Abstract:
A tactile metronome for use by a musician generally includes a signal generator for producing an electrical signal according to a desired timing scheme and a tactile transducer in electrical communication with the signal generator. The tactile transducer, which may take the form of a piezoelectric device, a buzzer, electrodes or any substantial equivalent, is adapted to impart a tactile sensation to the musician in response to the generated electrical signal. A strap, which may be formed from an elastic material or a soft cloth material with hook and loop fasteners, is provided to secure the tactile transducer in place on the musician&#39;s body.

Description:
RELATED APPLICATIONS 
   This application claims priority, under 35 U.S.C. § 120 as a continuation-in-part, to P.C.T. international application Serial No. PCT/US03/23633 filed Jul. 29, 2003 and designating the United States, which is a continuation of U.S. patent application Ser. No. 10/306,263 filed Nov. 27, 2002 now abandoned. By this reference the full disclosures, including the drawings, of P.C.T international application Serial No. PCT/US03/23633 and U.S. patent application Ser. No. 10/306,263 are incorporated herein as though now set forth in their respective entireties. Additionally, the full disclosure, including the drawings, of Applicant&#39;s co-pending U.S. patent application entitled VIBRATING TRANSDUCER WITH PROVISION FOR EASILY DIFFERNTIATED MULTIPLE TACTILE STIMULATIONS filed May 26, 2005 in the name of David M. Tumey is incorporated herein as though now set forth in its entirety. 

   FIELD OF THE INVENTION 
   The present invention relates to music technology. More particularly, the invention relates to a metronome with provision for communication with a musician through tactile stimulation and being particularly adapted for the generation and communication of complex rhythmic patterns and measure timing, e.g., the timing of downbeats, in addition to being adapted to the communication of variable tempos. 
   BACKGROUND OF THE INVENTION 
   The metronome is well established as a fundamental tool of musical education. Having been developed before the advent of the electrical apparatus, the traditional metronome comprises a mechanical assembly adapted to generate a clicking sound at a desired beat frequency. With the advent of modern electronics a very precise audio output may now be produced or, as is particularly useful for the musical education of deaf persons, the output signal from the metronome may be communicated with a visual indicator such as a flashing light. 
   While the improvements made possible through technology are meritorious, Applicant has discovered that the improvements generally serve only to better implement a fundamentally flawed method. In particular, Applicant has noted that the audio nature of the metronome, which is apparently a holdover from the days of primitive technology, is distracting to the musician and, in at least some musical environments, ineffective due to the inability of the musician to clearly hear the audio signal. Additionally, the audio signal is wholly inappropriate for use by the hearing impaired. While this latter issue has been at least addressed through metronomes with visual outputs, it is noted that the use of the visual indicator mandates that the musician completely memorizes his or her music. 
   It is therefore an overriding object of the present invention to improve over the prior art by providing a metronome that is free of the foregoing flaws. In particular, it is an object of the present invention to provide a metronome having a tactile output such that the musician may feel the desired beat regardless of the volume of the performance or a particular user&#39;s physical limitations. Additionally, it is an object of the present invention to provide such a metronome that also may be programmed to provide enhanced capabilities such as, for example, complex output rhythms and/or tactile stimulation designed for the development of articulation. Finally, it is an object of the present invention to provide such a metronome that is also economical to produce and easy to use. 
   SUMMARY OF THE INVENTION 
   In accordance with the foregoing objects, the present invention—a tactile metronome for use by a musician—generally comprises a signal generator for producing an electrical signal according to a desired timing scheme and a tactile transducer in electrical communication with the signal generator. The tactile transducer, which may comprise a piezoelectric device, a buzzer, electrodes, a bone density resonator, an electrical stimulation device, a mechanical transducer, an eccentric motion generator or any substantial equivalent, is adapted to impart a tactile sensation to the musician in response to the generated electrical signal. A strap, which may comprise an elastic material or a soft cloth material with hook and loop fasteners, is preferably provided to secure the tactile transducer in place on the musician&#39;s body. 
