JP6398192B2 - Electronic stringed instruments and programs - Google Patents

Description

  The present invention relates to a string position detection device, an electronic string instrument, and a string position detection method.

  Conventionally, as an electronic stringed instrument such as an electronic guitar, a so-called pitch extraction type that extracts a string vibration period (pitch) from string vibration generated when a string is picked and determines a pitch of a sound to be generated based on the pitch. Electronic stringed instruments are known (for example, see Patent Document 1).

  In addition, there is known an electronic stringed instrument in which a contact switch is provided at each fret of a guitar and a pitch of a sound to be generated and a performance method are determined according to an on / off state of the switch (see, for example, Patent Document 2).

JP-A-5-232950 Japanese Patent No. 3716499

  However, in the so-called pitch extraction type electronic stringed musical instrument as described in Patent Document 1, the pitch is extracted by analyzing the string vibration generated when the string is played. There is a problem in that a delay time occurs. Particularly in the case of a bass with a long period, it takes time to extract the pitch, and thus there is a problem that the delay in sound generation becomes long.

  In addition, in an electronic stringed instrument having a switch on each fret as described in Patent Document 2, the delay time of pronunciation is shorter than that of a pitch extraction type electronic stringed instrument, but the conventional acoustic guitar and electric guitar, There is a problem that it lacks operability and realism.

  The present invention has been made in view of such circumstances, and while maintaining the appearance, operability, and realism of a conventional guitar in the same manner as in the past, it is possible to produce a precise sound by suppressing a delay in pronunciation. An object of the present invention is to provide a string position detection device, an electronic stringed instrument, and a string position detection method that can be performed.

In order to achieve the above object, an electronic stringed musical instrument according to one aspect of the present invention is provided.
A first detector having a plurality of detectors arranged in a direction different from the direction in which the strings stretched on the fingerboard surface are arranged and arranged at a first inclination angle that is not parallel to the fingerboard surface. A sensor,
A second sensor having a plurality of detectors arranged in a direction different from the string extending direction and arranged in a second inclination angle different from the first inclination angle with respect to the fingerboard surface; ,
Based on the detection state of the string by the plurality of detection units arranged in the first sensor and the second sensor, the coordinate position of the string with a predetermined position as a reference, and with respect to the finger plate surface Calculating means for calculating a coordinate position including a coordinate component in a first direction different from the parallel direction and a coordinate component in a second direction different from the first direction ;
Is provided.

  According to the present invention, the string position detecting device, electronic device capable of producing accurate sound by suppressing the delay of sound generation while maintaining the appearance, operability, and real feeling of the conventional guitar in the same manner as in the past. A stringed instrument and a string position detection method can be provided.

It is a top view which shows the external appearance of the electronic stringed musical instrument 1 which concerns on one Embodiment of this invention. 3 is an enlarged perspective view of a neck 20. FIG. 2A and 2B are diagrams illustrating an arrangement state of a sensor control board 51, a first sensor board 42, and a second sensor board 43 arranged in the neck 20, wherein FIG. 5A is a perspective view, and FIG. It is sectional drawing of the part by which the board | substrate 42 is arrange | positioned, (c) is sectional drawing of the part by which the 2nd sensor board | substrate 43 is arrange | positioned. It is a figure which shows the 1st sensor board | substrate 42 and 1st image sensor 45A, and the 2nd sensor board | substrate 43 and the 2nd image sensor 45B, Comprising: (a) is a top view, (b) is a side view. It is a figure which shows the sensor control board 51, the light source 52, and the connector 53, Comprising: (a) is a top view, (b) is the sectional view on the AA line of (a). It is a block diagram which shows the structure of the periphery of the electronic part 13 of the electronic stringed instrument 1 which concerns on one Embodiment of this invention. It is a whole block diagram explaining the calculation method of the absolute position of the string. It is a figure explaining the calculation method of the absolute position of the string 22, Comprising: It is a figure explaining the method of calculating the coordinate determined from the mechanism of the neck 20. FIG. It is a figure explaining the calculation method of the absolute position of the string 22, Comprising: It is a figure explaining the calculation method of the coordinate of the string. It is a figure explaining the calculation method of the relative position of the string.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Outline of electronic stringed instrument 1]
First, with reference to FIG. 1, the outline | summary of the electronic stringed instrument 1 provided with the string position detection apparatus as one Embodiment of this invention is demonstrated.

  FIG. 1 is a plan view showing an appearance of an electronic stringed instrument 1 according to an embodiment of the present invention. As shown in FIG. 1, the electronic stringed musical instrument 1 is configured as an electronic guitar, and includes a main body 10, a neck 20, and a head 30.

  The head 30 includes a bobbin 31 around which one end of a steel string 22 is wound. A plurality of frets 23 are provided on the fingerboard surface 21 of the neck 20. A plurality (one or more) of strings 22 are stretched on the fingerboard surface 21. In the present embodiment, six strings 22 and 22 frets 23 are provided. Each of the six strings 22 is associated with a string number. The thinnest string 22 is the string number “1”, and the string number increases in the order of increasing the thickness of the string 22. Each of the 22 frets 23 is associated with a fret number. The fret 23 closest to the head 30 has the fret number “1”, and the fret number of the arranged fret 23 increases as the distance from the head 30 side increases.

  The main body 10 includes a bridge 16 to which the other end of the string 22 is attached, a pickup 11 that detects vibration of the string 22, a tremolo arm 17 for adding a tremolo effect to the sound to be emitted, and an inside of the main body 10. A built-in electronic unit 13, a cable 14 for connecting each string 22 and the electronic unit 13, and a display unit 15 for displaying the type of tone and the like are provided.

