to manipulate buttons on the tablet computer  16 , such as power, rotation lock, volume and mute switches. 
         [0065]    Referring to  FIG. 14-15 , the tablet computer  16  is recessed inside the body  712  of the guitar within the cavity  714 , the lip  706  providing the musician tactile feedback when they have strayed off of the touch screen of the tablet computer  16 . As shown, the tablet computer  16  is recessed 4.5 mm within the guitar body  712 , but other depths may be used. Tablet computers  16  that are mounted within a guitar body  712  in a generally flush manner suffer the limitation that the musician may lose track of where they are on the tablet computer  16  touch screen. 
         [0066]    The locking mechanism  730  includes a pair of locking members  736  biased outwardly from each other via a spring  738 . The locking members  736  include finger holds  740 , which a user squeezes together to release the locking mechanism  730  permitting the door  726  to be opened. Each locking member  736  includes a beveled tongue  742  that engages reliefs in the guitar body  712  to lock the door  726  shut. 
         [0067]    The interior side  744  of the door  726  includes a compressable layer  746  that deforms to capture the tablet computer  16  against the lip  706  of the guitar body  712 . 
         [0068]    Referring now to  FIGS. 16-17 , an insert  800  is shown for adapting a smaller form factor of a tablet computer or a smaller smartphone or handheld computing device  802 , such as an iPhone or iPod Touch brand handheld computing devices, into the controller  10 ,  100 ,  600 ,  700 . The insert  800  is shaped like a tablet computer  16  and is sized and dimensioned to fit within the cavity  14 ,  114 ,  214 ,  714  of the body  12 ,  112 ,  212 ,  512 ,  612 ,  712  of the controller  10 ,  100 ,  200 ,  600 ,  700 . 
         [0069]    An adapter plate  808  is fitted to the top surface  804  of the insert  800 . The adapter plate  808  includes a surface defining an aperture  806  through the adapter plate  808 , which reveals the handheld computing device  802  when captured in the insert  800 . Different adapter plates  808  may be used depending on the handheld computing device  802  that is desired to be used with the controller. Specifically, the shape and size of the aperture  806  is changed to accommodate different handheld computing devices  802 . 
         [0070]    A strap  810  hinged  812  to the bottom of the insert  800  at one end. The opposite end of the strap  810  engages a mating formation  814  on the insert  800  to secure the handheld computing device  802  within the insert  800 . 
         [0071]    In the most general sense, touching the touch surface of the tablet computer  16  triggers the sound while operating the controls  20 ,  104 ,  230 ,  306 ,  406 ,  502 ,  616  on the guitar neck  18 ,  102 ,  228 ,  614  determines the pitch of the sound or sounds, either by controlling individual notes or by determining whole chords with one press on the simulated fret positions. Either the tablet computer  16  or the controls  20 ,  104 ,  230 ,  306 ,  406 ,  502 ,  616  on the guitar neck  18 ,  102 ,  228 ,  614  may, in addition, affect the timbre of the sound, modulate the sound, or affect the sound in another way as is known in the art. Traditionally, a “whammy bar” is on the body of the guitar and would be used to bend the pitch of the sound. A whammy bar may be included on the controller  10 ,  100 ,  200 ,  300 ,  400 ,  500 ,  600 ,  700  to provide similar pitch-bending function as is known in the art. 
         [0072]    It would be appreciated by those skilled in the art that various changes and modifications can be made to the illustrated embodiments without departing from the spirit of the present invention. All such modifications and changes are intended to be within the scope of the present invention.