   In at least one embodiment, the signal generator is adapted to produce complex rhythms and may be programmable such that the musician may define the complex rhythm. In this embodiment, the signal generator preferably further comprises a micro-controller. 
   In at least one embodiment of the present invention, a vibrating transducer for producing multiple, readily differentiable tactile stimulations is provided. In the preferred embodiment of the present invention, the vibrating transducer generally comprises a rigid housing; an electric motor enclosed within the rigid housing and having attached thereto an eccentric weight; and wherein the electric motor is supported within the rigid housing by a flexible motor mount. The rigid housing comprises a generally cylindrically shaped tube. 
   The flexible motor mount may be formed of a cushion, which may be made from foam material or the like. In at least one embodiment of the present invention, the cushion is wrapped substantially about the electric motor, centering the electric motor within the cylindrically shaped tube forming the rigid housing. In order to facilitate manufacture of the vibrating transducer of the present invention, the cushion may be wrapped by a securing sheet such as, for example, a thin paper wrapping, a length of adhesive tape or the like. 
   In a further embodiment of the vibrating transducer of the present invention, a driver circuit may be provided for facilitating operation of the electric motor. The driver circuit may include a current amplifier. 
   A display, such as a liquid crystal display or a light emitting diode display, is provided to facilitate selection of the desired output frequency or rhythmic pattern. Likewise, a user interface is provided for input of rhythmic patterns, operational control and the like. 
   Finally, many other features, objects and advantages of the present invention will be apparent to those of ordinary skill in the relevant arts, especially in light of the foregoing discussions and the following drawings, exemplary detailed description and appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Although the scope of the present invention is much broader than any particular embodiment, a detailed description of the preferred embodiment follows together with illustrative figures, wherein like reference numerals refer to like components, and wherein: 
       FIG. 1  shows, in a perspective view, one embodiment of the tactile metronome of the present invention as operably employed by a musician; 
       FIG. 2  shows, in a functional block diagram, the preferred embodiment of the tactile metronome of the present invention; 
       FIG. 3  shows, in an exploded perspective view, the preferred embodiment of a vibrating transducer as has been found to be optimum for use with the tactile metronome of  FIG. 2 ; 
       FIG. 4  shows, in a cross sectional side view, details of the arrangement of the internal components of the vibrating transducer of  FIG. 3 ; 
       FIG. 5  shows, in a cross sectional end view taken through cut line  5 - 5  of  FIG. 4 , additional details of the arrangement of the internal components of the vibrating transducer of  FIG. 3 ; 
       FIG. 6  shows, in a partially cut away perspective view, a representation of the forces produced in the operation of the vibrating transducer of  FIG. 3 ; 
       FIGS. 7A through 7F  show, in schematic representations generally corresponding to the view of  FIG. 5 , changes in the relative positions of various internal components of the vibrating transducer of  FIG. 3 , which changes occur as a result of the operational forces represented in  FIG. 6 ; 
       FIG. 8  shows, in a schematic diagram, details of one embodiment of a driver circuit, as depicted in  FIG. 2 , appropriate for operation of the vibrating transducer of  FIG. 3 ; 
       FIG. 9  shows, in a voltage waveform aligned with a musical score, a representative signal as may be generated by the signal generator of  FIG. 2  for operation through the driver circuit of  FIG. 2  of the vibrating transducer of  FIG. 3 , the waveform having characteristics such that the tempo and timing of measures of the score of  FIG. 9  may be readily perceived by a musician employing the tactile metronome of the present invention in a manner such as depicted in  FIG. 1 ; and 
       FIG. 10  shows, in a voltage waveform aligned with a musical score, a representative signal as may be generated by the signal generator of  FIG. 2  for operation through the driver circuit of  FIG. 2  of the vibrating transducer of  FIG. 3 , the waveform having characteristics such that the tempo and timing of measures, as well as the rhythm, of the score of  FIG. 10  may be readily perceived by a musician employing the tactile metronome of the present invention in a manner such as depicted in  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Although those of ordinary skill in the art will readily recognize many alternative embodiments, especially in light of the illustrations provided herein, this detailed description is exemplary of the preferred embodiment of the present invention, the scope of which is limited only by the claims appended hereto. 