[Internal configuration of neck 20]
Next, the internal configuration of the neck 20 will be described.
FIG. 2 is an enlarged perspective view of the neck 20. 3A and 3B are diagrams showing the arrangement of the sensor control board 51, the first sensor board 42, and the second sensor board 43 arranged inside the neck 20, wherein FIG. 3A is a perspective view, and FIG. Is a cross-sectional view of a portion where the first sensor substrate 42 is disposed, and (c) is a cross-sectional view of a portion where the second sensor substrate 43 is disposed. 4A and 4B are diagrams showing the first sensor board 42 and the first image sensor 45A, and the second sensor board 43 and the second image sensor 45B, where FIG. 4A is a plan view and FIG. 4B is a side view. FIG. 5A and 5B are diagrams showing the sensor control board 51, the light source 52, and the connector 53, where FIG. 5A is a plan view, and FIG. 5B is a cross-sectional view taken along line AA in FIG.

  As shown in FIG. 1, the neck 20 is formed so as to extend from the main body 10 of the electronic stringed instrument 1 in a predetermined direction. As shown in FIGS. 1 to 3, the neck 20 includes a case portion 24 that extends in the longitudinal direction and a fingerboard surface 21 that extends in the longitudinal direction.

  Inside the neck 20, a sensor control board 51, a first sensor board 42, and a second sensor board 43 are arranged. Details of the sensor control board 51, the first sensor board 42, and the second sensor board 43 will be described later.

  As shown in FIGS. 2 and 3, in the cross section of the case portion 24 in the width direction (direction perpendicular to the longitudinal direction of the case portion 24), the back side of the case portion 24 is formed in an arc shape, and the front side of the case portion 24 is It is formed to be recessed inward. A groove-like arrangement portion 25 where the sensor control board 51 is arranged, a first inclined arrangement portion 26 where the first sensor board 42 is arranged, and a second sensor board 43 are arranged at the bottom inside the case portion 24. The second inclined arrangement portion 27 is formed. The case portion 24 is formed of, for example, a wood carving that carved the inner surface of a semi-cylindrical wood or a resin material.

  As shown in FIGS. 2 and 3, the groove-shaped arrangement portion 25 is formed in a planar shape that is recessed from the front side of the case portion 24 at the center in the width direction (direction orthogonal to the longitudinal direction) inside the case portion 24. The The groove-shaped arrangement portion 25 extends in a groove shape over the entire longitudinal direction of the case portion 24.

  The first inclined arrangement portion 26 and the second inclined arrangement portion 27 are formed side by side in the longitudinal direction of the case portion 24 inside the case portion 24. The first inclined arrangement portion 26 and the second inclined arrangement portion 27 are formed between the adjacent frets 23 as a set of the first inclined arrangement portion 26 and the second inclined arrangement portion 27. The first inclined arrangement portion 26 and the second inclined arrangement portion 27 are formed such that a plurality of sets are arranged in the longitudinal direction of the case portion 24 and the first inclined arrangement portion 26 and the second inclined arrangement portion 27 are alternately arranged. ing.

  As shown in FIG. 3, the first inclined arrangement portion 26 is closer to the finger plate surface 21 than the groove-shaped arrangement portion 25 in the direction in which the string 22 is pressed (the thickness direction of the finger plate surface 21 and the depth direction of the neck 20). In addition, the first upper inclined surface 26 a and the first lower inclined surface 26 b that are separated in the width direction of the case portion 24 across the groove-shaped arrangement portion 25 are configured. The first upper inclined surface 26a and the first lower inclined surface 26b are formed on the same plane, and the first sensor substrate 42 is disposed on the first upper inclined surface 26a and the first lower inclined surface 26b. The The first upper inclined surface 26 a and the first lower inclined surface 26 b are arranged to be inclined by a predetermined angle θ with respect to the finger plate surface 21. In the present embodiment, for example, the first upper inclined surface 26a and the first lower inclined surface 26b in the first inclined arrangement portion 26 are cross-sectional in the width direction (direction perpendicular to the longitudinal direction) of the neck 20 as shown in FIG. As shown in (b), the angle θ is inclined with respect to the finger plate surface 21 so as to approach the finger plate surface 21 from the one end 20 a side in the width direction of the neck 20 toward the other end 20 b side.

  The second inclined arrangement portion 27 is arranged adjacent to the first inclined arrangement portion 26 in the longitudinal direction of the case portion 24. The second inclined arrangement portion 27 is located closer to the finger plate surface 21 than the groove arrangement portion 25 in the direction in which the string 22 is pressed (the thickness direction of the finger plate surface 21 and the depth direction of the neck 20). The second upper inclined surface 27a and the second lower inclined surface 27b are spaced apart in the width direction of the case portion 24. The second upper inclined surface 27a and the second lower inclined surface 27b are formed on the same plane, and the second sensor substrate 43 is disposed on the second upper inclined surface 27a and the second lower inclined surface 27b. The

  The second upper inclined surface 26a and the second lower inclined surface 27b are not parallel to the first upper inclined surface 26a and the first lower inclined surface 26b in the first inclined arrangement portion 26, respectively. In addition, the first inclined surface 26b is inclined at a predetermined angle α and the finger plate surface 21 is inclined at an angle θ. In the present embodiment, for example, the second upper inclined surface 27a and the second lower inclined surface 27b in the second inclined arrangement portion 27 are cross-sectional in the width direction (direction perpendicular to the longitudinal direction) of the neck 20 as shown in FIG. As shown in (c), the angle θ is inclined with respect to the finger plate surface 21 so as to approach the finger plate surface 21 from the other end 20b side in the width direction of the neck 20 toward the one end 20a side.