   Referring now to the  FIGS. 1 and 2 , the tactile metronome  20  of the present invention is shown to generally comprise a signal source  41  in electrical communication with a contact device  21  comprising, at minimum, a tactile transducer  23  and which, as will be better understood further herein, is adapted to impart to a user  48  a tactile stimulation. As particularly shown in  FIG. 2 , the signal source  41  preferably comprises a signal generator  42 , for generating an electrical signal for delivery to the tactile transducer  23 , the generated electrical signal having electrical characteristics indicative of user selected measure (or downbeat) timing, tempo and rhythmic pattern, and a controller  47  for facilitating user selection of the characteristics of the signal generated by the signal generator  42 . A display, which may comprise a liquid crystal display, light emitting diode display or any other substantially equivalent structure, and a user input system, which may comprise a touch screen control, computer interface such as a USB port, wireless interface or the like, or buttons or dials, are also preferably provided in connection with the controller  47  for use inputting and monitoring user selections. 
   As particularly shown in  FIG. 1 , the contact device  21 , which is preferably adapted for wear on the user&#39;s ankle, wrist, chest, spinal region or other appropriate location, generally comprises a strap  22  of soft cloth and/or elastic material having a tactile transducer  23  affixed to an interior side thereof. The strap  22  may comprise releasably engageable hook and loop type fasteners, such as are commercially available under the well-known trademark “VELCRO,” or any other substantially equivalent fastener system, for snuggly securing the strap  22  about the user&#39;s ankle, wrist, chest, spinal region or other location. In this manner, those of ordinary skill in the art will appreciate that the strap  22  is adapted to facilitate intimate contact between the tactile transducer  23 , which may comprise a piezoelectric device, buzzer, pair of electrodes, a bone density resonator, an electrical stimulation device, a mechanical transducer, an eccentric motion generator or any other substantially equivalent structure capable of imparting the desired tactile stimulation, and the user&#39;s body. Additionally, an electrical cable or power cord  30 , which preferably terminates in a standard plug  31 , enabling the signal source  41  of the present invention to be utilized with any of a variety of tactile transducers  23 , provides electrical communication between the contact device  21  and an output jack from the signal source  41 . 
   In use, as particularly shown in  FIG. 1 , a musician  48  affixes the tactile transducer  23  in a minimally obtrusive location utilizing the strap  22 . The musician  48  then connects the electrical cable  30  between the contact device  21  and the signal source  41  by inserting the standard plug  31  into the output jack of the signal source  41 . An output power level selector  45  is preferably provided, as described in more detail further herein, to adjust the “feel” of the tactile metronome  20  of the present invention. 
   With the tactile transducer  23  positioned as desired, the musician  48  utilizes the provided control input and display to set the beats per minute and, if desired, rhythmic pattern, to be generated by the signal generator  42 . To this end, those of ordinary skill in the art will recognize that the display should be adapted to provide a digital readout of the current setting. Additionally, however, it is contemplated by the present invention that the display may also be adapted to provide a graphical readout comprising a musical score, such as those shown in the upper portions of  FIGS. 9 and 10 , especially when the controller  47  is programmed to produce more complicated rhythms such as that depicted in  FIG. 10 . In any case, with the tactile metronome  20  of the present invention in proper position and set up as desired, the musician  48  may perform his or her musical instrument of choice while literally feeling the desired beat and without having to divert attention to listen to a traditional metronome or watch for flashing lights or the like. 