  The fingerboard surface 21 is formed in a plate shape and extends in the longitudinal direction of the neck 20. The fingerboard surface 21 is disposed on the front side of the neck 20. The fingerboard surface 21 has a neck 20 so as to close a recessed portion of the case portion 24 in a state where the sensor control board 51, the first sensor board 42, and the second sensor board 43 are arranged inside the case portion 24. It is arranged on the front side. At least a part of the fingerboard surface 21 is formed of a transparent material that transmits light so that the first image sensor 45 </ b> A and the second image sensor 45 </ b> B can recognize images of the plurality of strings 22. Note that light may be transmitted by forming a transmission window on the fingerboard surface 21. Further, using a material having a property of transmitting light only from one side, such as a so-called magic mirror, the first image sensor 45A and the second image sensor 45B can recognize the images of the plurality of strings 22 and perform the player. May hide its internal structure.

  As shown in FIG. 3B, the first sensor substrate 42 is arranged in the first inclined arrangement portion 26 inside the neck 20. As shown in FIG. 4, a first image sensor 45 </ b> A having a pixel portion and a connector 48 are mounted on the first sensor substrate 42. The first sensor substrate 42 is fixed to the case portion 24 of the neck 20 by a screw member 49.

A plurality of first image sensors 45A are provided, and each first image sensor 45A is provided corresponding to each of the plurality of frets 23.
The first image sensor 45 </ b> A is mounted on the surface side of the first sensor substrate 42, and has a first detection surface 46 </ b> A formed in a planar shape parallel to the mounting surface of the first sensor substrate 42. The first detection surface 46A is disposed to face each of the plurality of strings 22 (see FIG. 7). The first image sensor 45A detects the position of each of the plurality of strings 22 on the first detection surface 46A. The first image sensor 45A is configured to be able to recognize each of the plurality of strings 22 as an image, and includes an image sensor that detects the position of each of the plurality of strings 22 by the first detection surface 46A by image recognition.

  By arranging the first sensor substrate 42 on the first inclined arrangement portion 26, the first detection surface 46 </ b> A of the first image sensor 45 </ b> A has the one end 20 a side in the width direction of the neck 20 downward with respect to the fingerboard surface 21. In such a state that it is inclined at an angle θ, it is arranged to face the string 22 (see FIG. 3B). The connector 48 is mounted on the back surface side of the first sensor board 42 and connected to a connector 53 (described later) mounted on the sensor control board 51 via a connector cable 58 (see FIG. 3B).

  As shown in FIG. 3C, the second sensor substrate 43 is arranged on the second inclined arrangement portion 27 inside the neck 20. As shown in FIG. 4, the second sensor substrate 43 is mounted with a second image sensor 45B having a pixel portion and a connector 48, as with the first sensor substrate. The second sensor substrate 43 is fixed to the case portion 24 of the neck 20 by a screw member 49.

A plurality of second image sensors 45B are provided, and each second image sensor 45B is provided corresponding to each of the plurality of frets 23.
The second image sensor 45 </ b> B is mounted on the surface side of the second sensor substrate 43 and has a second detection surface 46 </ b> B formed in a planar shape parallel to the mounting surface of the second sensor substrate 43. The second detection surface 46B faces each of the plurality of strings 22 and is arranged at an angle that is not parallel to the first detection surface 46A (see FIG. 7). The second image sensor 45B detects the position of each of the plurality of strings 22 on the second detection surface 46B. The second image sensor 45B is configured to be able to recognize each of the plurality of strings 22 as an image, and includes an image sensor that detects the position of each of the plurality of strings 22 by the second detection surface 46B by image recognition.

  Since the second sensor substrate 43 is arranged on the second inclined arrangement portion 27, the second detection surface 46B of the second image sensor 45B is the first detection of the first image sensor 45A mounted on the first sensor substrate 42. The first detection surface 46A is arranged so as to be inclined at a predetermined angle α so as not to be parallel to the surface 46A (see FIGS. 3A and 7). The second detection surface 46B is disposed to face the string 22 with the angle θ inclined so that the other end 20b side in the width direction of the neck 20 is downward with respect to the fingerboard surface 21 (FIG. 3B). )reference). The connector 48 is mounted on the back side of the second sensor substrate 43 and is connected to the connector 53 mounted on the sensor control substrate 51 via the connector cable 58.

  The image sensors 45A and 45B mounted on the first sensor substrate 42 and the second sensor substrate 43 are configured by elements such as a CCD (Charge Coupled Devices) and a CMOS (Complementary Metal Oxide Semiconductor) that convert an optical image into an image signal. The

  On the upper surfaces of the detection surfaces 46A and 46B of the image sensors 45A and 45B on the first sensor substrate 42 and the second sensor substrate 43, an optical lens 47 is disposed as shown in FIG. As shown in FIG. 3B, the optical lens 47 is disposed closer to the plurality of strings 22 than the first image sensor 45A and the second image sensor 45B, and the field of view of the first image sensor 45A and the second image sensor 45B. Provided to enlarge.