   As will be appreciated by those of ordinary skill in the art, especially in light of this exemplary description, the controller  47  may be readily provided with a timing circuit or programmed to provide complex beat patterns. In such an embodiment, a communication interface or other programming input as well as read only or non-volatile random access memory are preferably provided for the signal source  41  such that the musician  48  may input and/or select a desired beat pattern. In one such embodiment, as will be discussed in further detail herein, an electronic score may be programmed into the controller, either directly or through a computer or PDA interface, whereafter the user need only select desired tempo and starting point to have the tactile metronome  20  of the present invention produce rhythmic stimulation for literally a complete musical selection. 
   Referring now to the  FIGS. 3 through 7  in particular, a preferred embodiment of the tactile transducer  23  is shown to comprise a vibrating transducer  24  having the unique ability to produce multiple easily differentiated tactile stimulations. As shown in the figures, such a vibrating transducer  24  generally comprises an electric motor  28  having attached thereto an eccentric weight  33  and encased within a rigid housing  25 . As is typical with pager transducers and the like, operation of the electric motor  28  turns a shaft  34  upon which the eccentric weight  33  is mounted with, for example, a pin  35 . As will be appreciated by those of ordinary skill in the art, rotation upon the shaft  34  of the eccentric weight  33  produces a vibratory effect upon the motor  28  resulting from the forward portion  32  of the motor  28  attempting to shift laterally outward from the nominal axis  36  of rotation of the shaft  34 , as depicted by the centrifugal force lines F in  FIG. 6 . 
   In typical implementations of this principle, the electric motor is rigidly fixed to some body such as, for example, a pager or cellular telephone housing with mounting clamps, brackets or the like. In the present implementation, however, unlike the vibrating transducers of the prior art, the electric motor  28  is encased within a rigid housing  25  by the provision of a flexible motor mount  37 , which allows the forward portion  32  of the electric motor  28  to generally wobble within the rigid housing  25  as the eccentric weight  33  is rotated upon the motor shaft  34 . In this manner, the resultant forces F are the product of much greater momentum in the eccentric weight  33  than that obtained in the fixed configuration of the prior art. 
   In the preferred implementation, as particularly detailed in  FIGS. 3 through 6 , the flexible motor mount  37  generally comprises a wrapping of preferably foam cushion material  38 , which is sized and shaped to snuggly fill the space provided between the electric motor  28  and the interior of the rigid housing  25 . To facilitate manufacture of the vibrating transducer  24 , as generally depicted in  FIG. 3 , the foam cushion  38  may be held in place about the body of the electric motor  28  with a cushion securing sheet  40 , which may comprise a thin paper glued in place about the cushion  38 , thin adhesive tape or any substantially equivalent means. To complete the manufacture of the vibrating transducer  24 , the cushioned electric motor  28 , with eccentric weight  33  attached to its shaft  34 , is inserted into the rigid housing  25  and secured in place by the application of epoxy  27  into the open, rear portion  26  of the housing  25 . As will be understood by those of ordinary skill in the art, the epoxy  27  also serves to stabilize the power cord  30  to the electric motor  28 , thereby preventing accidental disengagement of the power cord  30  from the electric motor  28 . 
   Referring now to  FIGS. 5 through 7  in particular, the enhanced operation of the vibrating transducer  24  is detailed. At the outset, however, it is noted that in order to obtain maximum vibratory effect, the rigid housing  25  is provided in a generally cylindrical shape, as will be better understood further herein. In any case, as shown in the cross sectional view of  FIG. 5 , and corresponding views of  FIGS. 7A through 7F , the forward portion  32  of the electric motor  28  is encompassed by the forward portion  39  of the foam cushion  38 . At rest, i.e. without the electric motor  28  in operation, the electric motor  28  is substantially uniformly surrounded by the foam cushion  38 , as shown in  FIG. 7A . 