  As shown in FIGS. 2 and 3, the sensor control board 51 is arranged in the groove-like arrangement portion 25 of the case portion 24 inside the neck 20. The sensor control board 51 is formed so as to extend in the longitudinal direction of the neck 20. On the surface side of the sensor control board 51, as shown in FIG. 5, a light source 52 as a light emitting means and a connector 53 are mounted. The sensor control board 51 is fixed to the case portion 24 of the neck 20 by a screw member 54.

  As shown in FIG. 5, the light sources 52 are formed so as to extend in the width direction (direction orthogonal to the longitudinal direction) of the sensor control board 51, and a plurality of light sources 52 are arranged at a predetermined distance in the longitudinal direction of the sensor control board 51. The The light source 52 irradiates each of the plurality of strings 22 with light so that the first image sensor 45 </ b> A and the second image sensor 45 </ b> B can recognize images of the plurality of strings 22. The light emitted from the light source 52 is applied to the plurality of strings 22 through a portion of the fingerboard surface 21 made of a transmissive material or a transmission window.

  The connectors 53 are arranged side by side in the longitudinal direction of the sensor control board 51 alternately on one side and the other side in the width direction of the sensor control board 51. The connector 53 is connected to a connector 48 mounted on the first sensor board 42 and the second sensor board 43 via a connector cable 58 (see FIGS. 3B and 3C).

[Configuration around the electronic unit 13]
Next, a configuration around the electronic unit 13 will be described with reference to FIG. FIG. 6 is a block diagram showing a configuration around the electronic unit 13 of the electronic stringed instrument 1 according to the embodiment of the present invention.

As illustrated in FIG. 6, the electronic unit 13 includes a control unit 61, a sound source unit 62, and a storage unit 64.
The control unit 61 controls the operation of each unit in the electronic stringed instrument 1. The control unit 61 executes various processes according to a program recorded in the internal ROM or a program loaded from the storage unit 64.

  As shown in FIG. 6, the control unit 61 is electrically connected to the pickup 11, the image sensors 45 </ b> A and 45 </ b> B, the display unit 15, and the sound source unit 62.

  The sound source unit 62 generates waveform data of a musical tone whose sound is instructed by, for example, MIDI (Musical Instrument Digital Interface) data, and outputs an audio signal obtained by D / A conversion of the waveform data to the acoustic device 63.

  The control unit 61 calculates coordinates that are positions of the plurality of strings 22 on the fingerboard surface 21 based on the positions of the plurality of strings 22 detected by the first image sensor 45A and the second image sensor 45B. It also functions as a calculation means. Based on the positions of the plurality of strings 22 detected by the first image sensor 45A and the second image sensor 45B, the controller 61 parallels the fingerboard surface 21 with respect to each of the plurality of strings 22 (the direction in which the strings 22 are arranged). The coordinates in the width direction of the neck 20) and the coordinates in the direction perpendicular to the fingerboard surface 21 (the direction in which the string 22 is pressed, the depth direction of the neck 20) are calculated.

The control unit 61 also functions as a string-pressing position detection unit that detects a string-pressing position on the fingerboard surface 21 based on the calculated change in position of each of the plurality of strings 22.
The control unit 61 also functions as a sound generation instruction means for instructing the connected sound source unit 62 to generate a musical sound based on the detected string pressing position.

  The controller 61 calculates the absolute position of each of the plurality of strings 22 with respect to the fingerboard surface 21. Further, the control unit 61 calculates a relative position where each of the plurality of strings 22 has changed from a predetermined reference position.

Specifically, the control unit 61 calculates the absolute position of the string 22 or the relative position of the string 22 as follows.
First, a method for calculating the absolute position of the string 22 will be described with reference to FIGS. The absolute position of the string 22 is calculated in consideration of parameters determined from the mechanism of the neck 20.
FIG. 7 is an overall configuration diagram illustrating a method for calculating the absolute position of the string 22. FIG. 8 is a diagram for explaining a method for calculating the absolute position of the string 22, and is a diagram for explaining a method for calculating coordinates determined by the mechanism of the neck 20. FIG. 9 is a diagram illustrating a method for calculating the absolute position of the string 22 and a diagram illustrating a method for calculating the coordinates of the string 22.

7 to 9, the coordinate system sets a horizontal coordinate that is parallel to the fingerboard surface 21 (the direction in which the strings 22 are arranged, the width direction of the surface of the fingerboard surface 21) as the horizontal coordinate x, and the right side. Was set as positive and the left side was set as negative. Also, as the vertical coordinate z, the vertical coordinate that is perpendicular to the fingerboard surface 21 (the direction in which the chord 22 is pressed, the thickness direction of the fingerboard surface 21, the depth direction of the neck) is set, with the upper side being positive and the lower side being Was set to minus.
The horizontal coordinate x corresponds to the coordinate in the width direction (the direction in which the plurality of strings 22 are arranged) on the surface of the fingerboard surface 21. The vertical coordinate z corresponds to the coordinate in the direction in which the string 22 is pressed (the thickness direction of the fingerboard surface 21 and the depth direction of the neck 20).

The meaning of each variable shown in FIGS. 7 to 10 is as follows.
Pi (xi, zi): x coordinate of the string 22 of the string number “i”, z coordinates x _A , x _B : position P _{A of the} string 22 observed by the image sensors 45A, 45B (px _A , pz _A ) , P _B (px _B , pz _B ): If x _A , x _B are known, coordinates L, z _L determined from the mechanism of the neck 20: horizontal distance from the origin O to one end of the image sensors 45A, 45B, and depth (Depth)
θ: Inclination angle of image sensors 45A and 45B

  As shown in FIG. 7, when the string 22 is not pressed, the i-th string 22 from the left is located at the coordinate Pi (xi, zi). The first detection surface 46A of the first image sensor 45A mounted on the first sensor substrate 42 is disposed to face the i-th string 22 from the left, and is angled from the horizontal direction so that the positive side of the x coordinate is downward. It is arranged with an inclination of θ. The second detection surface 46B of the second image sensor 45B mounted on the second sensor substrate 44 is disposed to face the i-th string 22 from the left, and is angled from the horizontal direction so that the minus side of the x coordinate is downward. It is arranged with an inclination of θ. 46A of 1st detection surfaces and 46B of 2nd detection surfaces are arrange | positioned with the angle (alpha) so that it may not become parallel.