   Upon actuation of the electric motor  28 , however, the centrifugal forces F generated by the outward throw of the eccentric weight  33  causes the axis of rotation  36  of the motor&#39;s shaft  34  to follow a conical pattern, as depicted in  FIG. 6 . As a result, the forward portion  32  of the electric motor  28  is thrown into the forward portion  39  of the foam cushion  38 , depressing the area of cushion adjacent the eccentric weight  33  and allowing expansion of the portion of the cushion generally opposite, as depicted in  FIGS. 7B through 7F  corresponding to various rotational positions of the eccentric weight  33 . 
   As is evident through reference to  FIGS. 7B through 7F , the cooperative arrangement of the cushion  38  about the electric motor  28 , as also enhanced by the cylindrical shape of the rigid housing  25 , allows the eccentric weight  33  to build greater momentum than possible in embodiments where the motor is rigidly affixed to a body. As the forward portion  39  of the foam cushion  38  compresses under the centrifugal forces F of the eccentric weight  33 , however, a point is reached where the foam cushion  38  is no longer compressible against the interior wall of the rigid housing  25  and the forward portion  32  of the electric motor  28  is repelled away from the interior wall toward the opposite portion of interior wall. 
   The result is a vibratory effect much more pronounced than that obtained in prior art configurations calling for the rigid affixation of an electric motor to a housing. Additionally, Applicant has found that the resulting pronounced vibratory effect is generally more perceptible to the human sense of touch than is that produced by prior art configurations. In particular, small differences on the order of tens of milliseconds or less in duration of operation of the vibrating transducer  20 , i.e. duration of powering of the electric motor  28 , are easily perceived and differentiated. As a result, this implementation of the vibrating transducer  24  is particularly adapted for implementation of the tactile metronome  20  of the present invention, which preferably comprises provision for distinct tactile stimuli representing downbeats versus divisional beats as well as the generation and communication of complex rhythms, which may require very quickly perceived stimulations with very little pause therebetween. 
   As previously discussed, the signal source  41  of the tactile metronome  20  of present invention preferably comprises a driver circuit  43  for interfacing with the tactile transducer  23 . In particular, as shown in  FIG. 8 , such a driver circuit  43  preferably comprises an output amplifier  44 , which will generally be required for any implementation in which logical level signals will be expected to drive an electric motor such as is utilized in the preferred implementation of vibrating transducer  24 . As will be appreciated by those of ordinary skill in the art, this requirement stems from the fact that such an electric motor  28  will generally have a current requirement beyond the capabilities of most solid state components. Additionally, in such implementations, the driver circuit  43  will also require implementation of a power conditioning circuit  46 , as also shown in  FIG. 8 , having the capability to prevent and/or suppress voltage spiking, such as may be expected in response to the highly inductive load typical of the type of electric motor  28  utilized in the implementation of the vibrating transducer  24 . 
   As shown in  FIG. 8 , an exemplary output amplifier  44 , as is appropriate for use with the foregoing described vibrating transducer  24 , comprises a 2N3904 NPN BJT transistor Q 1 , configured as an emitter follower, coupled with a TIP 42  high current PNP transistor Q 2  in a TO- 220  heat dissipating package, for providing the necessary current for operation of the electric motor  28  of the vibrating transducer  24 . As will be recognized by those of ordinary skill in the art, the output amplifier  44  as shown may be considered a two stage, high current emitter follower. The power conditioning circuit  46 , which is preferably provided to prevent and/or suppress voltage spiking, such as may be expected in response to the highly inductive load typical of the type of electric motor  28  utilized in the implementation of the vibrating transducer  24  may be implemented by tying a 10 μF electrolytic capacitor C 1  ground from the 9-V power bus from, for example, a 9-V battery BAT. As will be recognized by those of ordinary skill in the art, the electrolytic capacitor C 1  will temporarily supply additional current to the 9-V bus as may be required to compensate for transients resulting from the draw upon the output amplifier  44  caused during startup of the electric motor  28  of the vibrating transducer  24 . Additionally, the power conditioning circuit  46  preferably comprises an ON-OFF switch SW 1  and may also include a power on indicator, if desired. 