As shown in FIG. 8, the first image sensor 45A and the second image sensor 45B observe the position of the i-th string 22 from the left. The first image sensor 45A, the first detection surface 46A and the coordinates _{P A} at the intersection of the perpendicular line beat from the i-th chord 22 from the left to the first detection surface 46A of the first image sensor 45A of the first image sensor 45A Observe (px _A , pz _A ). The second image sensor 45B has the coordinates P _B of the intersection of the second detection surface 46B of the second image sensor 45B and the perpendicular line extending from the i-th string 22 from the left to the second detection surface 46B of the second image sensor 45B. Observe (px _B , pz _B ).

Then, coordinates from P _A, the upper side of the end portion X _A and the upper side of the end portion X _B and coordinates an intersection point between perpendicular line beat to the connected line the H of the second image sensor 45B of the first image sensor 45A _A. From the coordinate P _B, and coordinates H _B of intersection between the upper end X _A and the upper end portion X _B and the perpendicular to beat to the connected line of the second image sensor 45B of the first image sensor 45A .
Thereby, the coordinate P _A (px _A , pz _A ) and the coordinate P _B (px _B , pz _B ) can be expressed using the coordinate H _A or the coordinate H _B as follows.

As shown in FIG. 8, the x coordinate (px _A ) of the coordinate P _A is a coordinate obtained by moving + X _{A HA} (+ x _A cos θ) from −L on the x coordinate, as shown in the following equation (i): expressed.
px _A = −L + x _A cos θ (i)
Further, z coordinates of _{P A} (pz _A) from -z _L on the _{z-coordinate, -H A P A (-x A} sinθ) is moved coordinates is expressed by the following equation (ii) The
pz _A = −z _L −x _A sin θ (ii)

In addition, the x coordinate (px _B ) of the coordinate P _B is a coordinate obtained by moving −X _B H _B (−x _B cos θ) from + L on the x coordinate, and is represented by the following equation (iii).
px _B = L−x _B cos θ (iii)
Further, z coordinates of _{P B} (pz _B) from -z _L on the _{z-coordinate, -H B P B (-x B} sinθ) is moved coordinates is expressed by the following equation (iv) The
pz _B = −z _L −x _B sin θ (iv)

Next, as shown in FIG. 9, the distance from the chord 22 to the coordinate P _A is d _A and the distance from the chord 22 to the coordinate P _B is d _B. Also, let V _A be the intersection of a perpendicular line extending from the coordinate P _A to the line extending from the coordinate Pi in parallel with the z-axis. Further, the intersection point of the perpendicular line extending from the coordinate P _B to the line extending from the coordinate Pi in parallel to the z-axis is defined as V _B.

As shown in FIG. 9, the x coordinate (xi) of the coordinate Pi is a coordinate obtained by moving + P _A V _A from px _A on the x coordinate, while −P _B V from px _B on the x coordinate. It is also the coordinate which moved _B , and is represented by the following formula (1).
xi = px _A + P _A V _A = px _B −P _B V _B (1)

Further, as shown in FIG. 9, the z coordinate (zi) of the coordinate Pi is a coordinate obtained by moving + PiV _A from pz _A on the x coordinate, and on the other hand, it is moved + PiV _B from pz _B on the x coordinate. It is also a coordinate and is expressed by the following formula (2).
zi = pz _A + PiV _A = pz _B + PiV _B (2)

Further, in FIG. 9, the following equations (3) to (6) are established.
P _A V _A = d _A sin θ (3)
P _B V _B = d _B sin θ (4)
PiV _A = d _A cos θ (5)
PiV _B = d _B cos θ (6)

Here, when the expressions (3) to (6) are substituted into the expressions (1) and (2), the following expressions (7) and (8) are obtained.

When Expression (7) and Expression (8) are solved for d _A and d _B , the following Expression (9) and Expression (10) are obtained.

Substituting Equations (9) and (10) into Equations (7) and (8) yields the following Equations (11) and (12).

Then, the equation (11) and (12) by substituting the formula (i) ~ expression including L and _{z L} determined by the mechanism of the neck 20 (vi), determined by the mechanism of the neck 20 L and _{z L} The absolute position of the string 22 can be calculated in consideration of these parameters.
As described above, the control unit 61 can calculate the absolute position of the string 22 with respect to the fingerboard surface 21.

  Note that the calculation method of the absolute position of the string 22 in the present embodiment is a calculation method when the optical lens 47 is not provided. In the present embodiment, the optical lens 47 can be disposed on the detection surfaces 46A and 46B of the image sensors 45A and 45B. Therefore, when such an optical lens 47 is arranged, it is necessary to correct the detection position variation caused by the provision of the optical lens 47 from the coordinates obtained from the above formula.

Next, a method for calculating the relative position of the string 22 by the control unit 61 will be described with reference to FIG. FIG. 10 is a diagram for explaining a method for calculating the relative position of the string 22.
The coordinate system is the same as when the absolute position of the string 22 is calculated.

Although calculation in the middle of the calculation method of the coordinates of the position of the string 22 in the control unit 61 is omitted, the following equations (20) and (21) are obtained from the diagram shown in FIG.

The equation (20) and (21) is not to be dependent on L and _{z L} determined by the mechanism of the neck 20 expression. Thereby, the change amounts Δzi and Δxi from the reference position Pi can be calculated. Therefore, since the amount of Δzi can be calculated, it can be determined whether or not the string 22 is pressed. Since the amount of Δxi can be calculated, it can be determined whether or not the chord 22 is choked.

In this way, in the method of calculating the relative position of the string 22, the control unit 61 calculates the variation from the reference position Pi of the string 22, thereby depending on L and z _L determined from the mechanism of the neck 20. Instead, the relative position of the string 22 from the reference position of the string 22 can be detected. Thereby, the detection of the position of the string 22 is not easily affected by the manufacturing variation of the neck 20, and the detection accuracy of the position of the string 22 can be improved.

[Sounding operation of electronic stringed instrument 1]
Next, the sounding operation of the electronic stringed instrument 1 will be described.
First, the performer presses the string 22. Thereby, the first image sensor 45A and the second image sensor 45B detect the position of the string 22. Then, the control unit 61 calculates the coordinates of the position of the string 22 based on the position of the string 22 detected by the first image sensor 45A and the second image sensor 45B. Here, the control unit 61 may detect the absolute position of the string 22 or may detect the relative position of the string 22.

Thereby, the control unit 61 performs the player when the movement of the string 22 in the depth direction (thickness direction of the fingerboard surface 21) exceeds the predetermined threshold, based on the calculated coordinates of the string 22, for example. It is possible to detect which fret 23 is pressed between.
Further, when choking, which is one of the guitar playing methods, the string 22 changes in the x direction. Therefore, based on the calculated coordinates of the strings 22, the control unit 61 performs choking, for example, when there is a movement in a direction in which a plurality of strings 22 exceeding a predetermined threshold is aligned (the width direction of the fingerboard surface 21). Can be detected.

  As described above, it is possible to calculate the position of each string 22 for each fret 23. Thereby, for example, the z-coordinate of a certain string 22 is pressed in a minus direction by a predetermined value or more from the reference position (the difference between the z-coordinate of each string 22 and the z-coordinate of each string 22 is a predetermined value or less). In this case, the fret 23 in which each string 22 is pressed can be extracted by determining that the string 22 is pressed in the fret 23.

  Then, at the stage where all the pressed frets 23 of each string 22 are determined, for example, among the frets 23 determined to be pressed for each string 22, the guitar bridge 16 side (the side closest to the main body) ) Is determined as a position where the string 22 is pressed (pressed position), and when the string 22 is plucked, sound generation based on the pressed position can be performed.

  By doing so, it is possible to generate a correct sound as soon as the performer plucks while maintaining the same appearance and operability as those of a conventional acoustic guitar or electric guitar.

  Further, when movement of a certain string 22 in the width direction (x direction) is detected, a conventional acoustic guitar or electric guitar is changed by changing the pitch of the sound generated according to the movement amount. As with, it is possible to produce a sound with a choking effect.

  As described above, when the player presses the string, the pitch (string vibration period) can be determined from the pressed position. Therefore, the pitch (string vibration period) can be determined before the performer plucks the string. Thus, when the pickup 11 detects that the performer has plucked, the sound source unit 62 is operated on the basis of the pitch (string vibration period) information already determined from the pressed position to generate a correct pitch. Data can be transmitted to the audio device 63. Therefore, the repulsion has become a problem in the case of a so-called pitch extraction type electronic stringed instrument that extracts the string vibration period (pitch) from the string vibration generated when the string is picked and detects the pressed position with respect to the fret from the pitch. Without causing a delay from the string to the determination of the pitch, it is possible to immediately control the sound generation with the correct pitch after being plucked. In particular, it is possible to suppress a delay in pronunciation for a bass having a long cycle.

Heretofore, the configuration and operation of the electronic stringed instrument 1 of the present embodiment have been described.
In this embodiment, it has the 1st detection surface 46A arrange | positioned facing the some string 22 stretched on the fingerboard surface 21, and each position of the some string 22 in the said 1st detection surface 46A. A first image sensor 45A for detecting the second detection surface 46B, and a second detection surface 46B disposed at an angle that faces the plurality of strings 22 and is not parallel to the first detection surface 46A. A second image sensor 45B that detects the position of each of the one or more strings 22 on the fingerboard surface 21 based on the positions of the plurality of strings 22 detected by the first image sensor 45A and the second image sensor 45B. And a controller 61 for calculating the position of each of the plurality of strings 22 in FIG.

  Therefore, when the player presses the string, the pitch (string vibration period) can be determined from the pressed position. Therefore, the pitch (string vibration period) can be determined before the performer plucks the string. Thus, when the pickup 11 detects that the performer has plucked, the sound source unit 62 is operated based on the pitch (string vibration period) information already determined from the pressed position, and the sound generation data is transmitted to the acoustic device. 63 can be transmitted. Therefore, it is possible to suppress the delay in sound generation, and it is possible to generate sound with the correct pitch immediately after plucking. Therefore, while maintaining the conventional guitar appearance, operability, and realism in the same manner as in the past, it is possible to produce a sound with an accurate sound by suppressing a delay in sound generation.