   In order to adjust the “feel” of the tactile metronome  20  of the present invention, as previously discussed, the output from the output amplifier  44  is preferably fed through an output power level selector  45  to an output jack J 2 , into which the power cord plug  31  of the power cord  30  to the electric motor  28  of the vibrating transducer  24  may be operably inserted. As shown in  FIG. 8 , the output power level selector  45  preferably comprises a 22 Ω resistor R 2 , which is selectively placed in series with the output circuit by selecting the appropriate position of a single pole, single throw switch SW 2 . Although Applicant has found that 22 Ω is an appropriate value for the resistor R 2 , it is noted that the value is selected empirically in order to obtain the user desired tactile feel for the “low” output selection. Additionally, those of ordinary skill in the art will recognize that the resistor R 2  may be replaced with a potentiometer, thereby providing a fully adjustable output power level. 
   Although the driver circuit  43  has been described as being integral with the signal source  41 , it should be appreciated that the present invention contemplates that any necessary driver circuit  43  may be provided as part of the tactile transducer  23 . In this manner, the signal source  41  may be utilized with virtually any type of tactile transducer  23 , the driver circuit  43  being adapted to provide all necessary electrical compatibility between the chosen tactile transducer  23  and the signal source  41 . In such an implementation, the driver circuit  43  should be provided with an input jack J 1  for receiving signals from the signal generator  42 . 
   In any case, as previously discussed, the tactile metronome  20  of the present invention is preferably adapted to impart to a musician  48  tactile stimulations indicative of tempo and measure timing, as shown in  FIG. 9 , as well as of tempo, measure timing and complex rhythmic patterns, as shown in  FIG. 10 . In particular, the preferred embodiment of the present invention contemplates imparting tempo information by the timing of the beginning of signal outputs from the signal generator  42 . In order to differentiate downbeats, indicative of measure timing, the signal generator  42  is adapted under the control of the controller  47  to produce a signal output of longer duration than those indicative of divisional beats, the former of which will be noticeably perceived by the musician  48  as being of much greater intensity than the latter, especially when imparted through the foregoing described vibrating transducer  24 . As shown in  FIG. 9 , the controller  47  is programmed to implement these aspects of the present invention by simply effecting at a set tempo a repeating pattern of output pulses from the signal generator  42  representing the downbeats and divisional beats. 
   As shown in  FIG. 10 , however, the tactile metronome  20  of the present invention is also preferably adapted to impart to a musician  48  tactile stimulations indicative of not only tempo and measure timing, but also complex rhythmic patterns. In this case, the controller  47  is preferably programmed to “follow” the score of a user chosen musical selection. In the alternative, however, the controller  47  may be pre-programmed with a plurality of rhythmic patterns, which may be simply selected through user input to the controller  47 . As will be appreciated by those of ordinary skill in the art, the latter will have great utility in mastering basic rhythms. In any case, the preferred embodiment of the present invention contemplates that an appropriate programming interface be provided to allow the user to input to the controller  47  any desired rhythmic pattern or, for that matter, an entire musical score. As shown in  FIG. 10 , the controller  47  controls the signal generator  42  to produce output pulses only when the score calls for a note to be performed, giving greater duration, or intensity, to those pulses corresponding to downbeats. 
   While the foregoing description is exemplary of the preferred embodiment of the present invention, those of ordinary skill in the relevant arts will recognize the many variations, alterations, modifications, substitutions and the like as are readily possible, especially in light of this description, the accompanying drawings and claims drawn thereto. In any case, because the scope of the present invention is much broader than any particular embodiment, the foregoing detailed description should not be construed as a limitation of the scope of the present invention, which is limited only by the claims appended hereto.