  Further, in the present embodiment, the control unit 61 determines the fingerboard surface 21 of each of the plurality of strings 22 based on the position of each of the plurality of strings 22 detected by the first image sensor 45A and the second image sensor 45B. Calculate parallel and vertical positions. Therefore, by calculating the coordinates of the string 22, it is possible to detect the movement of the string 22 in the direction parallel to the fingerboard surface 21 and the movement of the string 22 in the direction perpendicular to the fingerboard surface 21.

  In the present embodiment, the first image sensor 45A and the second image sensor 45B are configured to recognize each of the plurality of strings 22 as an image, and at least a part of the fingerboard surface 21 is formed of a transmissive material. Alternatively, a transmission window is formed on the fingerboard surface 21. Therefore, the first image sensor 45 </ b> A and the second image sensor 45 </ b> B can be arranged on the opposite side of the fingerboard surface 21 from the string 22. Thereby, a space for providing the first image sensor 45 </ b> A and the second image sensor 45 </ b> B can be secured on the back side of the fingerboard surface 21. Thereby, for example, the first image sensor 45A and the second image sensor 45B can be arranged at positions that do not impair the appearance of the stringed instrument such as the inside of the case body arranged on the back side of the fingerboard surface 21.

  In the present embodiment, the first image sensor 45A and the second image sensor 45B further include a light source 52 that irradiates each of the plurality of strings 22, and the light emitted from the light source 52 is a fingerboard surface. The plurality of strings 22 are irradiated through a portion formed of a transmissive material 21 or a transmissive window. Therefore, by irradiating the string 22 with the light source 52, the first image sensor 45A and the second image sensor 45B can improve the recognition accuracy of the images of the plurality of strings 22.

  In the present embodiment, the optical lens 47 for enlarging the field of view of the first image sensor 45A and the second image sensor 45B can be disposed on the plurality of strings 22 side. Therefore, even if the field of view of the light receiving portions of the first image sensor 45A and the second image sensor 45B is narrow, the field of view can be enlarged by the optical lens 47, and the position of the string 22 can be detected by image recognition.

  In the present embodiment, the control unit 61 calculates the absolute position of each of the plurality of strings 22 with respect to the fingerboard surface 21. Therefore, by calculating the absolute position of the string 22, it is possible to detect movement of the string 22 in the pressing direction and movement in the direction in which the strings 22 are arranged.

In the present embodiment, the control unit 61 calculates a relative position where each of the plurality of strings 22 has changed from a predetermined reference position. Therefore, by calculating the relative position of the strings 22, it is possible to detect movement of the strings 22 in the pressing direction and movement in the direction in which the strings 22 are arranged. Further, the relative position of the string 22 from the initial position of the string 22 can be detected without depending on L and z _L determined by the mechanism of the neck 20. Thereby, the detection of the position of the string 22 is not easily affected by the manufacturing variation of the neck 20, and the detection accuracy of the position of the string 22 can be improved.

  As mentioned above, although embodiment of this invention was described, embodiment is only an illustration and does not limit the technical scope of this invention. The present invention can take other various embodiments, and various modifications such as omission and replacement can be made without departing from the gist of the present invention. These embodiments and modifications thereof are included in the scope and gist of the invention described in this specification and the like, and are included in the invention described in the claims and the equivalents thereof.

  In the above-described embodiment, the electronic guitar has been described as an example of the electronic stringed instrument to which the present invention is applied. Can also be configured.

  In the above-described embodiment, the first detection surface 46 </ b> A of the first image sensor 45 </ b> A is disposed at an angle θ with respect to the horizontal direction so that the positive side of the x coordinate is downward with respect to the fingerboard surface 21. . The second detection surface 46B of the second image sensor 45B is disposed at an angle θ with respect to the horizontal direction so that the minus side of the x coordinate is downward with respect to the fingerboard surface 21. However, the angle at which the first detection surface 46A of the first image sensor 45A and the second detection surface 46B of the second image sensor 45B are arranged is not limited to this. For example, one of the first detection surface 46A of the first image sensor 45A and the second detection surface 46B of the second image sensor 45B is arranged in parallel in the horizontal direction (fingerboard surface 21), and the other is You may arrange | position so that it may incline from a horizontal direction (finger board surface 21). In the above-described embodiment, the angle at which the first detection surface 46A of the first image sensor 45A and the second detection surface 46B of the second image sensor 45B are disposed is the same angle θ, but is not limited thereto. The angles may be different from each other.

  In the above-described embodiment, the optical lens 47 is disposed on the upper surfaces of the detection surfaces 46A and 46B of the image sensors 45A and 45B on the first sensor substrate 42 and the second sensor substrate 43, but the present invention is not limited to this. If the detection surfaces 46A and 46B of the image sensors 45A and 45B are large enough to recognize a plurality of string images, the optical lens need not be provided.

The invention described in the scope of claims at the beginning of the filing of the present application will be appended.
[Appendix 1]
A first sensor having a first detection surface disposed opposite to the one or more strings stretched on the fingerboard surface, and detecting a position of each of the one or more strings on the first detection surface;
A second detection surface disposed opposite to the one or more strings and at an angle not parallel to the first detection surface, wherein the positions of the one or more strings on the second detection surface are detected; A second sensor that,
Calculating means for calculating the positions of the one or more strings on the fingerboard surface based on the positions of the one or more strings detected by the first sensor and the second sensor;
A string position detection device comprising:
[Appendix 2]
The calculating means determines positions of the one or more strings in a direction parallel to and perpendicular to the fingerboard surface based on the positions of the one or more strings detected by the first sensor and the second sensor. The string position detection apparatus according to claim 1 to calculate.
[Appendix 3]
A plurality of the first sensor and the second sensor are provided, and a plurality of frets are provided on the fingerboard surface, and each of the first sensor and the second sensor corresponds to each of the plurality of frets. The string position detection apparatus according to claim 1, wherein the string position detection apparatus is provided.
[Appendix 4]
And further comprising light emitting means for irradiating each of the one or more strings.
The first sensor and the second sensor are configured to recognize each of the one or more strings as an image, and at least a part of the fingerboard surface is formed of a transmissive material, or on the fingerboard surface. A transmissive window is formed,
The light emitted from the light emitting means is applied to the one or more strings through a portion formed of a transmissive material on the fingerboard surface or the transmission window. The string position detection device according to claim 1.
[Appendix 5]
5. The string position detection device according to claim 1, wherein an optical lens for enlarging a field of view of the first sensor and the second sensor is disposed on the one or more string sides. 6.
[Appendix 6]
The string position detection device according to any one of claims 1 to 5,
A string-pressing position detecting means for detecting a string-pressing position on the fingerboard surface based on the calculated change in the position of each of the one or more strings;
A sound generation instruction means for instructing a connected sound source to generate a musical sound based on the pressed position detected by the pressed position detection means;
Electronic stringed instrument with
[Appendix 7]
A first sensor having a first detection surface disposed opposite to the one or more strings stretched on the fingerboard surface, and detecting a position of each of the one or more strings on the first detection surface; A second detection surface disposed opposite to the one or more strings and at an angle not parallel to the first detection surface, wherein the positions of the one or more strings on the second detection surface are detected; A string position detecting method used for a string position detecting device having a second sensor, wherein the string position detecting device includes:
A string position detection method for calculating a position of each of the one or more strings on the fingerboard surface based on a position of each of the one or more strings detected by the first sensor and the second sensor.

  DESCRIPTION OF SYMBOLS 1 ... Electronic string instrument, 20 ... Neck, 21 ... Finger board surface, 22 ... String, 23 ... Fret, 45A ... 1st image sensor, 45B ... 2nd image sensor , 46A ... first detection surface, 46B ... second detection surface, 47 ... optical lens, 61 ... control unit, 62 ... light source.

Claims (10)

A first detector having a plurality of detectors arranged in a direction different from the direction in which the strings stretched on the fingerboard surface are arranged and arranged at a first inclination angle that is not parallel to the fingerboard surface. A sensor,
A second sensor having a plurality of detectors arranged in a direction different from the string extending direction and arranged in a second inclination angle different from the first inclination angle with respect to the fingerboard surface; ,
Based on the detection state of the string by the plurality of detection units arranged in the first sensor and the second sensor, the coordinate position of the string with a predetermined position as a reference, and with respect to the finger plate surface Calculating means for calculating a coordinate position including a coordinate component in a first direction different from the parallel direction and a coordinate component in a second direction different from the first direction ;
A string position detection device comprising: The string position detection apparatus according to claim 1, wherein the calculation unit calculates the coordinate position based on a detection state of the string by the plurality of detection units and the first inclination angle. The first sensor and the second sensor are arranged to face a plurality of strings stretched on the fingerboard surface,
The calculation unit calculates the coordinate position for each of the plurality of strings on the fingerboard surface based on detection states of the plurality of strings by the plurality of detection units. 2. The string position detection device according to 2. Said calculation means, said first direction is a direction perpendicular to the finger plate surface, the second direction is one of the claims 1-3, characterized in that a direction parallel to the fingerboard surface chord position detection apparatus according to an item or. A plurality of the first sensors and the second sensors are provided, and a plurality of frets are provided on the fingerboard surface, and each of the first sensors and the second sensors is provided corresponding to each of the plurality of frets. The string position detection device according to claim 4 , wherein The string position detection device according to claim 1, wherein the first sensor and the second sensor are sensors that detect light. A light emitting means for irradiating the string with light;
The first sensor and the second sensor are configured to recognize the string as an image, and at least a part of the fingerboard surface is formed of a transmissive material, or a transmission window is formed on the fingerboard surface. And
The string position detection apparatus according to claim 6 , wherein the light emitted from the light emitting unit is applied to the string through a portion formed of a transmissive material on the finger plate surface or the transmission window. The string position detection device according to any one of claims 1 to 7 , further comprising an optical lens arranged on the one or more string sides for enlarging the field of view of the first sensor and the second sensor. A string position detection device according to any one of claims 1 to 8 ,
A string-pressing position detecting means for detecting a string-pressing position on the fingerboard surface based on the calculated change in the position of the string;
A sound generation instruction means for instructing a connected sound source to generate a musical sound based on the pressed position detected by the pressed position detection means;
Electronic stringed instrument with A string position detection method used in a string position detection device that detects a string position using a sensor,
A first detector having a plurality of detectors arranged in a direction different from the direction in which the strings stretched on the fingerboard surface are arranged and arranged at a first inclination angle that is not parallel to the fingerboard surface. A sensor and a plurality of detectors arranged in a direction different from the string extending direction and arranged in a second inclination angle different from the first inclination angle with respect to the fingerboard surface. Identifying the detection state of the strings by the plurality of detection units arranged in two sensors ,
The coordinate position of the string based on a predetermined position based on the state of detection of the string by the plurality of detection units specified, and in a first direction different from a direction parallel to the fingerboard surface And calculating a coordinate position including a coordinate component in a second direction different from the first direction .

Images